| The hazards of municipal solid waste (MSW) on the urban environment and human health have gained great attention, whereas the traditional MSW disposal technology has been difficult to meet our need. Gasification of MSW treatment technology is a new type of waste disposal technology; it is a MSW thermal treatment and chemical process of generating combustible gases with the effect of volume reduction, and low secondary pollution and high resource utilization. Energy-saving emission reduction has become the most serious problem of the modernization of Chinese metallurgical enterprises. This paper is to explore catalytic gasification of MSW by the use of waste heat of metallurgical slag. Recycle waste heat at the same time deal with MSW.This work takes mixed solid wastes which are made up from typical components of MSW as object of the study. The process of MSW gasification has been investigated by the thermo gravimetric analysis experiments, and the characteristics of gas production have been carried out in self-designed reactor.The study showed that the process of thermal gravimetric analysis time is different while using the different samples by the use of self-designed experimental device. In the same of initial temperature and quality, copper slag with higher gas production of instantaneous response and more intense reaction to blast furnace slag. Gasification reactions happen at the surface of slag, temperature of slag surface changes more intense in the course of response, and the center of the slag with more gentle temperature changes. The particle size of the slag can also affect heat transfer. Thermo gravimetric experiment is open, subject to a lot of factors, but some factors are not isolated factors, Including buoyancy and convection, re-cohesion of volatiles, apparatus factors and specimen etc.The catalytic gasification experiment of MSW by the use of copper slag's waste heat has reaction mechanism of the three-dimensional proliferation; differential form of the function expression isY=ln((1-2/3Y)-(1-Y)2/3), while the blast furnace slag isY=ln(1-(1-Y)1/3). The catalytic gasification MSW process by the use of metallurgical slag's waste heat has smaller reaction activation energy and reaction more intense. Copper slag has a higher frequency factor and faster reaction rate. From MSW gasification kinetic equation expression da/dT=Ae-E/RT f (a), in accordance with calculated values E and A the MSW catalytic gasification kinetic model can be set up.Different initial temperature will affect the gasification reaction time of MSW. The higher onset temperature, the faster the reaction rate, the time required for complete reaction is also shorter. The cumulative gas production has nothing to do with the initial temperature when response completed, it does not change with temperature change. With the same quality of slag samples, cumulative gas production of copper slag higher than the blast furnace slag. Instantaneous peak of gas production is also lower with the onset temperature and reduced. In the absence of carrier gas, nitrogen as carrying gas and water vapor as carrying gas, gas components are carbon monoxide, followed by carbon dioxide, methane and hydrogen when the MSW has been catalytic gasified. The peak of volume fraction of carbon dioxide and methane arrival first, while the carbon monoxide later, hydrogen at the latest. The gas volume fraction of the various components is the highest when water vapor as carrying gas, followed by non-carrier gas, containing nitrogen at a minimum. To do with sand in the light of comparative experiments, the volume fraction of the various components of copper slag is the highest, followed by blast furnace slag, and the lowest is in sand. This study showed that copper slag and blast furnace slag at MSW gasification process must have some catalysis.In short, the catalytic gasification experiment of MSW is by the use of metallurgical slag's waste heat. This technology of waste disposal has better environmental benefit, social benefit and economic benefit, the development prospect is broad. |
