Solid Waste Sorting Research Articles

External Factors Impacting Residents’ Participation in Waste Sorting Using NCA and fsQCA Methods on Pilot Cities in China

Recycling waste is important as it can help to reduce environmental pollution caused by "waste siege". Source classification is an important part of the municipal solid waste (MSW) sorting process. The factors that prompt residents to participate in waste sorting have been debated by scholars in recent years; however, there are not many papers that focus on the complex relationships between them. This study reviewed the literature that concerns residents' participation in waste sorting, and it summarized the external factors that might influence residents' participation. Then, we focused on 25 pilot cities in China, and we analyzed the configuration impact of external factors on residents' participation using a necessary condition analysis (NCA) and a fuzzy-set qualitative comparative analysis (fsQCA). We found no consistency between variables, nor was there one single condition that caused residents to participate in waste sorting. There are two main methods (environment-driven and resource-driven) that can help achieve a high participation rate, and three methods that can cause a low participation rate. This study provides suggestions for the implementation of waste sorting in other cities in China, as well as developing countries, with an emphasis on the importance of public participation.

Quantitative evaluation of waste sorting management policies in China’s major cities based on the PMC index model

Municipal Solid Waste governance in China entered a new phase in March 2017 when the Chinese government began requiring major cities to enforce waste sorting as well as to develop a system of laws, regulations, and standards regarding waste sorting. This study used text mining and the Policy Modeling Consistency (PMC) Index model to develop an evaluation system of Municipal Solid Waste sorting management policies that included 10 first-level variables and 51 second-level variables to quantitatively evaluate the texts of waste sorting management policies in 11 major cities, and then the PMC surface of policy texts was constructed to analyze the strengths and weaknesses of individual policies according to the PMC index values. The results revealed that there were no excellent level or bad level policies among the 11 policies, with an average PMC index value of 7.71. Overall, the 11 policy texts all set out clear goals and programs in accordance with local conditions, but there are some differences across policies in terms of indicators, including policy content, policy function, policy evaluation, restriction and incentives. This study provides a fresh viewpoint on the policy evaluation of waste sorting management and offers some insight for policymakers, who should pay attention to waste separation, focus on key indicators of the policy, and enhance the effectiveness of the policy response. In addition, the applicability of the evaluation model and the difficulties associated with waste sorting governance of China in post-epidemic are discussed.

Household waste sorting practice, and factors associated with sorting practice in Bedelle town, Southwest Ethiopia.

Household solid waste generation rate in low-income countries is increasing due to population growth and changes in people's lifestyles. Sorting waste into categories is an important step in household waste management. However, there is limited information about sorting practices in a low-income setting like Ethiopia. Therefore, this study aimed to assess household solid waste (HSW) sorting practices, and factors associated with sorting practices.A community-based cross-sectional study was conducted from April to May 2021 in Bedelle town. Households were randomly selected, and household heads were interviewed using a pre-tested questionnaire. A total of 209 households were included. The proportion of households that practice waste sorting was calculated. Logistic regression was used to assess the association between HSW sorting practices and associated factors. A P-value of less than 0.05 was declared as significant. The Hosmer and Lemeshow tests were used to check for model fitness.The result of the study shows that the proportion of householders who practiced waste sorting practice in the setting was 21.53%. The sex of the household head, information on sorting benefits, and the availability of private waste collectors for resource recovery were factors in practicing waste sorting at the household level. Accordingly, male-headed households are 88% less likely to practice sorting practice than female-headed households, and those having access to information on waste sorting benefits are 3.68 times more likely to practice sorting, and similarly, households, where private waste collectors are active, are about 4 times more likely to practice waste sorting at the household level than their counterpart. This finding calls on the municipality to create awareness about solid waste sorting practices at the household level, involving both male and female householders in waste management and mobilizing waste collectors at the household level to facilitate effective waste sorting and reuse as sustainable solid waste management options in the town.

The Relationship between Knowledge and Attitudes with the Behavior of Health Workers in Medical Waste Management in Indonesia: A Systematic Review and Islamic Perspectives

During the Covid-19 pandemic, there was an increase in medical waste, especially in healthcare facilities. Medical waste, if not managed properly, will potentially pollute the environment. The behavior of health workers in managing medical waste is influenced by knowledge and attitudes. The study aimed to analyze the relationship between knowledge and attitudes with the behavior of health workers in managing medical waste in Indonesia using a systematic review approach and according to an Islamic perspective. This study uses the method of literature review and systematic review. The selection of articles used the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) method on the Google Scholar journal website. Search for articles with the keyword "Medical and Behavioral and Bivariate Waste." Articles were selected based on the 2020-2022 year of publication and a cross-sectional research design. The results of filtering articles using the PRISMA method obtained ten articles. The behavior of health workers in managing medical waste from the ten articles includes disposal of solid medical waste, management of medical waste, segregation of medical waste, disposal of medical and non-medical waste, management of solid medical waste, and sorting of solid medical waste. Nine articles show that there is a significant relationship between the knowledge and behavior of health workers. Eight articles show a significant relationship between the attitudes and behavior of health workers. The review of the Islamic religion concluded that health workers must have a trustworthy nature, work ethic, responsibility, and accountability. Health workers are also required to maintain personal hygiene and the environment.

Development of a mathematical model of the process of sorting municipal solid waste using elements of similarity of technical systems

The article studies the similarity of ensuring the technical condition of the solid municipal waste sorting line system. The functional dependence of the productivity of the waste sorting line is given, partial expressions and numerical values of the criteria for similarity of the functioning of the sorting process are obtained. A generalized criterion of similarity of the state of the solid municipal waste sorting process is also obtained, the nature of the influence of the parameters of functional dependence on the value of the output characteristic is investigated.

Sorting, Logistics and Secondary Use of Solid Household Waste in Ukraine on the Way to European Integration

Sorting, Logistics and Secondary Use of Solid Household Waste in Ukraine on the Way to European Integration

Model and method of solid household waste sorting for their effective thermal disposal

The work considers the development of a simulation model and an automated method of sorting solid household waste based on the identification of a portion of the studied raw material with further classification according to accepted groups of characteristic chemical composition. A method of classification of municipal solid waste (MSW) and a method of their identification was proposed, which made it possible to identify groups that produce acid gases. The basis of the method is a simulation model, which is represented by a tabular form of the gross formulas of possible compounds. The identified compounds are identified both qualitatively by the isoenthalpic method and quantitatively by the express gravimetric method. The sequential chain of identification makes it possible to search for substances that form acid gases during further processing by thermal destruction methods. A method of sorting solid household waste has been developed for the possibility of further processing of each group with maximum efficiency and compliance with ecological indicators. The method is based on: technological method of sorting; the method of sorting raw materials-processing in which measuring devices are integrated to ensure the specified characteristics of identification according to the classification features of the simulation model; the principle of using measuring devices depending on the type of identification task by qualitative or quantitative indicator.

MSWNet: A visual deep machine learning method adopting transfer learning based upon ResNet 50 for municipal solid waste sorting.

Supplementary material is available in the online version of this article at 10.1007/s11783-023-1677-1 and is accessible for authorized users.

Intelligent solid waste sorting management indicators from source AL Shua’la district

The developed world has made great strides in implementing sustainable development in its three dimensions, environmental, economic and social, because of its great importance in preserving its natural resources. The developing countries of the world must keep abreast of all developments in science and apply them in their countries to enjoy a sustainable life. The research reached results, including the problem of large quantities of solid waste resulting from the large population in the AL Shua’la district in the capital, Baghdad, which was not treated sustainably manner. Solid waste in the study area is collected and transferred to the sanitary landfill, without sorting from the source, or recycling which has economic and environmental benefits, the economic benefit is if the sorted waste is sold in the local waste market, and it is possible to benefit from the return The financial result of sorting from the source in developing the efficiency of the waste sorting service, while the environmental benefit is to reduce pollution. The research recommended conducting a sorting plan from the source. Awareness campaigns should be carried out for the population about the importance of sorting at the source and the establishment of recycling plants sufficient for recyclable waste.

Thực trạng quản lý chất thải rắn y tế và một số yếu tố ảnh hưởng tại viện Y Dược học Dân Tộc thành phố Hồ Chí Minh năm 2020

Objectives: This study has two objectives as the follows: to describe the management situation medical solid waste management and some factors affecting of solid medical waste management at the Traditional Medicine Institute Ho Chi Minh City by 2020. Methods: This is a cross-sectional descriptive study, combining quantitative and qualitative method. medical solid waste storage tanks, medical solid waste transportation vehicles, medical solid waste storage area at 13 clinical and subclinical with 130 times of classifying and collecting, 52 times of transporting, 16 times of storage and 13 times returning to medical equipment. Information gathered through 4 in-depth interviews with 4 leaders of the Institute, department, department and 3 group discussions. Qualitative data was collected from 04 in-dept interviews and 03 focus groups discussion. Main findings: The research results show: sorting of medical solid waste at source and non-communicable hazardous medical solid waste must be put into a black bag / bin reaching=90%; in the stage of medical solid waste collection: the content of not collecting medical solid waste together reaches 92.3%; medical solid waste is transported according to the prescribed road, reaching 92.3%; Medical solid waste content that does not contain the same barrels and in solid medical waste warehouses must have a centralized waste container with a lid in accordance with regulations, all reaching 93.7%. The Institute has 4 medical solid waste warehouses that fully comply with the regulations on the management of medical solid waste, only not meeting the warehouse area. Key words: Solid medical waste, influenced factor, Traditional Medicine Institute Ho Chi Minh City.

Impact of the profile of public-private partnership projects on the economic potential of Central Asian countries

The object of this study were projects based on public-private partnership. The results of the state of public-private partnership projects in various sectors of the economy of the Central Asian countries and the assessment of the prospects for their development are presented. The study uses a comparative public-private partnership project and a forecast analysis of the economic performance of the economies of the Central Asian countries. A comparative analysis revealed the predominant areas of public-private partnership projects. The Republic of Kazakhstan is ahead of other Central Asian countries in the implementation of public-private partnership projects with a total cost of USD 2. 863 billion. There are 136 projects in the Republic of Uzbekistan, dominated by the sphere of housing and communal services (collection, removal, sorting, and processing of solid household waste) and the field of culture and sports. There are three agricultural projects in the Kyrgyz Republic. In the Republic of Tajikistan, 32 projects are being developed, mainly aimed at the development of transport infrastructure. Turkmenistan is implementing two projects related to transport infrastructure and manufacturing. Forecast analysis of economic indicators of countries makes it possible to identify the prerequisites for the use of market mechanisms to improve the agriculture of countries and the prospects for development from implementation for the agro-industrial complex of the Republic of Kazakhstan. The most important task of the strategic development of countries with commodity economies is to increase food security. The creation of favorable conditions for the development of economic relations between the state and the private sector is inextricably linked with the need to provide state support measures and legal regulation

Vibrational classification of secondary material resources. Industrial applications

The article considers various approaches aimed to increase versatility and ensure improvement of the existing vibrational classification equipment and technology in order to achieve higher capacity, equipment utilization, and process indicators. It is shown that one of the main methods to ensure higher reliability of classification equipment (such as vibrating screens) is to improve the vibration drives. This allows obtaining a higher equipment utilization factor by increasing the net operating time under process load over long operation periods from the existing value of 0.92–0.93 up to 0.97. Capacity improvements for vibrating screens used in the processing of minerals and metal powders may be ensured through the use of screening surfaces of complex shapes, including by applying both the traditional coarse-to-fine screening sequence and the reverse fineto-coarse sequence with the use of vertical or inclined sieves. A complex screening surface arrangement was successfully implemented in the design of a vibrating screening separator for the primary sorting of municipal solid waste (MSW). With equal performance in terms of initial MSW capacity and power consumption, the proposed separator weighs 4 to 7 times less, while its sorting efficiency for the target fractions is 2–2.5 times greater than that of traditional trommels. It also eliminates film material clogging of screening surfaces, which is a typical operational disadvantage of all trommel screens.This study was carried out with the financial support of the Russian Science Foundation (project No. 20-79-10125).

Management of classified municipal solid waste should focus on odor pollution and ozone formation potential caused by VOCs

VOCs, generated during municipal solid waste sorting, collection, transportation and treatment, are important causes of odor pollution and ozone formation. Sampling was conducted at 11 sampling sites in Suzhou waste stream 1 (other waste from a residential quarter, a transfer station, and a landfill) and waste stream 2 (kitchen waste from a residential quarter and waste from an anaerobic digestion plant). VOC emissions were mainly from the anaerobic digestion plant (31.8 mg/m3) and transfer station (22.9 mg/m3), while the emissions from the residential quarter and landfill were relatively small (from 113 to 982 μg/m3). Based on the theoretical value of odor potential, the anaerobic digestion plant and transfer station were also major sites of odor pollution, with ethanol, limonene, p-diethylbenzene and dimethyl sulfide as priority odor pollutants in the former and limonene in the transfer station. The anaerobic digestion plant and the transfer station also contributed most of the ozone formation potential. Ethanol, limonene and acetone were the priority pollutants of ozone formation in the anaerobic digestion plant, while it was toluene in the landfill, ethanol and limonene in the transfer station, and limonene in the kitchen waste. Anaerobic digestion plants and transfer stations should become the focus for management to reduce ozone formation potential and odor pollution. The study will provide information for theoretical value odor and ozone control of MSW and has reference value for MSW treatments in other developing areas and countries.

Analysis of the state of the solid municipal waste management system in St. Petersburg over the past 25 years

The article examines the state of the waste management system in St. Petersburg over the past 25 years. It is shown that over 25 years, the environmental damage to the waste management system in St. Petersburg has increased 2.22 times, which indicates that the system has not been practically improved over the past years. Throughout the 25 years under consideration, the bulk of the solid municipal waste generated in St. Petersburg has been exported to the landfill, which is approximately 88 % of their total amount. The remaining 12 % is processed into compost at waste recycling plants. At the moment, in St. Petersburg there is a system for collecting hazardous waste from the population, which includes: hazardous waste collection points "Ecopoints", mobile hazardous waste collection points "Ecomobiles", metal terminals for receiving hazardous waste "Ecoterminals", as well as those designed to receive spent batteries, i.e. batteries "Ecoboxes" installed in specially selected places convenient for citizens. The work of the city's hazardous waste collection system from the population has been carried out since 2010, it is being improved, and is aimed at extracting hazardous waste generated by residents of St. Petersburg from the total volume of solid municipal waste generated by them. In conclusion, it is concluded that in the future in St. Petersburg it is necessary to develop directions for reducing the amount of waste exported to landfills by separating organic fraction from the main stream of municipal solid waste coming for processing, separating hazardous waste from them, as well as using high-quality sorting and deep processing of incoming solid streams municipal waste with the extraction of useful fractions from them, which can be used as secondary raw materials and for energy production

Message Presentation Is of Importance as Well: The Asymmetric Effects of Numeric and Verbal Presentation of Fear Appeal Messages in Promoting Waste Sorting

ABSTRACT This study aimed to investigate the effectiveness of fear appeal messages to promote public engagement with municipal solid waste (MSW) sorting in China using the extended parallel process model (EPPM). By adding information format to the EPPM as guided by the construal-level theory, the study examined whether the interaction effects of threat and efficacy on behavioral intention varied in terms of verbal and numeric information format. The 2 × 2 × 2 factorial experiment revealed a significant main effect for efficacy. The threat, albeit having no significant main effect itself, moderated the effect of efficacy on behavioral intention. Moreover, the significant three-way interaction effect of threat, efficacy, and information format suggested that individuals who received low-threat and high-efficacy messages in numeric format had the highest intention to perform MSW sorting. Findings from this study imply that how messages are presented is of just as much importance as what to communicate to the public when designing environmental campaigns.

Sensor-Based Technologies in Effective Solid Waste Sorting: Successful Applications, Sensor Combination, and Future Directions.

The increase in global population and improvement of living standards have stirred up a continuous increase in solid waste generation, while simple incineration and landfilling bring about serious environmental and health concerns. In order to improve resource recovery and mitigate pollution, noncontacting and nondestructive sensor-based waste sorting systems are applied to enhance solid waste classification. In recent years, in addition to the rapid development of computer hardware, especially improvements of GPU computing capacity, complicated and efficient classification algorithms have emerged and been widely used in industrial sectors. These advances allow computers to process signals from sensors more quickly and accurately and to classify matters automatically. This article introduces widely applied sensor-based technologies in solid waste sorting and analyzes applicable conditions for each specific method. The latest developed algorithms are critically compared with competitive counterparts. Successful practices are described, and findings are highlighted. Though spectroscopic-based and vision-based waste classifications have achieved high performance in accuracy and detection speed, challenges and future directions can still provide wide development opportunities. Concretely, these opportunities generally comprise classification of indistinct plastics, application of the latest object detection algorithms, appropriate data set formulating, and sensor combination for multiple sorting tasks within a single system.

The impact of municipal solid waste sorting policy on air pollution: Evidence from Shanghai, China.

Municipal solid waste (MSW) sorting not only reduces the total quantity of domestic waste but also has positive effects on urban air quality. In this study, using a careful identification strategy and air quality data at the monitoring station level in Shanghai, we estimate the causal effect of the MSW sorting policy on urban air quality. The results show that after the MSW sorting policy was implemented, the air quality index (AQI), nitrogen dioxide (NO2) and carbon monoxide (CO) decreased significantly by 2.71%, 2.07% and 3.62%, respectively. We also find a positive spillover effect from the Shanghai MSW sorting policy on the air quality of adjacent cities. The implementation of this policy has triggered changes in residents' behaviors. However, the government needs further efforts to maintain the sustainability of MSW sorting policies.

Design and production of an automatic solid waste sorting machine with smart digital counter

Sorting of objects is the first step of a waste management process. These objects should be sorted according to the type of material for effective waste recycling. Therefore, the focus of this work is to design and produce an automated sorting machine that can be used to sort metals and non-metals autonomously. The automatic sorting machine with a smart digital counter was designed to use a microcontroller (Arduino Mega) to control the conveyor systems which consist of the conveyor support, driving unit and the driven unit. The sorting mechanisms consist of the inductive sensor, infrared Sensor and the actuating system using servo motor. The conveyor system helps in the conveyance of objects towards the sorting chute. The actuating system receives signal from the microcontroller and the device does the sorting of the objects based on their characteristics while the digital counter counts the number of metallic objects dropping into the designated cart. The time taken for the inductive sensor to sense an object, the waiting period for the servo motor to be actuated and the time taken for the counter to count after a metallic object is sensed are 1s, 2s and 1s respectively. After its development, it was tested and observed to meet the design requirements.

Nature-Inspired Search Method and Custom Waste Object Detection and Classification Model for Smart Waste Bin.

Waste management is one of the challenges facing countries globally, leading to the need for innovative ways to design and operationalize smart waste bins for effective waste collection and management. The inability of extant waste bins to facilitate sorting of solid waste at the point of collection and the attendant impact on waste management process is the motivation for this study. The South African University of Technology (SAUoT) is used as a case study because solid waste management is an aspect where SAUoT is exerting an impact by leveraging emerging technologies. In this article, a convolutional neural network (CNN) based model called You-Only-Look-Once (YOLO) is employed as the object detection algorithm to facilitate the classification of waste according to various categories at the point of waste collection. Additionally, a nature-inspired search method is used as learning rate for the CNN model. The custom YOLO model was developed for waste object detection, trained with different weights and backbones, namely darknet53.conv.74, darknet19_448.conv.23, Yolov4.conv.137 and Yolov4-tiny.conv.29, respectively, for Yolov3, Yolov3-tiny, Yolov4 and Yolov4-tiny models. Eight (8) classes of waste and a total of 3171 waste images are used. The performance of YOLO models is considered in terms of accuracy of prediction (Average Precision—AP) and speed of prediction measured in milliseconds. A lower loss value out of a percentage shows a higher performance of prediction and a lower value on speed of prediction. The results of the experiment show that Yolov3 has better accuracy of prediction as compared with Yolov3-tiny, Yolov4 and Yolov4-tiny. Although the Yolov3-tiny is quick at predicting waste objects, the accuracy of its prediction is limited. The mean AP (%) for each trained version of YOLO models is Yolov3 (80%), Yolov4-tiny (74%), Yolov3-tiny (57%) and Yolov4 (41%). This result of mAP (%) indicates that the Yolov3 model produces the best performance results (80%). In this regard, it is useful to implement a model that ensures accurate prediction to develop a smart waste bin system at the institution. The experimental results show the combination of KSA learning rate parameter of 0.0007 and Yolov3 is identified as the accurate model for waste object detection and classification. The use of nature-inspired search methods, such as the Kestrel-based Search Algorithm (KSA), has shown future prospect in terms of learning rate parameter determination in waste object detection and classification. Consequently, it is imperative for an EdgeIoT-enabled system to be equipped with Yolov3 for waste object detection and classification, thereby facilitating effective waste collection.

Recycling and upcycling in constraction

Waste is a serious environmental problem that poses a threat to the environment. The article describes the features of the use of recycling and upcycling in the construction industry. Comparison of the possibilities of these two approaches is relevant for determining effective strategies for the use of recycled materials and products in the context of the post-war reconstruction of Ukraine. Article purpose is to manifest the possibilities of using materials used in construction and their scope in load-bearing structures and decorative elements. Modern methods of handling secondary materials in construction were evaluated by the method of analysis of literature sources. Based on the comparison of existing recycling and upcycling projects for the construction of new buildings, the possibilities of using construction and demolition waste and solid waste in construction are determined.In the construction industry, waste can be used in the following ways: through the reuse of materials generated during construction and demolition and recycling — processing waste into raw materials used in the production of building materials. There is also experience of successful use in construction of municipal solid waste generated not in the construction industry — upcycling. Materials and products for upcycling in construction are either the result of creative search of customers or executors of the project, or the result of previous organized work on the collection and sorting of solid waste. Therefore, in order to spread the effective use of upcycling, it is necessary to develop a solid waste management infrastructure and disseminate successful experience in project implementation. For efficient and cost-effective recycling on a large scale it is necessary to introduce and disseminate selective demolition practices; collection and separate storage of construction and demolition waste on the construction site; recycling and disposal of materials along with construction to reduce transportation costs