Pretreatment of super viscous oil wastewater and its application in refinery

Wastewater from super viscous oil processing cannot be effectively treated by conventional wastewater treatment plants in refineries because of its high concentration of various organic pollutants. In order to resolve this problem, a number of investigations were conducted in our work to understand the physicochemical properties, sedimentation, demulsification and pretreatment of such super viscous oil refinery wastewater. The results showed that the key issues for pretreatment of this wastewater were： （1） Optimized process parameters were used in the sedimentation and demulsification processes for oil removal to effectively recover oil and remove scum from wastewater; （2） A suitable flocculation process was selected to minimize oil, suspended solids （SS） and chemical oxygen demand （CODcr）. A pretreatment process including three continuous steps： oil removal by sedimentation, oil removal by demulsification, and flotation separation, was proposed and applied in Liaohe Petrochemical Company, PetroChina and the oil content in effluents was less than 200 mg/L and CODcr less than 2,500 mg/L, which completely met the requirement for influent of the conventional wastewater treatment plant, and the recovered super viscous oil reached 5,873 tons in the initial year in Liaohe Petrochemical Company, PetroChina.     

难生物降解炼油污水的“催化氧化+曝气生物滤池”处理技术研究

为解决炼油企业高浓度污水经"隔油+气浮+生化"的传统工艺处理时外排水难以稳定达标的问题,针对该类污水难生物降解的特点,采用"催化氧化+曝气生物滤池"组合处理工艺进行了中试研究。结果表明,利用·OH强氧化反应处理的污水经曝气生物滤池生化处理后,出水中COD、氨氮浓度、油浓度、悬浮物浓度的平均值分别为51.2,5.3,2.3,27 mg/L,COD降低率为83.1%,氨氮、油和悬浮物的平均去除率分别为80.1%,73.4%,61.6%,主要水质指标均达到国家一级排放标准。该技术不需改建炼油厂现有污水处理系统,可实现工业化应用。     

浅谈利用循环活性污泥法进行污水处理的自动控制系统设计

循环式活性污泥法是一种新型的污水生物处理工艺。以某化工厂的污水处理系统为例,阐述了利用循环活性污泥法处理工业废水时,自动控制系统的选型和设计原则。     

齐鲁乙烯污水场微砂沉淀工艺试验研究

通过实验室小试确定了微砂循环高效沉淀工艺处理齐鲁乙烯污水场废水中SS和总磷的试验加药条件:PAC加药量为80 mg/L、PAM加药量为5 mg/L。在该试验条件下,微砂循环高效沉淀池将齐鲁乙烯污水场出水SS含量自30~90 mg/L降至小于20 mg/L,将出水总磷含量由1~2 mg/L降至小于0.5 mg/L。     

电絮凝浮选法处理含油废水实验

在设制的电絮凝浮选法处理含油废水的实验工艺流程中，进行了不同电极、电流密度和电絮凝时间对除油效果影响的试验。确定适宜的实验参数后，对炼油厂含油废水进行了综合处理，结果油份去除率最高为９６％，悬浮物去除率最高为９７％，表明该法处理含油废水效果好。图３表３     

生物强化工艺处理乙烯碱渣废水中试研究

为了提高乙烯碱渣废水的处理效率,采用生物强化工艺在20 L/h试验装置进行了中间试验。结果表明:经过生物强化工艺处理后,乙烯碱渣废水化学需氧量、硫化物、石油类物质的平均去除率分别达到98.9%,99.9%,97.9%;废气达标率为100%,未产生二次污染。与焚烧、催化氧化工艺相比,生物强化工艺处理成本较低。     

N-环己基硫代邻苯二甲酰亚胺生产废水的物化特性及处理工艺

本文介绍了 N-环己基硫代邻苯二甲酰亚胺(CTP)生产过程中废水的物理化学特性,并提出了对各股废水分别预处理,然后对全厂废水进行厌氧/好氧综合处理。结果表明,该工艺处理 CTP 废水是成功的,处理后的废水达到 GB8978-1996《污水综合排放标准》中的二级标准。     

焦磷酸钠/二价铁络合物催化臭氧降解化纤污水

采用Fe²⁺配合物催化臭氧对化纤污水进行氧化降解,分别以乙二胺四乙酸(EDTA)、焦磷酸钠、柠檬酸钠为配合剂与Fe²⁺形成配合物进行筛选。采用正交试验法,以Fe²⁺浓度、初始pH值、气相臭氧浓度和水力停留时间(HRT)确定了氧化降解工艺条件,研究了降解化纤污水的氧化反应动力学参数。结果表明:Fe²⁺/焦磷酸钠配合物催化臭氧效果较好;最佳工艺条件为初始pH=7、Fe²⁺ 0.2 mmol/L、气相臭氧质量浓度25～30 mg/L、HRT 150 min,在此条件下,Fe²⁺/焦磷酸钠配合物催化臭氧对化纤污水COD去除率为72.4%;Fe²⁺焦磷酸钠配合物催化臭氧降解化纤污水为假一级动力学,反应速率常数为0.004 86～0.008 69 min^-1。     

Remediation of Oilfield Wastewater Produced From Alkaline/Surfactant/Polymer Flooding by Using a Combination of Coagulation and Bioaugmentation

In this study, performance of a full-scale combined treatment plant for oilfield wastewater from alkaline/surfactant/polymer flooding was investigated. The combined process consisted of chemical coagulation, hydrolysis/acidification, and bio-contact oxidation. The experimental results demonstrated that chemical coagulation treatment with polymeric ferric sulfate proved to be the most effective in removing the chemical oxygen demand (>80%) from the wastewater under the dosage of 600 mg/m³. The highest acidification efficiency in hydrolysis acidification tank was 25.8% at hydraulic retention time of 20 h. The average values of chemical oxygen demand, biochemical oxygen demand, oil, and NH₃-N of the combined process could be reduced to 116, 19, 4, 11, and 20 mg/L, respectively. The final effluent could meet the class II national wastewater discharge standard of petrochemical industry of China.     

二氧化氯催化氧化在处理钻井废水中的应用

〗针对钻井作业后期废水化学需氧量（COD_Cr）高的特点,在混凝法对钻井废水进行预处理的基础上,采用二氧化氯化学氧化和催化氧化分别进行二级处理。实验结果表明：对于实验所用钻井废水,二氧化氯催化氧化对COD_Cr去除效果优于二氧化氯化学氧化;溶液pH值为4,氧化剂投加量为400 mg/L,氧化反应时间为45 min,混凝-二氧化氯催化氧化组合法两步对COD_Cr总去除率达到97.4%。混凝-二氧化氯催化氧化工艺现场处理钻井废水,COD_Cr＜100 mg/L,达到了国家污水综合排放标准一级标准。二氧化氯催化氧化在处理钻井废水中具有很高的推广应用价值。     

低剂量水合物抑制剂对油田污水稳定性及环境影响的试验研究

低剂量水合物抑制剂是天然气开发中一种重要的化学品,随多相混输体系进入到油气水处理系统后,对油气水处理工艺和处理效果有着不同程度的影响。本文重点研究了5种不同类型的水合物抑制剂进入污水处理系统后对污水稳定性的影响,并初步探索了这几种水合物抑制剂对海洋环境的影响情况。研究表明不同类型的水合物抑制剂对油田污水的稳定性、污水中颗粒物粒径大小等有着不同程度的影响。进入污水处理系统的水合物抑制剂使污水的COD显著增加,直接排放易对环境造成污染,且很难采用一般的絮凝沉降方法去除,但因其具有良好的可生化性,可通过生化法进行处理。     

磷酸铵镁沉淀法与SBR工艺协同处理高含磷检修废水的研究

采用磷酸铵镁沉淀法和序列间歇式活性污泥法(SBR)协同处理高含磷检修废水,研究了磷酸铵镁反应中pH值、磷氮摩尔比、镁磷摩尔比等反应因素对高磷检修废水除磷效果的影响。结果表明,当反应中pH=9.5,n(Mg)∶n(P)∶n(N)=1.5∶1∶1时,高含磷检修废水总磷去除效果最佳,去除率可达到98%以上。采用该工艺对污水处理场高磷检修废水进行现场除磷预处理,总磷浓度由256 mg/L降至2.51 mg/L,总磷去除率达99%,效果显著。进一步SBR生化处理后,出水的pH值、COD、NH₃-N、TP和SS等各项指标均符合GB 8978—1996《废水综合排放标准》一级标准,达到了预期的处理目标。     

基于SnO2/Ti阳极的难生物降解有机物电催化氧化动力学

 通过理论推导得到填充型电化学反应器出水化学需氧量(COD)的预测模型，并通过处理DSD酸生产废水进行了验证。实验结果表明，反应过程中电压和电流的关系并不完全遵循欧姆定律，添加TiO₂和曝气下进行反应能够增强处理效果；较高的电压、较大的TiO₂添加量或高曝气强度均能获得较高的反应速率常数。利用该预测模型能够较为精确地预测DSD酸生产废水处理出水的COD值。     

80SS抗硫钢在高温高压环境中的H2S/CO2腐蚀行为

针对80SS抗硫钢的H_2S/CO_2腐蚀行为,在模拟油田H_2S/CO_2环境下,利用高压釜进行腐蚀试验,采用失重法测试了其腐蚀速率及咪唑啉型缓蚀剂的缓蚀效率,通过SEM、EDS和XRD测试手段,研究分析了腐蚀产物膜去除前后的形貌特征和化学组成。结果表明,80SS抗硫钢在H_2S/CO_2腐蚀环境中属于中等腐蚀,介质流动和CO_2/H_2S分压比值增大均可加速腐蚀,而缓蚀剂的加入可显著减小腐蚀速率;腐蚀类型存在点蚀或局部腐蚀特征,动态和高CO_2/H_2S分压比值时尤为严重;腐蚀产物膜主要成分为FeS,还含有少量其他成分。     

Treatment of drilling wastewater from a sulfonated mud system

Treatment of drilling wastewater from a sulfonated drilling mud system in the Shengli Oilfield, East China, was studied. The wastewater was deeply treated by a chemical coagulation-centrifugal separation-ozone catalytic oxidation combined process. The factors (i.e. pH value, chemical dosage, reaction time, etc.) influencing the treatment effect were investigated, and pH = 7 was determined as optimal for the coagulation; polymeric aluminum chloride (PAC) was selected as the optimal coagulant with a dosage of 18 g/L; cationic polyacrylamide (CPAM) with molecular weight of 8 million was selected as the optimal coagulant aid with an optimum dosage of 8 mg/L; and the optimal condition of catalytic ozonation was found to be a pH of 12 and an oxidation time of 40 min. The results showed that the combined treatment process was effective. The oil content and suspended solids content of the effluent reached the first class discharge standard according to China’s standard GB 8978-1996 (Integrated Wastewater Discharge Standard) and the chemical oxygen demand (COD) decreased to 195 mg/L from 2.34×10 4 mg/L after coagulation process and ozone oxidation at pH = 12 for 40 min.     

含氟废水治理技术研究进展

综述了近年来国内外对含氟废水处理方面的研究进展,介绍了沉淀法、吸附法、反渗透法、生化法、液膜法和电凝聚法的处理原理和研究进展,指出对含氟废水综合处理工艺开发值得研究。     

An alternative treatment process for upgrade of petroleum refinery wastewater using electrocoagulation

An electrocoagulation treatment process was developed for treatment and upgrade of petroleum refinery effluent （wastewater）, instead of the conventional methods, which can consume higher amounts of chemicals and produce larger amounts of sludge. The effect of the operation parameters, such as current density, initial pH, anode material, anode dissolution, energy consumption and electrolysis time, on treatment efficiency was investigated. The experimental results showed that the effluent can be effectively treated under optimal conditions. Fourier transform infrared （FTIR） analysis of the effluent, and scanning electron microscopy （SEM） coupled with energy dispersive analysis of X-rays （EDAX） of the sludge produced, revealed that the unwanted pollutants can be eliminated. The electrocoagulation treatment process was assessed by using the removal efficiency of chemical oxygen demand （COD）, total suspended solids （TSS）, and the general physicochemical characteristics of wastewater, and the results showed that the electrocoagulation is an efficient process for recycling of petroleum wastewater; it is faster and provides better quality of treated water than the conventional methods.     

橇装式钻井废水深度连续处理装置及其应用

为解决川渝气区钻井作业过程中废水处理达标难的问题,将化学混凝、絮凝、斜板快速分离、吸附氧化、超滤和反渗透等钻井废水处理技术工艺集成为橇装式一体化处理装置。该橇装式钻井废水深度连续处理装置各处理单元既可单独使用,又可有机结合;既可满足钻井后期高浓度废水处理,又可用于钻井前期低浓度废水处理,具有广泛适用性。装置已成功应用于龙岗10、龙岗29等10口井,共处理钻井废水达2×104 m3。应用效果表明,处理后水中的COD、SS、Oil等污染物指标可达到GB 8978—1996《污水综合排放标准》中一级标准值。结论认为,该装置的成功应用可提高川渝气区钻井作业废水污染防治水平,确保钻井作业清洁生产,达到节能减排目的,可实现环境效益、社会效益和经济效益的较好统一,也可用于陆上其他油气田钻井废水的处理。     

Study of an A/O Submerged Membrane Bioreactor for Oil Refinery Wastewater Treatment

Abstract

A 55-day experimental study was conducted to investigate the treatment process of oil refinery wastewater using submerged membrane bioreactor (MBR) technology. The results showed that the removal rates for chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD₅) were stable and averaged 92%. The average removal rates for NH₃-N, oil, and turbidity were shown to be 93.7%, 75.3%, and 94.6%, respectively. The removal rates for total phosphorus (TP), total suspended solids (TSS), suspended solids (SS), and phenol were shown to be greater than 98.5%, 97.9%, 93.8%, and 99.9%, respectively. This demonstrated that MBR technology had superior treatment effect on the above contaminants. During the 55-day operation, there was no trace of contamination on the membrane. This illustrated that the polyvinylidene fluoride (PVDF) flat sheet membrane manufactured by Toray Industries (Tokyo, Japan) had the ability to resist contamination.

     

胜利油田污水生化处理技术进展

为了减轻油田污水对环境的影响，充分利用污水资源，减少清水用量，胜利油田开展了油田污水生化处理技术研究和试验，同时配套其他工艺，对污水进行精细处理，实现低渗透油田污水的回注和油田污水达标外排。针对低渗透油藏回注污水难以达标的问题，应用生化处理配套精细过滤的污水精细处理工艺，在大芦湖油田樊41块进行了试验性的应用，处理后水质达到A1级标准。针对油田含聚污水难以处理的问题，应用生化处理技术降低污水化学耗氧量，处理后水质达到环保要求排放的标准。室内研究和现场试验结果表明，只要选用合适的微生物，油田污水可以进行生化处理。