| Peanut shell as a crop waste every year in our country abundant, some for feed and wood-based panel industry, most of them is discarded or burned directly, causing a waste of energy. With the accelerated process of urbanization, more and more municipal sewage sludge is produced, and how to dispose the sludge is a problem that people pay more and more attention to. High sulfur anthracite is not only produced in some areas of relatively scarce coal resources, but also has been widely used in the local area, causing serious environmental pollution. In this paper, peanut shells as raw materials, adding sludge binder, high-sulfur coal, to preparation a new peanut shell briquettes in small molding pressure by cold techniques.In this paper, we first study the basic characteristics of the basic raw materials as the research object. Study the physical properties of the molding fuel, and optimize its molding process. Through the thermal analysis technology, the pyrolysis and combustion weight loss of the molding fuel were studied, the pyrolysis and combustion characteristic parameters and kinetic parameters were analyzed and calculated. Through the simulation of the actual boiler combustion, study the combustion performance of the briquette, and optimize the combustion process.Through the research on the basic fuel characteristics, the content of peanut shell volatile was the highest, which was 64.04%. So it is easy to catch fire in the early stage, and the combustion performance is better. The low calorific value of sludge is 4334 k J/kg, and the content of volatile matter is between the peanut shell and coal. The content of volatile matter of high sulfur anthracite was the lowest, which was 8.91%, the highest fixed carbon content was 52.30%, which the calorific value was 17582 k J/kg. Add sticky sludge solution while adding a certain amount of coal can not only improve the overall shape of the fuel heating value, so similar to lignite and briquettes burn time can be extended to strengthen post-combustion intensity. The peanut hull has the lowest melting point, and the softening temperature is 1193 degrees centigrade. The ash fusion point of sludge and coal is high, and the amount of sludge and coal can be added to increase the melting point.According to the physical properties of the molding fuel, it can be known that the molding effect is best when the molding pressure is 50 k N, the content of sludge is 20%, the content of coal is 10% and the water content is 8%. According to the thermal analysis results showed that the sludge content 20%, coal content is 10%, the heating rate is 30 ?/min, the pyrolysis and combustion effect is the best. The fitting coefficients are larger than 0.98 in the kinetic analysis, so the reaction process can be described by the first order reaction. When the sludge content is 20%, the content of coal is 10, the heating rate is 10? /min, the activation energy of pyrolysis and combustion is minimum. Based on the simulated boiler combustion test results show that, the sludge content was 20%, coal content is 10%, and the temperature is 1000?, excess air coefficient is 1.5, the rate of combustion is maximum. And the effect of furnace temperature on the burning rate of briquette is the biggest. The ash melting point of the molding fuel is between 1200 to 1100?, and belongs to the soluble ash. In the process of combustion, the furnace temperature is controlled to be less than 1100 ?, and the smoke exhaust temperature is controlled below 1000?. |
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