Journal of Material Cycles and Waste Management

Air pollution control residues (APCr) from municipal solid waste (MSW) incineration are hazardous waste, and their management requires holistic approaches within technical, economical, legislative, and environmental constraints. This work deals with the recycling of APCr for producing lightweight aggregates (LWA) commonly manufactured by firing natural clay. The main objectives are to evaluate the environmental impacts of LWA with and without incorporating APCr and assess whether APCr recycling in LWA is beneficial, based on the life-cycle assessment (LCA) methodology. The system boundary included raw material extraction, grinding, mixture, firing, cooling, and packing (cradle-to-gate). Results were analysed following the impact assessment methods recommended by the International Reference Life Cycle Data System. Results pointed out a reduction of impacts in all categories when 3% of natural clay are replaced by APCr. The highest gains occurred for toxicity categories (HTc, HTnc) and resulted mainly from avoiding landfill of APCr. For non-toxicity categories, impacts were dominated by the emissions from the kiln firing process, which were similar for both LWA; therefore, impact reductions from APCr use in LWA in these categories were modest. LCA results show that the valorisation of APCr in LWA may be an environmentally sound solution to avoid landfill disposal practices.

The incineration of food waste water in conjunction with the domestic waste is getting attention as a food waste water treatment method, due to its low treatment cost and high efficiency. Many studies verified that the ammonia in the food waste water served as a reducing agent to suppress the generation of NOx when the food waste water was injected and incinerated. However, they have not revealed the correlation between the change in the concentration of the CO and NOx by the influence of the solid matters contained in the food waste water on the incineration of the wastes. The purpose of this study is to determine the optimum amount of the food waste water injected through four nozzles in the primary and secondary incineration chambers and to assess the correlation between the concentration of CO and NOx in accordance with the food waste water injection in each chamber of the incinerator. For the study, four food waste water injection nozzles were installed; two (A and B) at the top of the primary incineration chamber and the other two (C and D) in the secondary incineration chamber. The correlation between the change in the concentration of CO and NOx was studied adjusting the amount of the food waste water injected through the nozzles. From the result, Case II showed the concentration of CO and NOx as 1.8–10 and 14–26 ppm, respectively, while Case I showed that of CO and NOx as 15–30 and 9–18 ppm, respectively. Those levels are well below the Korean emission criteria, 50 ppm for CO and 80 ppm for NOx. Based on the results, it is evident there is a certain trade-off between emission of CO and NOx, and Case II which has relatively low concentration of CO is easier and cheaper to control.

Waste management contributes to renewable energy such as biodiesel production from processes of various types of biomass including vegetable oils, animal fats, and waste of edible oil. Successful waste management effort is influenced by people concern about benefit of waste management including for renewable energy from biomass. It involves their understanding initiated by literacy on biomass energy. To help increase literacy on waste recycle and biomass energy technology, we study readability of online information regarding biomass energy in Indonesian language (Bahasa Indonesia). Indonesia is considered as one of biomass-rich country with a little utilization for energy. The readability is studied by combining two approaches: measurement by readability standard and survey on readability confirming measurement by the standard. This study focuses on the confirmation survey readability standard measured on biomass online information in Indonesian language. In the survey, 19 online text materials were read by respondents and they were asked to give their impression whether the texts are easy or difficult to understand. From this study, what factors influence understandability of text information are shown. The results could be a guidance for preparing text information to raise people concern on waste recycle and renewable energy in general.

The stocks and flows of silver throughout the Asian economy for 1997 have been quantified, with major flows examined over their entire life cycle, including mining, production, fabrication, and manufacture, product use, and waste management. By compiling the findings of 11 country-level material flow analyses, a regional analysis was created. The reliability and availability of the data varied, with the most confidence given to the earlier life stages and the most uncertainty existing later. Overall, Asia is a net importer of silver, requiring nearly 7000 Mg of silver in 1997. Approximately 2200 Mg Ag are mined, and production waste totals about 640 Mg Ag. The flow of silver into use equals 9900 Mg Ag, with a considerable build-up of 7100 Mg Ag entering in-use stock. Silver waste sent directly to the environment, in addition to landfilled waste, totals 1600 Mg Ag. Much variation exists when examining country-level silver flows on a per capita basis. India and Thailand’s fondness for silver jewelry greatly increases their silver flows into use and in-use stock. Japan’s high overall consumption reflects its high GDP per capita. Regionally, a significant potential exists to tap the silver contained in the in-use stocks and to enhance the recycling rates.

This study investigates solid-waste handling practices by municipal waste collectors during COVID-19 pandemic period in Osogbo urban areas with the intention of assessing measures put in place for preventing possible spread of the disease. Data for the study were obtained from primary and secondary sources. Primary data were acquired through questionnaire administration on the 5% of waste collectors selected through snowball technique of chain referral. Data collected were analyzed using descriptive statistical methods. Adopted under this technique are cross-tabulation, percentages, index that was used determine waste generation (WGI), and protective material index (PMI) used by waste collectors before and during the lockdown periods. The result showed that rate of waste generation before the pandemic was WGI = 0.69 and during the pandemic was WGI = 0.75. The use of protective materials before COVID-19 was PMI = 2.9 as against (PMI = 3.58) during the lockdown period, with face mask recorded lowest occurrence of use (PMI =  − 2.91). Crude materials that cannot guarantee the safety of waste collectors are used for transfer of waste into disposal vehicle. The study concludes that solid-waste collectors in the study area are not adequately catered for during COVID-19 pandemic.

The objectives of this study were to assess the physicochemical, nutrient, and spectral properties of biochar prepared from four major agricultural residues of India [rice straw (RSB), wheat straw (WSB), maize stover (MSB), and pearl millet stover (PSB)] at three (400, 500, and 600 °C) pyrolysis temperatures. Pyrolysis temperatures and residue types profoundly influenced biochar properties, for instance, PSB biochar had the greatest pH (10.75 ± 0.01), calcium carbonate equivalent (CCE) (47.8 ± 0.5), and carbonate (CO 3 = ) content (432 ± 17 meq kg−1). Irrespective of residue, greater pyrolysis temperature improves the biochars’ acid-neutralizing capacity by increasing pH in water (pHw), CCE, and CO 3 =  content. The CCE of biochar showed a significant positive correlation with pHw (R 2 = 0.51, p < 0.001) and ash content of biochar (R 2 = 0.54, p < 0.001). A great amount of water-soluble potassium (20.6–29.5 g kg−1) in all the biochars made them suitable for supplying potassium to plants. Infrared spectroscopy explained the functional group formation, while XRD revealed mineral formation in the biochar. Thus, depending on the requirement, diverse properties of biochar can be prepared by designing residue type and pyrolysis temperature suitable for application in a specific soil to alleviate nutrient deficiency and improve soil productivity.

Due to the recent developments of improved production methods of 2,5-dimethylfuran, (known as DMF) from waste biomass, it is being considered as a next-generation biofuel. Energy content of DMF is comparable to that of gasoline. Test data available in the literature for its behavior in SI engines are limited. Therefore, in present work, a comparative evaluation of physico-chemical properties and engine performance of 5 % blend of DMF in gasoline (v/v), with gasoline and 10 % blend of ethanol in gasoline (v/v) has been carried out. Results show that 5 % blend of DMF in gasoline (v/v) offers a comparable performance and lesser tail pipe emissions than gasoline.

The accumulation of floatable litter load captured in gross pollutant trap (GPT) due to the hydrological runoff has become challenging due to rapid development and alteration of land use changes. The application of soil conservation service curve number (SCS-CN) method has been widely used to estimate the direct runoff from the given rainfall especially when there is no runoff measured within the catchment. The results found that there was enormous variation on floatable litter load between different months and individual GPT. There was a high accumulation of floatable litter load on August 2015 with 495 kg/month and at K17 with 510 kg. Both of these conditions was significantly influenced by rainfall depth, hydrological parameters such as initial abstraction, potential maximum retention, and average weighted curve number (CNaw) values from different types of land use within their respective catchment area for individual GPT. Thus, the outcomes from this study can be very useful and beneficial for related government agencies and various stakeholders in ameliorating this critical and challenging environmental issue in terms of operation and management; technical operation; the selection of GPT prior to installation in other areas including the design, costs and maintenance.

This study focused on the waste separation behavior of households in areas with a waste separation at source (WSS) program to understand the effect of the program and identify suggestions for improving the participation rate. A questionnaire survey was conducted through face-to-face interviews with 402 households in Da Nang City, Vietnam. To measure the effect of the WSS program on waste separation behavior, the authors conducted a comparison between waste separation behavior before and after implementing the program. The authors developed a model of waste separation behavior to clarify the factors. The differences in participation rates and influencing factors as they related to respondents’ level of involvement in the WSS program were also examined by Chi-squared test and ANOVA. The participation rate before the WSS program was 70.0% for plastic bottles, 70.1% for cardboard, and 71.4% for aluminum cans. After the WSS program, these rates significantly increased by 14.2% for plastic bottles, 12.6% for cardboard, and 12.3% for aluminum cans. Through behavior modeling, the factors influencing waste separation behavior were clarified. The attendance of respondents at an explanatory meeting and the recognition of the leaflets would positively promote the participation rate and the factors influencing waste separation behavior.