Degradation Of Solid Waste Research Articles

Assessment of Landfill Odorous Gas Effect on Surrounding Environment

Landfill odorous gas emission has been a serious environmental problem, especially for the residents or passersby on the road near the landfill. In this paper, in situ monitoring and the numerical CALPUFF model were adopted to analyze the odor nuisance problem caused by municipal solid waste (MSW) degradation in a large landfill. The static chamber technique was used to measure the odorous gas emission rate on the working area, temporary cover area, and final cover area of the landfill during Dec. 2016 and Apr. 2018. The results showed that the emission rate of H2S on the working area varied from 0.003 mg/m2/min to 0.98 mg/m2/min, and it was positively correlated with the ambient temperature. The emission of H2S varied between 0.125 kg/h and 1.09 kg/h on the working area, and it varied between 9.2 × 10−6 kg/h and 6.8 × 10−4 kg/h on the temporary cover when considering the impact of the holes in a high‐density polyethylene (HDPE) membrane, and it was negligible on the final cover. The contribution rates of H2S emission in the whole landfill were 90.79%∼98.59% and 0.0008%∼0.52% for the working area and the temporary cover area, respectively. The numerical simulation showed that wind velocity and gas emission rates were the critical factors that affect odor dispersion. To limit the H2S‐influenced area within the landfill site, proper engineering measures should be taken to ensure the H2S emission rate of lower than 15% of its original value.

The effects of Insects on the Physicochemical Characteristics During Composting

Insects have a vital role in solid waste composting process. Insects are detritus feeders that enhance changing the physical and chemical properties of decomposed materials during composting processes. This behavior makes insects excellent organisms in recycling of organic matter. The present study assesses the success of insects’ population in relation with the degradation of solid waste. The study was carried out in the glass house facility of the College of Science, Salahaddin University in Erbil City, Kurdistan region of Iraq, using household organic waste. During composting process, three stages of lifecycle of insects were observed and recorded. The total number of insects reached to 1268 individuals, belonging to the orders Coleoptera and Diptera, class Insects. Diptera individuals were the most abundant insects with 95.4% of the total belonged to four families (Muscidae, Calliphoridae, Ulidiidae and Milichiidae). Coleoptera individuals represented 4.6% of the total number, belonging to three families (Promecheilidae, Staphylinidae and Salpingidae). The measured physicochemical characteristics of the compost included: pH, EC, moisture, total organic carbon, total nitrogen, total phosphorous and organic matter. The pH value of the composts ranged from 7.79 to 7.97. Organic carbon content and organic matter content ranged from 20.16 to 26.99 % and 34.67 to 46.23 %, respectively. It can concluded that household waste compost is not just a waste but has the potential to be transformed into a good quality organic fertilizer through composting. Composting can convert solid organic waste into a valuable added material.

Estimation of heat generation and consequent temperature rise from nutrients like carbohydrates, proteins and fats in municipal solid waste landfills in India

The heat generation and temperature rise due to the anaerobic degradation of municipal solid waste (MSW) for selected landfills across India have been estimated in this paper. MSW was quantitatively characterized into carbohydrates, proteins, fats using landfill degradation and transport (LDAT) model equations' and the physical composition of MSW. The heat released due to the breakdown of per kg of carbohydrates, proteins, fats were calculated using chemical equations involved in the anaerobic degradation process. The heat released per tonne of MSW degradation and temperature rise for selected cases was calculated. Moisture content and carbohydrates percentage were crucial parameters in estimating the heat generation as Mavallipura landfilled MSW having 43% carbohydrates and moisture content of 17% released maximum heat of 1116.81 × 103 kJ/t of MSW and Pirana landfill MSW having 12.98% carbohydrates and moisture content of 29.03% released minimum heat of 391.82 × 103 kJ/t of MSW. This generated heat may cause several issues, such as landfill fires, temperature rise in the surrounding areas of landfill, air pollution leading to global warming and other environmental issues. The heat generated from the biodegradation process is a renewable energy resource that can be systematically extracted from the waste mass and used for direct heating purpose in nearby facilities or for augmenting industrial processes having suitable technologies like combined heat and power gas engines, geothermal heat extraction system, etc. This study concludes that the total quantity of heat released depends on the quantity of carbohydrates present in waste and not on total organic content.

Microbial valorization of solid wastes from a recirculating aquaculture system and the relevant microbial functions

This study was performed to establish valorization technology for solid wastes from a seawater recirculating aquaculture system (RAS) by using beneficial microorganisms. An efficient microbial agent (KBM-1) was selected based on the degradation activity of the RAS solid wastes (20% slurry) in a lab-scale reactor system considering the removal rates of chemical oxygen demand, solid material, total nitrogen, ammonium-N, and nitrate-N and the production of organic acids as electron donors for denitrification. The microbial consortium KBM-1 was particularly efficient in the removal of ammonium-N and nitrate-N with removal efficiencies of 42% and 50%, respectively, in eight days and in the rapid production of organic acids (230 mg L−1, 3.5 mM, 0.018 kg m−3 d−1) after two days. There was a concomitant removal of NO3--N (41%, 0.005 kg N m−3 d−1) after two days when a significant production of organic acids occurred. Comamonas sp. was a dominant genus after eight days in all treatments. The level of nitrate-N in the treatments with KBM-1 decreased by 50.4% after eight days, as opposed to that of the control sample (27.7%), indicating the potential denitrification activity of Citrobacter freundii and Comamonas sp. The bioaugmented species (Sporolactobacillus inulinus, Lactobacillus mali, Lactobacillus casei, and Clostridium tyrobutyricum), constituting 41% of the total communities, appeared to facilitate the growth of indigenous microbial communities that were involved in the degradation (hence valorization) of solid wastes (mostly remaining fish feed and fish feces) into simple metabolites (organic acids and inorganic materials such as ammonium, nitrite, nitrate, and CO2). The simultaneous generation of organic acids through the valorization of solid wastes and their subsequent reuse in the denitrification of an RAS biofilter system can provide a significant contribution to the eco-friendly management of RASs and provide meaningful economic merit to the solid wastes of RASs.

Assessing pretreated municipal solid waste degradation by BMP and fibre analysis

Landfill continues to be the major method of Municipal solid waste (MSW) disposal in the UK and many other countries despite considerable efforts to limit its use. The EU Landfill Directive requires, amongst other things, that waste is treated to reduce its biodegradability prior to disposal to landfill. This pre-treatment is often achieved through what is generically termed mechanical-biological treatment. Predicting the biodegradability or degradation potential of these pre-treated wastes is important for the long term management and aftercare of landfill sites. To address this, a series of biochemical methane potential (BMP) tests have been undertaken to characterize the anaerobic biodegradation potential of two mechanically biologically treated (MBT) waste samples in terms of biogas yield, solids composition (loss on ignition, total carbon, cellulose, hemicellulose and lignin contents), and assessment of leachate characteristics during the biodegradation process. Experimental results from a long term study of MBT wastes treated to different standards are analyzed and compared. The relationship between biogas potential and solids composition was investigated, and carbon and nitrogen mass balances are discussed. The biogas potential was shown to correlate well with the ratio of cellulose plus hemicellulose to lignin, loss on ignition and total carbon content of the waste indicating a clear link between these parameters. The results indicate that solids composition of MBT wastes may provide a useful indication of the biodegradation potential. The mass balance indicates that a large proportion of carbon and nitrogen remain locked up in the waste material and is not released.

Chemical Stability and Maturity of Compounds from Organic Solid Waste Treatment

Composting is a recycling method based on biological degradation of organic solid waste (OSW) by microorganisms under aerobic conditions, resulting in a stable and mature organic compound that can be used as organic fertilizer in agriculture. Several countries have invested in this technology as part of urban solid waste management, since it is considered simple and inexpensive, provided there are parameters controlled during the process such as temperature, humidity, pH, carbon / nitrogen ratio and particle size. The composting process in the reactor system presents some advantages when compared to the traditional process in piles or ponds, as the requirement of smaller area and labor. The objective of this work was to evaluate the chemical stability and maturity of compounds from organic solid waste treatment by composting process in a reactor system. The reactor was constructed and filled with 60 kg of material, being 58% of OSW, 28% of Wood waste-sawdust and 14% of dry leaves. To evaluate the chemical stability of the compound the following parameters were monitored for 120 days: Temperature (°C); pH in 0.01 molL-1 CaCl2 solution; moist at 65°C; carbon/nitrogen Ratio; cation exchange capacity (CEC mmol kg-1); Total Organic Carbon (TOC) and CEC/TOC ratio. Toevaluate the maturity of the compound the following parameters were monitored: Germination index (GI); Electric conductivity (EC); Spectroscopic characterization of humic acids in the ultraviolet-visible region (UV-Vis); Spectroscopic characterization of humic acids by Fourier transform infrared spectroscopy (FTIR) and ash content. It was observed that after 90 days the compound presented stability, with reduction of temperature, moist and Carbon / Nitrogen ratio, increase of pH, CEC and CEC / COT ratio; however, the maturity of the compound was reached at 120 days of the composting. The compound reached stability and maturity at the end of the composting process (90-120 days), indicating that it could be used as soil corrective in agriculture.KEY WORDS: organic solid waste, composting, stability, mat

Amelioration of Physico-Chemical Parameters and Phytotoxicity of Landfill Leachate by Microbial Degradation

Objective: To understand the effect of microbial treatment on physico-chemical parameters and phytotoxicity of leachate arising from degradation of municipal solid waste. Methods and statistical Analysis: Landfill leachate samples were collected from a municipal landfill site in Mumbai, India at different phases of its degradation cycle. The leachate was subjected to anaerobic treatment using microbial consortium based product CleanMaxx ANB followed by its counterpart CleanMaxx for aerobic treatment. Post treatment, the physico-chemical properties were analysed and the phytotoxicity was assessed using seed germination assay. The results were interpreted using ANOVA. Findings: The physicochemical parameters of the old and fresh leachate samples were analyzed after biological treatment where the percentage COD reduction was 18.97% and 53.87%; percentage ammoniacal nitrogen reduction was 22.78% and 58.8 %; percentage reduction in TDS was 24.8% and 34.76%; percentage reduction in TSS was 24.05% and 23.5% and percentage colour reduction was 25.01% and 34.35% for old and fresh leachate respectively. The aging of landfill leachate sample may have reduced its biodegradable fraction with the increase in the concentration of high molecular compounds and highly toxic compounds, which may hinder with the microbial degradation process. The seed germination bioassay using Cicer arietinum (Bengal gram) seeds revealed that the percentage germination of seeds exposed to untreated leachate samples (both old and fresh) was 11.1 and 22.2% respectively (p<0.05). Microbial treatment of both these samples improved the germination percentage to 88.8% in both cases. Application/Improvements: The improvement in physicochemical properties and reduction in phytotoxicity indicates that the microbial remediation of landfill leachate could treat the top soils and groundwater tables at contaminated sites, making the surrounding land arable.Keywords: Landfill, Leachate, Microbial Degradation, Phytotoxicity

Enhanced removal of methanethiol and its conversion products in the presence of methane in biofilters

Odors are produced from the treatment and degradation of solid organic waste and seriously affect ecological environments and human health. Control and abatement of volatile sulfur compounds have been identified as critical tasks for maintaining air quality during the treatment and degradation of solid organic waste. Biofiltration is widely used in various applications and is generally known as the least expensive odor treatment technology, but the removal efficiency of organic sulfur compounds is low and variable in biofilters. In this study, the influence mechanism of CH4 on methanethiol removal in biofilters was investigated. Compared with a biofilter containing CH4 and methanethiol (MC biofilter), the removal efficiency of methanethiol in the biofilter only with the input of methanethiol (M biofilter) was lower. The emission rate of methanethiol was 22.8–30.2 mg m−2 d−1 in the M biofilter, which was approximately 2.5 times of that in the MC biofilter. In addition to methanethiol, dimethyl sulfide and dimethyl disulfide were also detected in the biofilters during the experiment. SO42− was the primary product of the conversion of methanethiol in the biofilters. Cloning and Miseq sequencing showed that Thiobacillus and Methylobacter spp. were the predominant methanethiol-degrading bacteria in the biofilters. However, most of the mtoX clones belonged to novel methanethiol-degrading bacteria in the biofilters. These findings illustrate that the presence of CH4 could enhance methanethiol removal in the biofilter, likely because certain methanotrophs such as Methylobacter spp. had methanethiol oxidase and could oxidize methanethiol to formaldehyde, hydrogen peroxide and hydrogen sulfide, the latter of which was further oxidized to SO42−.

Proizvodnja održive energije iz čvrstog otpada putem postupka pirolize - pregled

Environmental pollution is the major problem of the modern society associated with rapid urbanization and industrialization. The thermal technologies such as pyrolysis have been developed for waste reduction and environmental protection. Pyrolysis processes are optimized for fuels (liquid, gases, and char) production by thermal degradation of solid waste, in the absence of air. This study involved a brief review of waste pyrolysis potential. The pyrolysis as a thermal technology is used at commercial scale, predominately in Europe and Japan. The focus of this paper is on the types of pyrolysis technologies which include amounts and products type, reactor design, and economics. Advantages and disadvantages of pyrolysis are also discussed and compared with incineration as a very similar thermal process.

Emission characteristics and health risk assessment of volatile organic compounds produced during municipal solid waste composting

Municipal solid waste degradation during composting generates volatile organic compounds (VOCs), which can pose health risks the staff at the composting site and people living nearby. This problem restricts the widespread application of composting techniques. The characteristics of VOCs emitted from different units at a composting plant and the health risks posed were investigated in this study. A total of 44 VOCs (including alkanes, alkenes, aromatic compounds, halogenated compounds, oxygenated compounds, and sulfur-containing compounds) were identified and quantified. The highest VOC concentration (15484.1 ± 785.3 µg/m3) was found in primary fermentation, followed by the tipping unit (10302.1 ± 1334.8 µg/m3), composting product (4693.6 ± 1024.3 µg/m3), secondary fermentation (929.9 ± 105.2 µg/m3), and plant boundary (370.4 ± 75.8 µg/m3). The mean VOC concentration was 6356.0 µg/m3. The main compounds emitted during primary fermentation were oxygenated and those emitted from the tipping unit were alkenes. Health risk assessments indicate that VOCs did not pose unacceptable non-carcinogenic risks i.e., the HR values were <1 and carcinogenic risks (CR) values were <1.0 × 10−4. These results indicate that VOC emissions do not pose health risks to the staff at the composting site or to people living nearby. However, the cumulative non-carcinogenic and carcinogenic risks posed by the VOC mixture were high, especially for the primary fermentation unit emissions. Therefore, protecting the staff working near the primary fermentation unit should be a priority. Measures should be taken to minimize cumulative non-carcinogenic and carcinogenic risks because people are exposed to a mixture of VOCs mixture rather than to a single type of VOC.

Effect of hydrodynamic mixing conditions on wet oxidation reactions in a stirred vessel reactor

The aim of this study was to investigate the impact of mixing intensity and mixing flow patterns on solid waste degradation, and production of valuable intermediate by-products such as acetic acid. Total suspended solids generally decreased, soluble chemical oxygen demand, dissolved organic carbon, and acetic acid concentration generally increased with the progress of the reaction and increase in the mixing intensity. The results showed that axial-radial flow pattern (using pitch blade impeller) and medium impeller speed (500 rpm) resulted in a higher degree of solid degradation and production of acetic acid.

CFD Modeling of Anaerobic–Aerobic Hybrid Bioreactor Landfills

© 2018 American Society of Civil Engineers. Anaerobic-aerobic hybrid bioreactor landfills, operated in a specific way that combines the benefits afforded by both anaerobic and aerobic processes, can significantly enhance the degradation of municipal solid waste (MSW) and the recovery of energy. The present article describes an application of computational fluid dynamics (CFD) to the numerical simulation of subsurface leachate recirculation and aeration systems in hybrid bioreactor landfills. The objective of the study was to model and investigate the hydrodynamic and biochemical behavior within a hybrid bioreactor landfill. The results indicate that the suitable transition time that ensures that the most methane potential has been exploited and that the hybrid landfill changes to aerobic conditions to shorten the stabilization process effectively is when 70-80% of methane potential has been exploited. A relatively small injection pressure is suggested in the initial stage of aeration forMSWwith small permeability, and the injection pressure can be raised after the pore pressure dissipates and leachate flows out of landfills smoothly. Results also show that a reasonable method of intermittent leachate recirculation during aeration is to start it when the water content decreases to the minimum value required for the hydrolysis reaction and stop it once the maximum hydrolysis rate is reached and that the configuration of the group-well system has an obvious effect on the leachate volume, whereas it appears to have a relatively small effect on the air volume.

Effect of fertilizer prepared from human feces and straw on germination, growth and development of wheat

Solid waste treatment is one of the most important rate-limiting steps in the material circulation and energy flow of Bioregenerative Life Support System (BLSS). In our previous work, an efficient and controllable solid waste bio-convertor has been built and a solid waste degradation efficiency of 41.0% has been reached during a 105-d BLSS experiment. However, the fermented residues should be further utilized to fulfill the closure of the system. One solution might be to use the residues as the fertilizer for plant cultivation. Thus in this study, substrates were prepared using different ratios of the fermented residues to the vermiculite. And the influences of different ratios of the fermented residues on the seed germination, growth, photosynthetic characteristics and antioxidant capacity of wheat were studied. The results showed that the optimal rate of the fermented residue was 5%. With this ratio, the seed germination reached 97.3% with the root length, shoot length and biomass production as 59 mm, 52 mm and 150 mg, respectively, at the 4th day. Besides, the highest straw height of 25.1 cm was obtained at the 21st day. The salinity adversely affected the growth and some relevant metabolic processes of wheat. The Group-40% led to the lowest seed germination of 34.7% and the minimum straw height of 15 cm. This inhibition might be caused by the high Na content of 2118 mg/kg in the fermented residues. Chlorophyll b was more sensitive to the mineral nutrition stress and affects the wheat photosynthetic characteristics. Higher reactive oxygen species levels and reduced antioxidant enzymes may contribute, directly and/or indirectly, to the decline in the observed pigment contents in wheat.

The dynamic of cellulase activity of fungi inhabiting organic municipal solid waste

The study dealt with to identified and screened out potential cellulase producing fungal strains. All the indigenous fungal strains were developed on carboxymethyl cellulose (CMC) mandel media at 30 °C for 3–4 days to examine their congo red cellulase activity. It was found from the primary screening test result that only four isolates Trichoderma viride, Aspergillus niger, Aspergillus fumigatus and Fusarium oxysporum were shown large zone formation that meant they have great potential cellulase activity. Among these, Trichoderma viride and Aspergillus niger strains were showed highest enzymatic activity during the secondary screening, while Trichoderma viride generated the highest protein (89.51 μg/ml). Furthermore, these potential fungal strains will be useful for the organic municipal solid waste degradation.

Preliminary analysis of the bio-mechanical characteristics for High-kitchen Municipal Solid Waste

Degradation of Municipal Solid Wastes (MSW) results in a change in solid skeleton, particle size and pore structure, inducing an alteration of compressibility and liquid/gas conductivity of the wastes. To investigate the complicated biological, hydraulic and mechanical coupled processes of the MSWs, a pilot-scale experimental device which is consist of waste column container, environment regulation system, vertical loading system and measuring system for liquid/gas conductivity is built. With the experimental systems, long-term tests were set up to investigate the biological, hydraulic and mechanical behaviour of the High-kitchen Municipal solid waste with high organic content and high water content. Different values of vertical stress and different degradation conditions (micro-aerobic and anaerobic) were simulated. Throughout the experiments, the changes in total volume, degree of saturation, leachate quantity and chemistry, LFG generation and composition, liquid and gas conductivity were measured. The experimental results will provide solid data for a development of the Bio-Hydro-Mechanical coupled characteristics for High-kitchen Municipal solid waste.

Impact of landfill leachate on the germination of Cucumber (Cucumis sativus)

The generation of landfill leachate occurs due to the degradation of solid waste by the presence of microorganisms. The bioassays allow to understand the relationship between the medium and the leachate, determining the lethal concentration capable of inhibiting 50% of test organisms (LC50), the lowest concentration with observed deleterious effect (LOEC), and the highest concentration without observed deleterious effect (NOEC). This work aimed to determine the impact of landfill leachate on germination and development of radicle and aerial part of cucumber ( Cucumis sativus ) on two substrates. The design was completely randomized and 6 treatments with increasing doses (leachate + deionized water): T1 = 3.125% + 96.875%; T2 = 6.25% + 93.75%; T3 = 12.5% + 87.5%; T4 = 25% + 75%; T5 = 50% + 50% and T6 = 100% leached, and the control (TC) with 100% deionized water, both in triplicates for filter and soil paper substrates. Cucumber tolerance to leachate was identified. It was not possible to determine the LC50 from the treatments, however the 50% and 100% doses inhibited the germination by 83% and 100%, and the NOEC and LOEC values were identified in treatments 12.5%/25% and 25%/50% on filter paper and soil, respectively.

Love plastic: Ashiyana Pipe’s journey to redefine the positioning of plastic

Subject area The case specifically discusses the role of stakeholders and non-market forces and how they can potentially influence the strategic choices of firms. Participants need to have some basic understanding of non-market forces, and stakeholder theory. The case is suitable for courses on sustainable supply chain management, closed loop supply chain management, reverse logistics, green business, environmental management, strategic management and business in emerging economies. Study level/applicability The target audiences for the case are bachelor and first-year MBA students and trainees who are interested in learning the relevance of non-market forces in sustainable growth of an industry and the importance of stakeholder management in the smooth conduct of business. Case overview The case study details how the plastic industry in Kerala faces a non-market threat and how it affects the progress of the industry by using the example of Ashiyana Pipe. Though plastic is a unique material by virtue of its reusability and non-perishable characteristics, it has invited a lot of criticism, as there is a wide spread perception regarding its detrimental impact on the environment (such as choking drains, preventing the degradation of solid waste because of its impermeability, etc.). But the reason for experiencing the detrimental impact of plastic can also be attributed to the inability of the supply chain of the plastic industry to reach a closed-loop status, especially in developing countries such as India, as all categories of post-consumer plastic are not reaching recycling plants. Lack of awareness, lack of community participation in proper segregation and aggregation at the source, absence of incentive systems, weak regulations and poor monitoring are discussed as the common barriers hindering the achievement of closed loop status of plastic supply chain. Detailing the barriers, the case study explains the failure of informal and formal recycling markets in Kerala. Finally, the case study proposes a model with involvement of all the key stakeholders to reposition the hate toward plastic into love through recycling initiatives. Expected learning outcomes Expected learning outcomes of the case are listed below: illustrate the importance of stakeholder involvement in achieving a sustainable business and to stress the importance of a decentralized approach. Illustrate the relevance of non-market forces in sustainable growth of an industry that has significant impact on the surrounding environment and society. Critically analyze the existing business models (based on market mechanism) and suggest possible improvements and alternatives. Understand the challenges that will be faced while implementing an inclusive model with involvement of all stakeholders to reduce the negative impact of non-market forces. Supplementary materials Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes. Subject code CSS 11: Strategy.

Methanethiol generation potential from anaerobic degradation of municipal solid waste in landfills.

Volatile sulfur compounds are the main odorants at landfills. In this study, methanethiol (CH3SH) was chosen as a typical volatile organic sulfur compound, and its generation potential was investigated during the anaerobic degradation of the organic fractions of municipal solid waste (MSW) including rice, flour food, vegetable, fish and pork, paper, cellulose textile, and yard wastes. Among the experimental wastes, gas generation was the highest in the fish and pork waste with a high CH3SH concentration of up to 2.5% (v/v). Sulfur reduction in the solid phase was mostly converted into gaseous sulfur compounds. During the whole experiment, the cumulative CH3SH generation from the fish and pork waste was 0.139Lkgdw-1, which was about 2 and 6 orders of magnitude higher than that from the other experimental wastes. The ratio of CH3SH-S to TS reduction was 31.56% in the fish and pork waste. These results would be helpful to understand the generation of volatile sulfur compounds during the anaerobic degradation of MSW and develop techniques to control odor pollution at landfills.

Vermi-Digestion of Municipal Solid Waste by Red Wigglers to Organic Fertilizer

&lt;p&gt;Ujjain is known as one of the most significant cities of the India as Singhastha 2016 just passed by. Singhastha is an event where Billions of devotees come to take a dip in holy river Shipra for whole One month. In Ujjain average total solid waste generation now is about 226 tons per day in the city area only. A huge amount of money is spent by the Local government on the solid waste management transportation to trenching grounds. The trenching grounds are situated at 20 Kms away from the city in different directions. Solid Waste Management also produces various problems which create many issues with wastage of money therefore; a big need for the ecofriendly disposal technique is been posted. In this paper we are proposing a technique known as vermicomposting which is a good solution to treatment of organic solid wastes. In this technique we have found the degradation of organic municipal solid waste by earthworms. In the research work the temperature is been maintained at 25-35°c, moisture content maintained about at 45- 55% and pH between 7.0-7.3. About 100 grams earthworms {Eisenia Fetida} per kilogram of municipal solid waste were taken. The final result shows that the organic municipal solid wasted are been converted to manure in a time period of 35 - 36 days through vermicomposting technique and about 63% volume of municipal solid waste is reduced for transportation.&lt;/p&gt;

The impact of nanoparticles on aerobic degradation of municipal solid waste

The amount of nanoparticles released from industrial and consumer products has increased rapidly in the last decade. These products may enter landfills directly or indirectly after the end of their useful life. In order to determine the impact of TiO2 and Ag nanoparticles on aerobic landfilling processes, municipal solid waste was loaded to three pilot-scale aerobic landfill bioreactors (80 cm diameter and 350 cm height) and exposed to TiO2 (AT) and Ag (AA) nanoparticles at total concentrations of 100 mg kg-1 of solid waste. Aerobic landfill bioreactors were operated under the conditions about 0.03 L min-1 kg-1 aeration rate for 250 days, during which the leachate, solid waste, and gas characteristics were measured. The results indicate that there was no significant difference in the leachate characteristics, gas constituents, solid quality parameters, and temperature variations, which are the most important indicators of landfill operations, and overall aerobic degradation performance between the reactors containing TiO2 and Ag nanoparticles, and control (AC) reactor. The data also indicate that the pH levels, ionic strength, and the complex formation capacity of nanoparticles with Cl- ions can reduce the toxicity effects of nanoparticles on aerobic degradation processes. The results suggest that TiO2 and Ag nanoparticles at concentrations of 100 mg kg-1 of solid waste do not have significant impacts on aerobic biological processes and waste management systems.