ABSTRACT: The use of dilute acid (H2SO4, 3%) and alkali (NaOH, 3%) pretreatment methods has some potential how ever to date, these methods effectively increase ethanol production of municipal solid waste (MSW). Enzymatic hydrolysis was carried out with Aspergillus niger, Aspergillus fumigatus and Trichoderma reesei. Finally, the fermentation was done by sugar three ethanologenic yeasts, Saccharomyces cerevisiae, pichia stipitis, canida shehatae for bioethanol production.The highest ethanol yield (22.32%) v/v. was obtained with a pre-hydrolysis treatment consisting of NaOH at 3% concentration, followed by Pichia stipitis and enzymatic hydrolysis with Aspergillus niger. Pre-hydrolysis treatment consisted Enzymatic hydrolysis was carried out with Alkali pretreated wastes yield more sugar as compared to acid treatment using produced more ethanol than others at each time point. The experimental results observed that 80% of the cellulose converted to glucose from the waste which can be easily fermented to production. of ethanol. The ability focus on related environmental issues, such as sustainable waste management, climate change, land use and biodiversity, are discussed.
In the article offered technology hightemperature gasification of the municipal solid wastes with electrothermal stabilization of the process. Technology was adapted for conditions of Ukraine for goal of the experimental verification of the effectivity. Pyrolysis of municipal solid wastes (MSW) and process of the gasification MSW were adapted to the conditions of existing advanced technology of the hightemperature gasification of the carbon containing materials with electrothermal stabilization of the process (HTGTES). Autothermal process parameters of MSW gasification is proved by calculation of the heat and mass balance in conditions of Ukraine.
Marjorie Baynosa, Gladys Anne Bondoc, Leandro Angelo Miguel Sanchez
et al.
The performance of a small-scale two-phase anaerobic digestion system which processes municipal solid wastes, i.e. vegetable and fruit wastes, was evaluated at mesophilic conditions. An anaerobic digester which required 5 L of fresh cow manure, 5 L of solid waste feed, 5 L each of leachate from the solid waste, and 1 L of anaerobic seeding had been constructed. The volume of the feed solids after digestion has significantly reduced after the operation. The total accumulated methane for a solids retention time (SRT) of 20 days contained useful heat energy amounting to 330.27 KJ.
This paper analyzed three dominant approaches of Municipal solid wastes treatments in our country. In this paper we not only compared the advantages and disadvantages of these three dominant approaches but also took analysis to the present situation of MSW(municipal solid wastes) treatment and existing problems in domestic and foreign. At last we thought the future development of MSW treatment: it has many restrictions to take each single way so that comprehensive treatment is the key point to achieve the goal of MSW resource processing.
The management of waste with minimum cost and the environmental burden has recently gained importance in the circular economy. In this study, alternatives for the transportation of wastes by rail and road were compared in terms of cost, environment and personnel requirement benchmarks by using the multi-criteria decision-making software - Right Choice (2.0). The transportation of waste by road is shown with Alternative 1, while the transportation by rail is represented by Alternative 2 (by loading waste-carrying trucks and trailers on the train), Alternative 3 (by loading only trailers on the train) and Alternative 4 (by loading only wastes on the train). As a result, it was determined that the optimum option to transfer the wastes is as specified in Alternative 4, to load only the wastes on the wagons. Importantly, the low operation-maintenance cost of Alternative 4, in other words, its high performance on this benchmark and the high relative importance of the operation-maintenance cost attributed by the stakeholders play a vital role. According to the sensitivity analysis results, Alternative 3 appears as another option close to Alternative 4 while Alternatives 1 and 2, however, remain as options to be evaluated where Alternatives 3 and 4 are not included in decision-making at all. The results of this study show that, depending on the scoring of the criteria in the decision tree, Alternative 4 or 3 could be a better option than the other alternatives, by reducing the number of alternatives and highlighting the good performers.
Surigao del Sur State University has been utilizing the Bioreactor-VermiTechnology through accelerated composting processes in response to theincreasing concern about the amount and management of Municipal Solid Wastes(MSW) and sustainable farming in the municipalities of Tagbina and Barobo,Surigao del Sur, Philippines. The major focus was to evaluate the potential ofBioreactor-Vermi Technology to reduce municipal solid wastes and the potentialof the organic fertilizer produced from these wastes for sustainable farming. Adescriptive research design was utilized in this study employing multiple datacollection techniques which include characterization of compostable solidwastes, their sources, amount of wastes utilized for composting and the amountand quality of organic fertilizer produced. Results revealed that using bioreactor-vermi technology; the biodegradable MSW in the two municipalities is reducedto 6.68% producing 300 tons of organic fertilizers in five years operation utilizedby 200 farmers for the cultivation of various crops within and outside the twomunicipalities. Organic fertilizer produced is in acceptable level for sustainablefarming. As the major composition of waste is organic, waste treatment optionslike bioreactor-vermi composting is effective in reducing municipal solidwastes and producing organic fertilizer for sustainable farming not only in thePhilippines but all over the world.Keywords: Environmental Education, emerging technologies, solid waste utilization,descriptive-evaluative design, Philippines
Settlement evaluation in sanitary landfills is a complex process, due to the waste heterogeneity, time-varying properties and influencing factors and mechanisms, such as mechanical compression due to the load application and creep, and physical-chemical and biological processes caused by the wastes decomposition. Many empirical models of analysis and long-term settlement prediction are reported in the literature, which require the application to real case studies in order to be validated. In this paper, four models of long-term settlement prediction (Rheological, Hyperbolic, Composite and Meruelo models) reported in the literature were applied to assess the mechanical behavior of an experimental landfill, composed of 6 different cells of municipal solid waste. Concerning the long-term settlement prediction, the results enabled a critical evaluation of the models, pointing out some advantages and limitations. During the monitoring period of 3 years, significant vertical strains were observed (of up to 22%) in relation to the initial height of the experimental landfill, which can be considered high and is due to fresh wastes with high organic content disposed. The results also suggest that the operational procedures influenced the settlements in the experimental landfill. The long-term settlement prediction indicated a final strain range from 22% to 42%, with respect to initial waste height and the composite model presented better comparisons between field measurements and predictions.
The aim of this research was to study the anaerobic conversion efficiency of the organic fraction of municipal solid waste (OFMSW). In order to compare and appraise our techniques and respective conversion efficiencies, primary sewage sludge (PSS) assays were also performed. OFMSW has a high cellulose content (32.9% TS) followed by lignin (12.5% TS), protein (9.61% TS), lipids (5.94% TS) and hemicellulose (5.2% TS). PSS is equally rich in lipids (19.8% TS), protein (18.2% TS) and lignin (19.6% TS), followed by cellulose (13.4% TS) and hemicellulose (5.5% TS). Assays were run in CSTRbiodigesters operated at 35°C and 20 days hydraulic retention time (HRT). Three organic loading rates - 1.0, 2.7 and 3.8 OFMSW g VS/Lr.d (gram of volatile solids per liter of reactor per day) - were studied. PSS was assayed only at 1.0 g VS/Lr.d. Concerning the conversion efficiencies, the most important component for the OFMSW anaerobic digestion is cellulose (74.0 - 77.8% conversion), while lipids (70.0 - 80.6% conversion) are the most important for PSS. The biodegradability of the other organic components are also presented and discussed. Some literature data about OFMSW anaerobic digestion processes are discussed in view of the results presented here. The similarities between our results and those of the so-called dry fermentation processes are also discussed in order to evaluate efficiencies of biogas and CH4 production versus volatile solids removal.
With the advent of strict air-pollution laws, incinerators used for municipal refuse must be equipped with air-pollutioncontrol systems to reduce harmful gaseous and particulate emissions. Wet scrubbing systems are often employed since they are capable of efficiently removing both types of pollutants.