Organic Municipal Solid Waste Research Articles

Briefing: Towards a sustainable energy: the potential of biomass for electricity generation in Oman

Oman, like other Arabian Gulf countries, depends on oil and gas to produce electricity. However, these resources are not guaranteed to last forever and constitute one of the energy security issues in the country. This paper explores the potential of using biomass energy resources for electricity generation in Oman. Energy from biomass resources is counted as a type of renewable energy, which means that its availability is not affected by the lack of sources and the increasing price of fossil oil. The review of biomass energy shows that waste from different sources such as wood and woody plants and their wastes, agricultural crops and residues, municipal solid organic wastes, animal wastes, sewage, waste from organic industrial processing and food processing, and aquatic plants and algae can be used for electricity generation. Biomass from animal manure and waste water are reported as having potential for electricity generation. The results show that a total of 2651·81 GWh/year electricity can be produced from animal manure and waste water, which corresponds to 10% of the total electricity consumption in Oman. Although there is potential to use biomass for sustainable electricity generation, several environmental, social and technological factors associated with biomass energy need to be considered before adopting such resources.

Vine performance and wine composition of ‘Chardonnay’ in relation to organic soil amendment in Mediterranean environment

Preservation and improvement of soil organic matter content in vineyards are key goals of agroecosystem resilience against climate change and its negative effects on grapevine water status and vine physiology. There is still a lack of information on the effects of organic amendments on grapevine functions and yield performance. The following research was carried out during the 2016 season in a commercial 'Chardonnay' vineyard located in Apulia region according to a randomized block design, where one factor of fertilization (commercial composted municipal solid organic wastes) was tested. Treatments were: no fertilized control vines (NFC), moderate fertilized vines (D1) at rate of 1 kg vine-1 of organic amendment (4.3 t ha(-1), at the rate of 86 kg N ha(-1)), high fertilized vines (D2) at rate of 1.5 kg vine-1 (6.6 t ha(-1), 132 kg N ha(-1)). The leaf gas exchange during growing season did not show significant differences in terms of net CO(2) assimilation, stomatal conductance, transpiration and water use efficiency. However, lower leaf temperature on D1 and D2 vines was measured. Vines fertilized with organic amendment showed a better water status during the warmest summer days since organic compounds improve the soil-water holding capacity. Monthly field measurements of the greenness of the leaves (SPAD index) revealed the highest green color intensity of leaves by D2 treatments (+11%) to be related to the highest nitrogen amount. Compared to unfertilized vines, D2 vines (high amendment dose) determined a significant increase in yield per vine (+21%) in relation to the highest cluster weight. At harvest, grapes had the same chemical composition with no differences in term of sugar content and pH, while an increment of titratable acidity on D1 and D2 vines was noted. Wines of different treatments have shown similar chemical parameters (alcohol content, titratable acidity and pH). Our preliminary results indicated that application of a high level of soil organic amendment on 'Chardonnay' vines increased grapevines yield while improving soil properties (soil organic content and water retention), contrasting summer drought effect on vines in a Mediterranean environment.

The role of management instruments in the diversion of organic municipal solid waste and phosphorus recycling

Organic waste, which contains essential plant nutrients such as phosphorus, constitutes 30%–50% of municipal solid waste in developed countries. Unfortunately, much of this resource is buried in landfills or incinerated. Many jurisdictions have, therefore, adopted the diversion of organic waste and the recycling of nutrients as policy goals. We used data sets from Europe and Ontario, Canada, to explore the impact of socio-economic and management factors on the rates of organic waste diversion and examined the effect of this diversion on phosphorus recycling. Organic diversion rates were highly correlated with income in Europe and with infrastructure, such as source-separated organic waste collection, in Ontario. Significant correlations were also observed between diversion rates and the use of policy instruments such as economic incentives, legislative organic waste bans, and curbside bag limits. We estimated that 39%–63% of the phosphorus in diverted organics is returned to arable land. Ultimately, we found that although socio-economic factors influence the success of organic waste diversion, policies, accessible infrastructure, economic incentives, and legislative requirements can be leveraged to improve the recycling rate of organic waste and the nutrients they contain.

Acidogenic valorization of vegetable waste for short chain carboxylic acids and biohydrogen production: Influence of pretreatment and pH

The present study aimed to valorize the vegetable waste fraction of organic municipal solid waste (VW) for the production of biobased products viz., reducing sugars (RS), short chain carboxylic acids (SCA)/volatile fatty acids (VFA) and biohydrogen (H2). Firstly, VW was subjected to pretreatment using physical (PS), chemical (CHE) and physicochemical (PSC) methods for RS production. Among the studied pretreatment methods, PSC resulted in higher RS solubilization with acid catalyzed conditions (1% H2SO4/HCl: 42.4/40.8 g/l). Subsequently, resulting organic-rich PSC hydrolysate (RS) was acidogenically fermented for the production of SCA and biohydrogen at varying initial pH conditions (4, 6 7 and 10). Acidogenic fermentation at pH-6 resulted in higher SCA (0.62 g SCA/g RS) and biohydrogen production (1.22 l) followed by pH-10 (0.53 g SCA/g; RS, 0.94 l), pH-7 (0.37 g SCA/g; RS, 0.58 l) and pH-4 (0.32 g SCA/g; RS, 0.27 l). SCA composition at pH 6, 7 and 10 was majorly composed of acetic acid, while butyric acid was found to be dominant at pH 4. SCA's are known to be platform chemicals and hydrogen is a green fuel, production of which using VW accounts the sustainability to current solid waste management practices with the scalable co-product synthesis.

The Study of Anaerobic Co-Digestion of Non-Uniform Multiple Feed Stock Availability and Composition in Nigeria

This paper reports the research work carried out on the study of anaerobic co-digestion of non-uniform multiple feed stock availability and composition in Nigeria. Organic municipal solid wastes comprises of the composition of corn cobs, potato peels, pineapple peels, rice waste, yam peels, cassava peels, orange peels, garri leftover and banana peels, was digested separately and the same time co-digested with wastewater collected from septic tanks, abattoir, and cold room in Benin City, Nigeria. The results obtained shows that the co-digestion of organic municipal solid wastes and wastewater had better average biogas yields (0.625), shorter retention period of 29 days, frequent number of evacuation and average rate of biogas yield of 0.0217 when compared to anaerobic digestion of organic municipal solid wastes only with an average biogas yield of 0.4025, longer retention period of 38 days and average rate of biogas yield of 0.0106. Therefore, anaerobic co-digestion of organic municipal solid wastes and wastewater enhances better biogas yields.

Cultivation of Potted Sea Fennel, an Emerging Mediterranean Halophyte, Using a Renewable Seaweed-Based Material as a Peat Substitute

Sea fennel (Crithmum maritimum L.), an emerging halophyte species, represents a nutritious and refined food product. In this study, the effect on yield and quality of potted sea fennel grown on three posidonia (Podisonia oceanica (L.) Delile)-based composts (a municipal organic solid waste compost, a sewage sludge compost and a green compost) and a peat-based substrate was analyzed. Composts were used both pure and mixed with peat at a dose of 50% on a volume basis. We hypothesized that the halophytic nature of this plant might overcome the limitations of high-salinity compost-based growing media. The growth parameters, color traits and trace metals content (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) of the edible parts were compared. Independently of the substrates, the average total and edible yields were 51 and 30 g plant−1, respectively, while the average waste portion was about 41%. The use of posidonia-based compost did not affect the color traits of sea fennel plants as compared with samples grown on the commercial peat-based substrate. In general, potted sea fennel grown on both posidonia-based composts and commercial peat-based substrate appeared a good source of essential micronutrients. Only a weak reduction of Fe and Mn concentrations was observed in plants grown on posidonia-based composts, especially when used at the highest dose. Independently of the growing medium, the content of potentially hazardous trace elements (Cd and Pb) in the edible parts of sea fennel was always below the maximum admissible limits fixed by the European legislation. Results indicate that posidonia-based composts can be used as a sustainable peat substitute for the formulation of soilless mixtures to grow potted sea fennel plants, even up to a complete peat replacement.

Production and partial characterization of dehairing alkaline protease from Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 by using organic municipal solid wastes

Alkaline proteases have applications in numerous industries. In this study, we have isolated and screened proteolytic bacteria from poultry wastes mixed soil and identified two bacterial isolates as Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 based on 16S rDNA sequencing. Maximum level of protease production was achieved after 24 h of fermentation in a basal medium. The optimal temperature, initial pH of the media and agitation for alkaline protease production by these two isolates were 30 °C, pH 9.0 and 120 rpm, respectively. The both bacterial isolates produced maximum level of protease with 3.0% organic municipal solid wastes (OMSW) as the sole source of carbon and nitrogen under previously optimized fermentation conditions. In comparison with the shake flask, protease production increased about 2.5-fold in the bioreactor with reduction in fermentation period. The partial purification of protease resulted in a final 45.67 and 34.86-fold purified protease with a specific activity of 8335.34 and 9918.91 U/mg protein and a typical yield of 9.75 and 9.41% from B. subtilis and E. indicum, respectively. The optimum temperature and pH of the partially purified protease from the both sources was 40 °C and pH 9.0, respectively. Protease from the both isolates was stable at pH 7.0–12.0 and at temperatures up to 50 °C. The effects of protease inhibitors indicated that the protease from B. subtilis might be serine and cysteine type and from E. indicum might be cysteine type. Mg2+, K+ and Ca2+ stimulated but Zn2+, Hg2+, Co2+ and Fe3+ strongly inhibited the protease activity. The partially purified protease from B. subtilis substantially dehaired cow skin and decomposed gelatinous compound from X-ray film. Our study revealed that OMSW can be used as raw material for production of bacterial extracellular protease and alkaline protease from B. subtilis might be potential for industrial and biotechnological applications.

Study on potency of municipal solid waste conversion into renewable energy by thermal incineration and bioconversion: case study of Medan city

Municipal solid waste (MSW) in Medan City is facing problems either with the quantity and management of MSW. Local authority only dumped approximately 73.9% MSW in the landfill over the years. Spontaneous phenomena of methane formation in dumping site indicates the potency of MSW conversion into energy by biochemical conversion. On the contrary, the presence of plastics, woods, papers, etc. in the MSW show the potency of MSW to be treated by thermal conversion. Both thermal incineration and anaerobic digestion may convert MSW Medan City into energy. This study evaluates potency of MSW conversion into renewable energy using proximate and ultimate analysis. Overall, MSW of Medan City has the opportunities to be converted into energy by both thermal and biochemical conversion with a special requirement such as pre-dry the MSW prior incineration process and degrade organic MSW in a bioreactor.

Utilization of Municipal Organic Solid Waste for Production of Activated Carbon in Saudi Arabia

In this research, mesoporous activated carbon (AC) was produced from municipal organic solid waste, where chemical activation with $$\hbox {H}_{3}\hbox {PO}_{4 }$$ as the activating agent was employed. Effects of various parameters, such as activation temperature, concentrations of $$\hbox {H}_{3}\hbox {PO}_{4 }$$ , and activation time, on the characteristics of the produced AC were investigated. Moreover, adsorption performance of the produced AC under different conditions of activation was evaluated using methylene blue and heavy metals as the adsorbates. The produced AC was characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller (BET). The results revealed that characteristics of the produced AC were highly influenced by activation temperature and concentration of $$\hbox {H}_{3}\hbox {PO}_{4 }$$ , whereas activation time has insignificant effect. At optimum activation conditions of activation temperature ( $$700^{\circ }\hbox {C}$$ ), activation duration (2 h) and $$\hbox {H}_{3}\hbox {PO}_{4 }$$ concentration (30%), the results showed that BET surface area, AC yield and MB removal efficiency were 792.93 $$\hbox {m}^{2}/\hbox {g}$$ , 32 and 100%, respectively. Moreover, removal efficiencies of $$\hbox {Cd}^{2+}$$ and $$\hbox {Pb}^{2+}$$ were 55 and 64%, respectively.

Effect of Liquid Digestate on Agricultural Soil-II: Microbial Population Dynamics

The aim of this study was to investigate the effect of liquid digestate (produced from anaerobic digestion of organic municipal solid waste) on the population dynamics of selected soil microbial groups during cultivation of maize plants. Maize seeds where subjected to various concentrations (between 0% to 72%) of the digestate with a total of ten (10) runs. One set of experimental runs were treated with one-time application of the corresponding digestate concentration (OTDA). Another set of experimental runs were treated with two-time application of the corresponding digestate concentration (TTDA). The first application of the digestate (for OTDA and TTDA) was conducted two weeks after sowing while the second application (for TTDA alone) was conducted three weeks after the first application. During the growth of maize plants, the populations of soil aerobic bacteria (AEB), strict anaerobic bacteria (SAB), ammonia oxidizing bacteria (AOB), nitrate reducing bacteria (NRB) and fungi (FUN) where monitored using standard cultural methods. In OTDA and TTDA treatments, the population of soil AEB, SAB, AOB, NRB and FUN ranged from 3.0 × 106 CFU/g to 50.2 × 106 CFU/g and 3.1 × 106 CFU/g to 78.6 × 106 CFU/g; 1.9 × 104 CFU/g to 7.2 × 105 CFU/g and 2.2 × 104 CFU/g to 2.53 × 105 CFU/g; 0MPN/g to 4.3 × 104 MPN/g and 0MPN/g to 3.9 × 105 MPN/g; 0 MPN/g to 4.4 × 105 MPN/g and 0 MPN/g to 1.4 × 105 MPN/g and 1.3 × 103 CFU/g to 2.6 × 104 CFU/g and 1.2 ×103 CFU/g to 9.4 × 103 CFU/g respectively before and 70 days after applying the digestate. Bacteria species isolated appear to belong to genera such as Arthrobacter, Azotobacter, Flavobacterium, Nocardia, Bacillus, Clostridium, Cellulomonas, Micrococcus and Pseudomonas. Fungi species isolated appear to belong to genera such as Aspergillus, Cladosporium, Fusarium, Geotrichum, Penicillium, Rhizopus and Trichoderma. Digestate application appears to have increased the population of soil microbes with time during the cultivation of maize plants.

Characteristic of Bioorganic Component of Municipal Solid Waste

Purpose. Characteristics of the easily decomposed organic municipal solid waste flow: evaluation of composition, main components content and determination of possible recycling directions. Methods. System analysis methods, statistical processing of data were used. Results. Almost 60% of the municipal solid waste mass was composed of components containing biodegradable carbon – food and garden wastes, paper and cardboard, textiles, nappies, rubber and leather, wood. The total content and correlation between the main components depend on local conditions and change over time. The coefficient of variation was chosen as a criterion for assessing the variability of the content of individual components in the MSW total mass. It was shown that the most variable was the content of rubber and leather, as well as wood; the most stable characteristic was the content of food waste. The municipal solid waste management practice is to dispose of easily decomposed organic waste into landfill and dumps, which are sources of environmental pollution by e.g. greenhouse gases. The exception is some part of paper and cardboard. Given the obtained characteristics of wastes containing biodegradable carbon, we present the main directions of its recycling that are possible today. Conclusions. A group of wastes containing biodegradable carbon constitutes a significant proportion of MSW. The correlation between the different components of this group is a characteristic feature of the generation source and should be taken into account by developing an effective system of waste management for a particular city or region. The current waste management practice leads to waste disposal into landfill and dumps, which are sources of environmental pollution. On the other hand, such waste can be efficiently recovered, especially the largest by weight food, garden waste and paper and cardboard. However, a necessary condition for this purpose is their separation from the general municipal solid waste stream in the moment of waste generation.

Effect of Seasonal Variation on Anaerobic Treatment of Organic Municipal Solid Waste-II: Population Dynamics of Bacteria and Archaea Communities

This study was designed to investigate the effect of seasonal variation on population dynamics of bacteria and archaea communities during anaerobic treatment of organic municipal solid waste. The waste was subjected to anaerobic treatment inside one-stage 250 L-capacity batch-type mesophilic poly-tank reactors with used volume of 230 L, substrate concentration of 5.53% total solids, rumen juice as the source of microbial inoculum and a retention time of 84 days. The first Anaerobic Digestion (ADH) treatment was conducted during the dry season (between February and April, 2016) while the second Anaerobic Digestion (ADC) treatment, a repeat of the first process, was conducted during the rainy season (between July and October, 2016). To monitor performance of the anaerobic treatment process, populations of selected bacteria and archaea groups and biodegradation of the feed where estimated with time using standard methods. Inside the ADH system, the population of Acetoclastic Methanogens (AMA), Hydrogenotrophic Methanogens (HMA), Strict Anaerobic Bacteria (SAB) and Facultative Anaerobic Bacteria (FAB) ranged from not-detected to 8.76 × 106 CFU/ml, not-detected to 7.93 × 106 CFU/ml, 1.45 × 106 CFU/ml to 4.18 × 107 CFU/ml and 1.2 × 106 MPN/ml to 7.5 × 107 MPN/ml respectively with time. Inside the ADC system, the population of AMA, HMA, SAB and FAB ranged from not-detected to 1.46 × 106 CFU/ml, not-detected to 1.05 × 106 CFU/ml, 9.2 × 105 CFU/ml to 1.85 × 107 CFU/ml and 2.4 × 106 MPN/ml to 1.2 × 108 MPN/ml respectively with time. Biodegradation of the feed inside the ADH system and the ADC system, increased to 97.21% and 75.86% respectively after 84 days. Microbial populations inside the ADH-system increased significantly more than the microbial populations inside the ADC-systems with time, leading to a significantly (p<0.05) better performance of the ADH-system than the ADC-system with respect to biodegradation of the feed. Therefore, seasonal variation appears to have influenced the population dynamics of microbial communities during anaerobic degradation of the waste.

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.

Post-treatment of biogas digestate – An evaluation of ammonium recovery, energy use and sanitation

The utilization of digestate from anaerobic digestion (AD) processes offers the possibility to recycle nutrient from organic waste materials back to the food chain. However, digestates are characterized by a high water content resulting in high storage capacities and transportation costs. Various organic wastes such as organic municipal solid waste (oMSW) require sanitation with at least one hour hydraulic retention time (HRT) at 70°C to inactivate pathogens for the safe release of the material. Consequently, the sanitation process is one of the largest energy consumers in the whole AD process chain. In this study, a post-treatment of the biogas digestate was evaluated regarding the potential for energy savings and nutrient recovery via nitrogen stripping in comparison to the conventional pre-sanitation of the organic waste. With increasing HRT (one to three hours) and aeration flow (0.0-5.3 L air per L digestate and minute) more condensate and ammonia was removed from the digestate. The total ammonia removal from the digestate after one and three hours with the highest aeration flow rate reached 42% and 80%, respectively. However, energy requirement for aeration exceeded energy savings from the lower volume for sanitation after the digestion substantially. On a system level, a positive energy balance could still be achieved by taking energy savings from the replacement of mineral fertilizer (36 GJ per ton NH4) into account. Moreover, the digestate as fertilizer could be applied in a more demand-oriented way by adding ammonium sulphate obtained by the ammonia stripping during the post-treatment.

Preliminary evaluation of pathogenic bacteria loading on organic Municipal Solid Waste compost and vermicompost

The use of composts or vermicomposts derived from organic fraction of Municipal Solid Waste (OFMSW) brought about certain disagreement in terms of high level of bacterial pathogens, thereby surpassing the legal restrictions. This preliminary study was undertaken to compare the evolution of pathogenic bacteria on OFMSW compost against vermicompost (generated by Eudrilus eugeniae) with promises of achieving sanitation goals. Analysis to quality data showed that OFMSW vermicomposting caused a moderately higher reduction in total coliforms in contrast to composting. E. coli in OFMSW composts was found to be in the range of 4.72–4.96 log10 CFU g−1 whilst on a clear contrary, E. coli was undetectable in the final vermicomposts (6.01–6.14 logs of reduction) which might be explained by the involvement of the digestive processes in worms' guts. Both OFMSW composts and vermicomposts generated Salmonella-free products which were acceptable for agricultural usage and soil improvement. In comparison to compost, the analysis of this research indicated that earthworm activity can effectively destroy bacterial pathogenic load in OFMSW vermicomposts. But still, this study necessitates extra research in order to comprehend the factors that direct pathogenic bacteria in vermicomposting and earthworm-free decomposition systems.

Partial purification and characterization of serine protease produced through fermentation of organic municipal solid wastes by Serratia marcescens A3 and Pseudomonas putida A2.

Proteolytic bacteria isolated from municipal solid wastes (MSW) were identified as Serratia marcescens A3 and Pseudomonas putida A2 based on 16S rDNA sequencing. Protease produced through fermentation of organic MSW by these bacteria under some optimized physicochemical parameters was partially purified and characterized. The estimated molecular mass of the partially purified protease from S. marcescens and P. putida was approximately 25 and 38 kDa, respectively. Protease from both sources showed low Km 0.3 and 0.5 mg ml−1 and high Vmax 333 and 500 µmole min−1 at 40 °C, and thermodynamics analysis suggested formation of ordered enzyme-substrate (E-S) complexes. The activation energy (Ea) and temperature quotient (Q10) of protease from S. marcescens and P. putida were 16.2 and 19.9 kJ/mol, and 1.4 and 1.3 at temperature range from 20 to 40 °C, respectively. Protease of the both bacterial isolates was serine and cysteine type. The protease retained approximately 97% of activity in the presence of sodium dodecyl sulphate. It was observed that the purified protease of S. marcescens could remove blood stains from white cotton cloth and degrade chicken flesh remarkably. Our study revealed that organic MSW can be used as raw materials for bacterial protease production and the protease produced by S. marcescens A3 might be potential for applications.

Environmental assessment of waste feedstock mono-dimensional and bio-refinery systems: Combining manure co-digestion and municipal waste anaerobic digestion

Organic municipal solid waste (OMSW) as a feedstock for energy recovery and material recycling offers the potential to reduce environmental impacts from energy production while displacing emission-intensive waste management strategies such as landfills. This paper quantifies the environmental impact of anaerobic digestion of local, residual biomass. A life-cycle assessment was jointly performed for two scenarios for the biological treatment of local organic municipal solid waste and pig manure in the Netherlands. Scenario 1 was a separate treatment using anaerobic digestion, and Scenario 2 was a bio-refinery system that integrates anaerobic digestion of organic, municipal solid waste, and co-digestion of pig manure and other organic co-substrates∖. For both scenarios, electricity and heat are generated using a combined heat and power engine. The bio-refinery system (Scenario 2) contribution to climate change resulted in 0.16 Mt CO2 eq./yr, which is lower than the 0.17 Mt CO2 eq./yr of Scenario 1. Both scenarios are found to be beneficial with regard to resource depletion and human toxicity. The integration of organic waste and manure anaerobic digestion has no effect on acidification and terrestrial eutrophication impact categories, resulting in 43.59 AE eq. and 86.33 AE eq. for Scenario 1 and 43.58 AE eq. and 86.30 AE eq. for Scenario 2. Moreover, Scenario 2 yields 18% lower emissions than those from natural gas derived electricity in the Netherlands. The biorefinery system represents an opportunity to improve organic waste-management strategies, at the same time as reducing the environmental impact from energy production and the costs for surplus manure disposal by producing high-quality commodities that can be traded on the market.

Short-term greenhouse emission lowering effect of biochars from solid organic municipal wastes

Qatar economy has been growing rapidly during the last two decades during which waste generation and greenhouse gas emissions increased exponentially making them among the main environmental challenges facing the country. Production of biochar from municipal solid organic wastes (SOWs) for soil application may offer a sustainable waste management strategy while improving crop productivity and sequestering carbon. This study was conducted to (1) investigate the physicochemical parameters of biochars for SOW, (2) select the best-performing biochars for soil fertility, and (3) evaluate the potential benefits of these biochars in lowering greenhouse gases (GHGs) during soil incubation. Biochars were produced from SOW at pyrolysis temperatures of 300–750 °C and residence times of 2–6 h. Biochars were characterized before use in soil incubation to select the best-performing treatment and evaluation of potential GHG-lowering effect using CO2 emission as proxy. Here, soil–biochar mixtures (0–2%w/w) were incubated in greenhouse settings for 120 days at 10% soil moisture. Soil properties, such as pH, EC, TC, and WHC, were significantly improved after soil amendment with biochar. Two biochars produced from mixed materials at 300–500 °C for 2 h and used at 0.5–1% application rate performed the best in enhancing soil fertility parameters. A significant decrease in CO2 emission was observed in vials with soil–biochar mixtures, especially for biochars produced at 500 °C compared the corresponding raw materials which exhibited an exponential increase in the CO2 emission. Hence, application of biochar to agricultural soils could be beneficial for simultaneously improving soil fertility/crop productivity while sequestering carbon, thereby reducing anthropogenic emissions of GHGs.

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;

Bio-charcoal production from municipal organic solid wastes

The economic and environmental problems of handling the increasingly huge amounts of urban and/or suburban organic municipal solid wastes MSW, from collection to end disposal, in addition to the big fluctuations in power supply and other energy form costs for the various civilian needs, is studied for Baghdad city, the ancient and glamorous capital of Iraq, and a simple control device is suggested, built and tested by carbonizing these dried organic wastes in simple environment friendly bio-reactor in order to produce low pollution potential, economical and local charcoal capsules that might be useful for heating, cooking and other municipal uses. That is in addition to the solve of solid wastes management problem which involves huge human and financial resources and causes many lethal health and environmental problems. Leftovers of different social level residential campuses were collected, classified for organic materials then dried in order to be supplied into the bio-reactor, in which it is burnt and then mixed with small amounts of sugar sucrose that is extracted from Iraqi planted sugar cane, to produce well shaped charcoal capsules. The burning process is smoke free as the closed burner’s exhaust pipe is buried 1m underground hole, in order to use the subsurface soil as natural gas filter. This process has proved an excellent performance of handling about 120kg/day of classified MSW, producing about 80-100 kg of charcoal capsules, by the use of 200 l reactor volume.