Elemental analysis of residual ash generated during plasma incineration of cellulosic, rubber and plastic waste

Abstract

Management of plastic, rubber and cellulosic waste from various industries is a challenging task. An engineering scale plasma pyrolysis based incinerator has been commissioned for incineration of combustible waste, including plastic, rubber and cellulose. Operational trials of wastes with simulated composition show a weight reduction factor of more than 18 and volume reduction factor of more than 30. The volume reduction factor is tenfold higher than the compaction process currently practised for rubber and plastic wastes. Representative residual ash samples derived from these runs are subjected to their elemental analysis using EDXRF technique and results are comparable with the published literature. Relative variation of individual elements is attributed to the type of waste and feed composition. Analysis is aided with the calculation of index of geoaccumulation, enrichment factor (EF), contamination factor (CF) and pollution load index (PLI). From this study, it is evident that S, Cr, Zn, As, Se, Hg and Pb are of concern for environment in residual ash from plasma incineration of combustible waste. The efficacy of the incineration process is evaluated; C, H and O reduction achieved is more than 98% and overall enrichment ratio (ER) for the inorganic elements is more than 4.5. This study highlights the importance of elemental composition for the performance analysis of the plasma based incineration as well as hazards evaluation of constituents in residual ash for its further management.

A Review of the Impact That Healthcare Risk Waste Treatment Technologies Have on the Environment

“…This law states that no waste can be completely destroyed, no matter the characteristic of the waste. The waste that is incinerated does not disappear, however, it is transformed into different physical phases [66,67]. In the process of incineration, exhaust gases are released in the atmosphere, ash is generated at the bottom of the incinerator, and fly ash is trapped in the incinerator filters.…”

“…The end product of the incineration process, the bottom ash, contains toxic end-products of the combustion. The bottom ash is landfilled, thereby contaminating the environment in the disposal site and groundwater [66][67][68][69].…”

An atmospheric microwave plasma-based distributed system for medical waste treatment

“…Furthermore, to obtain much higher heating rates and shorter treatment times, plasma techniques are more suitable than microwave heating because plasma can instantly generate high temperatures, and these high temperatures can be controlled with millisecond-level response times. Recently, low-temperature plasma (dielectric barrier discharge and corona discharge) has been implemented in wastewater treatment, and arc plasma has been implemented in various solid waste treatments (Dam 2022 , Gao et al 2022 ; Pancholi et al 2022b ). However, these kinds of low-temperature discharge plasma have difficulty effectively “burning” solid medical waste due to its low gas temperature of ~ 300 K. Medical waste can roughly be divided into plastics and glass.…”

“…However, these kinds of low-temperature discharge plasma have difficulty effectively “burning” solid medical waste due to its low gas temperature of ~ 300 K. Medical waste can roughly be divided into plastics and glass. Thermal plasmas have proven to be an effective means of harmlessly treating and vitrifying plastic products into glassy vitreous (Pancholi et al 2022b ). However, a single arc plasma torch requires an excess of 50 kW of electric power, which occupies a large volume in the equipment (Jie et al 2022 ).…”