Techno-economic analysis of energy recovery from municipal and industrial waste through plasma gasification

Abstract

In the UAE, municipal solid waste (MSW) is currently subjected to a low recycling rate and is mainly destined to landfill. Its plastic solid waste (PSW) fraction, on the other hand, constitute more than 20% of the unsorted fraction of the MSW. Petroleum hazardous waste (PHW) is the residual of crude oil distillation and is generated at an alarming rate in the UAE. In this work we investigate the techno-economic feasibility of plasma gasification to recover energy from the waste produced in the Emirate of Abu Dhabi. The scope of this work, is firstly to characterize these waste materials as feedstock candidates. Secondly, the software Aspen Plus is used for equilibrium based modelling at two distinct levels: the development of the gasifier model and the development of the integrated plasma gasification combined cycle power plant (IPGCC). The evaluation is based on 1st and 2nd thermodynamic laws efficiencies. Thirdly, these evaluations are then subjected to several parametrical studies involving the combined waste fractions as well as the mixed oxidizers of air, oxygen, and steam. Finally, following these evaluations an economic assessment of the plant is carried out. The results from the developed equilibrium-based model for the IPGCC plant showed that a better efficiency could be obtained compared to traditional incineration and gasification waste to energy (WTE) technologies. In particular, with a plant capacity of 2,000 tons per day, that corresponds to 40% of the total amount of the MSW produced in the Emirate in 2015, more than 128 MW of electric power could be generated with a plant efficiency of 33%, sensibly higher than the maximum efficiency of traditional WTE technologies, which is around 26%. Thanks to the extremely high temperature thermal plasma the IPGCC is superior to conventional WTE technologies as it is able to emit less dangerous pollutants, such as dioxins and furans and the inorganic fraction of the MSW is transformed in an inert non-leachable vitrified slag that can be sold as a byproduct. The economic assessment proved that a plant with a capacity of 2,000 tpd is feasible and profitable with an IRR of 14.94%, an NPV of 126 million USD, a payback period of 13.3 years. The calculated LCOE of 98 USD per MWh is very competitive when compared to that of other WTE technologies. This study was applied to the case of the Emirate of Abu Dhabi suggesting how the plasma gasification technology, in the form of an IPGCC plant, could fit well in an integrated waste management strategy to help the UAE reach its vision of 75% diversion rate from landfill by 2021.

Date of Award	May 2017
Original language	American English