海上钻井平台高盐生活污水生物强化处理研究

发布时间：2019-03-25 09:00

【摘要】：随着我国经济的快速发展和海洋资源的大力开发,海洋环境的污染问题已被日益重视。根据国际海事组织(International Maritime Organization, IMO),从 1973 年开始对海上平台生活污水等排海水严格规定了排放限定值,主要考察污水中的BOD5(25mg/L),SS (35mg/L),大肠杆菌(100 个/100mL), COD (125mg/L),pH (6.0～8.5),余氯(2.5mg/L),TN (20mg/L)和 TP (1mg/L)。本课题以海上钻井平台高盐生活污水(3.5% NaCl盐度)为研究对象,以一体化MBR处理工艺为核心,考察了两种驯化方式的耐盐活性污泥系统,并对经筛选得到的四株高效嗜盐菌进行了鉴定,以及一体化污水处理装置对含盐生活污水的去除效能、膜污染机理和污泥产泥量研究。污泥驯化试验结果表明:逐级加盐自然驯化的活性污泥与稳定盐度投加嗜盐菌生物强化驯化的活性污泥相比,其系统恢复能力较强,但抗冲击负荷较差,不适用于高负荷的含盐废水处理。同时,以含盐分浓度较高的污泥作为接种污泥进行污泥驯化时,可以缩短耐盐活性污泥的驯化周期。菌群鉴定试验结果表明:筛选得到的四株嗜盐菌经过16S rDNA基因测序分析后,初步确定:菌株Y-1属于枝芽孢菌属(Virgibacillus sp.),菌株Y-2属于硝化杆菌属(Nitratireductor sp.),菌株Y-3属于节杆菌属(Arthrobacter sp.),菌株Y-4属于沙杆菌属(Arenibactersp.)。其中,菌株Y-1对有机物的去除效果最好,菌株Y-3对氨氮的去除效果最好。一体化污水处理装置运行结果表明:以逐级加盐自然驯化的活性污泥为接种污泥,在MLSS=9500 mg/L、HRT=22h、SRT=60d的条件下,一体化污水处理装置的COD平均去除率为90.9%,BOD5平均去除率为88.5%,TOC平均去除率为88.9%,NH4+-N平均去除率为60.4%,TP平均去除率为58.9%。膜污染与恢复试验结果表明:盐度、曝气量和膜通量(或HRT)等操作条件对膜污染影响较大,“浓差极化”是膜污染的主要类型,“清水清洗+酸洗(H2SO4) +碱洗(NaClO)”的清洗效果较好。
[Abstract]:With the rapid development of our country's economy and the exploitation of marine resources, the pollution of marine environment has been paid more and more attention. According to the International Maritime Organization (International Maritime Organization, IMO),) since 1973, the discharge limit of domestic sewage on offshore platforms has been strictly stipulated, mainly to investigate the BOD5 (25mg/L), SS (35mg/L) in the sewage. E. coli (100 / 100mL), COD (125mg/L), pH (6.0 / 8.5), residual chlorine (2.5mg/L), TN (20mg/L) and TP (1mg/L). Taking high salt domestic sewage (3.5% NaCl salinity) of offshore drilling platform as research object and integrated MBR treatment process as the core, two acclimatization methods of salt-tolerant activated sludge system were investigated in this paper. Four strains of highly effective halophilic bacteria were identified, and the removal efficiency, membrane fouling mechanism and sludge yield of the integrated sewage treatment unit for salty domestic sewage were studied. The results of sludge acclimation test showed that the natural acclimated activated sludge with step-by-step salt was better than the activated sludge acclimated with halophilic bacteria with stable salinity, but the resistance to shock load was poor. It is not suitable for high load salty wastewater treatment. At the same time, the acclimation period of salt-tolerant activated sludge can be shortened when the sludge with high salt concentration is used as inoculating sludge for acclimation. The results of microflora identification showed that after sequencing the 16s rDNA gene of the four selected halophilic bacteria, it was preliminarily confirmed that the strain Ya 1 belongs to the genus (Virgibacillus sp.), of Mycobacterium and belongs to the genus (Nitratireductor sp.), of nitrifying bacteria. Strain Y ~ (3) 3 belongs to Arthrobacter (Arthrobacter sp.), strain Y ~ (* 4) belongs to Salmonella (Arenibactersp.). Among them, strain Y ~ (3 +) had the best effect on removal of organic matter, and strain Y ~ (3 +) had the best effect on removal of ammonia-nitrogen. The operation results of the integrated sewage treatment unit show that the average removal rate of COD of the integrated sewage treatment unit is 90.9% under the condition of MLSS=9500 mg/L,HRT=22h,SRT=60d with the step-by-step salt acclimated activated sludge as the inoculating sludge and the average removal rate of COD of the integrated sewage treatment unit is 90.9%. The average removal rates of BOD5, NH _ 4-N and TP were 88.5%, 88.9%, 60.4% and 58.9%, respectively. The results of membrane fouling and recovery test showed that salinity, aeration volume and membrane flux (or HRT) had great influence on membrane fouling, and "concentration polarization" was the main type of membrane fouling. The cleaning effect of "clean water pickling (H2SO4) alkaline washing (NaClO)" is better.
【学位授予单位】：天津科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X799.3

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