Experimental Study Of Flow And Pre-Separation Characteristics In The Spraying Bed Flue Gas Desulfurization

Pollutants Pollutants emissions from coal burning power plants cause seriousinfluence on environment,economic development and human health.Technology offlue gas pollution control is an effective way to solve the problem. With the developmentof flue gas pollution control technology, researchers and users widely consider and searchfor an efficient and economic removal technology which is used to control both fly ashand SO2, and even an integration removal process. Based on the traditional semi-dry fluegas desulphurization, it has special advantages of developing integration removal processcontrolling both fly ash and SO2. A scale CFB-FGD installation aiming to removal SO2and fly ash was designed and built, and resistance characteristics and pressuredistribution of the spraying bed reactor, resistance characteristics and separationcharacteristics of the blinds pre-separator was experimentally studied in this paper.In this paper,the research focuses at the spraying structure of Venturi, squareriser, inner circling enhanced structure at the top of the reactor .Beside of analyzingresistance characteristics, the axial pressure distribution and fluctuations of the reactorwas detected by pressure sensor. The effect of the axial particle concentration distributionof reactor by changing operating parameters was analyzed through comparing pressurechanges. The results show that: Venturi structure is a major part of the response to thepressure loss, and its single-phase tests accounts for 75% of whole resistance loss; for thetow-phase tests, in the upper reactor increases, but resistance of Venturi structure stillaccountes for about 68% of whole resistance loss. When the superficial gas velocityapproaches to 7.5m/s,particle concentration in the reactor is relatively high, and whenthe superficial gas velocity is 7.5-8m/s, the pressure volatile fluctuate is strong, whichmeans large mixing intensity.The effect of changing system operating parameters and Blinds geometricparameters to Blind separation characteristics was searched, including its separationefficiency, resistance, particle size distribution. The results show that: Blind separatorachieves a low resistance and high efficiency separation at low speed and highcirculationflow rate; Blade angle has small impact on the separation efficiency andresistance; with the increase of blade pitch, the separation efficiency and resistancedecreases. Only layout separate baffle can also achieve a relatively good separationefficiency. When the length of baffle is 200mm, the separation efficiency is at its max point, which is about 74.2%.