Experimental Study On Msw Fluidized Bed Gasification And The Prediction Model

The development of society and economy has consumed large numbers of energy and increased the yield and the energy value of municipal solid waste(MSW) dramatically. That's the reason why to develop a property method to make a good use of MSW is a great problem that the whole world is facing. Incineration was one of the most essential way of MSW disposal due to its significant volume and weight reduction and highly efficient of energy recovery. With the increasing requirements of environmental protection, improving of MSW incineration process to reduce pollutant emissions is the main direction of the development of MSW incineration technology. MSW gasification and melting technology has been referred as the second generation of waste incineration technology, it's a combination of low temperature gasification and high temperature melting achieved significant reduction of dioxin, heavy metals and other pollutants emission. In Japan and other developed countries a trend have been shown that the incineration was replaced by gasification and melting system.Under thus context, this paper start from the study of the possibility if the MSW gasification and melting system can been applied in China. Aspen Plus was used to simulate the MSW gasification and melting process of representative Chinese MSW for the calorific value of 4000kJ/kg,5000kJ/kg and 6000kJ/kg respectively. The influence of air coefficient, air preheat temperature and moisture content were discussed. A special flow Chinese MSW gasification and melting system with dry and high temperature air preheat was developed which is suitable for MSW with the calorific value of 5000kJ/kg and moisture content of 60%.After the feasibility study, pyrolysis characteristic of the typical components of MSW was studied by TG/FTIR, the pyrolysis behavior and products was discussed. A special designed facility was used to study the pyrolysis behavior and products of MSW typical components at a higher heating rate. By comparing these data, the influence of heating rate on the pyrolysis was discussed.A 10kg/h fluidized-bed gasifier was used to carry out the experiments of fluidized-bed gasification of both single component and their mixtures. The mass and energy distribution of products were discussed as well as the influence of temperature on the composition of the product. In addition, by comparing the weighted sums and the experimental data, the possible interactions and its impact were discussed. The study of the fluidized bed gasification of simulated MSW and the generation characteristics of dioxin by different PVC content and air ratio was studied.Based on experimental studies, a gray theory methods was used to analyze the correlations of the composition, operating conditions with the gasification characteristics. And a higher degree correlation parameters was used as the input data, to establish and predict the products of MSW gasification by the prediction model build by artificial neural network.