炼化企业碱渣处理技术进展  

PROGRESS OF TREATMENT TECHNOLOGY OF CAUSTIC SLUDGE FROM REFINERY OR ETHYLENE PLANT

作　　者：刘忠生[1] 赵磊[1] 刘志禹 王海波[1] 王新[1] Liu Zhongsheng;Zhao Lei;Liu Zhiyu;Wang Haibo;Wang Xin(SINOPEC Dalian(Fushun)Petrochemical Research Institute,Dalian,Liaoning 116045)

机构地区：[1]中国石化大连(抚顺)石油化工研究院

出　　处：《石油炼制与化工》2019年第10期108-114,共7页Petroleum Processing and Petrochemicals

基　　金：中国石油化工股份有限公司合同项目(315054)

摘　　要：炼化企业碱渣碱度大,化学耗氧量(COD)、硫化物和盐浓度高,含大量难微生物降解有机物,宜先预处理再进污水处理场。中和酸化作为简单传统的预处理方法,投资小、操作费用低,可脱除硫化物和难微生物降解的有机物,但COD仍然很高,且产生大量恶臭气体。在中和酸化基础上增加萃取或生物曝气预处理,可提高COD去除率,但仍未解决好恶臭污染问题。缓和湿式氧化-SBR预处理出水可全部进污水处理场达标处理,解决了碱渣中和过程的恶臭污染问题,但其氧化尾气有少量异味和挥发性有机物(VOCs)排放,且投资和操作费用较高。中和酸化硫回收及气水净化技术可依托厂内现有污水处理场、硫回收系统、VOCs废气处理装置,通过新建碱渣中和酸化氮气吹脱反应沉降器、吹脱气H 2S吸收塔,以较低的投资和操作费用,实现碱渣废水的达标处理、中和酸化释放气中的H 2S和VOCs的回收、以及尾气的高标准净化达标排放。Caustic sludge generated from refinery and ethylene plant is considered as waste which contains excessive amount of alkaline,COD,sulfide,salt and nonbiodegradable organic compounds.It is suitable to be pretreated first and then into the sewage treatment field.Sulfuric acid neutralization-acidification is a simple and traditional pretreatment method with low investment and operating cost,which can remove sulfide and several organic matters.However COD is still high and a large amount of malodorous gases is produced in the neutralization process.Increasing the extraction or biological aeration pretreatment on the basis of neutralization acidification can improve the COD removal rate,but still does not solve the problem of odor pollution.Wet air oxidation-SBR(sequencing batch reactor activated sludge process)pretreatment method has solved the odor pollution problem in caustic sludge neutralization process.All the pretreated caustic sludge can be treated in the sewage treatment field,but the oxidized tail gas has a small amount of odor and VOCs emissions,and its investment and operating cost is higher.Caustic sludge neutralization-acidification sulfur recovery and gas water purification technology is depended on the existing sewage treatment field in the factory,MDEA hydrogen sulfide recovery system,and VOCs exhaust gas treatment device.Through the newly established caustic sludge neutralization-acidification and nitrogen blowing reaction precipitator and blowing off hydrogen sulfide absorption tower,several goals can be achieved with relatively lower investment and operating cost,such as treated neutralized wastewater to meet discharge standards,hydrogen sulfide and VOCs recovery,high level purification of exhaust gas to meet the standard emissions.

关 键 词：炼化企业 碱渣 中和 酸化 恶臭 硫回收 生化 脱盐 

分 类 号：X70[环境科学与工程—环境工程]