改性淀粉絮凝剂处理含油废水的试验效果

通过将玉米淀粉与氢氧化钠、三氯化铝和无水碳酸钠在恒温磁力搅拌器上搅拌、加热,使得玉米淀粉改性,制得改性淀粉絮凝剂,并研究了改性淀粉絮凝剂对含油废水的处理效果.试验结果显示,在搅拌速度与时间分别为快搅速度200 r/min,快搅时间0.5 min;慢搅速度100 r/min,慢搅时间3 min的情况下,使用改性淀粉絮凝剂处理含油废水时,COD去除率为77.94%、石油类去除率为61.2%、透光率为62.7%、SS去除率为79.96%;最佳反应条件为:投药量为12 mg/L、温度为5~30℃、pH值为6-8.     

A review on application of flocculants in wastewater treatment

Flocculation is an essential phenomenon in industrial wastewater treatment. Inorganic coagulants (salts of multivalent metals) are being commonly used due to its low cost and ease of use. However, their application is constrained with low flocculating efficiency and the presence of residue metal concentration in the treated water. Organic polymeric flocculants are widely used nowadays due to its remarkable ability to flocculate efficiently with low dosage. However, its application is associated with lack of biodegradability and dispersion of monomers residue in water that may represent a health hazard. Therefore, biopolymers based flocculants have been attracting wide interest of researchers because they have the advantages of biodegradability and environmental friendly. But, natural flocculants are needed in large dosage due to its moderate flocculating efficiency and shorter shelf life. Thus, in order to combine the best properties of both, synthetic polymers are grafted onto the backbone of natural polymers to obtain tailor-made grafted flocculants. This paper gives an overview of the development of different types of flocculants that were being investigated for treatment of industrial wastewater. Furthermore, their flocculation performance will be reviewed and the flocculation mechanism will be discussed.     

不锈钢管制造业废水处理的工程实践

对不锈钢管业生产过程产生的废水采用中和、絮凝方法进行处理。出水可以达到国家污水综合排放标准（GB8978—1996）新建一级标准。利用该工艺处理废水的特点是工艺简单、投资省、占地小、操作简单、运行稳定、处理效果好。     

接枝淀粉高分子絮凝剂的合成及其应用

本文研究了Ｃｅ（Ⅳ）／ＨＮＯ３引发体系下，丙烯酰胺──淀粉接枝共聚合反应的影响因素及最佳工艺条件，由此得到的接枝淀粉接技效率达到９４．９％，支链分子量超过３００万．对多种工业污水絮凝处理结果表明，ＣＯＤｃｒ去除率、污泥沉降速度均不逊于聚丙烯酰胺３００万产品．     

What have we known so far about microplastics in drinking water treatment? A timely review

• 23 available research articles on MPs in drinking water treatment are reviewed. • The effects of treatment conditions and MP properties on MP removal are discussed. • DWTPs with more steps generally are more effective in removing MPs. • Smaller MPs (e.g.,<10 μm) are more challenging in drinking water treatment. Microplastics (MPs) have been widely detected in drinking water sources and tap water, raising the concern of the effectiveness of drinking water treatment plants (DWTPs) in protecting the public from exposure to MPs through drinking water. We collected and analyzed the available research articles up to August 2021 on MPs in drinking water treatment (DWT), including laboratory- and full-scale studies. This article summarizes the major MP compositions (materials, sizes, shapes, and concentrations) in drinking water sources, and critically reviews the removal efficiency and impacts of MPs in various drinking water treatment processes. The discussed drinking water treatment processes include coagulation-flocculation (CF), membrane filtration, sand filtration, and granular activated carbon (GAC) filtration. Current DWT processes that are purposed for particle removal are generally effective in reducing MPs in water. Various influential factors to MP removal are discussed, such as coagulant type and dose, MP material, shape and size, and water quality. It is anticipated that better MP removal can be achieved by optimizing the treatment conditions. Moreover, the article framed the major challenges and future research directions on MPs and nanoplastics (NPs) in DWT.     

混凝沉淀—气浮—生化处理洗毛废水

采用混凝沉淀－气浮－生化处理洗毛废水。混凝沉淀－气浮在进水ＣＯＤ１４５００ｍｇ／Ｌ,处理水量２０００ｍ＾３／ｄ,ＣＯＤ去除率９０％;ＨＲＴ ３２ｈ生化处理时,出水ＣＯＤ为１８７ｍｇ／ｌ,可达到污水综合排放二级标准（洗毛行业）。     

絮凝法处理含水溶性膦配体TPPTS废水

以Al-Fe混凝荆、聚丙烯酰胺（PAM）、十六烷基三甲基溴化铵（CTAB）为助凝剂,考察了水溶性膦配体间磺酸钠基三苯基膦（TPPTS）废水中化学耗氧量（COD）的去除率,以此来间接考察TPPTS的去除效果。结果表明,助凝剂的添加能提高COD的去除率。获得了化学耗氧量COD 1000～1500mg／L废水除膦的优化条件：pH=5．5,Al-Fe、CTAB、PAM的投加量分别为300mg／L、67mg／L和21mg／L时,COD去除率达92．9％。     

Synthesis and evaluation of cationic flocculant P(DAC-PAPTAC-AM) for flocculation of coal chemical wastewater

In this study, a high-efficiency cationic flocculant, P(DAC-MAPTAC-AM), was successfully prepared using UV-induced polymerization technology. The monomer Acrylamide (AM): Acryloxyethyl Trimethyl ammonium chloride (DAC): methacrylamido propyl trimethyl ammonium chloride (MAPTAC) ratio, monomer concentration, photoinitiator concentration, urea content, and cationic monomer DAC:MAPTAC ratio, light time, and power of high-pressure mercury lamp were studied. The characteristic groups, characteristic diffraction peaks, and characteristic proton peaks of P(DAC-MAPTAC-AM) were confirmed by fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), ¹H nuclear magnetic resonance spectrometer (¹H NMR), and scanning electron microscopy (SEM). The effects of dosage, pH value, and velocity gradient (G) value on the removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol by poly aluminum ferric chloride (PAFC), P(DAC-MAPTAC-AM), and PAFC/P(DAC-MAPTAC-AM) in the flocculation treatment of coal chemical wastewater were investigated. Results showed that the optimal conditions for the flocculation of coal chemical wastewater using P(DAC-MAPTAC-AM) alone are as follows: dosage of 8–12 mg/L, G value of 100–250 s ^? 1, and pH value of 4–8. The optimal dosage of PAFC is 90–150 mg/L with a pH of 2–12. The optimal dosage for PAFC/P(DAC-MAPTAC-AM) is as follows: PAFC dosage of 90–150 mg/L, P(DAC-MAPTAC-AM) dosage of 8–12 mg/L, and pH range of 2–6. When P(DAC-MAPTAC-AM) was used alone, the optimal removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol were 81.0%, 35.0%, 75.0%, and 80.3%, respectively. PAFC has good tolerance to wastewater pH and good pH buffering. Thus, the flocculation treatment of coal chemical wastewater using the PAFC/P(DAC-MAPTAC-AM) compound also exhibits excellent resistance and buffering capacity.     

Acceleration of floc-water separation and floc reduction with magnetic nanoparticles during demulsification of complex waste cutting emulsions

Waste cutting emulsions are difficult to treat efficiently owing to their complex composition and stable emulsified structure.As an important treatment method for emulsions,chemical demulsification is faced with challenges such as low flocs-water separation rates and high sludge production.Hence,in this study,Fe₃O₄ magnetic nanoparticles(MNPs)were used to enhance chemical demulsification performance for treating waste cutting emulsions under a magnetic field.The addition of...     

高效氧化偶合絮凝法强化处理受污染湖水的研究

为了研究高效氯化偶合絮凝剂对有机物含量较高原水的应用效果．进行了氧化偶合絮凝法强化处理受污染湖水的试验研究．并对其作用机理进行了初步探讨。结果表明．高效氧化偶合絮凝法对COD，SS，NH3^-N和TP均有良好的去除效果．在最佳条件下,去除率分别高达85％、95％、87％和96％．出水COD，SS，NH3^-N和TP的平均浓度分别为5.8、1.4、1.6和0.9mg／L。作用机理分析表明．氯化偶合絮凝剂在处理过程中充分利用氧化絮凝协同作用．对胶体性物质和溶解性物质均有较好去除效果。