合成洗涤剂生产废水的处理工艺设计

设计总说明

洗涤剂废水污染是指洗涤剂生产过程、日常生活洗涤及工业洗涤等未经处理而大量排入水体所造成的污染。洗涤剂中含有很高的含磷有机物，水体富营养化主要就是由于该类污染的存在，其中尤以洗涤剂工厂生产废水和日常生活废水对水体的污染严重。随着我国工业化和城市化进程的加快，洗涤剂污染废水的产生量在不断的增大，水体富营养化污染在不断的加重，已经严重的制约了我国经济社会的可持续性发展。当然随着我国科学技术的发展，已经建成有一大批城市污水处理厂来解决日常生活所产生该类污染，同时也从法律法规的程度来要求各洗涤剂生产工厂对其生产废水进行有效的处理。从而改善水质，减少其对环境的污染。

本次毕业设计的题目为3000m³/d合成洗涤剂生产废水的处理工艺设计，本次设计的主要任务是设计一套采用生物接触氧化池技术处理合成洗涤剂生产废水的工艺流程方案。生物接触氧化池法对洗涤剂废水的净化效果比较好，LAS的去除率可以达到90%以上。

本文在查阅了大量期刊、书籍等文献，对各种处理洗涤剂生产废水的方法进行了比较分析的基础上设计了生物接触氧化池法处理合成洗涤剂生产废水的工艺。对主要的处理单元的设计参数采用了合理的选择。对各主要单元的结构、平面布置和高程布置等进行了设计，并采用AutoCAD绘图工具来进行工程图纸的绘制。城市生活污水处理厂进水流量为：3000m3/d；进水水质为LAS：180mg/L；COD Cr：750mg/L；BOD5：190mg/L；SS：300mg/L；pH：10.8经处理后，出水水质达到了：LAS：10mg/L；COD Cr <200mg/；BOD5<95mg/L；SS<150mg/L；pH：6-9的出水标准。

该设计中的污水处理基本流程如下：

从废水管道进入废水处理厂的废水，pH很高，所以在经过格栅后必须先进入调节池进行pH的调节再进入初次沉淀池，在初次沉淀池中一部分沙粒等被去除同时加入混凝剂促进LAS的分离，隔油池是将LAS、油和部分有机物去除掉。再进入水解酸化池，对废水进行污泥混合及污染物的初次分解缓和后，进入生物接触氧化池。生物接触氧化池填料层中的生物膜，在底部供氧充足的条件下，对废水中的有机物等进行比较彻底的分解，污水得以净化，是整个处理流程的关键所在。处理的废水经过生物接触氧化池后进入二沉池，在二沉池内泥水分离，澄清后的废水经过清水池后排出系统。而经浓缩的污泥从沉淀池底部回流到水解酸化池中作为接种污泥。剩余污泥则在浓缩池中进行初步浓缩后干燥脱水，体积被大大的缩小后外运。

经处理工艺后的出水水质标准符合一般的废水排放标准，同时完全可以作为中水回用，对水环境的改善和减少工厂水质性缺水具有很好的促进作用。

关键词：合成洗涤剂生产废水；废水处理；生物接触氧化池

Design Instruction

Detergent wastewater pollution is refer to the water pollution that lead by the untreated water in the detergent production process, daily cleaning and industrial washing. Detergents contain very much phosphorus organic matters, water eutrophication is mainly caused by the existence of such pollution. And especially the waste water pulled by the detergent factory and daily life causes serious pollution of water bodies. As Chinese industrialization and urbanization process accelerated, the amount of detergent waste water continues to increase, water eutrophication in constant increase. It has been seriously restricted the development of Chinese economic and social sustainability. With the development of Chinese science and technology, while, our country has built a large number of urban sewage treatment plants to solve such pollution arising from daily life, and also some laws and regulations require the detergent factory an effective treatment of waste water. Then, the water quality has been improved and environmental pollution has been reduced.

My graduation project was titled 3000m³/d synthetic detergent wastewater treatment process design, this design's main task is to design a wastewater treatment process which has used the technology of biological contact oxidation pond to treat the synthetic detergent solution. Biological contact oxidation pond has a very good result in the purification of the detergent waste water, and LAS can be removed to 90%. For this paper I have skinned a wide range of journals, books and other literature and designed the biological contact oxidation pond to treat the waste water based on the comparative analysis of many methods to treat the wastewater caused by the production process of synthetic detergent. I have a reasonable choice to the design parameters of the main processing unit. And designed the major elements of the structure, layout and elevation design layout and used AutoCAD drawing tools to draw engineering drawings. Municipal sewage treatment plant influent flow rate: 3000m3/d, water quality for the LAS: 180mg/L, COD Cr: 750 mg/L, BOD5: 190 mg/L, SS: 300 mg/L, pH: 10.8 after treatment, water quality Reached LAS: 10 mg/L, COD Cr<200 mg/L, BOD5<95 mg/L, SS <150 mg/L, pH 6-9 effluent standards.

The basic design of the sewage treatment process is as follows:

Effluent from the waste pipe into the wastewater treatment plant has a high pH, so after enter through the grille, its pH must be adjusted in the adjustment tank and then enter into the primary sedimentation tank. Some sand was removed in the primary sedimentation tank and at the same time pulling coagulant into it to promote the separation of LAS, then LAS, oil and some organic can be removed in the part of grease traps .In the hydrolysis acidification tank, the effluent is mixed with sludge and pollutions are initial break. Then it eases into the biological contact oxidation pond. With the supply oxygen support, biofilm in the filler layer of biological contact oxidation tank can decompose the organic matters very well. Then the sewage can be purified. It is the key part of the whole process. Effluent and mud can be separated in the secondary sedimentation tank after the above process. The treated water finally discharged out of the system after entering into the clean water tank. And the concentrated sludge from the settling tank will be back to the hydrolysis acidification tank as a sludge seed. The other sludge will be concentrated and dehydrated.