Slurry

RESUMEN Durante la Zafra 16-17 se visitaron seis ingenios azucareros para caracterizar la forma de preparación de semilla (slurry) de cristalización, comparar las distintas prácticas y determinar cuáles son las mejores para generar un método óptimo que asegure la calidad en la semilla. Se analizaron las variables en este proceso: tipo de molino, tipo de azúcar, tipo de alcohol, tamizado de azúcar, cantidad de azúcar y alcohol agregados al molino, tiempo de molienda, etc. Se efectuó un análisis cristalográfico a la semilla en los ingenios, esto permitió evaluar el impacto en la calidad que tiene cada una de las variables mencionadas. Entre otras cosas, se determinó que el mejor desempeño lo tiene el molino de bolas horizontal, ya que permite un tamaño de cristal entre 5 y 10 µm, un coeficiente de variación (CV) menor a 31% y una morfología uniforme de los cristales. Un análisis de la " maduración " demostró que la misma representa un 4% de disminución del CV y además mejora la curva de distribución de tamaños. ABSTRACT Six sugar mills were visited during the Harvest of 16-17 to characterize the seed (slurry) preparation method used in crystallization, to compare the different practices and to determine which are the best ones to generate an optimum method that assures the quality in seed. The variables in this process were analyzed: type of grinding mill, type of sugar and alcohol, sugar sifting, amount of sugar and alcohol added to the grinding mill, milling time, etc. A crystallographic analysis on seed was performed in the mills, which allowed to evaluate the impact on the quality of each of the mentioned variables. Among other things, it was determined that the horizontal ball mill has the best performance, because it allows a crystal size between 5 and 10 µm, a size spread (CV) less than 31% and a uniform morphology of the crystals. An analysis of the "maturation" showed that it represents a 4% decrease in CV and also improves the size distribution curve. ANTECEDENTES En la industria azucarera se utilizan varios métodos para preparar semilla. Por ejemplo, se tiene la formación por medio de rompimiento mecánico de azúcar suspendida en alcohol dentro de un molino de bolas, también se puede obtener por la mezcla de azúcar pulverizado tipo fondant con alcohol y un tercer método para la preparación implica utilizar medios fisicoquímicos, en el cual la semilla se forma por el enfriamiento rápido de una solución sobresaturada de azúcar al verterle un solvente en donde el azúcar es insoluble y se encuentra a menor temperatura.

A separation/enrichment procedure has been developed for the determination of selenium in garlic and onion samples by electrothermal atomic absorption spectrometry (ET-AAS) as a slurry sampling after preconcentration with 3,3-diaminobenzidine (DAB) reagent on the activated carbon. The influences of pH, time, amount of carbon and complexing reagent were outlined. The effect of acids used in the digestion of samples was also studied and compared. Selenium level was found to be 0.024 lg g À1 for onion (n = 5; LOD -0.5 lg L À1 ; LOQ -1.7 lg L À1 ) and 0.015 lg g À1 for garlic (n = 5; LOD -1.3 lg L À1 ; LOQ -3.3 lg L À1 ). Three different samples of garlic were analyzed by k 0 -instrumental neutron activation analysis (k 0 -INAA) at the Jozef Stefan Institute (JSI). The data obtained by k 0 -INAA show that the content of selenium overlapped the results obtained by ET-AAS.

This paper presents the results of technical and economic studies in order to evaluate, in the French context, the future production cost of electricity from IGCC coal power plants with CO 2 capture and the resulting cost per tonne of CO 2 avoided. The economic evaluation shows that the total cost of base load electricity produced in France by coal IGCC power plants with CO 2 capture could be increased by 39% for 'classical' IGCC and 28% for 'advanced' IGCC.

The present article describes a method of preparation coal-water slurry using a high speed mixer-disperser (HSMD).The method is based on the multiple impacts in a liquid media by dispersing elements in the appearance of cavitation effects. Considering the design features of a high-speed mixer-disperser it was found that the processing of coal-water slurry increases their stability due to particle size deceasing.

Production of biogas by anaerobic digestion process is not a new concept. Biogases have been produced since olden days but the matter of concern is the amount of biogas being produced is not always impressive with respect to economy of the process. So there is necessity of maximising biogas yield for improving plant feasibility and also to improve the economy of process. Since, the production of biogas by anaerobic digestion method is highly dependent on bacterial growth, in this study the role of catalysts on bacterial growth and ultimate yield of biogas have been presented. This paper also shows how different catalysts behave on production of biogas at different slurry and catalyst concentration. The main motive and aim behind this work is to find optimum conditions for maximum biogas yield, so that these findings can be helpful for producing biogas by anaerobic digestion process which will somewhat help in reducing the global energy crisis and also reduce the pollution problem.

Fertilization with animal residues together with no-tillage is being widely used in dryland Mediterranean agriculture. The aim of this work is to assess the potential impacts of these combined management practices on oribatid mite species, and to evaluate their potential use as bioindicators of soil disturbances. From an experiment established ten years ago, eight fertilization treatments (including minerals or pig slurries), all combined with minimum tillage (MT) and no-tillage (NT), were studied. Four of these combinations were sampled three times during the winter cereal cropping season. The rest, and a neighbouring oak forest, were only sampled close to the end of the season (May). In total, 34 oribatid species and 4140 individuals were recovered. Oribatid abundance responded positively (p < 0.05) to the reduction of tillage intensity (NT) and marginally (p < 0.1) to slurry fertilization at sowing (close to maximum legislation allowed rate: <210 kg N ha−1 yr−1). At this slurry rate, Shannon index of diversity varied through the season, and was higher in May in MT than in NT plots. The Berger–Parker index of abundance signals plots without slurries as the most disturbed (compared with the forest). Nitrogen slurry over-fertilization reduced abundance of Oribatula(Zygoribatula) connexa connexa , but the impact on the most relevant species depended on the tillage system: Epilohmannia cylindrica cylindrica dominated in MT plots; under NT it was balanced by Tectocepheus velatus sarekensis and Passalozetes (Passalozetes) africanus. Scutovertex sculptus is also very negatively affected by tillage. Oribatida are a good target for the biological indication of soil disturbances associated to agricultural management

Tillage and slurry over-fertilization affect oribatid mite communities in a semiarid Mediterranean environment.

Red mud waste is generally transferred to the storage area in a slurry form with solids content varying from 15 to 40%. Due to arise of a variety of environmental and climatic conditions in the due course of time, settling behaviour of particles as well as properties of settled particles changes. Thus, understanding of the settling behaviour of waste particles becomes essential after disposing the waste into the pond. In addition, studies related to the settling behaviour of particles become important during the extraction of alumina from bauxite ore (i.e. in settlers). In the present study, efforts are made to investigate the settling behaviour of red mud waste particles when exposed to different aqueous environmental conditions. For testing purpose, a series of differential free swell tests were conducted considering aqueous environmental conditions such as tap water, distilled water, kerosene, NaCl solutions of 1.71 and 3.42 M, and HCl solutions with a pH range from 1 to 4, respectively. In addition, efforts are also devoted to characterizing the post-exposed sediment samples to ascertain possible changes in the mineralogical, morphological , and elemental compositions of the particles. Results reveal that aqueous environment has a considerable effect on the settling behaviour of particles, while the effect of pH found to be trivial. The analyses of characterization studies disclose a marginal to considerable changes in elemental, phase compositions and morphological characteristics of the post exposed particles.

One of the possible utilisation methods for organic wastes is anaerobe decomposition (fermentation). The main product of this process is biogas which is usually used for energy purposes due to its composition (mainly methane and carbon dioxide). The residual solid material after fermentation can be used as soil conditioner.

Lab-scale fermentation can be carried out using the “VDI 4630 – Fermentation of organic materials Characterisation of the substrate, sampling, collection of material data, fermentation tests” standard. Based on the conditions described in the standard, a small-scale low-budget reactor system were prepared. The temperature during the holding time was controlled with water bath and the gas production was determined with fluid displacement method. A peristaltic pump was used for the recirculation of the gas to mix the base material. Furthermore, the temperatures of the environment, the water baths and the inside of each reactor was automatically registered on a data collector.

The mechanisms and specific sources of priming effects, i.e. short term changes of soil organic matter (SOM) decomposition after substance addition, are still not fully understood. These uncertainties are partly method related, i.e. until now only two C sources in released CO 2 could be identified. We used a novel approach separating three carbon (C) sources in CO 2 efflux from soil. The approach is based on combination of different substances originated from C 3 or C 4 plants in different treatments and identical transformation of substances like C 3 sugar (from sugar beet) and C 4 sugar (from sugar cane). We investigated the influence of the addition of two substances having different microbial utilizability, i.e. slurry and sugar on the SOM or/and slurry decomposition in two grassland soils with different levels of C org (2.3 vs. 5.1% C). Application of slurry to the soil slightly accelerated the SOM decomposition. Addition of sugar lead to changes of SOM and slurry decomposition clearly characterized by two phases: immediately after sugar addition, the microorganisms switched from the decomposition of hardly utilizable SOM to the decomposition of easily utilizable sugar. This first phase was very short (2-3 days), hence was frequently missed in other experiments. The second phase showed a slightly increased slurry and SOM decomposition (compared to the soil without sugar). The separation of three sources in CO 2 efflux from grassland soils allowed us to conclude that the C will be utilized according to its utilizability: sugarOslurryOSOM. Additionally, decomposition of more inert C (here SOM) during the period of intensive sugar decomposition was strongly reduced (negative priming effect). We conclude that, priming effects involve a chain of mechanisms: (i) preferential substrate utilization, (ii) activation of microbial biomass by easily utilizable substrate (iii) subsequent increased utilization of following substrates according to their utilizability, and (iv) decline to initial state. q

This article contains a verbal and mathematical description of the drying process inside ATM-52 spray dryer for ceramic paste production. Through the application of a modeling methodology, it was defined as an objective to be able to describe, by means of a phenomenological basis, the temporal variation of humidity in the outlet stream of the ATM-52 spray dryer. This variable is the most critical in the process and it’s the most fluctuating to measure in real time and only laboratory methods are available to obtain measurements. To achieve the objective, a series of assumptions were made, allowing to describe the model by a set of differential ordinary equations, The most important assumption is that the mass transfer phenomena are significant when streams flow is in co-current. Once the set of equations were obtained, through physical-chemical relations of the process, parameters values were assigned and computational verification was applied. The model was validated using the values in the steady state obtained from the real process.