Abstract
Effective management, utilisation and conversion of municipal solid waste (MSW) to useful energy (Waste-to-Energy) could be a potential means of providing a sustainable and environmentally friendly solution. There are many types of waste-to-energy technology that can be chosen for application. The aim of this paper is to propose a tool called the Quantitative Index for Waste to Energy Technology Selection with the purpose of assisting users in screening before selecting the most suitable technology for converting MSW to energy in term of safety and health parameters. There are three components developed under both safety and health parameters. In safety parameters, the components are flammability, explosiveness and toxicity while in health parameters the components are volatility, material state and occupational exposure limit (OEL). A set of scores representing the level of hazards is assigned to these components through the application of logistic function. After all components in both parameters have been scored, the scores are added together and the maximum scores produced are taken to present the safety and health parameters for each technology called the Safety Score and Health Score. Both safety and health scores are then added together to produce a single score representing the technologies called the Safety and Health Total Score (SHTS). Lower score indicates the technology as preferable in term of safety and health parameters than the technology with higher score. This technique was applied to a simple case study of four waste-to-energy technologies which are landfill gas recovery system (LFGRS), waste incineration, gasification and anaerobic digestion. According to the assessment made, anaerobic digestion is the least preferred technology while LFRGS is the most preferred technology in term of SHTS. Further analysis showed gasification scores the highest in Health Score due to the existence of carbon monoxide as the by-product which has high volatility and low OEL indicating workers will have more exposure to carbon monoxide. Anaerobic digestion scores the highest in Safety Score due to the existence of hydrogen sulfide that is highly flammable and very toxic. Additional assessment in terms of economy, energy and environmental needs also to be included for a comprehensive assessment.
