The Character Reach Of Nanometer Cu-Based Carring Oxygn In Generating PAHs By Coal Direct Chemical Looping Characteristic

In order to realize cleaning-production in coal industry, at the same time, optimize the energy structure in our country effectively and remission the environmental pollution problem such as global warming caused by coal combustion, in this paper focuses on the coal direct chemical-looping combustion technology, which is a kind of way that can control the emission of greenhouse gases and other pollutants by used coal effectively, and because of its clean and efficient technology characteristics, the coal direct chemical looping combustion focused by domestic and foreign scholars gradually. This experiment mainly analyzes the basic research of coal direct chemical looping combustion technology, solve the problem of the carbon deposit problems of carrying oxygen Mainly, use the nanometer CuO as carrying oxygen active ingredient innovatively and discuss the formationof PAHs in different conditions by coal direct chemical looping combustion, so as to analyze the formation of the carbon deposit in the surface of carrying oxygen. Combustion experiments to simulate the chemical-looping reduction reaction device, and preparate nano-scale CuO-based carrying oxygen. Comparing the different coal types (anthracite, bituminouscoall,2 and 3), the preparation proportion of carrying oxygen (6:4,7:3 and 8:2), burning temperature (600-1000 ℃) and the proportion of carrying oxygen/coal(2.4,2.8,3.2,3.6 and 4.0) conditions, We can know the production distribution of PAHs from flue gas by burning coal, and finally summarize the experimental conclusion:Different oxygen carriers has quite different morphological characters; compare with the non-nano-CuO based oxygen carrier, nano-CuO based oxygen carrier has more efficient catalytic conversion characteristics; Different coal types has a great influence on the formation of PAHs, and it not only has relation with the total content of volatilization in coal, but also relates with the carbon content; The contents of inert ingredients in the preparation process of oxygen carrying has great influence on the spatial structure of oxygen carrier. Carrying oxygen what have the same active ingredient generated the quantity of PAHs substances has not obviously difference, which is because the less part of inert ingredients in oxygen carrier, the more dominant position that active components occupied, and it affect the coal combustion effect mainly; It has nothing to do with the types of oxygen carriers, and the generation of tricyclic material from coal cinder shows the law as 6:4< 7:3< 8:2, witch because the oxygen enriched condition of PAHs generated can be provided by the increasing of active ingredients; With the increase of temperature, the generation of PAHs with CuO/Al2O3 carrying oxygen from flue gas decreased first and then increased,and it generating the least total PAHs in the condition of 800 ℃, however, CuO/SiO2 based oxygen carriers has the opposite generation rule with CUO/Al2O3 based oxygen carriers totally, increased first and then decreased, and it generating the maximum amount of PAHs in the condition of 900 ℃. On the whole, the PAHs generation of CuO/SiO2 based oxygen carriers less than CUO/Al2O3 based oxygen carriers, and it has a stronger catalytic conversion efficiency; With the increase of the proportion of carrying oxygen/coal, the generation of PAHs with CuO/SiO2 based oxygen carriers and CuO/Al2O3 based oxygen carriers from flue gas presents the rising tendency. This is because the excess oxygen carrier formed stack space, and inhibit the active site and fuel combustion reaction in contact, thus limiting the complete combustion of the reaction.