中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
中水回用于循环冷却水集成技术研究

文献类型:学位论文

作者王岽
学位类别博士
答辩日期2015-05
授予单位中国科学院研究生院
授予地点北京
导师栾兆坤 ; 王军
关键词中水回用,循环冷却水,腐蚀,磷酸盐,羟基羧酸盐,reclaimed water reuse, recirculating cooling water, corrosion inhibition, phosphate, hydroxyl carboxylate
其他题名Study on an Integrated Process of Reclaimed Water Reuse to Recirculating Cooling Water System
学位专业环境工程
中文摘要     中水回用是解决水资源短缺的重要途径。近年来,对中水在工业企业中大规模应用可行性的研究已得到水处理领域研究者越来越多的关注。以开发经济适用、环境友好和安全稳定的城市中水回用于石化企业循环冷却水集成技术为目标,通过对城市中水水质特性、中水输送管道腐蚀控制、新型无磷缓蚀剂的效果及机理、中水回用于循环冷却水处理等方面的研究,提出了中水输送管道和下游循环冷却水系统腐蚀综合控制方案。主要研究结果如下:
(1) 研究了中水中侵蚀性离子和有机污染物对其腐蚀性的影响规律,并与几种腐蚀结垢平衡指数的计算结果进行了比较。结果表明,通过实际测试掌握中水水质特性是成功实现中水回用于循环冷却水的关键步骤。
(2) 以新鲜水输送管道的腐蚀速率为评价指标,考察了中水中原有磷酸盐、外加锌盐和补充含磷缓蚀剂2-羟基亚乙基二膦酸(HEDP)对输送管道的腐蚀控制效果。结果表明,以单独的磷酸盐作缓蚀剂,不能满足中水输送管道的缓蚀要求;在外加锌盐0.5 mg/L 的条件下,达到缓蚀指标的磷酸盐临界浓度为1.7 mg/L;当中水中原有磷酸盐不足1.7 mg/L 时,可补充适量的HEDP 使水中的总磷酸盐含量达到1.7 mg/L,也可以获得满意的缓蚀效果。
(3) 在小试实验基础上,以中水中的磷酸盐(5 mg/L)和酒石酸钠(10 mg/L)为缓蚀主剂,分别开发了适用于以中水为补充水的高浓缩倍数循环冷却水系统的含磷复合配方RWP-1 和无磷复合配方RWNP-1。除了分散剂LN-104B(10 mg/L)和缓蚀助剂锌盐(2 mg/L),含磷和无磷复合配方还分别采用2-膦基丁烷-1,2,4-三羧酸(PBTCA)(6 mg/L)和聚环氧琥珀酸(PESA)(6 mg/L)作为阻垢剂,以获得最佳的缓蚀阻垢效果。对复合配方性能的动态模拟实验验证结果表明,系统的腐蚀速率和粘附速率均达到中国石化标准,其效果显著优于国内现用的循环冷却水处理药剂产品。
(4) 针对中水输送管道和下游循环冷却水系统的腐蚀问题,提出了腐蚀控制整体运行方案。在污水处理厂或中水生产装置出水口,向水中加入0.5 mg/L 的锌盐缓蚀剂;当中水中原有的磷酸盐含量小于1.7 mg/L 时,补充HEDP 至总磷酸盐含量达到1.7 mg/L 或补充1.0~2.0 mg/L 的酒石酸钠可抑制中水输送管道的腐蚀;中水进入循环冷却水系统后,不需要再投加缓蚀剂。利用中水中原有磷酸盐作为缓蚀剂的水处理方案,不仅可以节约宝贵的水资源和磷资源,降低水处理成本,收到可观的经济效益;而且还能够减少磷排放,降低环境水体富营养化的风险。
(5) 通过电化学和表面分析的方法,对羟基羧酸盐在碳钢表面形成缓蚀膜的机理进行了研究。动电位极化曲线(PDPC)和交流阻抗(EIS)测试结果表明,葡萄糖酸盐、柠檬酸盐和酒石酸盐均为阳极型缓蚀剂,它们对碳钢的缓蚀作用排序为:酒石酸盐>葡萄糖酸盐>柠檬酸盐。X 射线光电子能谱(XPS)分析结果表明,缓蚀膜是由以FeOOH、α-Fe2O3 等为主的铁氧化物及羟基羧酸盐和碳酸钙共同形成的复杂混合物。对碳钢表面缓蚀膜形貌的宏观观察和扫描电子显微镜(SEM)观察均支持上述结论。
英文摘要    Reclaimed water reuse is an important solution for dealing with the issues of water resources shortage. It has been gained increasing attention by the researchers in the field of water treatment on the feasibility of widely applying reclaimed waters into industries in recent years. For the sake of developing an integrated process for economically, environmentally friendly and safely using municipal reclaimed water to the recirculating cooling water systems (RCWSs) in petrochemical industries, the characteristics of reclaimed water, the corrosion inhibition in the pipeline of reclaimed water supply (PRWS), the efficiency and the mechanism of novel non-phosphorous corrosion inhibitors and the treatment of the RCWS made up by the reclaimed water were investigated, and a comprehensive strategy for the corrosion inhibition of RCWS and PRWS was proposed. The main results are as follows:
    (1) The corrosive principles of the aggressive anions and organic contaminants in the reclaimed water were studied and a comparison was made between the experimental results and the corrosin-scaling balance indexes. They suggest that to well know the specialties of the water by determination and analysis is a key step to use reclaimed water to RCWS successfully.
(2) Based on the evaluation criterion of the corrosion rate in the pipeline of fresh water supply, the corrosion inhibitions of the phosphate alone in the reclaimed water, the zinc salt additive and a phosphorous corrosion inhibitor of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) were tested. The results show that the corrosion inhibition can not be satisfied by phosphate alone even extra phosphate was dosed. With the aid of zinc salt of 0.5 mg/L, a critical dosage of phosphate of 1.7 mg/L was achieved to meet the need of corrosion inhibition, which can also be desired by dosing HEDP to a total phosphorus content of 1.7 mg/L as the phosphate in the reclaimed water is not adequate.
 (3) Based on the bench-scale experimental results, a phosphorous program of RWP-1 and a non-phosphorous program of RWNP-1 were developed for the treatment of a highly concentrated RCWS made up by reclaimed water. The phosphate in the reclaimed water (5 mg/L) and sodium taratrate (10 mg/L) were used as the main corrosion inhibitors in these two programs, respectively, which also consist of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) (6 mg/L) or polyepoxysuccinic acid (PESA) (6 mg/L) as scale inhibitors besides a copolymer dispersant of LN-104B (10 mg/L) and a corrosion inhibition additive of zinc salt (2 mg/L). The pilot-scale experimental results show that the corrosion rate and the adhension rate both meet the regulation of cooling water treatment of SINOPEC, suggesting that the two programs have much better performances than the chemical programs for recirculating cooling water treatment currently used in China.
(4) A combined operation scheme for the corrosion inhibition either in PRWS or in downstream RWCS was proposed. A zinc salt of 0.5mg/L was dosed before the reclaimed water was transported in PRWS. At the phosphate concentration of below 1.7 mg/L, HEDP was supplied to a total phosphorus content of 1.7 mg/L, or sodium tartrate of 1.0-2.0 mg/L was used for the corrosion inhibition in PRWS. No corrosion inhibitors then was desired for the treatment of downstream RWCS. As a result, not only fresh water resouce, phosphorus resource and the cost of water treatment can be saved, but also the emission of phosphorus can be reduced. The risk of eutrophication in the environmental waters therefore will be lowered.
(5) The mechanisms of the formation of corrosion inhibition film on the carbon steel surface induced by hydroxyl carboxylates were investigated by means of electrochemistry and surface analysis. The results of potentiodynamic polarization curve (PDPC) and electrochemical impedance spectroscopy (EIS) show that gluconate,citrate and tartrate are all anodic type corrosion inhibitors and the sequence of their inhibitive performances is tartrate > gluconate > citrate. The results of X-ray photoelectron spectroscopy (XPS) reveal that the corrosion inhibition films consist of iron oxides mainly including FeOOH and α-Fe2O3, hydroxyl carboxylates and CaCO3.The above-mentioned conclusions are also confirmed by macroscopical observation and the observation of scanning electron microscope (SEM).
源URL[http://ir.rcees.ac.cn/handle/311016/34380]  
专题生态环境研究中心_环境水质学国家重点实验室
推荐引用方式
GB/T 7714
王岽. 中水回用于循环冷却水集成技术研究[D]. 北京. 中国科学院研究生院. 2015.

入库方式: OAI收割

来源:生态环境研究中心

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