Research On Filter Performance Of New-type Granular Layer Filter

Advanced coal fired combined cycles, such as IGCC and PFBC-CC are perspectives in future, because of their high efficiency and minimum environmental pollution. Gas cleanup facilities are necessary to protect the gas turbine and environment. Hot gas cleanup is an important aspect of technology improvement aspect of technology improvement for efficient IGCC and PFBC-CC systems. As a kind of high-efficient dust removal technology, granular filtration is able to bear the high temperature, corrosion-resistant, does not fire exploding, filtering ability advantage of influencing more than the resistance by the dust etc, considered to be one of the greatest potential hot dust removal technology at present. On the basis of analyzing each characteristic of fixed granular bed and moving granular bed, this paper developed a new fixed granular bed which realizes filtering and dust cleaning in succession.According to medium hydrodynamics, macroscopic equations and governing equations of filtering in the fixed granular bed were proposed, and formulas of dust concentration in airflows, variation of dust deposit density and dust removal efficiency of the fixed granular bed was deduced. Based on the law of filtering in the fixed granular bed, combining the characteristic of the new fixed granular bed, equations of variation of dust deposit density, dust removal efficiency and dust concentration in exit was given.In view of the characteristic of the new fixed granular bed, based on the theory of the fixed granular bed, the impact of various kinds of parameters on performance of the fixed granular bed and variation of dust deposit density was studied through the systematic experiment, which verified the theory of the fixed granular bed. Through the experiment of combined fluidized bed dust cleaning, the influence of the state of fluidized bed on the material dust removal was studied; the fluidized speed of dust removal was fixed. On this basis, in different filtration of the wind speed,medium,time and the thickness of the fixed bed and the cycle of dust removal, the systematic experiment and function test of the new fixed granular bed was carried out, receiving the influence law of many kinds of parameters to the performance of the dust remover. The result demonstrated that the new fixed granular bed is a high-efficient dust removal device.