Municipal Solid Waste Processing Research Articles

Environmental and Technological Aspects of the Functioning of Municipal Solid Waste Recycling Complexes (on the Example of the Moscow Region)

The existing scheme, key operations and technologies used in the company for sorting and processing municipal solid waste in the Moscow region have been considered. The features of waste streams entering the waste processing system have been studied, quantitative and qualitative characteristics of the morphological composition have been presented, actual data on the composition of pollutant emissions generated at different stages of waste sorting and processing have been analyzed, the most problematic areas and priority eco-toxicants have been identified.

Influence of main operating parameters on the incineration characteristics of municipal solid waste (MSW)

To study the influence of the main operating parameters on the incineration characteristics of municipal solid waste (MSW), a 375 t/d mechanical grate incinerator is selected as the research object, and the effects of primary air temperature, secondary air arrangement, and grate speed on the MSW incineration process are simulated, and experimental tests are carried out under different primary air temperature and grate speed conditions. The results show that the relative errors between the measured and simulated values of the incinerator outlet O2 content and the measurement point temperature are within ±5% for all test conditions. When the primary air temperature increases from 423 K to 503 K, the position where the MSW incineration ends moves 3.32 m towards the front of the grate, and the moisture evaporation and fixed carbon combustion rates also increase, but the maximum volatile release rate and the optimal incineration condition of the MSW occur at the primary air temperature of 483 K. The increase in grate speed delays the incineration process of MSW and decreases the moisture evaporation rate and fixed carbon combustion rate, but it worsens the incineration effect of MSW. When the grate speed increases from 6.94 m/h to 13.88 m/h, the MSW incineration process is delayed by 3.20 m, and the moisture evaporation and fixed carbon combustion rates decrease by 43 kg·m−2·h−1 and 9 kg·m−2·h−1, respectively. To achieve the optimal operating conditions, the secondary air volume ratio of the front and rear arches is 1.59:1, the secondary air direction of the front arch is 40° and 60°, and that of the rear arch is 0° for the primary air temperature of 463 K and 483 K, respectively. This study can provide useful insights for optimizing the design and operation of mechanical grate incinerators.

Improving the Environmental Efficiency of a Mobile Power Plant with a Low-Emission Gas Generator

A mobile power unit is proposed to prepare for the processing of municipal solid waste using an environmentally friendly boiler unit developed by "Baltkotlomach" LLC. The design, principle and results of operation of an integrated combustion product purification system are presented. The conclusion was made that the developed power system meets environmental requirements and allows for efficient disposal of municipal solid waste.

New multi-source waste co-incineration and clustering park operating model for small- and medium-sized city: A case study in China

With improvements in urban waste management to promote sustainable development, an increasing number of waste types need to be sorted and treated separately. Due to the relatively low amount of waste generated in small- and medium-sized cities, separate treatment facilities for each waste type lack scale, waste is treated at a high cost and low efficiency. Therefore, industrial symbiosis principles are suggested to be used to guide collaborative waste treatment system of multi-source solid wastes, and co-incineration is the most commonly used technology. Most existing studies have focused on co-incineration of one certain waste type (such as sludge or medical waste) with municipal solid waste (MSW), but the systematic design and the comprehensive benefits on a whole city and park level have not been widely studied. Taking the actual operation of a multi-source waste co-incineration park in south-central China as an example, this study conducted a detailed analysis of the waste-energy-water metabolism process of MSW, sludge, food waste, and medical waste co-incineration. The environmental and economic benefits were evaluated and compared with the single decentralized waste treatment mode. The results showed that the multi-source waste co-incineration and clustering park operating model was comprehensively superior to the single treatment mode, greenhouse gases and human toxicity indicators were decreased by 11.87% and 295.74%, respectively, and the internal rate of return of the project was increased by 29.35%. This mainly benefits from the synergy of technical system and the economies of scale. Finally, this research proposed policy suggestions from systematic planning and design, technical route selection, and an innovative management mode in view of the potential challenges.

A Master’s Course Can Emphasize Circular Economy in Municipal Solid Waste Management: Evidence from the University of Pisa

Municipal solid waste (MSW) represents a significant global threat, which has to be managed by a model of production and consumption involving the sharing, leasing, reusing, repairing, refurbishing, and recycling of existing materials and products for as long as possible, otherwise known as a circular economy (CE). However, there is not a universal rule for waste recycling strategies, and it has been demonstrated that active public participation is crucial in the satisfactory management of waste. In this context, citizen participation and education are two interrelated approaches, which can help to engage and inform people regarding waste and its wider impact. The present study describes the development of an interdisciplinary hackathon (hackathons are events whereby individuals from different backgrounds are brought together to work on the solutions to different problems), targeted to students of a postgraduate Master’s course on Sustainable Development and Climate Change in order to develop and understand the MSW problems and priorities currently being targeted, with the aim to propose new potential solutions for MSW reduction, reuse, and recycling. Following an empirical approach, four working groups were established and assigned the following specific tasks: (i) communication/citizen education on MSW; (ii) the reduction of MSW production; (iii) innovative solutions to recover and enhance secondary raw materials deriving from MSW processing; and (iv) the eco-design of the cities of the future concerning CE principles applied to MSW recycling. Overall, the following main findings were derived from the hackathon event: (i) an essential objective of the CE strategy is to drive Europe’s internal market towards the production and consumption of more sustainable products, thus reducing environmental and social pressures, while still retaining value; (ii) the most effective ways of tackling environmental problems are to ‘change the way we consume’, as well as to ‘change the way we produce and trade’, with the responsibility shared between businesses, governments, and the EU, as well as the citizens themselves. In this scenario, research and innovation play a key role in driving the necessary systemic changes to reach climate neutrality and ensure an inclusive ecological and economic transition. Overall, the present study confirms how the hackathon represents an effective tool to engage citizens in participation and education.

Smart-sight: Video-based waste characterization for RDF-3 production

A material recovery facility (MRF) can transform municipal solid waste (MSW) into a valued commodity called refuse-derived fuel (RDF) as a promising solution to waste-to-energy conversion. The quality of the produced RDF significantly relies on the composition of in-feed waste and waste characterization method applied for auditing purposes, a process that is both time-consuming and fraught with potential hazards. This study focuses to enhance the workflow of the waste characterization process at an MRF. A solution named Smart Sight is proposed to detect and classify waste based on videos recorded after processing MSW through a mechanical sorting line consisting of bag breakers and trommel screens. A comprehensive dataset is created encompassing thirteen mixed waste classes from single and multi-family streams. The dataset is preprocessed with motion compensation techniques and frame differencing methods to extract and refine valuable frames. A one-stage YOLO detector model is then trained over the dataset. The experimental results show that the proposed method works efficiently at detecting and classifying waste objects in indoor MRF environments. Accuracy, precision, recall, and F1 score related to the proposed solution are found to be 0.70, 0.762, 0.69 and 0.72, respectively, with a mAP@0.5 of 0.716. The proposed approach is validated using data collected from local MRF by comparing the estimated waste composition values of the proposed solution with laboratory results obtained through current standardized industrial practices. Comparison reveals that waste characterization estimation obtained is consistent with the laboratory results, inferring that Smart-Sight is a viable tool for estimating waste composition.

CFD–DEM Simulation of Heat Transfer and Reaction Characteristics of Pyrolysis Process of MSW Heated by High-Temperature Flue Gas

Pyrolysis is a promising disposal method for municipal solid waste (MSW) due to the high-value utilization of the organic components of MSW. Traditional indirect heating has low heat transfer efficiency and requires an increase in the heat exchange area. In this study, a refined numerical simulation model for the pyrolysis of four typical MSW components with high-temperature flue gas was established to study the influence of flue gas on the heat transfer and reaction characteristics of MSW. The temperature distribution and particle size change in different components were obtained, and the effects of flue gas temperature and velocity on the pyrolysis process were analyzed. It was found that the temperature difference of the four components along the bed height direction was about 1.36–1.81 K/mm, and the energy efficiency was about 55–61%. When the four components were uniformly mixed, the temperature increase rates of each component were similar during the pyrolysis process. As the flue gas temperature increased, the amount of gas consumption decreased and the energy efficiency increased. When the flue gas velocity increased, the flue gas consumption increased and the energy efficiency decreased. The research results are of great significance for the promotion and application of pyrolysis technology to MSW with high-temperature flue gas.

Distribution of gasification products and emission of heavy metals and dioxins from municipal solid waste at the low temperature pyrolysis stage.

Gasification is widely regarded as one of the most practical, economical, and environmentally friendly waste disposal technologies for municipal solid waste (MSW). The pyrolysis stage (300-500°C) is crucial for weight loss during MSW gasification, as a considerable amount of organic matter breaks down, producing high-value synthesis gas. This study investigated the product distribution and pollutant emission characteristics within this temperature range and its influencing factors during MSW gasification using a self-designed MSW gasification device. Results indicated that MSW underwent approximately 70% weight loss within this temperature range, yielding low amounts of inorganic and short-chain organic products, with mainly long-chain organic compounds of C16-C34. The atmosphere variation had minimal effect on the elemental composition and content of solid phase products. X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) analyses showed that Mn and Zn were the primary components of heavy metal leaching toxicity in solid phase products, with their contents increasing as temperature increased. Synthesis gas showed the highest content of heavy metal As element, reaching a peak at 400°C. Higher gasification temperature and lower oxygen flow rate significantly reduced the dioxin content and I-TEQ values, with highly chlorinated isomers being the predominant dioxin isomers. Nonetheless, low-chlorinated dioxins accounted for more than 50% of the I-TEQ. This study improves our understanding of the gasification process of MSW.

SOLVING ENVIRONMENTAL PROBLEMS BY RECYCLING MUNICIPAL SOLID WASTE

Multifaceted human activities are accompanied by the release of large amounts of greenhouse gases into the atmosphere, which is one of the reasons that can lead to disruption of natural processes occurring in the atmosphere. About 80% of greenhouse gas emissions come from industrial processes. Increasing concentrations of greenhouse gas emissions into the atmosphere, as well as lack of recycling or improper disposal of waste, can upset the balance of the ecosystem. In addition to industrial waste, municipal solid waste (MSW) is a source of greenhouse gas emissions into the atmosphere. When solid waste is used as a renewable energy source, significant amounts of carbon dioxide are released into the atmosphere. In this regard, the disposal of solid waste waste and subsequent processing can play a certain role in solving a serious environmental problem that concerns all of humanity. The article is devoted to the issue of environmental problems caused by the accumulation of MSW, which can become potentially dangerous for environment and human health. The objective of the study was to study the possibility of using fractions separated by a large MSW processing center operating in the country as secondary raw materials, as well as developing an environmentally friendly method for processing MSW for their disposal. The possibility of transforming the organic component, separated by sorting during solid waste disposal, into organic-mineral fertilizers has been studied. To neutralize the raw organic component of MSW from helminths, mineral waters of Azerbaijan were used, coming to the surface at a temperature of 25-75°C, containing 5-18% H2S As a mineral component of the fertilizer, phonolite is used, which is part of the rock of volcanic origin in the Lerik region of Azerbaijan, containing potassium, necessary for the development of plants. To eliminate the acidity of the resulting pulp before granulation, local shell rock was used. The neutralized organomineral component of MSW was mixed with pre-crushed phonolite until the nutrients were completely transferred into the pulp, followed by drying in an oven for 1.5-2 hours at a temperature of 100-110°C. The resulting mass was cooled for 30 minutes to ripen, then shell rock was added. During the processing process, organic compounds present in MSW undergo hydrolytic destruction. A technological process has been developed for producing potassium-containing organomineral fertilizer by processing the organic component of solid waste using local natural resources, which is protected by an AR patent. Keywords: ecology, waste management, municipal solid waste, recycling, organomineral fertilizers.

Study on the Co-gasification characteristics of biomass and municipal solid waste based on machine learning

Co-gasification of biomass and municipal solid waste (MSW) exhibits synergistic effects by improving the quality of syngas while reducing environmental pollution from MSW. In this study, Machine learning (ML) techniques were employed to investigate the co-gasification process of biomass and MSW. A comprehensive dataset was constructed using existing data, including different feedstock types and operating conditions, with 18 input features and 9 output features. Four advanced ML models were utilized to model and analyze the co-gasification process. By leveraging feedstock characteristics and operating parameters, key gasification parameters such as syngas composition, lower heating value (LHV) of syngas, tar yield, and carbon conversion efficiency were predicted. The results showed that all four models exhibited excellent predictive performance, with R2 values greater than 0.9 in both the training and testing stage. Specifically, Histogram-based gradient boosting regression (HGBR) exhibited the lowest root mean square error (RMSE) in predicting CO, while the gradient boosting regressor (GBR) achieved the best performance in H2 prediction with a RMSE of 1.6. The most influential input features for CO concentration were equivalence ratio (ER), oxygen content in biomass and hydrogen content in biomass. The key features affecting H2 concentration were steam/fuel and ER.

Municipal solid waste gasification by hot recycling blast furnace gas coupled with in-situ decarburization to prepare blast furnace injection of hydrogen-rich gas

Waste-to-energy is one of the most effective methods to save energy and reduce carbon emissions. This paper proposes a novel process of municipal solid waste (MSW) gasification by hot recycling blast furnace gas (BFG) coupled with in-situ decarburization to prepare blast furnace injection of hydrogen-rich gas. MSW gasification by the hot BFG is conducted by using Aspen Plus software coupled with equilibrium model or kinetic model. Compared to the equilibrium model, kinetic simulation results exhibit good agreement with the experimental results. Moreover, the technological analysis is also performed to investigate the coupled effects of gasification temperature, MSW/BFG ratio, and steam/MSW ratio on the H2-rich syngas generated from MSW gasification. The results reveal that all the investigated influencing factors have been found with a significant effect on the H2-rich syngas formation. The 25.95 vol% of H2 and 37.20 vol% of CO during MSW gasification by the hot BFG are achieved at a gasification temperature of 900 °C, steam/MSW ratio of 0.46 kg/kg, and MSW/BFG ratio of 0.34 kg/Nm3.

Application of biodrying with hot air aeration system to process solid waste into rdf

Biodrying is a promising method to process municipal solid waste (MSW) while generating refuse-derived fuel (RDF) output. Recent developments in the process of generating refuse-derived fuel (RDF) have led to a renewed interest in minimal pretreatment processes. Although extensive research has been carried out, one of the most significant current discussions about generating refuse-derived fuel (RDF) using biodrying methods is that it has taken a long time to process. The biodrying method using air from the atmosphere takes 21 days to convert solid waste into RDF. As a result of this, Biodrying processes need to be accelerated by flowing hot air into the biodrying reactor. The aim of this study is to analyze the biodrying process temperature profile with a hot air aeration system. The methodological approach taken in this study is to circulate the hot air that comes from the combustion of wood charcoal. Hot air is discharged into solid waste that is inserted into the biodrying reactor. The temperature and concentration of solid wastewater are analyzed every 15 minutes. The results of this study show that the initial MSW temperature of the front reactor was 40o C and that of the rear reactor was 31o C.In the first 15 minutes until 60 minutes, the temperature shows an increase. The MSW temperature of the front reactor was 47o C, and the rear reactor was 35o C.At the 30th minute of the front reactor, it was 63o C, the rear reactor was 61o C; at the 45th minute of the front reactor, it was 81o C, the rear reactor was 73o C; and at the 60th minute of the front reactor, it was 80o C, the rear reactor was 79oC. These findings have significant implications for the understanding of how circulate the hot air aeration system works well.

Особенности образования и использования твердых отходов в Республике Беларусь

The purpose of the work is to justify the priority of processing municipal solid waste over other solid waste. The methodology chosen is the analysis of statistical data characterizing the generation and use of solid waste in Belarus. It has been established that over 60% of solid waste in the Republic is generated as a result of the activities of OJSC Belaruskali, which specializes in the extraction of potassium salt and the production of mineral fertilizers. These production wastes are characterized by a low level of danger and are sent for temporary storage. Only 1.6% of all production waste generated is subject to burial, which in world practice is recognized as the least desirable method of disposal. Municipal solid waste accounts for about 6% of the mass fraction of all generated solid waste. However, the municipal solid waste segment accounts for 86% of all waste disposed of in landfills. There is a trend towards an increase in the share of municipal solid waste use from 9% in 2010 to 30% in 2021, which means a general decrease in the volume of waste disposal in Belarus. The growth in the use of municipal solid waste is hampered by its complex morphological composition, therefore, before using waste, it is advisable to sort it or separate collection. To improve monitoring of waste generation and use in Belarus, some additions to the existing statistical system of environmental indicators are also proposed.

The concept of a closed resource cycle using an innovative information system for the development of bioenergy

RELEVANCE. The impossibility of using existing information systems, such as territorial waste management schemes (TSOs) to form a balance of supply and demand. TSOs do not allow us to identify the volume of demand and supply for processing technologies, and equipment manufacturers are not focused on understanding the balance of demand across the country. Technological development in terms of creating new facilities for energy waste processing requires justification of prospects for investment.THE PURPOSE. Develop the concept of a closed resource cycle using information flows aimed at identifying participants in the process. The desired tool should provide an understanding of the need for the production of bioenergy equipment, the potential for demand for R&D, as well as the formation of state programs to support the creation of enterprises for the processing of municipal solid waste (MSW) and the production of bioenergy equipment.METHODS. The development of the concept of a closed resource cycle is characterized by the design of the concept, which includes the methods of divergence, transformation, and convergence.RESULTS. The paper describes the relevance of the topic associated with the impossibility of using existing information systems such as territorial waste management schemes (TSMS) to form a balance of supply and demand for processing technologies. Potential participants in the formation of a closed resource cycle throughout the life cycle of a waste processing project are identified, with the role of participants and the links between them, as well as the characteristics of the information flow of each participant, identified. A concept is proposed based on the formation of an information system in which each participant can maximize their needs for resources and effect.CONCLUSION. The proposed system makes it possible to improve the existing waste management system, ensures the return of generated waste to the resource cycle. systems - the balance of generated and recycled waste. The main difference between the proposed system and the federal state information system for accounting and control of waste management of classes I and II is the principle of operation - the system is based on the source of waste generation, ensuring the balance of generating and processed waste.

Recycling of Municipal Solid Waste in Construction

This article discusses a promising direction focused on the use of recycled municipal solid waste in construction. In Russia, there are problems related to municipal solid waste management, which necessitates the modernization of this process and confirms the relevance of the issues raised. Analysis and use of the experience of foreign countries in the processing of municipal solid waste and its secondary use in Russia contributes to the search for a more environmentally responsible approach that entails both economic and social benefits. The use of solid municipal waste recycling products in construction is aimed at minimizing the negative impact on the environment and is a step towards the transition to a circular economy, where waste is turned into valuable resources. The article reflects on the various methods of recycling municipal waste and analyzes the priority areas for the processing of municipal solid waste. In addition, examples of successful building projects using recycled products are given, and the challenges and prospects of this approach, as well as its significance for sustainable development and environmental responsibility in the construction industry, are revealed.

Importance of Microalgae and Municipal Waste in Bioenergy Products Hierarchy—Integration of Biorefineries for Microalgae and Municipal Waste Processing: A Review

In the context of global advancements, the imperative of a sustainable energy supply looms large. Biomass, an adaptable and renewable resource, has garnered attention for its potential contributions, although economic uncertainties persist due to the intricate web of processing pathways. In response, the biorefinery concept emerges as a structured strategy to optimize the processing of microalgae and municipal solid waste (MSW), capitalizing on their multifaceted potential to yield diverse end-products. This review underscores the critical significance of a cohesive biorefinery paradigm that unites the processing of microalgae and MSW, unveiling their capacity to generate a spectrum of high-value products. The utilization of mixed-integer linear programming paves the way for an optimal biorefinery model that navigates through complex decisions. Challenges encompass the array of diverse feedstocks and the preliminary nature of data availability. The overarching goal of this research is to discern optimal pathways for the conversion of MSW and microalgae into energy and valuable products, with a focus on enhancing waste utilization and augmenting the energy supply. In the broader landscape, this comprehensive review advances strategies for sustainable energy generation and waste management, invigorating innovative approaches to shape future progress. By illuminating pathways towards maximizing the potential of biomass resources, this review contributes to the ongoing discourse on sustainable energy and waste utilization.

Application of the AM2 Model to Simulate Anaerobic Digestion of Municipal Solid Waste

Anaerobic digestion is a promising technology due to its significant economic and environmental potential. Nevertheless, its development is a substantial challenge for researchers since this biochemical process is difficult to predict due to the many reactions involved. Thus, mathematical modeling becomes necessary to analyze the fermentation process and determine the complex kinetic parameters to identify and predict the system's performance under the most varied conditions. This research aims to apply the AM2 model to simulate the anaerobic digestion process of municipal solid waste. The experimental results obtained from our previous research work were used for identifying the parameters of the AM2 model and for its validation by the cross-validation method. Simulations showed that the model could effectively reproduce the dynamics of the evolution of the anaerobic digestion process with reasonable accuracy.

Processing municipal solid waste incineration bottom ash for integration into cement product manufacture

Municipal solid waste incineration (MSWI) bottom ash (BA) contains the elemental composition necessary for cement and concrete production and is a feasible substitute for high-value markets such as cement kiln feed (CKF) and supplementary cementitious material (SCM), providing an opportunity to recycle materials that are typically landfilled. This study explores the physical and chemical properties of individual components of MSWI BA—glass, ceramic, concrete, and slag—for use in cement product manufacture. Elemental oxide data reveals MSWI BA contains a variable composition of elements necessary for clinker formation. For example, MSWI BA concrete has a calcium content (33–40%) similar to that of limestone (64%) used in CKF. Compressive strength of mortar made with MSWI BA glass and ceramic is about 75% that of the control. Elemental analysis and isothermal calorimetry confirm that MSWI BA glass and ceramic fractions have the strength and elemental composition for use as an SCM compared to slag and concrete.

Legal Problems of Environmental Information in the Management of Solid Municipal Waste

The article reveals some problems of legal regulation of the solid municipal waste management system and the elimination of accumulated environmental damage in terms of the elimination of unauthorized locations of solid municipal waste and landfills of solid municipal waste. The importance of the measures and rules adopted by the state to ensure the implementation of environmental protection projects to eliminate accumulated environmental damage, as well as to reduce the negative impact on the environment and human health, the importance of improving legislation in terms of ensuring access to environmental information in the field of education, processing, disposal and disposal of municipal solid waste is noted. Particular attention is paid to the need to establish transparency of the state environmental management aimed at implementing an Environmental Safety Strategy, one of the main issues of which is the creation of an integrated system for the management of solid municipal waste and the elimination of accumulated environmental damage.The direct dependence of ensuring environmental safety and achieving the indicators of the national development goals of the country on the transparency of environmental information generated during the management of solid municipal waste and the elimination of unauthorized landfills of solid municipal waste has been established. The article also touches upon some issues of coordination of the activities of public authorities that ensure the formation of a sustainable system of solid municipal waste management, and the importance of environmental information in the framework of building interdepartmental cooperation in this direction.

Thermodynamic analysis of a sorption-enhanced gasification process of municipal solid waste, integrated with concentrated solar power and thermal energy storage systems for co-generation of power and hydrogen

A system of coupled CO2 capture and gasification has led to a new concept entitled sorption-enhanced gasification (SEG) which can increase H2 concentration in the syngas composition. This study proposed a novel configuration of the SEG system comprising concentrated solar power and thermal energy storage systems. Calcium looping (CaL) is utilized as the CO2 capture process. Unlike conventional SEG systems in which calcination heat demand is supplied by an oxy-combustion process, this study considers a heliostat field to provide heat for sorbent regeneration. The solar and thermal energy storage systems are simulated dynamically to achieve accurate results. A steam Rankine cycle is also designed to recover the released heat sources through the SEG system. The overall system performance is explored through energy and exergy analyses. Based on the results, the proposed system managed to produce 0.58 kg/s pure hydrogen in addition to 13.96 MW of net electrical power. Meanwhile, CO2 is captured from syngas composition with capturing efficiency of 95%. The energy analysis shows cold gas efficiency and the annual total energy efficiency of 87.76 and 70.74%, respectively. Based on exergy analysis results, the carbonator reactor exhibits the highest permeance compared to the gasifier and calciner reactors, with an exergy efficiency of 88.74%. Parametric study results show an increase in the cold gas efficiency, hydrogen production rate, and electrical energy efficiency with enhancing steam-to-biomass ratio. An increase in CO2 capture efficiency also improves both the electrical energy efficiency and H2 concentration of the syngas composition. CO2 capture efficiency and S/B ratio are inversely related to the exergy efficiency of the system.