Baffle type evaporation ammonia-process desulfurization technique and device

Abstract

The invention discloses jet deflection evaporation-type ammonia process desulphurization technology and a device for implementing the same. The technology comprises a technical proposal: using ammonia as desulfurizing agent; preheating flue gas discharged by the ammonia to between 80 DEG C and 90 DEG C through a boiler; vaporizing the flue gas into steam through an ammonia evaporator so as to contact flue gas flowing from bottom to top for realizing desulphurization; carrying out demisting through a jet deflection demister, and changing the direction of demisted flue gas so as to carry out adsorption desulphurization from top to bottom through a desulphurization ring; directly discharging the flue gas after adsorption desulphurization; respectively washing the air distribution bed and the demister through an air distribution bed wash pipe and a demister wash pipe every 3 to 8 hours, so as to ensure cleanness and smoothness of an air distribution bed and the demister during desulphurization. The device mainly relates to a jet deflection evaporation-type ammonia process desulphurization tower which consists of a base, a tower body, the air distribution bed, the air distribution bed wash pipe, the ammonia evaporator, the demister, the demister wash pipe, the desulphurization ring, a flue gas inlet and a flue gas outlet. The technology and the device not only have excellent desulphurization effect, but also have an exhaust temperature as high as 80 DEG C; therefore, flue gas discharged from the device has excellent diffusibility and less smoke plume; especially importantly, because flue gas does not contain ammonium bisulphite and aerosol after adsorption desulphurization, the device can also prevent erosion in a flue and a chimney caused by wet flue gas; wash water adopted by the invention can be recycled, thereby ensuring remarkable energy-saving effect; moreover, the device has the advantages of simple structure, low operation cost and convenient maintenance.

Description

technical field [0001] 本发明涉及锅炉和燃煤设备的排烟净化技术和装置。 Background technique [0002] 我国的大气污染属煤烟型污染,中国工程院的研究报告显示,我国二氧化硫和二氧化碳排放量的85%、烟尘的70%均来自于燃煤。据统计,大气污染造成的经济损失占GDP的3%~7%,如不能得到有效控制,到2020年,仅燃煤污染导致的疾病付出的经济代价将达3900亿美元。我国二氧化硫的排放呈逐年上升趋势,酸雨面积逐年扩大。二氧化硫污染主要是由工业生产造成的,约占80%,而电力工业又是工业中的排放大户。 [0003] 目前,我国在二氧化硫控制方面所采用的技术有石灰石 / 石膏湿法、旋转喷雾干燥法、常压循环流化床法、海水脱硫法、氨法、炉内喷钙尾部烟气增湿活化法、电子束法、烟气循环流化床法等十多种工艺的脱硫装置在商业化运行或进行了工业示范。特别是在大型锅炉领域如火力发电锅炉烟气脱硫主要以石灰石 / 石膏湿法脱硫技术为主。但是石灰石 / 石膏湿法脱硫技术普遍存在管道与脱硫塔内结垢、装置运行时液气比较大,增加了耗电量、脱硫装置占地较大、装置运行较为复杂、脱硫渣综合利用率低,处置困难等缺点。而湿式氨法脱硫工艺中由于存在排烟温度低(55℃左右)和氨逃逸的问题,从而导致烟气扩散性差、烟羽明显、装置容易腐蚀。 Contents of the invention [0004] 为了克服上述脱硫技术所存在的问题,为行业提供一种脱硫排放效果好、排烟温度高、运行经济、对装置无腐蚀且废水可循环利用的技术和装置,本发明提供了一种折流形蒸发式氨法脱硫技术和装置。 [0005] 本发明所采取的折流形蒸发式氨法脱硫技术方案是: [0006] 以氨水为脱硫剂,氨水通过锅炉排放的烟气预热到80-90℃,然后通过氨水蒸发器蒸发成汽态与烟气接触进行脱硫,脱硫后的烟气而后通过折流除雾器除雾后烟气改变方向由上至下进入脱硫吸附室,经脱硫环吸附脱硫,吸附脱硫后的烟气直接排放;在脱硫过程中,为了确保布风床和除雾器的清洁、畅通,布风床冲洗管和除雾器冲洗管每3-8个小时分别对它们进行冲洗。其装置主要包括折流形蒸发式氨法脱硫塔,该脱硫塔由底座、塔体、布风床、布风床冲洗管、氨水蒸发器、除雾器、除雾器冲洗管、脱硫环、烟气入口和烟气出口组成。 [0007...

AI Technical Summary

Problems solved by technology

However, limestone / gypsum wet desulfurization technology generally suffers from fouling in pipelines and desulfurization towers, large liquid-gas ratio during device operation, increased power consumption, large footprint of desulfurization devices, complex operation of devices, and low comprehensive utilization rate of desulfurization slag , disadvantages such as difficulty in handling

However, in the wet ammonia desulfurization process, due to the problems of low exhaust gas temperature (about 55°C) and ammonia escape, resulting in poor flue gas diffusivity, obvious smoke plume, and easy corrosion of the device

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