Solid Waste Processing Research Articles

The influence of the chemical composition of the hardened auger on its wear during dehydration process of municipal solid waste in the garbage truck

The article is dedicated to the study of the influence of the chemical composition of the hardened auger by the chromium on its wear during dehydration of solid waste in the garbage truck. Using the rotatable central composition planning of the experiment of the second order by means of the Box-Wilson method, the dependencies of auger wear depending on the chemical composition of the hardened steel and friction path are determined. The responce surfaces of the objective functions are shown – the wearing of the hardened steel and energy consumption of the dehydration process by the hardened auger press of the mixed municipal solid waste according to the influense parameters. It is established that on the friction path s = 56850 m, during the dehydration process of solid waste in the garbage truck, the simultanuous incresing of the carbon content from 0.45% to 2.1%, and the chromium content – from 0.25% to 12%, at the optimum content of the manganese as 0.527% in the hardened steel of the auger, enable to decrease the energy consumption of the dehydration process of solid waste by 25.7 kWh/tons, or 10.7%. Therefore, it tends to cheaper the process of dehydration in the garbage truck. It is established the expediency of further research for the determination the rational composition and the structural state of the auger material and the ways to increase its wear resistance.

Development of technology for processing solid waste from the production of orthophosphoric acid into an inorganic composite material

The article considers the processes of processing solid waste from the production of phosphoric acid - phosphogypsum - into composite inorganic materials. It is shown that heat treatment at a temperature of 1073 K leads to the formation of inactive calcium sulfate. Carrying out the heat treatment process under similar conditions in the presence of an organic reducing agent is accompanied by the formation of a composite material with a luminescent ability. A simple method for the disposal of large-tonnage production waste with the production of a demanded product is proposed.

Static and dynamic characteristics of rotary kiln reactor during processing of biomass and municipal solid waste

The behavior of five types of material (wood pellets, agro pellets, over-sieve fraction (OSF), willow chips and alder chips) in rotary kiln reactor was tested. Basing on the obtained experimental results, the empirical mathematical models were validated to predict mean residence time (MRT). The best fitted correlation generated mean absolute error at level of MAE = 9.4%. Regarding dynamic characteristics, the simplified approach of “first-order + dead time” was successfully applied to model the dynamic characteristic of rotary kiln reactor in terms of solid phase mass flow rate. The characteristic parameters of dynamic model, i.e. τ, min and Θd, min, were determined for every case. Time constant, τ, was in the range of 5.8–34.3 min, whereas dead time, Θd, was in the range of 0.001–73.2 min. Finally, a simplified model to estimate the time (i.e. 3 × τ + Θd) necessary to obtain steady-state conditions in terms of mass flow rate in rotary kiln reactors was proposed.

Migration behavior of impurities during the purification of waste graphite powders

Metal-laden solid wastes (e.g., waste graphite powders) have attracted great attention owing to their hazardous effects on the surrounding soil and water. Additionally, the metal-bearing impurities also hinder the reutilization of waste graphite powders. Thus, it is necessary to remove these inorganic impurities and figure out the removal mechanism of impurities in the purification process. In this study, an alkaline roasting-water washing-acid leaching (AWA) method was used to upgrade the waste graphite powders, and the migration behavior of diverse impurities has been qualitatively and quantitatively investigated. A graphite product with high impurity removal efficiencies is attained under optimal conditions. The removal of impurities mainly follows three routes: (1) V-, P-, and S-bearing impurities were complete removed (some formed soluble salts during alkaline roasting, and the remainder was dissolved in acid); (2) most Al-, K-, and Si-bearing impurities were removed by alkaline roasting, with the remainder was dissolved in the acid-leaching process; and (3) Fe-, Mg-, Ti-, Ca-, and Zn-bearing impurities were decomposed at high temperature and reacted with alkali to form hydroxides or oxides, which was subsequently dissolved in acid. In addition, the treatment of the generated wastewater is also discussed. The uncovered migration mechanisms of diverse impurities would guide the purification and reutilization process of other metal-bearing solid wastes efficiently.

Challenges and opportunities of utilizing municipal solid waste as alternative building materials for sustainable development goals: A review

Strict environmental concern, depletion, and price hike of building construction materials are driving scientific studies for the search of alternative materials for building construction. To this end sustainable building materials could be a fruitful solution. This review aims to discern the environmental efficacy of solid waste management (SWM) and its relationship with four stimuli i.e., economic structure, regulatory structure, science, and time. The study also highlights the investigation of governance network to figure out the regulatory structure and governance of waste management. Extensive details on solid waste with their sources, recycling potential and their current utilization for substantial development are outlined. A throughout of the production process, properties, advantages, disadvantages, and the global economy of building material developed through recycling of solid waste are discussed. This article also deals with the sustainability, social, and environmental impact of green building materials. The study identifies the future direction for the effective utilization of solid waste for developing building materials. Further, the scope of the present also focusses on the concept of circular economy for developing construction materials through recycling of solid waste, which provides an easy reference for solid waste processing towards sustainability.

Technologies for valorization of municipal solid wastes

AbstractMunicipal solid waste (MSW) consists of the waste obtained from various sources like households, industries, municipalities and other commercial areas. Common landfill and incineration strategies are insufficient to process the waste generated on daily basis. Municipal solid waste contains significant amounts of organic carbon (50–60%) that has great potential for the production of fuels and value‐added products. This review discusses the composition of the organic fraction of municipal solid waste (OFMSW) and waste processing strategies that enable organic carbon recovery compared with conventional methods. Changes in the composition of MSW worldwide and the factors influencing it in various regions are discussed in this study. The processing of diverse OFMSW through thermochemical methods such as incineration, gasification, pyrolysis, torrefaction and hydrothermal carbonization is discussed here with the results of densification or gasification of the organic carbon, enabling its chemical transformation. Additionally, the combined methods, where OFMSW is pre‐treated followed by enzymatic hydrolysis for the conversion of OFMSW to monomeric sugars have also been described. Globally, to ensure sustainable solid waste management and efficient carbon recycling, combined methodologies seem more appropriate. The study also attempts to list the different attempts across the globe that highlight this concept of the transformation of waste into materials and chemicals, improving its commercial value. The commercial success of such OFMSW processing attempts can provide momentum for establishing sustainable treatment technologies and reaping profits, laying the groundwork for a strong and complete carbon‐recycling environment and circular carbon‐based economy. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd

Stabilization of organic municipal solid waste by composting

The article examines the process of vermicomposting of municipal organic waste. To determine the optimal composition of bio humus, various options and proportions of mixing organic waste with soil are considered. In the course of the study, three different variations of organic waste were developed, mixed with manure: 1 — soil, paper, vegetables, fruits, wood waste, cow manure (1:0.5:1); 2 — soil, vegetables and fruits, wood waste (1:1); 3 — soil, cow manure (1:1). The results of the experiment showed that all substrates have high germination of tomato seeds. However, a mixture of soil, paper, vegetables, fruits, wood waste, cow manure increases the yield of tomatoes by 11 % compared to other experimental substrates. Vermicomposting E. was performed using E. fetida worms. This kind of worms is characterized by high yield. For vermic content, the moisture content must be at the level of 60 %. Bacteria also play an important role in vermicompost. With air humidity below 40 %, their activity decreases and stops at temperatures below 10 %. In this experiment, solid organic waste processing technology reduces the shortage of cheap organic fertilizers in the market and offers new opportunities for profit for small enterprises. The results obtained can be used for processing organic waste of the city on an industrial scale and applied as fertilizer in agriculture.

The influence of the alloying of the auger by the chromium on its wear during dehydration process of municipal solid waste in the garbage truck

The article is dedicated to the study of the influence of the alloying of the auger by the chromium on its wear during dehydration of solid waste in the garbage truck. Using the method of regression analysis, the hyperbolical dependencies of auger wear depending on the chromium content in its hardened steel for different values of the friction path are determined. Graphical dependences of augur wear depending on the chromium content in its hardened material as a function ​​of the friction path are made up, and it confirms sufficient convergence of the obtained dependencies. Carried out additional regression analysis allowed to determine that that during two weeks of operation of the auger during dehydration of solid waste in the garbage truck increasing of the chromium content in its hardened material from 0.25% to 12% reducing the speed of the wearing and energy consumption of solid waste dehydration from 12.2% to 3.1%, and, consequently, to reduce the cost of the process of their dehydration in the garbage truck. It is shown the graphical dependence of the reduction of energy consumption of dehydration of solid household waste by the hardened auger due to its alloying by the chromium. It was established the expediency of further research to determine the rational content and structural state of the material of the auger and the ways to increase its wear resistance.

Odour Load of Selected Elements of the Technological Line at a Municipal Waste Biogas Plant

Technological processes associated with municipal solid waste (MSW) processing are a potential source of odorant emissions, i.e., substances that cause negative olfactory impressions. When released into the atmosphere, these substances can cause odour nuisance complaints from residents. Many scientists have noted the strong relationship between odorant emission sources and odour concentrations and their significant impact on the living comfort of residents near these sources, as well as their social and economic relations. This paper attempts to estimate the odour load of selected elements of the technological sequence of a biogas plant processing municipal waste. Odour load was characterised by four constituents: odorant emissions, odour emissions, the variability of these emissions, and the emission levels per 1 Mg (1000 kg) of waste. The highest odour emissions accompany the storage of mixed MSW, which is associated with a large amount of waste. Limiting the storage time of waste should be an indispensable part of the technological regime. The dominant odorant associated with mixed MSW storage is NH3 emissions. The greatest variability of odorant and odour emissions concerns gases captured from selectively collected waste plastics and metals, due to the varied forms of selective waste collection in the service area, and their unstable efficiency. High variability of NH3 and odour emissions also accompanies digestate dewatering.

Calculation of the high-level waste maximum activity of the Chornobyl NPP operating origin during storage in KTZV-0.2 containers

This paper decrypts the conceptual design of the cask’s control radiation system of high-level waste (HLW). This system is intended for the solid radioactive waste processing plant at Chornobyl NPP and is capable of forming a passport for a batch of HLW, based on the measured surface dose rate (DR) for KTZV-0.2 protective container. DR for primary packaging and KTZV-02 container were calculated using Monte Carlo simulation code MCNP 6.2. The typical material compositions of the Chornobyl NPP radioactive waste, contaminated by 137Cs and 60Co, were considered, and the corresponding surface DR was calculated. The simulation results were used for the development of the HLW cask load criterion for the radiation loading control system. The paper shows that HLW load criterion could be safely increased from 80 to 280 mSv/h.

Bio-Augmentation as an Emerging Strategy to Improve the Textile Compost Quality Using Identified Autochthonous Strains

The present investigation is devoted, for the first time, to the potential of autochthonous inoculums through bio-augmentation tests to improve the compost quality and to decrease the composting time during composting of textile waste. For this reason, three strains were isolated from a mixture of textile waste, green waste, paper, and cardboard waste, and therefore identified as Streptomyces cellulosae, Achromobacter xylosoxidans, and Serratia liquefaciens, employed using bio-augmentation test. The organic matter decaying was assessed according to three different inoculums doses, separately and in consortium (4%, 6%, and 8%), to describe the effect of bio-augmentation process on the organic matter decaying. Indeed, these three strains and their consortium have shown a strong potential of organic matter degradation, equally the bacterial consortium showed a total organic carbon degradation of 20.3%, total Kjeldahl nitrogen of 1.52%, and a Carbon/Nitrogen ratio of 13.36. Compost maturity has been completed after only 12 weeks of treatment instead of 44 weeks using the classical treatment by composting. Ultimately, according to these results, bio-augmentation could be an emerging and promising strategy to accelerate the composting process of solid waste, especially in the case of industrial waste. Equally, it could be an effective tool to avoid the accumulation of industrial waste disposal in public landfills and/or nature while allowing their treatment.

Processing of low-density waste in fluidized bed made out of lightweight expanded clay aggregate

The main aim of the study is to obtain a new, innovative method for the organization of combustion processes in fluidized bed reactors. A key aspect of the change in the organization of the fluidized bed combustion process is the creation of a fluidized bed made out of lightweight expanded clay aggregate (LECA). The new fluidized bed has a density of 0.5 g/cm3, therefore, allowing for thermal processing of low-density solid and liquid industrial wastes, as well as waste biomass. Polyolefins (polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, and polypropylene homopolymer) were selected as examples of low-density solid wastes. The use of an innovative fluidized bed for liquid waste degradation was studied on the example of glycerol combustion. Waste wood chips were chosen to represent low-density biomass. Thermal degradation of selected materials in the fluidized bed made out of LECA was carried out at a temperature range of 500–900 °C with an interval of 100 °C. Video analysis of the fluidized bed surface proved the sinking of waste materials into the bed and significant elimination of diffusion flames in the freeboard. Qualitative and quantitative flue gas analysis was carried out using the FTIR spectrometer. More than 95% conversion of the carbon contained in the polyolefins to CO2 was achieved already at 700 °C. At 500 °C, more than 30% of the polymeric carbon left the reactor as aromatic compounds. To avoid the emission of harmful aldehydes during the thermal processing of glycerol, the bed should be heated to at least 800 °C. Waste wood chips as an alternative fuel can be thermally incinerated in the fluidized bed made out of LECA. The disappearance of volatile organic compounds and CO emissions occurred at 700 °C and 800 °C.

Evaluation of thermal plasma process for treatment disposal of solid radioactive waste

The management of radioactive waste is a worldwide activity based on the guidelines of the International Atomic Energy Agency (IAEA), and all stages of management require scientifically proven methods for possible deployment. The management of radioactive waste is a huge challenge due to the high risk in the collection, gathering, transport, handling, and storage. In this study, a thermal plasma treatment process was evaluated for its efficiency to process solid radioactive waste. Experiments were carried out with the application of stable isotopes of Lead, Iodine, Cobalt, and Cesium. After the thermal plasma treatments, the slag and the residual gas were analyzed to verify the influence of process time and discharge power on the efficiency of the process. The treatment for 25 min and 10 kW was sufficient to reduce the mass by 50% of the slag. When the applied power was increased to 15 kW, an expressive reduction in the treatment time (10 min) was able to promote the same mass reduction. The results indicated that the treatment of radioactive waste by thermal plasma is a promising method to manage and reduce the mass and volume for the final disposal.

Problems of investing in enterprises for processing and disposal of solid municipal waste

The issues of investing in enterprises engaged in the utilisation and processing of municipal solid waste are currently relevant due to increasing consumption, correspondingly increasing production and the amount of waste and require the most careful approach from the point of view of environmental security. The object of the research are the factors that determine the potential benefits of investing in enterprises of this industry. The methodological basis of the study was сompiled by general scientific methods of knowledge and the special scientific methods arising from it: logical, analytical, comparative analysis method, and information processing statistical methods. The authors present growth indicators in dividend payments and stock prices of individual American companies that provide services for the processing and waste disposal from those companies that operate in the residential sector, industry, and municipal organisations. The negative factors, hindering investment in this sector in Russia, have been reflected. The research results show the new development potential for the recycling and waste management industry.

Producing feed protein by bioconversion of domestic and industrial organic solid wastes using Black Soldier Fly (BSF) larvae

The bioconversion of organic solid waste utilizing Black Soldier Fly (BSF) larvae was used to reduce the unstable domestic supply of feed protein in Indonesia due to currency change dynamics. BSF larvae are a well-known bioconversion agent capable of producing high protein content in their body mass. Therefore, this research aims to conduct a small-scale bioconversion process of domestic and industrial organic solid wastes to produce dry BSF larvae as a protein source for chicken and fish culture. The research was held at Bogor, Indonesia, from March-June 2021, where organic solid waste from a restaurant was bioconverted by BSF larvae in a biopond. After two weeks, the BSF larvae were harvested, dried, and milled to produce the powder. Based on SNI 7548:2009, the quality of pellets from BSF larvae and pupae was appropriate, except for the parameters of fat content in pellet A and water and ash content in pellet B. The results showed that fish pellets mixed with 20% protein flour affected the weight growth of Pangasius sp. Furthermore, when dried BSF larvae powder was applied to one-day-old chickens, they grew somewhat quicker than the standard feed menu. Therefore, organic solid waste, when appropriately managed, produces feed protein.

Pyrolysis-Based Municipal Solid Waste Management in Poland—SWOT Analysis

Poland’s management of municipal waste, which amounts to over 13 million tons/year, is not efficient—about 60% of the waste is subjected to recovery processes, about 20% of all municipal waste is converted into energy, and almost 40% is landfilled. The authors of this article recognize the potential of pyrolysis as a method of the thermal processing of waste allowing the potential of the energy contained in the waste to be utilized. Pyrolysis is an economically attractive alternative to incineration, with a significantly lower environmental impact, allowing efficient waste management and the use of pyrolysis by-products in the energy sector (pyrolysis gas), or in the building materials sector (biochar). Despite so many advantages, this method is not employed in Poland. The aim of the paper is to indicate a recommended strategy for the application of pyrolysis in Poland as a method of the thermal processing of municipal solid waste. SWOT (strengths, weaknesses, opportunities, threats) analysis was used as a research method. In the first step, on the basis of the literature review, the factors which may affect the use of pyrolysis in Poland were identified. In the second step, five experts evaluated the weights of those factors and the interactions between them. The products of the weights and interactions allowed, in accordance with SWOT analysis methodology, the most desirable strategy of pyrolysis application in Poland to be determined, which turned out to be an aggressive one. This means that pyrolysis as a thermal waste processing method should be implemented on a large scale in Poland to improve the indicators of municipal waste management.

Sustainable processes for treatment and management of seafood solid waste

Seafood processing is an important economical activity worldwide and is an integral part of the food chain system. However, their processing results in solid waste generation whose disposal and management is a serious concern. Proteins, amino acids, lipids with high amounts of polyunsaturated fatty acids (PUFA), carotenoids, and minerals are abundant in the discards, effluents, and by-catch of seafood processing waste. As a result, it causes nutritional loss and poses major environmental risks. To solve the issues, it is critical that the waste be exposed to secondary processing and valorization for recovery of value added products. Although chemical waste treatment technologies are available, the majority of these procedures have inherent flaws. Biological solutions, on the other hand, are safe, efficacious, and ecologically friendly while maintaining the intrinsic bioactivities after waste conversion. Microbial fermentation or the actions of exogenously introduced enzymes on waste components are used in most bioconversion processes. Algal biotechnology has recently developed unique technologies for biotransformation of nutrients, which may be employed as a feedstock for the recovery of important chemicals as well as biofuel. Bioconversion methods combined with a bio-refinery strategy offer the potential to enable environmentally-friendly and cost-effective seafood waste management. The refinement of these wastes through sustainable bioprocessing interventions can give rise to various circular bioeconomies within the seafood processing sector. Moreover, a techno-economic perspective on the developed solid waste processing lines and its subsequent environmental impact could facilitate commercialization. This review aims to provide a comprehensive view and critical analysis of the recent updates in seafood waste processing in terms of bioconversion processes and byproduct development. Various case studies on circular bioeconomy formulated on seafood processing waste along with techno-economic feasibility for the possible development of sustainable seafood biorefineries have also been discussed.

IoT-Enabled Smart Waste Management Systems for Smart Cities: A Systematic Review

With urbanization, rising income and consumption, the production of waste increases. One of the most important directions in the field of sustainable development is the design and implementation of monitoring and management systems for waste collection and removal. Smart waste management (SWM) involves for example collection and analytics of data from sensors on smart garbage bins (SGBs), management of waste trucks and urban infrastructure; planning and optimization of waste truck routes; etc. The purpose of this paper is to provide a comprehensive overview of the existing research in the field of systems, applications, and approaches vis-à-vis the collection and processing of solid waste in SWM systems. To achieve this objective, we performed a systematic literature review. This study consists of 173 primary studies selected for analysis and data extraction from the 3,732 initially retrieved studies from 5 databases. We 1) identified the main approaches and services that are applied in the city and SGB-level SWM systems, 2) listed sensors and actuators and analyzed their application in various types of SWM systems, 3) listed the direct and indirect stakeholders of the SWM systems, 4) identified the types of data shared between the SWM systems and stakeholders, and 5) identified the main promising directions and research gaps in the field of SWM systems. Based on an analysis of the existing approaches, technologies, and services, we developed recommendations for the implementation of city-level and SGB-level SWM systems.

Fungi Dekomposer Penghasil Enzim Ekstraseluler Lakase, Mangan Peroksidase, dan Lignin Peroksidase dari Kawasan Kebun Raya Bogor: Isolasi, Seleksi, Identifikasi dan Kajian Aktivitas Enzimnya

This study aimed to obtain the candidate isolates of superior decomposer from several plant block areas in the Bogor Botanic Gardens (KRB). Those candidates were expected to be able to utilize in the fermentation process of solid organic waste. The superior decomposer fungi candidates were selected based on their abilities to produce extracellular enzymes (laccase - Lac, manganese peroxidase - MnP, and lignin peroxidase - LiP) using 0.05% guaiacol as a substrate. The highest abundance of decomposer population was found in the block 4 with 9.9 x 106 CFU ml-1, and the lowest in block 6 with 1.9 x 106 CFU ml-1 density. Three superior decomposer isolates were obtained, namely KRB 3.1 (from block area 3), KRB 4.6 (from block area 4), KRB 6.7 isolate (from block area 7). The KRB 6.7 isolate has the highest Lac and MnP enzyme activities, as the following 24.10 U ml-1 and 186.3 U ml-1, while KRB 3.1 isolate from block area 3 has the highest LiP activity with the value 598.57 U ml-1. According to the molecular analysis, those candidate isolates of superior decomposers were identified as Coriolopsis hainanensis (KRB 3.1 isolate), Polyporus thailandensis (KRB 4.6 isolate), and Cerrena aurantiopora (KRB 6.7 isolate). Those are potentially used as the decomposers in solid organic waste fermentation.

SOLID WASTE MANAGEMENT ISSUES AND CHALLENGES

Urbanization and population growth are solely responsible for high and increasing rate of solid waste and its proper management is a major problem of Municipal Corporation of every city. Solid waste from households is a serious health hazard and leads to the spread of infectious diseases. Solid waste is the unwanted or useless solid materials generated from human activities in residential, commercial or industrial areas. As we know Solid waste management involves managing activities associated with generation, storage, collection, transfer and transport, processing and disposal of solid wastes. Solid waste problem is big issues at present time, if this problem is not tackled within preventive time, it may create other dreadful, hazardous and incurable problems. In this study, the sources and components of solid waste, type and the quantity of solid waste disposed, methods of solid waste disposal and its impact on health were highlighted.