【作者】 杨彦波；

【导师】 丁毅；

【作者基本信息】 陕西科技大学 ， 轻工技术与工程， 2012， 硕士

【摘要】 针对目前燃煤锅炉产生的二氧化硫造成日益严重的大气污染，在国家政策的干预下，各有关厂矿企业纷纷开始进行脱硫设备安装或改造。烟气脱硫过程工艺是过程工业的重要组成部分，属于环境和能源交叉领域，由于我国经济发展水平的限制，大气污染目前基本仍处于先污染后治理的状态。西安市环境保护局《关于进一步规范我市中小型燃煤锅炉烟气脱硫工程建设与管理工作的通知》就是政府部门对二氧化硫对环境污染的政策干预。烟气脱硫中采用的核心处理工艺大都是采用化学反应的手段，包括吸收、吸附、催化反应等。与通常的过程工艺一样，采用化学方法处理对象时，都可以概括的分为三个部分：1.原料的预处理，包括对处理对象的处理，如对燃煤锅炉烟气进行除尘、降温等。对添加的反应物的处理，如烟气脱硫中石灰石制粉等；2.化学反应，如石灰石与SO₂反应等；3.反应产物的后处理等。本文简要介绍了一些锅炉烟气脱硫方法，我国烟气脱硫技术应用现状，烟气脱硫技术存在的主要问题。湿法脱硫为目前使用范围最广的脱硫方法，占脱硫总量的90%以上。湿法脱硫根据脱硫吸收剂的原料不同又可分为石灰石/石灰法、氨法、钠钙双碱法、氧化镁法等，其中石灰石/石灰法、氨法、钠钙双碱法、氧化镁法使用较多。并结合陕西科技大学锅炉房实例，提出锅炉烟气脱硫处理技术方案。结合本项目实际情况，从工程投资、运行费用、二次污染、运营管理的难易以及多方面综合考虑，本方案设计采用钠钙双碱法。工艺流程为：来自锅炉的含尘烟气以15²2m/s的流速通过进出烟道进入筒体，含有[OH^-]离子的碱性水从脱硫塔中不同部位由螺旋喷嘴喷出，形成与烟气成逆向的多排高速雾化水雾，增加了烟尘硫氧化物与水的碰撞频率，并充分利用雾化液滴的速度造成很高的气液相对速度，以保证除尘和脱硫效果。同时气体上升增加了气液传质的表面积和湍流转台，提高了传质速率，二氧化硫与碱液发生气液交换，进一步提高了脱硫效果。脱硫生成物随水流到脱硫塔底部，从溢水孔排走，在筒体底部封底并设有水封曹以防烟气从底部泄露，备有清理孔便于进行筒体底部清理。脱硫后废水从底部溢流孔排除进入再生池，经过搅拌机与石灰浆液充分接触进行再生，随后自流进入沉淀池，在沉淀池固液分离，上清液自流进入澄清池，加钠碱再生后循环使用。沉入池底的固体经渣浆泵打入板框压滤机进行脱硫处理。这样不仅解决了脱硫渣的处理问题，同时减少了一次性投资，降低了运行成本。净化后的气体，通过筒体上部引出，从而达到预除尘脱硫目的，最后进入烟囱排入大气。更多还原

【Abstract】 In view of the current coal fired boiler sulfur dioxide produced causeincreasingly serious air pollution, in national policy intervention, the relevantfactories began to desulfurization equipment installation or renovation. Flue gasdesulfurization process is the important part of process industry, belonging toenvironmental and energy field, because our country economy development level,atmospheric pollution at present is still in the treatment after pollution status.Xi’an Municipal Environmental Protection Bureau" on further regulate our citymedium and small coal fired boiler flue gas desulfurization project constructionand management notice" is the government department of the sulfur dioxidepollution on environment policy intervention.Flue gas desulfurization by core processing technology mostly usedchemical reaction means, including absorption, adsorption, catalytic reaction.With the usual process, using chemical method to process objects, can besummarized into three parts:1. raw material pretreatment, including on theprocessed object processing, such as for coal-fired boiler flue gas dust, coolingand so on. To add a reactant, such as flue gas desulfurization of limestone milling;2.chemical reaction, such as limestone and SO₂reaction;3reaction products afterprocessing.This paper briefly introduces some methods of boiler flue gasdesulfurization, flue gas desulphurization technology in China the applicationpresent situation.Wet desulfurization is currently the most widely used methodof desulfurization desulfurization, accounted for more than90%of the total. Wetdesulfurization desulfurization absorbent materials according to different can bedivided again for limestone/lime method, ammonia, Na-Ca double alkalimethod, magnesium oxide method, in which the limestone/lime method,ammonia, Na-Ca double alkali method, magnesium oxide method to use more.,main problems existing in flue gas desulfurization technology. Combined withthe real examples of Shaanxi University of Science and Technology boiler, boiler flue gas desulfurization solution. Combined with the actual situation of theproject, from project investment, operating costs, two pollution, operation andmanagement of the difficult and many aspects considered, this design uses theNa-Ca double alkali method.Process for: From the boiler flue gas containing dust in15²2m/s flowrate through the import and flue gas into the cylinder, containing [OH^-] calledion alkaline water in different parts from the desulfurization tower by spiralnozzle, formation and flue gas into reverse multiple rows of high speed atomizedmist, smoke and sulfur oxides and water increasing the collision frequency, andmake full use of atomized droplet velocity caused by very high relative velocityof gas, to ensure that the dust removal and desulfurization effect. At the sametime gas increase the gas-liquid mass transfer surface area and turbulent turntable,improve the mass transfer rate, sulfur dioxide and alkali gas-liquid exchange,further improve the desulfurization effect. Desulfurization product with flow intothe desulfurizing tower bottom, from the overflow hole to drain away, in thebottom of the cylinder body and is provided with a seal cover to prevent leakageof flue gas from the bottom of Cao, with clearance hole for cylinder bottomcleaning.After the desulfurization waste water from the bottom of the overflow holeexcluded in the regeneration tank, through the mixer and a lime slurry fullcontact for regeneration, then flows into the sedimentation tank in sedimentationtank, solid-liquid separation, supernatant flow into the clarifier, plus sodiumalkali regeneration cycle. To sink to the bottom of the solid slurry into the plateand frame filter press is used for desulfurization. This not only solved theproblem of slag treatment, while reducing the amount of one-time investment,reduce operation cost. The purified gas, through the barrel upper extraction, so asto achieve the purpose of the dust removal and desulfurization, and finally intothe chimney into the atmosphere.更多还原