Abstract
Microwave-assisted pyrolysis (MAP) is an alternative
conversion method to extract the energy and produce value-added products from
solid wastes. Microwave-assisted technology has many advantages comparing with
conventional conversion methods, such as more uniform heating at molecular
level, process flexibility and equipment portability, lower thermal inertia and
faster response, low capital cost and more energy efficient. In this presentation, a continuous fast
microwave-assisted pyrolysis and gasification process and system will be
introduced. The process and system is designed, fabricated, and tested for
various solid wastes such as lignocellulosic biomass and recycled plastics. The
system is equipped with continuous waste raw material feeding, mixing of
feedstock and microwave absorbent, and a separated catalytic upgrading step. For
microwave gasification of lignocellulosic biomass, extremely high temperature
(>1200 °C) can be obtained efficiently when combining with microwave
absorbents, making the gas product much cleaner than in lower temperature and
the energy consumption much lower than that of traditional fluidized bed
gasifier. With this process, it is possible to obtain a H2-rich gas
with low tar content, and can be usable in cogeneration systems, F-T synthesis,
or fuel cells. For microwave pyrolysis of waste plastics for hydrocarbon fuel
production, the two-step microwave catalytic pyrolysis improved the bio-oil quality;
help produced the liquid product with high heating value (HHV). There are clear
potentials for commercializing the microwave-assisted catalytic pyrolysis and
gasification process and system for complete solid waste utilization.