WASTE COOKING OIL TO BIODIESEL FUEL

WASTE COOKING OIL TO BIODIESEL FUEL Ahmad J Al-Kofahi, 2017 American University of Beirut (AUB) Green Technologies, Energy 1 TABLE OF CONTENT 1 BIODIESEL BASICS ........................................................................................................................ 6 1.1 What is biodiesel ............................................................................................................................. 6 1.2 Why biodiesel ................................................................................................................................. 6 1.3 History of biodiesel ......................................................................................................................... 6 1.4 Review of biodiesel feedstock ......................................................................................................... 6 1.5 Fuel properties ................................................................................................................................ 6 1.6 The advantages of using vegetable oils as source of fuels ............................................................... 7 1.7 Characteristics of oils or fats affecting their suitability for use as biodiesel ..................................... 8 1.8 Vegetable oils as starting material for biodiesel fuels ...................................................................... 9 1.9 Biodiesel conversion process .......................................................................................................... 9 1.9.1 2 Transesterification of Vegetable Oil ....................................................................................... 9 BIODIESEL FROM WASTE VEGITABLE OIL ......................................................................... 11 2.1 What is waste vegetable oil ........................................................................................................... 11 2.2 Types of collected waste oils......................................................................................................... 11 2.3 12 2.4 Domestic waste oil treatment ........................................................................................................ 12 2.5 Oil collection considerations ......................................................................................................... 12 2.6 Properties of biodiesel from waste cooking oil............................................................................... 13 2.6.1 ...................................................................................................................................................... 13 2.7 Storage of biodiesel and some challenges ..................................................................................... 14 2.8 Overview of Biodiesel Production Using Waste Oil, Pros and Cons ............................................. 14 2.8.1 2.9 3 Some disadvantages for using biodiesel fuel ................................................................................. 15 BIODIESEL AS AN ENGINE FUEL ............................................................................................. 15 3.1 Technical characteristics of biodiesel as a transportation fuel ....................................................... 15 3.2 Engine emissions from biodiesel ................................................................................................... 16 3.2.1 Using B100 ........................................................................................................................... 16 3.2.2 Case of Blend ....................................................................................................................... 18 3.2.3 Injection Characteristics and Reducing NOx ......................................................................... 19 3.2.4 Reduction in Carbon Dioxide Emissions when Using Biodiesel ........................................... 20 3.2.5 Biodegradability of Biofuels (Another Advantage) ............................................................... 20 3.2.6 Emissions & Greenhouse Gas Reduction Emissions: ............................................................ 21 4 5 Environmental benefits (biodiesel vs. petroleum) ................................................................. 14 ENVIRONMENTAL IMPACTS .................................................................................................... 22 4.1 Waste vegetable oils ..................................................................................................................... 22 4.2 Emissions ...................................................................................................................................... 22 4.3 Life Cycle Reduction of CO2: ....................................................................................................... 23 4.4 A Safe and Stable Fuel: ................................................................................................................. 23 4.5 Recycling: ..................................................................................................................................... 23 4.6 Waste Disposal and Byproducts .................................................................................................... 23 BIODIESEL ECONOMY FROM WASTE OIL ........................................................................... 24 2 5.1 Economic Impacts of Biodiesel ..................................................................................................... 24 5.2 The Glycerin By-Product: ............................................................................................................. 25 5.3 Program Cost Estimates ................................................................................................................ 25 6 CASE STUDIES .............................................................................................................................. 26 6.1 Case study: Daphne Utilities, Alabama ......................................................................................... 26 6.2 Case study: Biodiesel Lebanon ..................................................................................................... 27 7 8 CONCLUSION AND RECOMMENDATIONS ............................................................................ 28 7.1 Conclusions .................................................................................................................................. 28 7.2 Recommendations: ........................................................................................................................ 28 REFERENCES: ............................................................................................................................... 29 3 List of tables Table 1: Technical properties of biodiesel 7 Table 2: Comparison of properties of: waste cooking oil, biodiesel from waste cooking oil, and commercial diesel fuel. 13 Table 3: The effect of ester content on degradation rates of mineral diesel. 21 Table 4: Fuel consumption using biodiesel Error! Bookmark not defined. 4 List of figures Figure 1: The transesterification process of converting vegetable oils to biodiesel 10 Figure 2: Simplified flow diagram of base-catalyzed biodiesel processing 10 Figure 5: Sample of waste cooking oil 11 Figure 6: Types of collected oils 12 Figure 7: collection of waste oils 13 Figure 28: Outdoor, above ground storage tanks 14 Figure 10: Mean values for the effects of rapeseed biodiesel on the emissions from a number of engines. 17 With sunflower biodiesel, the reduction in HC was the same as rapeseed biodiesel, and CO and PM were further reduced, but NOx emissions increased. (Figure 11) 17 Figure 12: Mean values of the effects of sunflower biodiesel on the emissions from a number of engines. 17 Figure 13: The effect of waste olive oil biodiesel (100%) on the percentage of changes in emissions from a diesel engine compared with diesel at various loads 18 Figure 14: The percentage of change in emissions when 50% sunflower biodiesel blend is used in a marine diesel engine at various loads (kW) compared with diesel. 18 Figure 15: The effect of various concentrations of commercial biodiesel added to diesel in a four-stroke direct injection single cylinder diesel outboard engine. 19 Figure 16: Percentage of change in steady state emissions from a soy biodiesel fuelled Navistar HEUI diesel engine. 19 Figure 17: Effect of injection advance on emissions, the normal setting for diesel is 23°. 20 Figure 18: Biodegradation of various bio diesel preparations over 21 days 20 Figure 19: Average emission impacts of biodiesel for heavy-duty highway engines 21 Figure 20: B100 emissions compared to petroleum diesel emissions by percentage 22 Figure 22: Payback period reduction through higher biodiesel production volumes 25 Figure 23: Fuel economy measured as brake-specific fuel consumption (BSFC) using soybean oil biodiesel in a four-stroke DDC series 60 diesel engine. Error! Bookmark not defined. Figure 24 : The effect of the oil used to produce biodiesel on the brake-specific fuel consumption (BSFC). The biodiesel was mixed at 20% and used in a single cylinder, four-stroke direct injection diesel engine. Error! Bookmark not defined. Figure 25: Fuel consumption (g/h) for marine diesel and a blend (50%) with sunflower biodiesel at various loads in a single cylinder diesel engine. Error! Bookmark not defined. Figure 26 summarizes the different sources used in biodiesel production. 25 Figure 27: The routes to the production of alternative biodiesel diesels capable of replace petro -diesel 26 5 1 BIODIESEL BASICS 1.1 What is biodiesel Biodiesel is a combustible fuel that is biodegradable and made from vegetable oil or animal fat. It is desirable as an alternative to petroleum fuel because it uses renewable resources that are less damaging to the environment to produce and emit less harmful greenhouse gasses when burned as fuel. Biodiesel fuel can be used in any vehicle with a compression ignition engine (CIE) that can take regular diesel fuel. With the proper equipment and safety procedures, used cooking oil can be prepared from kitchens or restaurants to simply make biodiesel fuel. 1.2 Why biodiesel The bad impacts of fossil fuel on the environment and climate change have been increased in the recent years. Its primary advantages deal with Biodiesel being one of the most renewable fuels currently available and it is also non-toxic and biodegradable. It can also be used directly in most diesel engines without requiring extensive engine modifications. However, the cost of biodiesel is the major obstacle to its commercialization in comparison to petroleum-based diesel fuel. The high cost is primarily due to the raw material, mostly neat vegetable oil. Since biofuels can help reduce the dependency on foreign oil and help provide a way where supply can meet the demand, more research studies need to be carried out in order to improve the energy ratios. In conclusion, biodiesel produced from waste vegetable/animals oil and fats can compete with the prices of petroleum diesel without national subsidies 1.3 History of biodiesel In 1900, Dr. Rudolf Diesel, a scientist who patented the first diesel engine, demonstrated a working diesel engine using peanut oil as a fuel. Diesel believed that the use of a biomass fuel was the real future of his engine. At first, Diesel was interested in running his engine either on coal or vegetable based fuels. Prior to his mysterious death in 1913, Rudolph Diesel stated that “the use of vegetable oils as engine fuels may seem insignificant today but such oils may become, in the course of time, as important as petroleum and the coal tar products of the present time.” Thus, earlier, petroleum-based fuels were used mostly due to the higher cost and the weight problem associated with diesel. However, recent attempts to reduce greenhouse gas emissions associated with burning fuel, encouraged further research for vegetable-based fuels as substitutes. Using vegetablebased fuels, the carbon dioxide in the atmosphere is changed to carbon-based compounds by plants in a process called photosynthesis. The carbon is then biologically converted to high -energy starches, celluloses, proteins, and oils. 1.4 Review of biodiesel feedstock Biodiesel feedstock can be categorized into three groups: vegetable oils (edible or non-edible oils), animal fats and used waste cooking oil including triglycerides. But also a variety of oils can be used to produce biodiesel, algae, which can be grown using waste materials such as sewage and without displacing land currently used for food production and oil from halophytes such as salicornia bigelovii, which can be grown using saltwater in coastal areas where conventional crops cannot be grown, with yields equal to the yields of soybeans and other oilseeds grown using freshwater irrigation. Many advocates suggest that waste vegetable oil is the best source of oil to produce biodiesel, but since the available supply is drastically less than the amount of petroleum- based fuel that is burned for transportation and home heating in the world; this local solution does not scale well. 1.5 Fuel properties Raw vegetable oil cannot meet biodiesel fuel specifications because it is not registered, It is not a legal motor fuel, and it is high viscosity so burns poorly (poor atomization and varnish formation). However, it is important that the fuel produced meets the biodiesel ASTM standards, otherwise there could be engine damage. The high viscosity vegetable oil must be chemically converted to operate properly in a diesel engine; Biodiesel conversion process does this. The reaction between the fat or oil and the alcohol is a 6 reversible reaction, so the alcohol must be added in excess to drive the reaction towards the right and ensure complete conversion. Biodiesel is found as a clear yellow liquid whose viscosity is very similar to petroleum diesel. Unlike petro-diesel, it is nonflammable, non-explosive, nontoxic and biodegradable. The Flash Point (FP) is defined as the flash point temperature of a fuel which is the minimum temperature at which the fuel will ignite (flash) on application of an ignition source. Flash point varies inversely with the fuel’s volatility. Minimum flash point temperatures are required for proper safety and handling of diesel fuel. The flash point of some biodiesels is 150oC compared to 64 oC for petrodiesel which makes Biodiesel-fueled vehicles much safer in accidents than those powered by diesel or gasoline. Chemically, biodiesel consists of long chain alkyl esters (especially ethyl esters) of long -chain fatty acids derived from natural lipids via the trans-esterification process. The ester behaves as the backbone of the biodiesel’s chemical formula. It is an organic compound in which a hydrogen atom from the carboxyl group of the fatty acid is replaced with an alkyl group. Technically, pure biodiesel is known as B100 (100%) or neat biodiesel. Normally B100 is not used in vehicle engines due to engine warranty concerns. However, operation with biodiesel blends may result in very slightly lower mpg due to lower energy content. Table 1 shows some technical properties of B100. Commercial biodiesel is sold as a “blend” with regular ultra-low sulfur diesel (ULSD), example is B10 (10% biodiesel and 90% petroleum diesel). Currently, most vehicles are warranted up to B20 (20 biodiesel). Chemical name Chemical formula range Kinematic viscosity range Density range Boiling point range FP range Vapor pressure Solubility in water Physical appearance Odor Biodegradability Reactivity Fatty acid (m)ethyl ester C14-C24 methyl esters or C15-25 H28-48O2 3.3-5.2 mm2/s, at 40oC 860-894 kg/m3, at 15oC 200oC 155-180oC Less than 5 mm Hg at 22 oC Insoluble in water; however, biodiesel can absorb up to 1500 ppm water Light to dark yellow, clear liquid Light musty/soapy odor More biodegradable than petrodiesel Stable, but reacts with strong oxidizers Table 1: Technical properties of biodiesel (B100) 1.6 The advantages of using vegetable oils as source of fuels Vegetable oils are liquid fuels from renewable sources; they do not over-burden the environment with emissions. Vegetable oils have potential for making marginal and productive by their property of nitrogen fixation in the soil. Their production requires slighter energy input in production. Vegetable oil combustion has cleaner emission spectra and simpler processing technology. But these are not economically feasible yet and need further R&D work for development of on farm processing technology. Due to the rapid decline in crude oil reserves, the use of vegetable oils as diesel fuels is again promoted in many countries. Depending up on climate and soil conditions, different nations are looking into different vegetable oils for diesel fuels. An acceptable alternative fuel for engine has to fulfill the environmental and energy security needs without sacrificing operating performance. Vegetable oils can be successfully used in CI engine 7 through engine modifications and fuel modifications because vegetable oil in its raw form cannot be used in engines. It has to be converted to a more engine-friendly fuel called biodiesel. Biodiesel has comparable energy density, cetane number, heat of vaporization, and stoichiometric air/fuel ratio with mineral diesel. The large molecular size of the component triglycerides result in the oil having higher viscosity compared with that of mineral diesel. Viscosity affects the handling of t he fuels by pump and injector system, and the shape of fuel spray. Biodiesel is biodegradable, non-toxic and essentially free from sulfur; it is renewable and can be produced from agriculture and plant resources. Biodiesel is an alternative fu el, which has a correlation with sustainable development, energy conservation, management, efficiency and environmental preservation. 1.7 Characteristics of oils or fats affecting their suitability for use as biodiesel Calorific Value, Heat of Combustion – The calorific value of biodiesel is about 37.27 MJ/kg. This is 9% lower than regular Number 2 petrodiesel. Variations in biodiesel energy density are more dependent on the feedstock used than the production process. Still, these variations are less than fo r petrodiesel. Pour Point or Melt Point - Melt or pour point refers to the temperature at which the oil in solid form starts to melt or pour. In cases where the temperatures fall below the melt point, the entire fuel system including all fuel lines and fuel tank will need to be heated Cloud Point - The temperature at which oil starts to solidify is known as the cloud point. While operating an engine at temperatures below oil’s cloud point, heating will be necessary in order to avoid waxing of the fuel. Flash Point - The flash point temperature of a fuel is the minimum temperature at which the fuel will ignite (flash) on application of an ignition source. Flash point varies inversely with the fuel’s volatility. Minimum flash point temperatures are required for proper safety and handling of diesel fuel. Iodine Value - Iodine Value (IV) is a value of the amount of iodine, measured in grams, absorbed by 100 grams of given oil. Iodine value (or Iodine number) is commonly used as a measure of the chemical stability properties of different biodiesel fuels against such oxidation as described above. The Iodine value is determined by measuring the number of double bonds in the mixture of fatty acid chains in the fuel by introducing iodine into 100 grams of the sample under test and measuring how many grams of that iodine are absorbed. Iodine absorption occurs at double bond positions - thus a higher IV number indicates a higher quantity of double bonds in the sample, greater potential to polymerize and hence lesser stability. Viscosity – Viscosity refers to the thickness of the oil, and is determined by measuring the amount of time taken for a given measure of oil to pass through an orifice of a specified size. Viscosity affects injector lubrication and fuel atomization. Fuels with low viscosity may not provide sufficient lubrication for the precision fit of fuel injection pumps, resulting in leakage or increased wear. Fuel atomization is also affected by fuel viscosity. Diesel fuels with high viscosity tend t o form larger droplets on injection which can cause poor combustion, increased exhaust smoke and emissions. Cetane Number - Is a relative measure of the interval between the beginning of injection and auto ignition of the fuel. The higher the cetane number, the shorter the delay interval and the greater its combustibility. Fuels with low Cetane Numbers will result in difficult starting, noise and exhaust smoke. In general, diesel engines will operate better on fuels with Cetane Numbers above 50. Cetane tests provide information on the ignition quality of a diesel fuel. Research using cetane tests will provide information on potential tailoring of vegetable oil-derived compounds and additives to enhance their fuel properties. Density – Is the weight per unit volume. Oils that are denser contain more energy. For example, petrol and diesel fuels give comparable energy by weight, but diesel is denser and hence gives more energy per liter. The aspects listed above are the key aspects that determine the efficiency of a fuel for diesel engines. There are other aspects/characteristics which do not have a direct bearing on the performance, but are important for reasons such as environmental impact etc. These are: 8 Ash Percentage - Ash is a measure of the amount of metals contained in the fuel. High concentrations of these materials can cause injector tip plugging, combustion deposits and injection system wear. The ash content is important for the heating value, as heating value decreases with increasing as h content. Ash content for bio-fuels is typically lower than for most coals, and sulphur content is much lower than for many fossil fuels. Unlike coal ash, which may contain toxic metals and other trace contaminants, biomass ash may be used as a soil amendment to help replenish nutrients removed by harvest. Sulfur Percentage - The percentage by weight, of sulfur in the fuel Sulfur content is limited by law to very small percentages for diesel fuel used in on-road applications. 1.8 Vegetable oils as starting material for biodiesel fuels Vegetable oils have become more attractive recently because of its environmental benefits and the fact that it is made from renewable resources. Vegetable oils have the potential to substitute a fraction of petroleum distillates and petroleum-based petro chemicals in the near future. The fundamental of vegetable oils is triglyceride. Vegetable oils comprise 90% to 98% triglycerides and small amounts of mono- and diglycerides. These usually contain free fatty acids (FFAs), water, sterols, phospholipids, odorants and other impurities. Different types of vegetable oils have different types of fatty acids. The advantages of vegetable oils as diesel fuel are their portability, ready availability, renewability, higher heat content (about 88% of D2 fuel), lower sulfur content, lower aromatic content, and biodegradability. The main disadvantages of vegetable oils as diesel fuel are higher viscosity, lower volatility, and the reactivity of unsaturated hydrocarbon chains. The injection and atomization characteristics of the vegetable oils are significantly different than those of petroleum-derived diesel fuels, mainly as the result of their high viscosities. The vegetable oils, as alternative engine fuels, are all extremely viscous with visco sities ranging from 9 to 17 times greater than that of petroleum-derived diesel fuel. Modern diesel engines have fuel-injection system that is sensitive to viscosity change. One way to avoid these problems is to reduce fuel viscosity of vegetable oil in o rder to improve its performance. The vegetable oils may be blended to reduce the viscosity with diesel in presence of some additives to improve its properties. Heating and blending of vegetable oils may reduce the viscosity and improve volatility of vegetable oils but its molecular structure remains unchanged hence polyunsaturated character remains. Blending of vegetable oils with diesel, however, reduces the viscosity drastically and the fuel handling system of the engine can handle vegetable oil –diesel blends without any problems. The most common way of producing biodiesel is the transesterification of vegetable oils. The methyl ester produced by transesterification of vegetable oil has a high cetane number, low viscosity and improved heating value compared to those of pure vegetable oil which results in shorter ignition delay and longer combustion duration and hence low particulate emissions. Its use results in the minimization of carbon deposits on injector nozzles. 1.9 Biodiesel conversion process 1.9.1 Transesterification of Vegetable Oil Biodiesel production is the process of producing the biofuel, through the chemical reactions transesterification and esterification. This involves vegetable or animal fats and oils being reacted with short-chain alcohols (typically methanol or ethanol). It’s the process of separating the fatty acids from their glycerol backbone to form fatty acid esters (FAE) and free glycerol. The alcohols used should be of low molecular weight, ethanol being one of the most used for its low cost. However, greater conversions into biodiesel can be reached using methanol. The most common means of production is base-catalyzed transesterification. This path has lower reaction times and catalyst cost than those posed by acid catalysis. In this process, Fats/oils are reacted with alcohol (methanol), using a strong alkaline catalyst (sodium hydroxide NaOH or potassium hydroxide KOH). During the esterification process, the triglyceride is reacted with alcohol in the presence of a catalyst, usually a strong alkaline like sodium hydroxide. The alcohol reacts with the fatty acids to form the mono-alkyl ester, or biodiesel, and crude glycerol. As shown in Fig 1, the large vegetable oil molecule is reduced to about 1/3 its original size, lowering the viscosity making it similar to diesel fuel. The resulting fuel operates similar to diesel fuel in an engine. The reaction produces three molecules of an ester fuel from one molecule of vegetable oil. 9 Since the reaction is a reversible one, excess alcohol with adequate catalyst generally forces the reaction equilibrium toward the production of biodiesel esters and glycerol. Figure 1: The transesterification process of converting vegetable oils to biodiesel Biodiesel viscosity comes very close to that of mineral diesel hence no problems in the existing fuel handling system. Flash point of the biodiesel gets lowered after esterification and the cetane number gets improved. Even lower concentrations of biodiesel act as cetane number improver for biodiesel blend. Calorific value of biodiesel is also found to be very close to mineral diesel. Some typical observations from the engine tests suggested that the thermal efficiency of the engine generally improves; cooling losses and exhaust gas temperature increase, smoke opacity generally gets lower for biodiesel blends. Possible reason may be additional lubricity properties of the biodiesel; hence reduced frictional losses (FHP). The energy thus saved increases thermal efficiency, cooling lo sses and exhaust losses from the engine. The thermal efficiency starts reducing after a certain concentration of biodiesel. Flash point, density, pour point, cetane number, calorific value of biodiesel comes in very close range to that of mineral diesel. Currently, most of the biodiesel produced is Base-catalyzed trans-esterification (Figure 2). Figure 2: Simplified flow diagram of base-catalyzed biodiesel processing 10 2 2.1 BIODIESEL FROM WASTE VEGITABLE OIL What is waste vegetable oil Waste vegetable (cooking) oils (WVOs) act as the best source for biomass since they can be found in huge quantities anywhere in the world. WVOs defined as any refined vegetable oils obtained from restaurants, houses, food courts, snack bars, cafeterias, and lunch truck. Food production facilities may have waste oil in bulk storage. However, some municipalities have collection sites for residential cooking oils. The oil supplier(s) should be scheduled early and confirm their participation if using cafeteria or restaurant fryer oil. The higher the quality of the oil, the easier it is to produce high quality fuel. Used cooking oil is normally black, a strong odor and does not have large amount of solids because its collection is passed through a fine mesh. Figure 1, shows a sample of used oil from the hotel sector. Figure 3: Sample of waste cooking oil The waste cooking oil is generated from the fried food, which need large amounts of oil because it requires the full immersion of food at temperatures greater than 180 °C. Accordingly to the high temperatures are generated changes in its chemical and physical composition, as well as in its organoleptic properties which affect both the food and oil quality. Reuse of domestic oil has a high risk to the health of consumers as depending on the type of food subjected to frying, “this absorbs between 5% and 20% of the used oil, which can increase significantly the amount of hazardous compounds that provide degraded oil to food”. Waste cooking oil can often be obtained for free or already treated for a small price. One disadvantage of using waste oil is it must be treated to remove impurities like free fatty acids (FFA) before conversion to biodiesel is possible. 2.2 Types of collected waste oils Fresh oil is the best collected oil which doesn't include free fatty acids or water but it is cost is high. On the other side, restaurant fryer oil which is typically all one oil type, may contain water and food particles, animal fats, high free fatty acids, so its cost relatively is lower than the fresh oil. The third type is the residential cooking oil which is mixed oils, contains food particles, water, animal fats, low in free fatty acids, highly variable volume and quality, only cost is collecting it (Figure 4). 11 Residential Cooking Oil Commercial Used Fryer Oil Figure 4: Types of collected oils 2.3 Domestic waste oil treatment Wastes containing these types of oils are products of decomposition that impair the oil qual ity causing reduction in productivity in the transesterification reaction and may also generate undesirable by-products which hurt the final product. For these reasons, it is important to refine the waste domestic oil for the biodiesel production. "This type of refinement has a right effect on the yield of the reaction from 67% to 87% after bleaching”. For the treatment of adequacy of waste domestic oil, the operations that can be applied are filtration, de-acidification or neutralization and whitening. The processes of degumming and deodorization aren't needed because the oils have already been treated prior to use and although during degradation odors occur, the removal is not essential for the biodiesel production. Filtration is an operation used for removing solids, inorganic material, and other contaminants in the oil. It can be carried out at temperatures higher than 60 °C, where substances carbonaceous produced from burnt organic material, pieces of paper, waste food and other solids are remov ed or occur at low temperatures which depend on the physical condition of the oil. In addition, we can delete solid fats or products of low melting points from the frying process. The deacidification is the process by which free oils fatty acids are removed, and to do so, various methods may be used. The first method is the neutralization with alkaline solution where the acids are removed in the form of soaps. The second one is the esterification with glycerin which seeks to regenerate the triglyceride. The third method is the extraction by solvents where it is used ethanol in proportions 1.3 times the amount of oil. The forth method is the distillation of fatty acids; this method requires a high energy cost. The final method is the removal of fatty acids with ion-exchange which is a resin of strongly basic character for the removal of free fatty acids and the color of the oil is used. However, the method that provides greater account of productivity in the removal of free fatty acids is the neutralization by caustic soda, since it not only are obtained high relations, but also helps in the bleaching of the oil, because made soaps help dragging the color generators. 2.4 Oil collection considerations Some consideration should be taken while collecting the waste oil. Visually sort incoming oil is important measure, if the liquid is milky, its either high in water, animal fats, or both, this liquid is rejected. Then oil should be screened to remove large food particles that could plug pumps. Then settling tank is used to remove oil and oil‐water mixture and to allow oil and oil emulsion to settle out (~24 hours) for removal before going to the processing tank. Once the oil is in the processing tank, it is heated and stirred for at least 12 hours to drive off any remaining water. 12 Figure 5: collection of waste oils Some factors are affecting the biodiesel reaction such as waste oil type. Bacon grease and other solid greases are not acceptable for biodiesel production since they raise the cloud point and could cause cold weather problems. Second factor is the restaurant fryer oils which tend to be high in free fatty acids which results in lower yields of biodiesel due to soap production during the reaction. Third factor is the high water content in the oil which impedes the biodiesel reaction resulting in only partial conversion of the oil to biodiesel. 2.5 Properties of biodiesel from waste cooking oil Table 2 shows comparison of properties of waste cooking oil, biodiesel from waste cooking oil and commercial diesel fuel. The properties of biodiesel and diesel fuels, in general, show many similarities, and therefore, biodiesel is rated as a realistic fuel as an alternative to diesel. This is due to the fact that the conversion of waste cooking oil into methyl esters through the transesterification process approximately reduces the molecular weight to one third, reduces the viscosity by about oneseventh, reduces the flashpoint slightly and increases the volatility marginally, and reduces pour point considerably. 2.5.1 Fuel property Kinematic viscosity (mm2/s, at 313 K) Density (kg/L, at 288 K) Waste Biodiesel from waste vegetabl vegetable oil e oil 36.4 5.3 0.924 0.897 Flash point(K) Pour point (K) Cetane number Ash content (%) 485 284 49 0.006 469 262 54 0.004 Sulfur content (%) Carbon residue (%) Water content (%) Higher heating value (MJ/kg) 0.09 0.46 0.42 41.40 0.06 0.33 0.04 42.65 Free fatty acid (mg KOH/g oil) Iodine value 1.32 141.5 0.10 - Commercia l diesel fuel 1.9–4.1 0.075– 0.840 340–358 254–260 40–46 0.008– 0.010 0.35–0.55 0.35–0.40 0.02–0.05 45.62– 46.48 - Table 2: Comparison of properties of: waste cooking oil, biodiesel from waste cooking oil, and commercial diesel fuel. 13 Used cooking oil is one of the economical sources for biodiesel production. However, the products formed during frying, can affect the transesterification reaction and the biodiesel properties. The production of biodiesel from waste vegetable oil offers a triple-facet solution: economic, environmental and waste management. The new process technologies developed during the last years made it possible to produce biodiesel from recycled frying oils comparable in quality to that of virgin vegetable oil biodiesel with an added attractive advantage of being lower in price. Thus, biodiesel produced from recycled frying oils has the same possibilities to be utilized. This project is about the manufacturing of biodiesel from the used vegetable oil. It aims to define the requirements for biodiesel production by the trans-esterification process, testing its quality by determining some parameters such as density, kinematics viscosity, high heating value, cetane number, flash point, cloud point and pour point and comparing it to diesel fuel, listing the environmental and economic benefits and drawback. This analysis is useful either when starting a new business, or identifying new opportunities for an existing business. Therefore, it will be extremely helpful for taking rational decisions about the development of a biodiesel production plant. 2.6 Storage of biodiesel and some challenges Some concerns should be taken into consideration while storing of biodiesel such as: winter concerns (fuel gelling in storage tank), water concerns (fuel stability reduced by bacterial growth if water is present), above ground storage tanks which are potentially vulnerable to low temperature problems, and splash blending of biodiesel with petroleum diesel will not work well at temperatures below the biodiesel gel point (typically 16‐32° F), but this can be handled by blending in kerosene as done with ULSD. Figure 6: Outdoor, above ground storage tanks Monitored vehicle performance and emissions of a 3 year study, showed that an above ground tank (Figure 28) to fuel 2 study vehicles using B20 for all winter driving that there is no adverse effects were seen either in the vehicles or in the Storage tank from the low winter temperatures. However, biodiesel can be stored and handled exactly like regular diesel fuel. It has a higher flashpoint (minimum 130°C) and is therefore safer than petroleum diesel fuel (minimum 52°C). Moreover, it is biodegradable; aids in keeping the fuel system clean, as well as improving the engine lubricity. 2.7 Overview of Biodiesel Production Using Waste Oil, Pros and Cons 2.7.1 Environmental benefits (biodiesel vs. petroleum) The steadily rising price of petroleum products and the environmental impact of procuring, manufacturing, and using them create the need for alternate energy sources. Biod iesel, fuel that is chemically prepared from vegetable oil, provides an environmentally friendly substitute for diesel fuel. It is classified as a biofuel because it originates from a biological source. Its biological origin makes it biodegradable and nontoxic. Tests sponsored by the United States Department of Agriculture confirm biodiesel is less toxic than table salt and biodegrades as quickly as sugar. Other 14 advantages of biodiesel fuel over petroleum diesel are the increased oxygen content, no sulfur content, increased lubricity, and lower emissions of particulate matter upon combustion. Absence of sulfur content (major components of acid rain) is desirable because sulfur indirectly increases carbon monoxide emissions by coating the catalytic converter, reducing its efficiency in catalyzing complete combustion of the gasoline to carbon dioxide. The increased lubricity provided by biodiesel, even in blends as low as 3%, prolongs engine life, with less frequent need for engine part replacement. Particulate matter is carbon and soot, so lowering these emission levels leads to cleaner air also. Biodiesel provides a means of recycling carbon dioxide, so there is no net increase in global warming. As with any complete combustion, carbon dioxide and water are the end products, but these will be taken up by the plant to ultimately lead to production of new biodiesel. Fossil fuels, which took millions of years to form, are not replenishable in the near future, whereas biofuels can ideally be replenished in one growing season. Based on engine testing, using the most stringent emissions testing protocols required by EPA for certification of fuels or fuel additives in the US, the overall ozone forming potential of the spectated hydrocarbon emissions from biodiesel was nearly 50 percent less than that measured for diesel fuel. While carbon monoxide emissions are reduced around 50% and carbon dioxide by around 78% overall based on the fact that the carbon comes from carbon already present in the earth’s atmosphere, not from its crust, as in petrodiesel. Fewer aromatic hydrocarbons are present a 56% reduction in benzofluoranthene and 71% reduction in benzopyrenes. The test shows that particulate emissions are reduced by up to 65%, leading to reduced cancer risks of up to 94% according to tests sponsored by the Department of Energy. Moreover, its higher cetane rating than petrodiesel causes more rapid ignition when injected into the engine. It also has the highest energy content of any alternative fuel in its pure form (B100). Pure biodiesel (B100) can be used in any petroleum diesel engine, though it is more commonly used in lower concentrations. The recent mandates for ultra -low sulfur petrodiesel make it necessary to use additives to increase lubricity and flow properties, so biodiesel is an obvious choice. Even the 2% formulation (B2) is capable of restoring lubricity to the fuel. B5 is often used in snow removal equipment and other municipal systems. Biodiesel is less flammable than gasoline or petrodiesel. 2.8 Some disadvantages for using biodiesel fuel Biodiesel has higher nitrogen oxide NOx emissions than petrodiesel. The higher NOx emissions may be due to the higher cetane rating and oxygen content of the fuel, so that atmospheric nitrogen is oxidized more readily. Catalytic converters and properly tuned engines can reduce these emissions. The flash point of biodiesel is higher than that of gasoline or petrodiesel, its gel point of varies depending on the ester composition. Most biodiesel has a somewhat higher gel and cloud point than petrodiesel. This requires the heating of storage tanks, especially in cooler climates. Biodiesel is hydrophilic because of its oxygen content that permits hydrogen bonding of water molecules. Water that is not removed during processing or present from storage tank condensation causes problems because it reduces the heat of combustion of the fuel, leading to more smoke, harder starting, and less power leads to corrosion of vital fuel system components fuel pumps such as injector pumps, fuel lines, etc. Moreover, biodiesel freezes to form ice crystals near 0 °C, which are sites for gel formation of the fuel, decreasing its flow properties. 3 3.1 BIODIESEL AS AN ENGINE FUEL Technical characteristics of biodiesel as a transportation fuel Just like petroleum diesel fuel, biodiesel operates in the compression ignition (diesel) engines. The successful introduction and commercialization of biodiesel in many countries around the world has been accompanied by the development of standards to ensure high product quality and user confidence. The biodiesel is characterized by determining its physical and fuel properties including density, viscosity, iodine value, acid value, cloud point, pure point, gross heat of combustion and volatility. In general, biodiesel compares well to petroleum-based diesel. The advantages of biodiesel as diesel fuel are its portability, ready availability, renewability, higher combustion e fficiency, lower sulfur and aromatic content, higher cetane number and higher biodegradability. The main disadvantages of biodiesel as diesel fuel are its higher viscosity, lower energy content, higher cloud point and pour point, higher nitrogen oxide emission, lower engine speed and power, injector coking, engine compatibility, high price, and higher engine wear. 15 Biodiesel offers safety benefits over diesel fuel because it is much less combustible, with a flash point greater than 150⁰C compared to 77⁰C for petroleum-based diesel fuel. Biodiesel has a higher cetane number (around 50) than diesel fuel, no aromatics, no sulfur, and contains 10–11% oxygen by weight. The cetane number is a commonly used indicator for the determination of diesel fuel quality, especially the ignition quality. It measures the readiness of the fuel to auto-ignite when injected into the engine. Ignition quality is one of the properties of biodiesel that is determined by the structure of the fatty acid methyl ester (FAME) component. Viscosity is the most important property of biodiesel since it affects the operation of the fuel injection equipment, particularly at low temperatures when the increase in viscosity affects the fluidity of the fuel. Biodiesel has a viscosity close to that of diesel fuels. High viscosity leads to poorer atomization of the fuel spray and less accurate operation of the fuel injectors. Due to presence of electronegative element oxygen, biodiesel is slightly more polar than diesel fuel as a result viscosity of biodiesel is higher than diesel fuel. Presence of elemental oxygen lowers the heating value of biodiesel when compared the diesel fuel. The lower heating value (LHV) is the most common value used for engine applications. It is used as an indicator of the energy content of the fuel. Biodiesel generally has a LHV that is 12% less than diesel fuel on a weight basis (16,000 Btu/lb compared with18,300 Btu/lb). Since the biodiesel has a higher density, the LHV is only 8% less on a volume basis (118,170 Btu/gallon for biodiesel compared with 129,050 Btu/gallon diesel fuel). Biodiesel can be used as pure fuel or blended at any level with petroleum-based diesel for use by diesel engines. The most common biodiesel blends are B2 (2% biodiesel and 98% petroleum diesel), B5 (5% biodiesel and 95% petroleum diesel), and B20 (20% biodiesel and 80% petroleum diesel). The technical disadvantages of biodiesel/petroleum diesel blends include problems with fuel freezing in cold weather, reduced energy density, and degradation of fuel under storage for prolonged periods. Biodiesel blends up to B20 can be used in nearly all diesel equipment and are compatible with most storage and distribution equipment. These low level blends generally do not require any engine modifications. Higher blends and B100 (pure biodiesel) may be used in some engines with little or no modification, although the transportation and storage of B100 requires special management. The characteristics of biodiesel are close to mineral diesel, and, therefore, biodiesel becomes a strong candidate to replace the mineral diesel if the need arises. The conversion of triglycerides into methyl or ethyl esters through the transesterification process reduces the molecular weight to one thirds that of the triglycerides, the viscosity by a factor of about eight and increases the volatility marginally. Biodiesel has viscosity close to mineral diesel. This vegetable oil esters contain10–11% oxygen by weight, which may encourage combustion than hydrocarbon-based diesel in an engine. The cetane number of biodiesel is around 50. Biodiesel has lower volumetric heating values (about 10%) than mineral diesel but has a high cetane number and flash point. The esters have cloud point and pour points that are 15–25 1C higher than those of mineral diesel. Biodiesel has low heating value, (8% lower than diesel) on weight basis because of presence of substantial amount of oxygen in the fuel but at the same time biodiesel has a higher specific gravity (0.88) as compared to mineral diesel (0.85) so overall impact is approximately 5% lower energy content per unit volume. Thermal efficiency of an engine operating on biodiesel is generally better than that operating on diesel. 3.2 Engine emissions from biodiesel 3.2.1 Using B100 One of the advantages of biofuels is the possible reduction in engine emissions which contribute to global warming and atmospheric pollution. Most of the studies have been carried out with the first generation biofuels, ethanol and biodiesel. Figure 7 shows the mean of a number of studies on the effect of using 100% rapeseed biodiesel on the important engine emissions: hydrocarbons (HC), CO, nitrous oxides (NOx), and PM. Rapeseed biodiesel is the main biodiesel produced in the EU and the consensus shows a considerable reduction in the emission of HC and PM and a small increase in NOx. The increase in NOx was probably due to an increase in combustion temperature. 16 Figure 7: Mean values for the effects of rapeseed biodiesel on the emissions from a number of engines. With sunflower biodiesel, the reduction in HC was the same as rapeseed biodiesel, and CO and PM were further reduced, but NOx emissions increased as shown in figure 8. Figure 8: Mean values of the effects of sunflower biodiesel on the emissions from a number of engines. A different result was observed when a 50% sunflower biodiesel blend was used in a marine diesel engine figure 9. With 50% sunflower biodiesel, the emissions decrease as for waste olive oil biodiesel but do not reach zero at the highest load. The advantages of using biodiesel to reduce emissions may therefore be eliminated when the engine is used at high loads. However, the reduction in emissions may depend on the test engine used. The emissions from an engine fuelled with 100% waste olive oil biodiesel at different loads are shown in figure 10. As the load increases the reduction in CO, NOx and sulfur dioxide decreases to zero at the highest load. 17 Figure 9: The effect of waste olive oil biodiesel (100%) on the percentage of changes in emissions from a diesel engine compared with diesel at various loads Figure 10: The percentage of change in emissions when 50% sunflower biodiesel blend is used in a marine diesel engine at various loads (kW) compared with diesel. 3.2.2 Case of Blend As the concentration of commercial biodiesel in blends increased, the emission of CO was reduced and NOx increased (Fig. 11). 18 Figure 11: The effect of various concentrations of commercial biodiesel added to diesel in a four-stroke direct injection single cylinder diesel outboard engine. In general, emissions from diesel engines running on blends or 100% biodiesel showed a reduction in CO, HC and PM, but an increase in nitrous oxide (NOx) levels (Figure 12). The reason for this change in emissions is thought to be the higher oxygen content of biodiesel, which gives a more complete combustion of the fuel and this reduces CO, HC and PM. Figure 12: Percentage of change in steady state emissions from a soy biodiesel fuelled Navistar HEUI diesel engine. 3.2.3 Injection Characteristics and Reducing NOx The reasons for the increased NOx production when using biodiesel may be the higher combustion temperature and injection characteristics. Advanced injection is caused by the higher bulk modulus of compressibility of biodiesel which allows the pressure wave from the pump to the nozzle to sp eed up, therefore advancing the timing. In order to reduce the emission of NOx with biodiesel, the injection timing was altered and the optimum setting was found to be 19° compared with 23° for diesel. The effect of altering the injection timing on emissions of CO and NOx is shown in Fig. 13. The lowest NOx emission was obtained at 21°, but the lowest CO emission was at 24°. In all the studies on emissions, no evidence has been given that the engines were optimized for biodiesel, and therefore modifications such as altering the timing may reduce emissions of NOx. Another way of reducing NOx production is to use exhaust gas recycling (EGR). Diesel engines fueled with Jatropha 19 oil biodiesel produce more NOx than diesel. In this case exhaust gas recirculation was tested as a system to reduce NOx. Figure 13: Effect of injection advance on emissions, the normal setting for diesel is 23°. 3.2.4 Reduction in Carbon Dioxide Emissions when Using Biodiesel Diesel produces around 80 g CO2/MJ compared with 43.7 g CO2/MJ for rapeseed biodiesel which is a reduction of 45%. Both natural gas and coal FT diesel produce more carbon dioxide than diesel. The amount of carbon dioxide produced by DME is similar to petrol and LPG. 3.2.5 Biodegradability of Biofuels (Another Advantage) They are non-toxic and degrade more rapidly than fossil fuels. This is an important feature in the case of accidents and spillages. Marine environments, freshwater, soil and various sediments ha ve been contaminated with oil components throughout the world as a result of accidents, leaks, spills and disposal. Oil components can cause considerable environmental disruption and the most spectacular are those accidents involving oil tankers. One definition of biodegradability is where a fuel is 90% or more degraded within 21 days under fixed conditions. Figure 14 shows the biodegradation of various bio diesel preparations over 21 days. Figure 14: Biodegradation of various bio diesel preparations over 21 days Mixing biodiesel with mineral diesel increases the rate of degradation of mineral diesel and as the concentration of biodiesel increases so does the rate of degradation (Table 3). The reason for the increase in degradation is not known but may be due either to the provision of a more accessible 20 substrate biodiesel or the solubilization of mineral diesel. Biodiesel has been shown to solubilize mineral diesel and has been used to remove crude oil from contaminated sand. Table 3: The effect of ester content on degradation rates of mineral diesel. 3.2.6 Emissions & Greenhouse Gas Reduction Emissions: Figure 15 shows the average emission impacts of biodiesel for heavy –duty highway engines: lower carbon monoxide (CO), lower particulate (PM), lower unburned hydrocarbons (HC), and increase or reduce NOx emissions depend on the engine design. Accordingly, using biodiesel helps in improving the environmental conditions. Figure 15: Average emission impacts of biodiesel for heavy-duty highway engines Biodiesel provides significantly reduced emissions of carbon monoxide, particulate matter, unburned hydrocarbons and sulfates compared to petroleum diesel fuel. Additionally, biodiesel re duces emissions of carcinogenic compounds by as much as 85% compared with petro diesel. When blended with petroleum diesel fuel, these emissions reductions are generally directly proportional to the amount of biodiesel in the blend. The reduced particulate and unburned hydrocarbons emissions that result when using biodiesel are a welcome relief in environments where workers and pedestrians are in close proximity to diesel engines, including public transport, mining, and construction. When high blends of biodiesel are used, the exhaust from diesel engines is often described as smelling like fried food, which aside from causing increased hunger in those nearby, is a welcome relief from the smell of diesel fuel exhaust. Diesel engines have long had a reputation of being “dirty” engines. However, with the advent of newer diesel engines equipped with exhaust gas recirculation (EGR), particulate filters, and catalytic converters, clean diesel technology provides incredible fuel efficiency with ultra-low emissions levels. When coupled with the use of biodiesel, both new and old diesel engines can significantly reduce emissions, including particulate matter (black smoke). 21 Figure 16: B100 emissions compared to petroleum diesel emissions by percentage 3 ENVIRONMENTAL IMPACTS 3.3 Waste vegetable oils Used cooking oil causes severe environmental problems, "a liter of oil poured into a water course can pollute up to 1000 tanks of 500 liters”. It’s feasible to demonstrate the contamination with the dumping of these oils to the main water sources. The oil which reaches the water sources increases its organic pollution load, to form layers on the water surface to prevent the oxygen exchange and alters the ecosystem. The dumping of the oil also causes problems in the pipes drain obstructing them and creating odors and increasing the cost of wastewater treatment. For this reason, has been necessary to create a way to recover this oil and reuse it. On the other hand, being derived from vegetable oils, biodiesel is naturally non-toxic. The acute oral LD50 (lethal dose) of biodiesel is more than 17.4 g/Kg. By comparison table salt (NaCl) has an LD50 of 3.0g/Kg. This means that table salt is almost 6 times more toxic than biodiesel. In an aquatic environment, biodiesel is 15 times less toxic to common species of fish than diesel fuel. In both soil and water, biodiesel degraded at a rate 4 times faster than regular diesel fuel, with nearly 80% of the carbon in the fuel being readily converted by soil and water born e organisms in as little as 28 day. 3.4 Emissions Emissions of particulate matter (Black Smoke) have been linked to respiratory diseases and are generally considered to be a human health hazard. Emissions of particulate matter are reduced with biodiesel by 47%. Carbon Monoxide is a poisonous gas and with biodiesel could be reduced by 48%. Total Unburned Hydrocarbons are compounds which contribute to localized formation of smog and by using biodiesel, they could be reduced by 67%. Nitrogen Oxides are compounds which contribute to localized formation of smog. The average effect of B20 on NOx is likely very close to zero. Sulfates are major contributors to acid rain. These emissions are practically eliminated when using biodiesel. Absence of sulfur content is desirable because sulfur indirectly increases carbon monoxide emissions by coating the catalytic converter, reducing its efficiency in catalyzing complete combustion of the gasoline to carbon dioxide. Polycyclic Aromatic Hydrocarbons or (PAH and nPAH have been identified as carcinogenic (cancer causing) compounds. Biodiesel reduces emissions of these compounds by up to 85% for PAH compounds and 90% for nPAH compounds. While Spectated Hydrocarbons are compounds contribute to the formation of localized smog and ozone. The potential for smog formation from spectated hydrocarbons is reduced by 50% when using biodiesel. Other advantages of biodiesel fuel over petroleum diesel are the increased oxygen content. The Clean Air Act of 1990 mandates oxygenated additives to be added to gasoline in cities with excessive levels of ozone and carbon monoxide pollution because they lead to a reduction in carbon monoxide emissions. Biodiesel contains about 11% oxygen by mass so no additional oxygenated additives are necessary. 22 3.5 Life Cycle Reduction of CO2: Biodiesel helps reduce the risk of global warming by reducing net carbon emissions to the atmosphere. When biodiesel is burned, it releases carbon dioxide to the atmosphere, but crops which are used to produce biodiesel take up carbon dioxide from the atmosphere in their growth cycle. A joint study conducted by the U.S. Department of Agriculture, and the U.S. Department of Energy determined that biodiesel reduces net carbon dioxide emissions to the atmosphere by 78.5% compared with petroleum diesel fuel. Though it is uncommon for the average person to come into direct contact with fuels, occasional spills do occur, and the impact of the fuel on plants and animals must be considered. Biodiesel has been proven to be much less toxic than diesel fuel, and is readily biodegradable. These attributes make it less likely to harm the environment if an accidental spill occurred, and far less costly to repair damage and clean up. 3.6 A Safe and Stable Fuel: Biodiesel is safer to handle than petroleum fuel because of its low volatility. Due to the high energy content of all liquid fuels, there is a danger of accidental ignition when the fuel is being stored, transported, or transferred. The possibility of having an accidental ignition is related i n part to the temperature at which the fuel will create enough vapors to ignite, known as the flash point temperature. The lower the flash point of a fuel is, the lower the temperature at which the fuel can form a combustible mixture. For example, gasoline has a flash point of -40 F, which means that gasoline can form a combustible mixture at temperatures as low as -40 F. Biodiesel on the other hand has a flash point of over 266 F, meaning it cannot form a combustible mixture until it is heated well above the boiling point of water. It is rare that fuel is subjected to these types of conditions, making biodiesel significantly safer to store, handle, and transport than petroleum diesel. In fact, the National Fire Protection Association classifies biodiesel as a non-flammable liquid. 3.7 Recycling: The use of used cooking oils as a biodiesel feedstock has increased their value significantly in recent years, making proper collection and recycling of these oils more cost effective, and lowering the volume of these oils destined for sewers and landfills. The waste cooking oil is generated from the fried food, which need large amounts of oil because it requires the full immersion of food at temperatures greater than 180 °C. Reuse of domestic oil has a high risk to the h ealth of consumers as depending on the type of food subjected to frying, “this absorbs between 5% and 20% of the used oil, which can increase significantly the amount of hazardous compounds that provide degraded oil to food”. 3.8 Waste Disposal and Byproducts The biodiesel production process results in two primary waste products: Waste water from the fuel washing process (approximately 1 gallon of water for every gallon of biodiesel). Send to the local wastewater treatment facility (with permission). The second product is glycerin which is drained off at the end of the fuel production process (approximately 1 gallon for every 3 gallons of biodiesel) . 23 4 4.1 BIODIESEL ECONOMY FROM WASTE OIL Economic Impacts of Biodiesel From an economic point of view; the production of biodiesel is very feedstock sensitive. From a waste management standpoint, producing biodiesel from used frying oil is environmentally beneficial, since it provides a cleaner way for disposing these products; meanwhile, it can yield valuable cuts in CO 2 as well as significant tail-pipe pollution gains. Any fatty acid source may be used to prepare biodiesel. Thus, any animal or plant lipid should be a ready substrate for the production of biodiesel. The use of edible vegetable oils and animal fats for bio diesel production has recently been of great concern because they compete with food materials. There are concerns that biodiesel feedstock may compete with food supply in the long-term. Hence, the recent focus is the use of non-edible plant oil source and waste products of edible oil industry as the feedstock for biodiesel production meeting the international standards. For example, the total production of oils and fats in the United States reached £35 billion in 2004. If this total amount were converted to biodiesel, only 5 billion gallons of biodiesel or about 8 percent of the diesel presently consumed would be produced. Therefore, other sources like algal oils will be required to satisfy this increasing demand. With cooking oils used as raw material, the viability of a continuous transesterification process and recovery of high quality glycerol as a biodiesel by product are primary options to be considered to lower the cost of biodiesel. However, there are large amounts of low cost oils and fats such as restaurant wastes and animal fats that could be converted to biodiesel. The problem with processing these low cost oils and fats is that they often contain large amounts of free fatty acids (FFA) that cannot be converted to biodiesel using an alkaline catalyst. Biodiesel is more expensive than petrodiesel, though it is still commonly produced in relatively small quantities (in comparison to petroleum products and ethanol). The competitiveness of biodiesel to petrodiesel depends on the fuel taxation rates and policies. Generally, the production costs of biodiesel remain much higher than those of petrodiesel. Therefore, biodiesel is not competitive with petrodiesel under current economic conditions. The competitiveness of biodiesel relies on the price of the biomass feedstock and costs associated with the conversion technology. Many alternative fuels have difficulty-gaining acceptance because they do not provide similar performance to their petroleum counterparts. Pure biodiesel and biodiesel blended with petrole um diesel fuel provide very similar horsepower, torque, and fuel mileage compared to petroleum diesel fuel. In its pure form, typical biodiesel will have energy content 5%-10% lower than typical petroleum diesel. However it should be noted that petroleum diesel fuel energy content can vary as much as 15% from one supplier to the next. The lower energy content of biodiesel translates into slightly reduced performance when biodiesel is used in 100% form, although users typically report little noticeable change in mileage or performance. When blended with petroleum diesel at B20 levels, there is less than 2% change in fuel energy content, with users typically reporting no noticeable change in mileage or economy. The injection system of many diesel engines depends on the fuel to lubricate its parts. The degree to which fuel provides proper lubrication is its lubricity. Low lubricity petroleum diesel fuel can cause premature failure of injection system components and decreased performance. Biodiesel provides excellent lubricity to the fuel injection system. Recently, with the introduction of low sulfur and ultra-low sulfur diesel fuel, many of the compounds which previously provided lubricating properties to petrodiesel fuel have been removed. By blending biodiesel in amounts as little as 5%, the lubricity of ultra-low sulfur diesel can be dramatically improved, and the life of an engine’s fuel injection system extended. Since biodiesel is a fuel which can be created from locally available resources, its production and use can provide a host of economic benefits for local communities. The community-based model of biodiesel production is particularly beneficial. In this model, locally available feedstocks are collected, converted to biodiesel, then distributed and used within the community. This model keeps energy dollars in the community instead of sending them to foreign oil producers and refineries outside the community. The peripheral benefits of this type of model are different for each case, but can include increased tax base from biodiesel production operations, jobs created for feedstock farming and/or collection, skilled jobs created for biodiesel production and distribution, and income for local feedstock producers and refiners. 24 Biodiesel feedstock can come from a variety of agricultural crops. When these crops are grown in a sustainable manner, using good stewardship practices, there are long term benefits to farmers, farming communities and the land. Many crops which yield oils used for biodiesel production c an be a beneficial rotation for other food crops, including soybeans when used in a traditional corn rotation, and canola when used in a wheat rotation. Using crops in rotation can improve soil health and reduce erosion. The overall impacts of growing energy crops are complex, with thousands of variables. However, the added value created for oilseed crops by the production of biodiesel is a tangible benefit for farming communities, and when coupled with sustainable farming practices can provide benefits to farming communities and the environment. Since there are multiple feedstocks from which to make biodiesel, plant operators can opt for the least expensive feedstock currently available, if they have a multiple-feedstock system. This flexibility makes producers less subject to price fluctuations. One example of this is noted by the prices of soybean oil. Its price has doubled in recent years, and is predicted to continue to rise according to a 2001 study by the U.S. Department of Agriculture. The study proje cts a total cash crop increase of $5.2 billion by 2010 — an average net increase to farms of $300 million per year — with soybean prices increasing 17 cents per bushel annually over that period. 4.2 The Glycerin By-Product: For every 10 parts of biodiesel produced, there is 1 part glycerin formed. Glycerin is becoming so abundant with increased biodiesel production that the demand for it has dropped, causing some people to have to pay to dispose of it. Here are some options for what to do with the glycerin (mo st ideas are to convert it into something more valuable to be sold). However, Crude glycerin is not a high value commodity 15 gallons of glycerin = $3 (excluding shipping). Crude glycerin from the biodiesel conversion process has three possible uses: Compost accelerator, Methane booster in anaerobic digesters, Soap production. A make-or-buy trade study on the costs and benefits of a do-it-yourself program. Components of program cost: Equipment, Accessories, Supplies, Oil Feedstock Costs, Utilities, Transpor t, Testing, Glycerin Disposal, and Labor. Figure 17: Payback period reduction through higher biodiesel production volumes 4.3 Biodiesel Program Cost Estimates Biodiesel processing equipment requirements include biodiesel processing equipment (heating, mixing), water supply, waste oil supply, clean drums (for strained oil, finished fuel, and glycerin), containers, beakers, buckets of various sizes for chemical pouring, waste glycerin, and waste oil emulsion, safety Equipment (Face shield, gloves, and apron), storage area for finished fuel, chemicals: KOH or NaOH, Methanol, Sulfuric Acid. Figure 22 summarizes the different sources used in biodiesel production using waste oil. 25 Figure 18: The routes to the production of alternative biodiesel diesels capable of replace petrodiesel 5 5.1 CASE STUDIES Case study: Daphne Utilities, Alabama The population of this area is 22,000. The project started and launched at 2006 by cooking oil collection program aimed to decrease the amount of oils going to the POTW, by collecting oil in consumer friendly areas. The amount of collected used oil 300‐500 gallons/month. The program was started with only a capital cost of ~$3,000 including recycling program and homemade biodiesel equipment, and B20 blended and used in their fleet of vehicles. There was a $10,000 annual fuel cost savings as well as a reduction of greases in the municipal waste water. The glycerin byproduct was used to make soap, which were their main marketing tool in schools. 26 5.2 Case study: Biodiesel Lebanon Nahr El Mot Industrial Zone T/F: 01 900654 VAT 1250006 - 601 TO WHOM IT MAY CONCERN Biodiesel-Lebanon is a private owned company specialized in Biodiesel production and Glycerin purification. It is the only Bio Fuels provider on industrial scale in Lebanon, located in the Industrial Area of Nahr El Mot, northern Beirut. We produce biodiesel out of used cooking oil collected from restaurants, hotels and kitchens across the country. We help the environment by preventing the liquid wastes to go in the sewage and therefore polluting the water streams, and by producing bio fuels which combustio n contains no mineral contaminants in the air. We have started the factory with top of the line equipments imported from the Netherlands and Argentina, back in 2007. Biodiesel-Lebanon has been so far dealing with some private gas distributors, and today w e are being approached by the Lebanese Ministry of Energy and Water in order to cooperate in terms of introducing Bio Fuels into the state official listings of fuels and possibly delivering our products for state power generation. Our capacity is 3 batches of 1mt per hour of ASTM Biodiesel and we extract Glycerol for purification using a distillation tower yielding 180 L/hr of USP Glycerin. Fady Faddoul Managing Director You may also check this link: http://mtv.com.lb/special%20reports/oil%20recycling 27 6 6.1 CONCLUSION AND RECOMMENDATIONS Conclusions Biodiesel is the best candidate for diesel fuels in diesel engines. It burns like petroleum diesel as it involves regulated pollutants. So it necessary to implement the use of biodiesel over the current petroleum and gasoline because of all the merit and advantages it brings forth to the table. In comparison to petroleum and gasoline, biodiesel hits its competitors in all categories of toxic substance emissions and poses close to no threat to the environment. What's more, instead of increasing the carbon dioxide levels in the atmosphere, the overall production and use of biodiesel consumes more carbon dioxide than it emits, thus making it a valuable tool in preventing global warming. By using biodiesel in the place of petroleum diesel, not only will we be helping the environment with a much better alternative, but we would be significantly reducing many health risks. The fact that most biodiesels are homemade means that by using more of it, the market of biodiesel would actually stimulate the economy, reducing a country’s dependence on foreign oil imports. In addition, the implementation of biodiesel is extremely easy and requires little or no modifications to the typical diesel engine, making it a very easy and smooth transition. When we talk about the pros & cons of biodiesel produced from waste oils, it is easy and clear to conclude that the advantages are extremely more than its disadvantages. They are very environmentally friendly, biodegradable and contribute to sustainability. The production of biodiesel from waste vegetable oil offers a triple-facet solution: economic, environmental and waste management. The new process technologies developed during the last years made it possible to produce biodiesel from recycled frying oils comparable in quality to that of virgin vegetable oil biodiesel with an added attractive advantage of being lower in price. Thus, biodiesel produced from recycled frying oils has the same possibilities to utilize. 6.2 Recommendations: Biodiesel could be manufactured from other feedstocks of low cost oils and fats such as restaurant waste and animal fats that could be converted into biodiesel. The problem with processing these lowcost oils and fats is that they often contain large amounts of free fatty acids (FFA) that cannot be converted into biodiesel using an alkaline catalyst. Important operating disadvantages of bio-diesel in comparison with fossil diesel are cold start problems and the lower energy content. This increases fuel consumption when biodiesel is used (either in pure or in blended form) in comparison with application of pure fossil diesel, in proportion to the share of the bio-diesel content. Taking into account the higher production value of bio-diesel as compared to the fossil diesel, this increase in fuel consumption raises in addition the overall cost of application of bio-diesel as an alternative to fossil diesel. Further experiments should be done in the lab such as producing the biodiesel from pure or waste vegetable oil and make it undergo under all the additional steps once the transestrification is completed as to get a biodiesel of high quality as for commercial biodiesel. In addition, further fuel analysis should conduct on biodiesel to get properties that match the standard values such as density, viscosity, heating value and oxidation stability. Moreover, further experiments of fuel analytics could be done to get other fuel properties as flash point, cloud point, cetane number, etc. and finally yet importantly, the further emission testing should be done on different engines using the biodiesel fuel to get results that show the reduction of emissions when using biodiesel as it said in theory. 28 7 REFERENCES:        https://en.wikipedia.org/wiki/Biodiesel http://daphneutilities.com/daphne/recycle_bio.htm http://www.uic.edu/classes/chem/clandrie/orgolabs/CASPiE/CASPiE_assets/biodiesel1_mo dule.pdf) Biodiesel Production from Waste Cooking Oil. Carlos A. Guerrero F., Andrés Guerrero Romero and Fabio E. Sierra National University of Colombia, Colombia. http://www.sciencedirect.com/.pdf Biodiesel from waste cooking oil via base-catalytic and supercritical methanol transesterification Ayhan Demirbas * Sila Science, Trabzon 61040, Turkey The Course handouts and lectures. (U.S. Department of Energy National Renewable Energy Laboratory, Biodiesel Handling and Use Guidelines) 29