热电厂循环冷却水系统水处理技术探讨

热电厂生产过程中冷却水消耗量很大,合理地对冷却水进行净化和回用意义重大.常规循环冷却水系统水处理技术有各自的使用范围和优点,但并不能较好地满足循环冷却水水质要求,且排污量较大、不能连续运行."旁流连续过滤-纳滤脱盐"技术,可连续排污排盐,并可自动调整排污量和排盐量,理论上可以克服常规循环冷却水系统水处理技术的缺陷.     

热电广循环冷却水系统水处理技术探讨

热电厂生产过程中冷却水消耗量很大,合理地对冷却水进行净化和回用意义重大。常规循环冷却水系统水处理技术有各自的使用范围和优点,但并不能较好地满足循环冷却水水质要求,且排污量较大、不能连续运行。"旁流连续过滤—纳滤脱盐"技术,可连续排污排盐,并可自动调整排污量和排盐量,理论上可以克服常规循环冷却水系统水处理技术的缺陷。     

NaOH在电厂循环排污水回用处理工程中的应用

因节水需要,河北某电厂回用水系统将原水由水库水改为循环排污水,因此需要对原工艺进行优化。因占地面积、成本等原因无法投建石灰处理系统,故将澄清池投药改为NaOH。对投加NaOH的运行效果、影响因素、经济性进行了分析讨论,实践证明投加NaOH能保证系统的稳定运行,出水水质满足回用要求。     

基于超滤—反渗透技术的核电站循环冷却排污水处理成本分析

针对我国面临的水资源严重短缺的问题,通过超滤—反渗透技术应用于核电站循环冷却排污水处理中成本模型的构建,以桃花江核电站为例,分析计算回用水价格,并与当地工业用水成本进行比较。结果表明,通过超滤—反渗透技术对循环冷却排污水进行处理并回用,经济适用性良好,可为解决我国内陆核电站水资源短缺问题提供参考。     

UF—RO在电厂循环排污水处理中的应用

火力发电厂循环排污水污染组分相对单一,而电厂用水水质层次较多,宜将循环排污水处理后回用,实现废水的零排放.以UF-RO为主体工艺处理某火力发电厂循环排污水,处理后出水水质优良,浓缩倍率有所提高,每年节水202.6万m3,节约资金18.74万元.     

反渗透工艺处理电厂循环冷却排污水

针对电厂循环冷却排污水浊度高 ,含盐量高的水质特点 ,采用反渗透工艺进行处理 ,出水含盐量小于 2 0mg/L ,满足锅炉预脱盐补充水的要求。介绍了反渗透工艺及其预处理工艺 ,并对该工艺处理成本和工程运行问题进行了分析     

水质变化对循环水系统排污水回用的影响及对策

针对循环水系统调整运行工艺后水质变化对排污水回用的影响进行了研究,认为水中Ca2+浓度的增加和总碱的降低是导致排污水回用装置出水硬度超标的主要原因,并提出了通过加入直接成垢因子的方法来去除水中的硬度。对三种软化方法的考察结果表明,对于永硬较高的循环水系统排污水,纯碱烧碱法的软化效果优于纯碱法和纯碱石灰法。在排污水中分别加入与其Ca2+和Mg2+浓度相同当量的纯碱和烧碱,可以使处理出水的Ca2+浓度和总硬度达到回用水的标准。反应时间对絮体的形成和沉降效果有一定影响,加药后的反应时间宜控制在30min以内。对于稳定运行的循环水系统,以固定的适当加药量进行投加,可获得良好的软化效果。     

循环水排污水回用试验研究

针对循环水排污水的特点,对回用预处理中可能出现的问题进行了分析.通过试验研究,提出了一些回用系统设计与运行方面值得注意的问题及其解决思路.     

超滤-反渗透工艺在处理循环水排污水中的应用

本文结合超滤-反渗透工艺处理循环水排污水的工程实例,对其系统调试、运行过程中出现的问题进行了静态和动态的实验分析,并提出了相应的处理建议,以推广超滤-反渗透水处理工艺在循环水排污水中的应用.     

反渗透技术处理燃煤电厂循环冷却水的试验研究

采用反渗透技术处理燃煤电厂循环冷却排污水,出水回用于循环冷却水的补充水.通过试验分析利用反渗透技术处理燃煤电厂循环冷却排污水的可行性,并确定反渗透系统的最佳工况.操作条件对反渗透膜的分离性能影响很大,膜的水通量随操作压力的增大、进水温度的升高而增加.产水盐浓度随操作压力的升高而降低,但随进水温度的升高而增大.试验最终确定适宜的操作压力为1.0MPa,进水温度为30℃,出水水质良好,经济和环境效益显著.     

连续微滤应用于印染废水反渗透预处理的研究

采用连续微滤(CMF)作为反渗透(RO)的预处理工艺,对印染废水二级生化出水进行深度处理。结果表明:CMF处理系统运行稳定,对色度、膜污染指数值的去除率均达到RO系统进水的要求。RO系统对盐度的去除率达到98%以上,出水水质优于自来水,各项水质指标满足印染工艺回用的要求。     

Integrated process control for recirculating cooling water treatment in the coal chemical industry

This work focused on the integrated process of the recirculating cooling water (RCW) treatment to achieve approximate zero emission in the coal chemical industry. The benefits of fractional and comprehensive RCW treatment were quantified and qualified by using a water and mass balance approach. Limits of cycle of concentrations and some encountered bottlenecks were used to ascertain set target limits for different water sources. Makeup water was mixed with water produced from reverse osmosis (RO) in the proportion of 6:4, which notably reduced salts discharge. Side infiltration, which settled down suspended solids, can reduce energy consumption by over 40%. An automated on-line monitoring organic phosphorus inhibitor feed maintains the RCW system stability in comparison to the manual feed. Two-step electrosorb technology (EST) instead of an acid feed can lead cycle of concentration of water to reach 7.0. The wastewater from RO, EST and filter was transferred into a concentration treatment system where metallic ions were adsorbed by permanent magnetic materials. Separation of water and salts was completed by using a magnetic disc separator. Applying the integrated process in a coal chemical industry, a benefit of 1.60 million Yuan annually in 2 years was gained and approximate zero emission was achieved. Moreover, both technical and economic feasibility were demonstrated in detail.     

集成膜技术工业废水深度处理回用试验研究

试验采用超滤+反渗透集成膜分离技术,目的是研究其集成工艺处理有色冶金工业废水的合理性和可行性。超滤试验主要测试了在不同水质情况下超滤膜的相关运行参数,主要测定指标有超滤系统的进水、产水和反冲洗水的水量,运行压力,出水浊度,SDI值等;反渗透试验主要测定指标有电导率,反渗透系统的进、出水量,运行压力等。试验研究表明:以预处理+超滤+反渗透组成的集成膜处理工艺,能够满足有色冶金工业废水处理回用的要求。     

黄河多泥沙水电站技术供水防淤设计

多泥沙水电站技术供水系统防淤有3种方式，最理想的是循环冷却供水。多泥沙中小型水电站技术供水系统应优先采用循环冷却供水。循环水池、循环冷却器和水泵是循环系统三要素，布置要合理，参数选择要留有裕量。重点介绍了循环冷却供水在技术供水系统中的重要性、应用和设计要点。     

Comparison of SAR (sodium adsorption ratio) between RO and NF processes for the reclamation of secondary effluent.

Secondary effluent reclamation and reuse has been considered as an alternative for agricultural irrigation water. Whilst all constituents in the reclaimed wastewater could affect plant growth and soil characteristics, the most important parameters for agricultural irrigation are salinity and SAR (Sodium Adsorption Ratio). Salinity affects the availability of crop water and sodium causes clay soils to disperse. Membrane technologies, especially NF (Nano-Filtration) and RO (Reverse Osmosis), have played in a key role reclaiming the secondary effluent. RO can remove monovalent and divalent cations simultaneously. However NF processes reject preferably divalent cations and most monovalent ions are allowed to pass through the NF membranes. This could make them have different SAR values for both NF and RO processes. Therefore the primary objective of this study is to examine if the SAR values of the reclaimed water could be changed while they undergo NF and RO processes. The measured SAR values of the secondary effluent, NF permeate, and RO permeate were 1.78, 4.67, and 0.72 respectively. The SAR value after NF (4.67) increased to more than twice that of the feed solution, whereas the SAR of the RO permeate decreased to 0.72. In general, the higher SAR the water has, the greater risk the soils have. Although the SAR value after NF was within the safe range, this increased SAR value will affect permeability of soil, thus limiting the reclaimed wastewater use for as agricultural irrigation water. Consequently, when the NF system is used for the reclamation of the secondary effluent, SAR has to be examined first because potentially it tends to increase the SAR value.     

Use of fouling resistant nanofiltration and reverse osmosis membranes for dyeing wastewater effluent treatment.

Dyeing wastewater was post-treated by using nanofiltration (NF) and reverse osmosis (RO) membranes. To reduce membrane fouling, poly (vinyl alcohol) (PVA) with a neutral charge was coated on NF and RO membranes. The effect of surface charge and surface roughness on membrane fouling was investigated. Dyeing wastewater was pre-treated by using coagulation, activated sludge process, and MF process to investigate the effect of the pre-treatment on the membrane fouling. It is demonstrated that the extent of fouling is significantly influenced by the surface roughness and the surface charge on the NF and RO membranes. A membrane with a smooth and neutral surface was fouled less. The pre-treatment was essential for avoiding NF and RO membranes fouling. The quality of the final permeate was acceptable for water reuse.     

Application of immersed MF (IMF) followed by reverse osmosis (RO) membrane for wastewater reclamation: A case study in Malaysia.

A pilot scale membrane plant was constructed and monitored in Shah Alam, Malaysia for municipal wastewater reclamation for industrial application purposes. The aim of this study was to verify its suitability under the local conditions and environmental constraints for secondary wastewater reclamation. Immersed-type crossflow microfiltration (IMF) was selected as the pretreatment step before reverse osmosis filtration. Secondary wastewater after chlorine contact tank was selected as feed water. The results indicated that the membrane system is capable of producing a filtrate meeting the requirements of both WHO drinking water standards and Malaysian Effluent Standard A. With the application of an automatic backwash process, IMF performed well in hydraulic performance with low fouling rate being achieved. The investigations showed also that chemical cleaning is still needed because of some irreversible fouling by microorganisms always remains. RO treatment with IMF pretreatment process was significantly applicable for wastewater reuse purposes and promised good hydraulic performance.     

Combined membrane bioreactor (MBR) and reverse osmosis (RO) system for thin-film transistor-liquid crystal display TFT-LCD, industrial wastewater recycling.

In TFT-LCD industry, water plays a variety of roles as a cleaning agent and reaction solvent. As good quality water is increasingly a scarce resource and wastewater treatment costs rises, the once-through use of industrial water is becoming uneconomical and environmentally unacceptable. Instead, recycling of TFT-LCD industrial wastewater is become more attractive from both an economic and environmental perspective. This research is mainly to explore the capacity of TFT-LCD industrial wastewater recycling by the process combined with membrane bioreactor and reverse osmosis processes. Over the whole experimental period, the MBR process achieved a satisfactory organic removal. The COD could be removed with an average of over 97.3%. For TOC and BOD5 items, the average removal efficiencies were 97.8 and 99.4% respectively. The stable effluent quality and satisfactory removal performance were ensured by the efficient interception performance of the UF membrane device incorporated with biological reactor. Moreover, the MBR effluent did not contain any suspended solids and the SDI value was under 3. After treatment of RO, excellent water quality of permeate were under 5 mg/l, 2.5 mg/l and 150 micros/cm for COD, TOC and conductivity respectively. The treated water can be recycled for the cooling tower make-up water or other purposes.     

硫酸生产废水治理与双水闭路循环系统的研究

利用石灰铁盐化学絮凝法对硫酸生产排放的酸性含砷废水进行治理,处理系统采用重力流,出口热水利用自然降温和高压离心风机的鼓风搅拌降温冷却,实现废水和冷却水的双水闭路循环再利用,达到节约水资源、保护水环境的目的。