A Review on Recent Advancement in Solid Waste Management Concept

Journal of Environmental Engineering and Studies Volume 3 Issue 2 A Review on Recent Advancement in Solid Waste Management Concept 1Prof. Manisha P Vashi, 2Kajal Anantbhai Desai 1 Assistant Professor, Water Resource Management, 2 ME, Environmental Engineering, Sarvajanik College of Engineering & Technology Email Id: [email protected], [email protected] Abstract Solid waste is the major concern observed now days in entire world. The reason for developed and under developing countries facing this problem is different. For developed countries it is due to excessive packaging along with high generation rate. While in developing countries improper handling and treatment is a major threat. The purpose of this paper is to focus on advancement in treatment options, handling and management of Solid Waste in recent times. Solid waste generation in metro cities found in 1995 was 0.64kg in Kanpur, 0.52kg in Lucknow, 0.4kg in Varanasi, 0.59kg in Ahmedabad and 0.44kg in Mumbai. Currently total solid waste generated in India is around 42 million tons annually. Waste generation varies from 200-600 kg/capita/day and collection efficiency ranges from 50-90%. Presently, advance treatment options provided for solid waste are: Incineration, Pyrolysis and vermin composting. Along with that reuse and recycling of waste materials also possess high opportunity. Segregation is still done by only rag pickers or scavengers at the disposal site only, which is highly hazardous to those people who involve in this and is also impracticable. The best option found to combat this problem is source segregation. The paper emphasizes on formal and organized system of segregation like segregation of wet waste, dry waste, plastic waste and hazardous waste, as per rule their generation because at the end of the cycle it becomes difficult to treat the solid waste because of its various characteristics. Keywords: Advanced Treatments; Collection efficiency; Developing Countries; Generation rate; improper handling; Segregation; Solid Waste Management INTRODUCTION Solid waste management is the biggest challenge now a days for any developing country due to increasing generation rate and conventional waste handling techniques. Solid waste is being generated on a daily basis in bulk. The sources of solid waste are organic domestic waste, some of the inorganic waste which we can say rubbish, toxic chemical waste from industrial plants, agricultural or field waste and biomedical waste. Proper solid waste management must be done to avoid the transmission of infectious diseases and thus to prevent the contamination of various environmental resources which are the lifeline of humans. 1 A general conventional practice involves collection of solid waste from localities by liable municipal authority, transfer to transport station, taking the waste for final disposal. For domestic or household waste no useful treatment option has been implemented to reduce either volume or strength of generated solid waste. Some common practices that could be done in order to improvise the system of waste disposal, it includes segregation of waste into biodegradable and non-biodegradable matter. Recyclable materials can also be set aside to be reused for other purposes after considerable treatment. These individual efforts bring a gradual shift Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 from inefficient segregation at disposal site to a well-managed source segregation. Solid waste is collected by private or public waste management companies. Mostly in Indian scenario collection and handling of solid waste is municipality’s liability. Local governments either have their own waste management sectors or they arrange contracts with public companies for certain period of time. Collection vehicles, frequency of collection and method of collection varies with type of area. After waste collection by the waste haulers, it is being sent to either a landfill site or a transfer station. It depends on distance of landfill site from collection are as well as on characteristics of the solid waste collected. If the waste is rich in recyclable material then before being pressed by a compactor in a landfill, a majority of trash is separated for recycling, and what is not recyclable goes in the landfill. Depending on the location, there might be several areas to which trash is transported. Where trash is sent depends on its proximity to the nearest landfill. If trash isn't collected by waste haulers, it's usually gathered by municipal haulers they send the collected trash to a transfer station if the nearest landfill is too far away. Transfer stations stores the trash as well as recyclable materials according to transport cycle. The station only serves as a kind of way station on the waste's journey to the landfill. After the waste leaves the transfer station ultimately it requires treatment and disposal. Most commonly approached option for waste disposal in India is land filling but as the population, land greed and public attitude towards NIMBY concept has been growing it has become difficult to acquire new land for waste disposal. It is necessary to develop new and feasible treatment options for solid 2 waste treatment. Reuse, recycling and recovery these 3R concepts are of major interest in this new era. Improper waste disposal and management can cause serious deterioration of various environmental attributes such as soil, water and air, interfere with biological waste treatment processes, occupies valuable landfill space, pollute water bodies and respective beaches. It also injures sanitation workers. Some products are toxic in nature and may cause noticeable harm like: paint, medicines, auto fluids, E-waste, lead batteries. Such household products become hazardous when used, stored or disposed of incorrectly. If it is disposed of with regular household waste and they end up in landfills where they may seep into the soil and contaminate the groundwater. Flushing these types of materials into a toilet or drain can interfere with waste treatment processes, contaminate the effluent that runs into the ocean and affect the bio solids used as fertilizer. It also covers the upper surface of water body thus decreases DO solubility and harm the aquatic ecosystem. Waste left in the street typically enters storm drains and washes out near waterways. REASONS FOR INEFFICIENT SYSTEM Disinterest of Local Government In most of the Indian cities it is responsibility of Municipal Corporation to manage the waste but the municipality is not able to handle the task properly. Though the city is providing high capital for cleanliness and sanitary section, due to improper management the hygiene is not up to the mark. Most of the fund is being wasted in paying the rag pickers and haulers who are not working efficiently. It is due to lack of motivation to workers. Along with that the personnel involved with this job, delegate whole the work to sanitary engineers who lack in experience Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 as well as knowledge thus cannot manage the system properly. To combat this problem Municipal solid waste (management & handling) Rule, 2000 has been amended which says that Municipal Corporation of particular city is solely liable to manage and handle the solid waste. The guidelines have become stringent for the local authority. Lack of Community Awareness Community participation has a direct impact on efficient SWM. Generally what people think is hygiene and sanitation is municipality’s liability only. Especially in villages and towns with less literacy, they are not aware of ill effects of improper waste handling and management. Yet, the municipal authorities have failed to mobilize the community and educate citizens on the rudiments of handling waste and proper practices of storing it in their own bins at the household-, commercial and institutional-level. Due to inconvenience of the facility of waste collection from the source, citizens are dumping waste on the open spaces, streets, in drains, and in water bodies like lake, river pond in the nearer area creating unhygienic situation. People believe that municipality would be picked up the waste thrown by them on the streets during street sweeping. This people mind set and lack of awareness is primarily responsible for the inappropriate waste management in the country. Which can only be resolved with proper education, training, awareness programs. This kind of sessions could be held by both the municipality and informal sectors working in the area like NGOs. People used litter the streets with a though that it will be cleaned by the sweepers. NEED OF REVISED STRATEGY A conventional solid waste management practice of Indian cities are having many back logs which leads to inefficient system, street littering, odor problem Main drawbacks of conventional waste handling practice are: 3 1. No Storage of Waste at Source 2. No segregation of waste at source 3. No Primary Collection system for collection of waste from source of generation 4. Irregular and improper Street Sweeping 5. Open intermediate Waste Storage Depots 6. Open and inappropriate hauling vehicle 7. Methods used for loading –unloading waste 8. Processing of Waste 9. Disposal of Waste The objective of review is to focus on solid waste services provided through trash holder, transfer station, recycling facilities and MSW landfill. If the provided services are adequate, sustainable and compatible with state policies and goal no need to worry. The typical services available for solid waste includes waste collection transport to transfer station, segregation, reuse, recycling at disposal site. There is plenty of other disposal option available for treating the solid waste like composting, incarnation, plasma gasification, and pyrolysis but, still due to solid waste management crisis in India, its ultimate impact on environment, Public health and quality of life. As per the Schedule-I of municipal solid waste (management & handling) Rule,2000 the local bodies are require to set up waste processing and Disposal facilities and improvement of existing landfill site before December 31,2003.After sometime It has been observed that Schedule-I is not compiled by many of local bodies and difficulties in finding waste disposal sites. As per Schedule-II guidelines are provided for segregation, collection, storage and transport of waste and other awareness programs are attempted for segregation of Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 waste. However only few cities/towns are made efforts. Further issue generated due to high cost and unavailability of technical assistance to local bodies result in could not improve undertaking landfill site and preparing new site of landfill for further use. Majority of waste disposal sites are open dumps. At only one or two place processes plant, waste to energy plant and RDF plants are set up. There is no involvement of local body due to high expenditure. After struggling with the battle of growing of solid waste, new solid waste management Rules, 2016 has notified by the Ministry of environment and forests with clear duty assign to various waste producer. Ministry says that estimated 62 million tons of waste a year is not fully collected or treated and it will go up to 165 million tons in 2030, and it will results in dramatic episodes of air and water pollution from mountain of garbage as seen in Mumbai and Bengaluru in recent time. CONVENTIONAL METHODS OF TREATMENT India is the second largest nation in the world, with a population of 1.21 billion, accounting for nearly 18% of world’s human population, but it does not have enough resources or adequate systems in place to treat its solid wastes. For the management of solid waste and to decrease its hazardous effect to human health and environment the proper management is necessary and aspects are needed for treating the wastes. There are so many methodologies which can be used for management and treatment of solid waste also disposal could be a good option for that. Different kind of methodologies which are recently used for management of solid waste could be described as below: ● Dumping into the sea 4 ● ● ● Sanitary Landfills Incineration Composting Dumping into the Sea In the past, communities around the globe used the ocean for waste dumping, which also include some chemical and industrial wastes, radioactive trash, munitions, sludge from sewage. Wastes were frequently discarded in ocean waters based on mentality that ocean waters had an unlimited capacity to mix and scatter wastes .Refuse is taken in barges sufficiently far away from the coast (15-30 km) and dumped there. It is very costly and not environment friendly. . Sanitary Landfilling of Solid Wastes United Nations Environmental Program (UNEP) defines sanitary land filling as the proper disposal of solid wastes on land in well-defined manner that contact between waste and the environment is considerably reduced and wastes are stored in a wellmanaged area. The purpose of Sanitary landfills (SLFs) is to segregate wastes from the environment and leave them harmless through the different biological, chemical and physical treatments. UNEP gives three basic orders to be satisfied design of SLF: a) Compaction of the wastes, b) Daily covering of wastes (with soil or other material) and c) Control and prevention of negative impacts on public health and environment. On the hierarchy of waste management, sanitary landfilling is expanded into three different categories: a) SLFs recovering and using methane (CH4) b) SLFs recovering and flaring CH4 c) SLFs without any CH4 recovery SLFs are differentiate depend upon their capacity to manage and stop harmful Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 impacts on environment with climate change perception. They dwell in the three points after WTE technologies on the hierarchy of solid waste management. One is to managing CH4 generated during anaerobic digestion of organics dictates where all type of landfill is placed on the waste management hierarchy. Organic waste in landfills treated by both aerobic and anaerobic digestion it depend upon the oxygen availability. Majority of the waste on the top undergoes aerobic digestion due to greater oxygen availability. Waste which is inside SLFs undergoes anaerobic digestion due to reduced oxygen availability. The final gaseous product of aerobic digestion is CO2, which results in a net zero emission. However, the final gaseous product of anaerobic digestion is CH4, which if captured can be used as a fuel, generating renewable energy and converting the carbon in CH4 to CO2, thus resulting in a net zero emissions. In a business as usual scenario (BAU) in India and elsewhere, the CH4 is let out into the atmosphere and not captured. CH4 is a greenhouse gas (GHG), with twenty one (21) times more global warming potential than CO2 (over a long time period). Therefore, every CH4 molecule released from a landfill has 21 times the potential to warm the planet than CO2. Thus, capturing and flaring CH4 is environmentally preferred to sanitary landfilling without capturing CH4. However, landfilling of materials should be the last option considered for disposing wastes in an integrated waste management system. Also, “currently, the implementation and practice of sanitary landfilling are severely constrained in economically developing countries (like India) by the lack of reliable information specific to these countries”. Engineered Landfills of Solid Wastes In this type of landfill bottom of the ditch is ruled with impervious fabric to avoid the leachate from contaminating groundwater. A well designed plan has leachate 5 collection mechanism after collecting leachate it is treated and then disposed off. Incineration of Solid Waste This method suited for combustible wastes and wastes which cannot be treated and hazardous is burnt. Suited in crowded cities where sites for land filling are not available but operation and construction cost is very high. It is sometimes used to reduce the volume of solid wastes for land filling. Primary chamber – designed to facilitate rapid desiccation of moist refuse and complete combustion of refuse and volatile gases. A ledge or drying hearth is provided for this purpose. Secondary chamber – between the primary chamber and the stack – temperatures above 700º C and all unburnt and semi burnt material are completely burnt here. Composting Composting is a well define tool known in India since the times of immemorial. Composting is the decay of organic matter by microorganism in some appropriate condition of environment. Composting mostly needed warm, moist, aerobic and anaerobic environment. Farmers in all over the world have been using this composting technique for their cow dung waste and other agro-waste made out compost from these types of waste. It has been observed that the compost made out of urban mixed waste is found to be of higher nutrient value as compared to the compost made out of cow dung and agro-waste. Therefore, composting of municipal solid waste is, the most easy and economic process for treating the organic portion of MSW. In India Full-scale commercially viable composting technology has already established and also in use by several towns and cities. Its application to farm land, tea gardens, fruit orchards or its use as soil conditioner in parks, gardens, agricultural lands, etc., is however, limited on account of poor marketing. Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 NEW CONCEPTS OF TREATING SOLID WASTE ● Pyrolysis, ● Pyrolysis with gasification ● Plasma pyrolysis, ● Production of refuse derived fuel (rdf) ● Grinding and discharging into sewers ● Salvaging ● Fermentation and biological digestion ● Reuse ● Recycle ● Recover Pyrolysis/Gasification, Plasma Pyrolysis Vitrification Pyrolysis gasification treatment are wellknown for homogenous organic material like wood, pulp, etc., while plasma pyrolysis process is a comparatively new technology for discarding of mainly hazardous wastes, radioactive wastes, etc. Poisonous materials get encapsulate in major mass, which is comparatively much safer to manage than gasified and incinerated ash. These are now being an attractive choice for removal of MSW also. In all these process, as well net power renewal, suitable devastation of the waste is also ensured. These methods have an edge on incineration. This method produces fuel gas/fuel oil, which restore fossil fuels. NO and SO gas emissions do not occur in normal operations due to the lack of oxygen in the system. It is a capital and energy intensive process and net energy recovery may suffer in case of wastes with excessive moisture and inert content. High viscosity of Pyrolysis oil maybe problematic for its transportation and burning. Concentration of toxic/hazardous matter in gasifier ash needs care in handling and disposal. Production of Refuse Derived Fuel (RDF) or Pelletization It is principally a processing method which can be used for mixed Municipal solid waste, which can be extremely efficient for thermal processes like incineration or 6 industrial furnaces in preparing of enriched fuel. The RDF pellets can be suitably stored and transferred and it can be used as a coal alternate at a lesser price. As pelletization involves important solid waste segregation operations, it provides a superior chance to eliminate environmentally damaging materials from the arriving waste previous to incineration. The method, however, is energy rigorous and not suitable for wet municipal solid waste during monsoon season. It requires a great care and safety while production, storage, transportation and usage. If RDF pellets are contaminated by toxic/hazardous material, the pellets are not safe for burning in the open or for domestic use. Waste to Energy Combustion (WTE) Waste-to-Energy combustion (WTE) is defined as a method of controlled breaking of material. This involve an enclosed apparatus to thermally breakdown combustible municipal solid waste and last residue is ash which have no calorific value but can be use in road making and other resulted product can release energy it can be used in replacement of fuel. Even though both WTE combustion and RDF combustion have same objective of reduce its volume and made out or extract useful value from waste of Municipal solid waste. The energy generated after this only adds value to this process. Thermal wastes to energy process are the only solutions to manage mixed wastes. The way mixed wastes are processed all the impurities release from the waste into environment and in it will pollute air, water and land resources. By aerobic composting of mixed wastes, the impurities like heavy metals and other impurities leak from the compost. The bottom ash from WTE combustion contains nothing but inert inorganic materials and minerals which could be used to make bricks and other construction material. The fly ash from WTE contains Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 pollutants from the input stream and needs to be disposed of in sanitary landfills. By controlling the types of materials fed in to the boiler, European and Japanese WTE plants are known to have achieved nearly zero emissions in the fly ash too. Mechanical Biological Treatment (MBT) On an average, 6% of MSW collected is composted in mechanical biological treatment (MBT) plants across India. MBT is the most widely employed technology to handle MSW in India. At present, there are more than 70 composting plants in India treating varied Municipal solid waste SW, most of them situated in the states of Himachal Pradesh, Maharashtra, Orissa and Chhattisgarh. More than 26 innovative plants are projected in diverse cities and towns across India. Out of the 57 cities which generate MSW above 200 TPD, 38 cities have composting plants, which treat more than 4,361 TPD of MSW. Almost all biological services hold mixed municipal solid wastes. The only known facility which handle source divided organic wastes. While almost all these facilities carried out mixed solid wastes, the portion of refuse which go to the landfill is extremely high. Reuse- Recycle- Recover The 3R concept has gained a lot of importance with time. Reuse comes first in the hierarchy of waste management as it does not require much expense plus efforts. Only the thing which is must for the reuse approach is proper segregation. If reusable material is separated from other scrap matter that it can simply be washed or cleaned and can be used for the same or any other purpose. Ultimately reuse reduces the cost for waste disposal as the quantity has been reduced. With that if the waste matter is being used as a raw material in some other process that it also cuts the cost for raw material purchase. Natural resources being used as raw 7 material are also saved with this approach. Recycle comes second under the hierarchy of waste handling as this process needs considerable efforts, time, expense and treatment. Recycling is transformation of waste material into the same or new useful products. It is important to have a market for recycled goods. If the sale of recycled goods is not motivated then whole the system is failure. Recovery comes into picture when the waste is rich in valuable metals and other recoverable material. The only drawback of recovery system is it is highly expensive. From installation to operation it requires good investment, thus it is not practicable for small scale waste station. Now a days a new concept has been added to 3R which is Rethink. It emphasizes that everyone must think again before disposing the material which they consider as waste. If is useful for any other purpose anyone else then it should be considered useful once again. CONCLUSION There is a vast scope for improvement. Firstly segregation of organic and inorganic waste at the source must be done by the residents. Awareness programs must be held by the local authorities for the same. With educatory sessions legal binding is also required to strictly follow segregation strategy. Along with that recyclable and hazardous waste from households must be collected separately to avoid contamination of whole the bulk and thus to reduce the load on the treatment plants. Conventional practices and strategies must be revised and implemented in order to manage increasing load of solid waste. Open intermediate waste storage depots and transfer vehicles spreads considerable amount of waste to the surrounding area which spreads diseases and creates Page 1-8 © MAT Journals 2018. All Rights Reserved Journal of Environmental Engineering and Studies Volume 3 Issue 2 unhygienic conditions prone to health hazards. Solid waste treatment methodology must be equipped with efficient technology. Like conventional method of sanitary landfill must be provided with methane gas recovery facility. Incinerator with heat recovery system, vermin composting and plasma pyrolysis with least possible residues. REFERENCES 1. R.K.Annepu, Sustainable Solid Waste Management in India, Earth 8 2. 3. 4. 5. Engineering Center Report 2012 P. U. Asnani, solid waste management, India Infrastructure Report 2006 Annual Report (2001-2002), Municipal Solid Waste (management & Handling) Rule, 2000, CPCB (Ministry of Environment & Forest),1-3 Central Pollution Control Board, India. Plastic waste management: Environmental issues and Challenges. Ministry of Urban Development(MOUD), Government of India. Solid Waste Management Manual, New Delhi: Ministry of Urban Development, 2000. Page 1-8 © MAT Journals 2018. All Rights Reserved