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In today's world of energy and environmental issues have become increasingly prominent, biomass energy as a clean and renewable energy by more and more attention, biomass power generation is showing a good momentum of development. However, in the actual biomass combustion, gasification in the use of the process, it is prone to slagging phenomenon, which has become a living biomass boilers running one of the major issues. Therefore launched an in-depth study of the mechanism of of biomass ash fusion characteristics, master slagging characteristics of biomass combustion process, reducing the likelihood of slagging living safe and efficient operation of biomass boilers to provide viable solutions to China increasing the utilization of biomass energy scale is important. The biomass ash composition of the ash melting point commenced work. Additives, washing and other experimental methods, supplemented by ash melting point measurement, SEM / EDS analysis means slagging characteristics of biomass. The specific contents are as follows: First, the basic nature of the seven kinds of biomass straw, lees, furfural residue, bagasse, corn cobs, Indus wood and shell seeds, using SEM / EDS method and ash fusion YX-HRD sexual analyzer on a variety of biomass ash characteristics. The results show that: the volatile content of biomass fuels is much higher than coal, the hydrogen content is greater, the higher oxygen content, carbon content, biomass fuels are easily ignited, but also makes the lower calorific value of biomass fuels . Great difference in the ash content of the biomass; different biomass ash in the local form there are significant differences in overall performance for the morphology various irregular particles; for most biomass gray, silicon, potassium and calcium is the major inorganic elements, and a high content of alkaline elements is low result in the ash melting point of the biomass. Secondly, biomass ash composition change, increase or reduce certain ingredients of biomass ash additives and washing test methods, and to study the melting characteristics. Through the additives trials found that sodium oxide always play a role in reducing the ash melting point; hydroxide, calcium oxide, silicon oxide, magnesium oxide, aluminum oxide ash fusion temperature of the biomass presents two sides. Biomass fluidized bed boiler should not be used quartz sand as bed material, fuel different choices of limestone, dolomite, high alumina as bed material, including limestone, dolomite the only straw fluidized bed boiler slagging suppression better. Biomass K of Ca, Cl, S, P, etc. mainly in the soluble phase exists, Na only a small amount to the ionic state, the washing effect is not very good. The ash is mainly elemental composition of the biomass, the washing efficiency descending order: Cl gt; K gt; of S gt; Fe gt; P gt; of Ca gt; Na gt; Mg. Elements K, Cl elements are the main factors causing the the biomass ash melting point of the low. Generally presents the trend first and then decreased with washing temperature rise, biomass ash melting point, optimal washing temperature is 60 ℃ ~ 70 ℃. Biomass ash melting point with increasing liquid to solid ratio rising, but when the liquid to solid ratio is too high, the ash melting point is not the straw best liquid to solid ratio of 25 (ml / g). Finally, the establishment of raw material ash composition and ash fusion temperature stepwise regression model, the model by the negative correlation coefficient test and t-test and F test. By comparison of the predicted value and the actual value of ST, the smaller the relative error of the regression model, applied to the prediction of biomass ash melting point. The study found that ash slagging discrimination index does not apply to biomass. Derived a new biomass slagging discriminant index: A = (MgO Al2O3 Fe2O3) / CaO, the proven the index is feasible. The basic biomass ash melting point ST showed an increasing trend, with the increase of A value A value less than 2.0, the biomass of serious slagging.
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