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The treatment of municipal solid waste (MSW) in Peru and some parts of the world is still incipient, mainly due to the lack of technologies implemented to recover this waste; another important cause in Peru is the lack of studies for the treatment of the organic fraction of municipal solid waste (OFMSW). The objectives of this work were: (i) to determine the generation of OFMSW, (ii) to produce quality compost and (iii) to estimate the application rate for the recovery of degraded surfaces. Tools and instruments acquired from the Institute of Sanitary Engineering of FIUBA and the Ministry of the Environment were used to measure physicochemical parameters and environmental estimates. The results showed a per capita MSW generation of 0.472 kg/inhab/day, of which 42.87% was composed of OFMSW or organic fraction of MSW; a feasible availability of organic matter for composting of 6783.79 t/year was determined. The composting experiment was carried out with waste segregated at the MSW treatment plant, installing composting piles with-structurants (WE) consisting of shavings, sawdust and garden waste, and no-structurants (NS). Despite the unfavorable climatic conditions of the region, the maturity and physicochemical properties of the compost were similar to MSW composts recorded elsewhere, with few differences between NS and WE. The main limitation of compost quality was the concentration of heavy metals Cd, Pb and Zn, which were close to or above the limits established in several regulations, which can be significantly reduced by segregating the OFMSW at source. Annual limits and cumulative load limits were used for 10-year applications, the calculated precautionary doses were 25 t/ha/year and 85 t/ha for 10 years in dry weight; correcting for moisture content, the precautionary dose was 40 t/ha/year in wet weight. Depending on the organic fraction of MSW available, compost production and the precautionary dose, 60 to 80 ha/year of degraded agricultural areas and forest plantation nurseries could be recovered with compost; using lower doses it is possible to cover a larger area. From the results, the work provides valuable information to elaborate an integrated MSW management plan, closing the cycle of production, treatment and beneficial use. [ABSTRACT FROM AUTHOR]

In recent years, in response to an increased demand for renewable energy sources, there has been a rise in the rate of energy recovery from municipal solid trash. This study analyses the feasibility of employing a variety of energy recovery methods to produce clean power from municipal solid waste (MSW). The conversion of MSW into a variety of useable sources of energy, such as fuel, heat and electricity, is required for the process of energy recovery. Other strategies for the recuperation of lost energy include gasification, incineration, anaerobic digestion, and the recovery of landfill gas. This article provides a high-level assessment of the advantages and disadvantages associated with each technology that is currently being utilised in India. According to the findings of the study, recovering energy from municipal solid waste is a sustainable and cost-effective option that can fulfil the growing demand for power while simultaneously lowering emissions of greenhouse gases and the amount of rubbish that ends up in landfills. [ABSTRACT FROM AUTHOR]

Landfills are a primary method of waste disposal in developing nations despite their environmental impact. The decomposition of municipal organic waste in landfills generates potent greenhouse gases (GHGs) that contribute to the effects of urban climate change. In Delhi, India, which generates 11,144 tons per day (TPD) of municipal solid waste (MSW), three major landfill sites Ghazipur (GL), Bhalswa (BL), and Okhla (OL) were examined using the well-established in-situ static chamber method to measure emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). This study highlights the need to address these uncertainties by comprehensively capturing GHG emissions from the diverse dynamics within the landfill through rigorous field experiments that account for spatial and temporal variability. The average CH4 emission fluxes from three years of extensive field studies exhibited high variability, measured at 1494 ± 893 (CV = 59.8%), 1576 ± 746 (CV = 47.3%), and 961 ± 322 (CV = 33.5%) mg m−2 h−1 for GL, BL, and OL, respectively. This resulted in CH4 emission factors (EFs) of 5.6 ± 3.5, 4.4 ± 1.9, and 4.2 ± 1.4 g kg−1 for GL, BL, and OL, respectively. The CO2 emission fluxes were 7520 ± 3401 (CV = 45.2%), 8005 ± 3907 (CV = 48.8%), and 5066 ± 1985 (CV = 39.2%) mg m−2 h−1 with corresponding EFs of 20.0 ± 7, 23.3 ± 9, and 16.3 ± 4.7 g kg−1. The N2O emission fluxes were 1210 ± 329 (CV = 27.2%), 998 ± 298 (CV = 30%) and 944 ± 339 (CV = 36%) μg m−2 h−1 with EFs of 3.8 ± 0.1, 2.5 ± 0.2, and 3.1 ± 0.3 mg kg−1 for GL, BL, and OL, respectively. Total GHG emissions from Delhi's landfills were estimated as 328.6 ± 91.9, 231.0 ± 109.5, and 241.1 ± 112.2 Gg CO2 equivalent for 2009–10, 2010–11, and 2011–12. Investigating waste management practices such as spreading, covering, and compaction is essential for understanding their impact on GHG emissions and advancing climate change mitigation through waste-to-energy solutions for sustainable solid waste management and energy production. While the findings offer valuable understandings into emission patterns, the limited sample size introduces some uncertainty, and the EFs should be considered as a preliminary estimation of major GHG in three consecutive years. Future research is necessary to validate these factors with more extensive datasets that capture spatial and seasonal variations in emissions. [ABSTRACT FROM AUTHOR]

In this paper, refuse derived fuels (RDF) produced on an industrial scale in the State of São Paulo (Brazil) were thoroughly characterized. Textiles, paper/cardboard and plastics represent the highest percentage of RDF composition, with the first two fractions being the main contributors to RDF biomass content, which ranges from 39 to 57 wt% on a dry basis (db). Moisture, volatile matter and ash contents range from 19.5 to 35.8, 65.4 to 79.6 and 14.4 to 29.1 wt% db respectively. Carbon content ranges from 43.2 to 53.5 wt% db. The chlorine content is low (0.2–0.8 wt% db) as well as the mercury content which is less than 0.38 μg/kg (db). The net calorific value ranges from 16.9 to 22.0 MJ/kg (db). RDF meet the classification requirements of European and Brazilian standards. Their characteristics demonstrate their potential as a fuel for various thermochemical processes. The use of RDF is therefore an opportunity for a more circular economy. The use of RDF as an alternative fuel in the cement industry brings both economic and environmental benefits. This study provides valuable information for decision-makers to better understand RDF and plan their use in Brazil. [ABSTRACT FROM AUTHOR]

The goal of this paper is to conduct an environmental analysis of a municipal solid waste management system in a midsized region of Southeast Brazil with two million inhabitants. While the current municipal solid waste management system has already eradicated dumps, it landfills practically all its waste, with < 2% open composting and recycling. Therefore, alternatives such as closed composting (CC), anaerobic digestion (AD) with electricity or biomethane production, and incineration are proposed via scenarios in which legal requirements are observed and diversion targets are set. Life cycle assessment (LCA) was performed using EASETECH, a specific software for municipal solid waste (MSW) management systems. The results show that the high diversions scenario (70% recyclables/biowaste) with upgraded biomethane from AD and recycling had 76% greater environmental savings than the similar scenario with the new Brazilian diversion targets (25.8% recyclables, 18.1% biowaste). CC performed much worse than AD, with 80% less savings, although it was marginally better than open composting, with a 95% difference in savings. Despite the benefits of incineration, these scenarios were penalized for their toxicity. Recycling is always recommended if feasible. [ABSTRACT FROM AUTHOR]

The biochemical methane potential (BMP) test is significant for the landfill industry as it provides a means to evaluate the gas potential, and therefore potential degradability, of both incoming and in-place municipal solid waste (MSW). However, the BMP test is not standardized making comparison of BMP results across sites problematic. For example, the BMP test duration has historically ranged from 20 days to several months with most current BMP tests lasting 60 days. However, the gas generation data can potentially be modelled for any of those durations to produce a prediction of the ultimate BMP value (BMPULT). Currently, the predicted BMPULT values of 23 long-duration (115–150 days) BMP tests were used to determine the required quantity of data (i.e. number of days) needed to produce an accurate BMPULT prediction. Results showed that no single test duration produced both accurate and efficient results, so a novel performance-based endpoint was proposed. The relative change in predicted BMPULT values with respect to time (dBMPULT/d t) was chosen as a potential performance-based completion metric. Results indicate that once the absolute normalized dBMPULT/d t value is within <2.5, <1.5 and <0.6% day−1 that the predicted BMPULT is within 20, 10 and 5% of the true BMPULT, respectively. Overall, the use of performance-based metrics for determining BMP test completion will allow for the collection of partial data sets, reduced experimental times and verification of results. [ABSTRACT FROM AUTHOR]

The organic fraction of municipal solid waste (OFMSW) is widely recognized as a possible substrate for anaerobic digestion processes. However, the heterogeneity of this matrix and the presence of slowly biodegradable compounds can slow down anaerobic digestion and reduce its performance. This study compares the effectiveness of different thermal pre-treatments in increasing OFMSW anaerobic digestibility. Thermal pre-treatments were compared with OFMSW shredding, considered as the minimum pre-treatment required in order to reduce particles size of the OFMSW. The pre-treatments were performed in autoclave (121 °C and 1.4 bar for 20 min) or in an ad hoc hydrolysis reactor designed for the experimental trial (140 °C and 7 bar for 30 min) with air or nitrogen as gas phase. The thermal pre-treatments affected methane yield (NmLCH4/gVS), depending on the pre-treatment strategy, with autoclaving allowing for an 80% increase with respect to the control run, and leading to a methane yield of 476 ± 194 NmLCH4/gVS. The pre-treatments in the hydrolysis reactor caused a loss of organic matter (due to its volatilization) reducing the organic loading rate of the digester. Nevertheless, the digester performance in terms of COD (chemical oxygen demand) and VSS (volatile suspended solid) removal showed limited differences among the pre-treatments applied and ranged on average 79–94%. [ABSTRACT FROM AUTHOR]