工业废水零排放中的浓盐水处理技术

在工业零排放环节中最为关键的一个环节就是对浓盐水的处理,由于在工业废水脱盐流程中必然会排出大量的浓盐水,因其中含有无机盐、重金属、化学制剂等大量毒害物质,为此必须要对浓盐水进行全面、有效的处理,继而确保工业废水真正地实现零排放。本文主要对浓盐水零排放处理技术进行了深入的分析,继而为相关领域的研究提供更有价值的参考依据。     

梅钢公司浓盐水深度处理应用研究

介绍了梅钢公司冷轧脱盐水系统浓水的处理回用研究,对双膜法浓水处理工艺路线与传统处理方法进行了分析、比较。详细介绍了双膜法处理工艺在梅钢冷轧脱盐水站的应用。强调了双膜法浓水处理工艺在节水、减排方面的作用。     

浅谈海水淡化浓盐水的影响及利用

简要介绍海水淡化的各种处理方式,对海水淡化产生的浓盐水对海洋环境的影响进行详细讨论,对国内开展的浓盐水综合利用进行分析,提出加快浓盐水回用的建议。     

石墨废水双极膜电渗析制酸、碱工艺探讨

石墨废水氯化钠的含量为4％左右,硝酸盐1870mg/L,饱和碳酸钠及20ppm左右的氟离子,pH值11～12.本工艺采用均相膜电渗析工艺对石墨废水进行浓缩,采用3隔室双极膜工艺将浓缩转化为酸碱,本工艺能将石墨废水的氯化钠转化为8％的氢氧化钠和7.3％的盐酸.运行电渗析能耗为14.3kWh/t,双极膜处理浓盐水能耗为183.96kWh/t,碱净能耗为2186kWh/t(不含水泵).     

高浓含盐有机废水资源化处理方法探讨

高浓含盐有机废水目前产量大、来源广、化学成分复杂,且有一定的危害性,关于其有效处理特别是资源化处理再利用的探讨也不断深入,目前取得了一定的进展,一些新技术在高浓含盐有机废水资源化处理中发挥了实效.要想提升资源化处理效果,必须基于综合化处理的思维做好不同成分的处理.因此就高浓含盐有机废水资源化处理进行综合探讨,以分别实现...     

节水新技术在长庆石化公司的应用

长庆石化先后建设两套70m3/h初级再生水深度处理回用装置、一套60m3/h反渗透浓水回用装置和一套80m3/h凝结水除油除铁装置,采用的超滤、反渗透、陶瓷超滤等新技术,具有装置分离效果好、占地面积小、操作简单、安全环保等优点,应用"超滤+反渗透"双膜系统,其污水水质逐步改善,浊度明显下降,由过去的平均25NTU,下降为8NTU,实现了废水回用,有利于循环水系统的长周期运行,特别在减少换热设备腐蚀和黏泥生成,延长换热设备寿命、提高换热效率上有突出作用;浓水反渗透及二级除盐水系统的建立,实现了废水高等级回用,在同等工况下,2008年与2007年相比,除盐水消耗量平均减少1663t/d;应用无机陶瓷滤膜技术,又在实现废水高等级回用的同时,将其热能一并回收利用,真正达到高水高用的目的。几套装置合计投资为991万元,新增收益合计为680.2万元,投资收益比为0.69,投资回收期在2a以内。应用上述工艺处理后的废水,分别用作循环水系统、空冷装置和工业锅炉的补充水,吨油耗水从2002年的1.08t/t,下降为2010年的0.58t/t。     

降膜蒸发—凝结型闭式循环太阳能蒸馏系统的模拟实验研究

建立了一套采光面积为1．07m∧2、主动回收蒸汽潜热及浓海不余热降膜蒸发－凝结型闭式循环太阳能蒸馏系统,4盏卤素灯作为太阳能模拟器，对该系统进行了模拟实验研究。实验结果表明，由于在本蒸馏系统中采用了强迫降膜蒸发及降膜凝结技术，使其中大部分的蒸汽潜热以及浓盐水的显热都得到了重复利用，单位采光面积的产量相对于传统的盘式（单级）太阳能蒸馏器提高了2－3倍。     

热电厂“含氨”蒸汽作为生活用汽对人体无害

随着热电厂大容量、高蒸汽参数热力设备的使用和热电联产技术的推广应用,对水提出了高纯度、大流量的要求。化学除盐水处理工艺已越来越多地被广大热电厂所设计采用。调节给水pH值的方法,有氨处理、胺处理和给水中性水规范等。目前,采用较普遍的方法是在水中加氨水,通常称为加氨处理。实践证明,加氨处理能够减轻除盐水对热力系统中     

正渗透海水淡化联合多效蒸发制盐系统的研究

正渗透海水淡化作为一种新的膜分离技术以其能源消耗低、产水率高等优点被广泛关注,相较于传统的制盐方式周期长,产量低,效率差等问题制约着企业的发展,正渗透海水淡化技术获得淡水的同时,可以从浓盐水中提取出工业用化工用品,从而给企业带来巨大的经济收益。本文介绍海水淡化结合制盐系统的工艺流程。     

盐差能发电技术的研究进展

盐差能是一种新型的可再生的海洋能,主要存在于河流入海口处。目前提取盐差能主要有3种方法:渗透压能法(PRO)——利用淡水与盐水之间的渗透压力差为动力,推动水轮机发电;反电渗析法(RED)——用阴阳离子渗透膜将浓、淡盐水隔开,利用阴阳离子的定向渗透在整个溶液中产生的电流;蒸汽压能法(VPD)——利用淡水与盐水之间蒸汽压差为动力,推动风扇发电。渗透压能法和反电渗析法有很好的发展前景,目前面临的主要问题是设备投资成本高,装置能效低。蒸汽压能法装置太过庞大、昂贵,这种方法还停留在研究阶段。     

The Bad Blumau geothermal project: a low temperature, sustainable and environmentally benign power plant

The 250 kW geothermal project at Bad Blumau is the first geothermal project developed in Austria by the private sector following the deregulation of the electricity industry in this country. What makes the project unique besides its private ownership structure is its ability to generate electrical power and district heating for the Rogner Bad Blumau Hotel & Spa by using a low temperature geothermal resource. Installed in the record time of less than a week, the air-cooled ORMAT ® Energy Converter (OEC) CHP module has been in commercial operation since July 2001. With an annual availability exceeding 99%, between October 2001 and December 2002 the plant delivered 1,560,000 kWh to the local grid. The geothermal CHP module utilizes brine at 110 °C, available from a 3000 m deep production well. Exiting the OEC unit at a temperature of 85 °C, the brine is then fed into the district heating system, providing heat for the Rogner Bad Blumau Hotel & Spa. The geothermal brine is returned from the district heating system and injected into a 3000 m depth reinjection well. The system is a pollution-free, unattended operating power generation module, which has avoided more than 1100 kg of CO₂ emissions over its first operating year.     

Discrepancies in brine density databases at geothermal conditions

The study is aimed at evaluating the influence of brine density data on the assessment of pumping requirements for geothermal installations. Five databases were compiled and compared, based on an evaluation of buoyancy effect in a producing well at the site of the Soultz-sous-Forêts EGS/HDR project. The results show large discrepancies between the different references, which lead to severe inaccuracies in the evaluation of the buoyancy effect, and thus of the pumping requirements. It is therefore recommended that care be taken when using such databases, in particular when determining the size of the pumping systems. It is also recommended that new measurements of brine densities be carried out, focussing specifically on geothermal conditions.     

The potential of the use of dense fluids for initiating hydraulic stimulation

To improve preferentially the permeability of fractures in the deepest parts of a geothermal reservoir, a dense fluid may be injected during the very first phase of a hydraulic stimulation test. To initiate such a permeability-enhancement process in the 5000 m deep reservoir of the European Enhanced Geothermal System (EGS) project at Soultz-sous-Forêts, France, a concentrated NaCl brine was injected. The effects of this injection were estimated using measured hydraulic and microseismic data. Two tasks associated with hydraulic stimulation have been shown to be important for this purpose: (1) determination of the failure pressures of the various fractures intersecting the open-hole section under stimulation, and (2) calculation of the transient hydraulic pressure profile in the borehole.Using the numerical borehole code HEX-B, the transient pressure profiles during stimulation of wells GPK2 (June 2000) and GPK3 (May 2003) were calculated on the basis of measured wellhead data. A comparison of the temporal history of near-borehole microseismic events during the GPK2 test and downhole pressure development in the open-hole sections of this borehole indicated that use of a dense brine helped stimulate the bottom part of this well. The corresponding analysis for the GPK3 test showed that the failure pressure of the fractures in the bottom part of the wellbore was never exceeded when injecting the dense brine. We can, therefore, assume that the brine had no effect on the fractures in GPK3.     

利用太阳能制取海盐传热过程的试验分析

测试了盐田卤水、土壤和环境芭及同期太阳辐照度等数据，计算了卤未与土壤间的导热，卤水以空的辐射换热和卤水对环境的对流换热，并分析了它们对卤水蒸发速率的影响。结果表明，卤水与土壤间采取良好的隔热措施，抑制卤水对土壤的传热，可将卤 水的蒸发速率近１０％。同时进行了试验验证。     

“Energy Tower” combined with pumped storage and desalination: Optimal design and analysis

The “Energy Tower” (ET) is a power plant project which uses hot dry air and seawater to produce electricity. An optimized design of a system that is a combination of an ET, pumped storage and seawater desalination plant is considered. A model set covering each subsystem, and results of the optimized design for a project in the area of Eilat are presented. The additional benefit from combining the systems comes from an efficient use of the energy in the brine water coming from the desalination process, and from using pumped storage in an unconventional way. The benefits of the combined system lead to an increase of 14% in the annual net profit, compared to the sum of profits from optimally designed stand-alone systems.     

On the verification of the effect of water depth on the performance of basin type solar stills

Many experimental and numerical studies have been done on different configurations of solar stills to optimize the design by examining the effect of climatic, operational and design parameters on its performance. The majority of the investigators presented their results in scatter diagrams rather than correlations. One of the most important of the operational parameters that has received a considerable attention in the literature is the brine depth. A good number of the investigations on the effect of brine depth are cited in this study. For each of these studies, a correlation was developed from the data reported by each study. A concluding correlation from all brine depth data was developed. The correlation showed a decreasing trend in the productivity with the increase in the brine depth. An experimental study was subsequently conducted to verify this trend by an experimental investigation on a solar still that was constructed and tested with five different brine depths, namely 1, 4, 6, 8 and 10 cm. The present study validated the decreasing trend in productivity with the increase of brine depth and showed that the still productivity could be influenced by the brine depth by up to 48%.     

Chemistry of silica in Cerro Prieto brines

We have studied the precipitation of amorphous silica from synthetic geothermal brines that resemble the flashed brine at Cerro Prieto. We found that part of the dissolved silica quickly polymerizes to form suspended colloidal silica. The colloidal silica flocculates and settles slowly at unmodified brine pH values near 7.35. Raising the pH of the brine to about 7.8 by adding base and stirring for a few minutes causes rapid and complete flocculation and settling. These results have been confirmed in the field using actual Cerro Prieto brine. Several commercially available flocculating agents were also tested. Both in the laboratory and in the field, we found quaternary amines to be effective with some brine compositions but not with others.These results suggest the following simple preinjection brine treatment process: age the brine for 10 – 20 min in a covered holding tank, add 30 to 40 ppm lime (Ca(OH)₂), stir for 5 min, and separate the flocculated silica from the brine using a conventional clarifier. The brine coming out of such a process will be almost completely free of suspended solids.The pilot plant tests needed to reduce this conceptual process to practice are discussed.In a separate study, we researched the rate of deposition of silica scale from synthetic brines. We found that a modest decrease in pH could significantly reduce the scaling rate at a reasonable cost.     

A simplified mathematical model for predicting the nocturnal output of a solar still

The production capacity of a solar still which converts saline water to fresh water can be increased by introducing hot feed water into the unit at night. A waste heat source, such as cooling water from a power plant, can be used to preheat the feed. The nocturnal production, i.e. the distilled water produced at night, seems to be influenced by several parameters. However, a simplified mathematical model suggests that the distillate depends only on the initial brine temperature, the drop in brine temperature and the brine depth. This was experimentally verified for different brine depths and for initial brine temperatures up to 150°F.     

A brine mixing mobile unit in oil and gas industry—An example of a cost-effective,efficient, and environmentally justified technical solution

The present work shows the technical solution for a mobile unit used for brine mixing in oil and gas industry. Brine is widely used as a fluid when servicing oil and gas wells and pipelines. The use of brine in the process of pipeline overhaul allows safe operation of clogged parts of petroleum wells. In this study, we suggest a technical solution for automated production, storage, and shipping of mentioned brine. The process, methodology, equipment, and implemented “touch panel” application are innovative because they allow cost-effective, efficient, and environmentally safe preparation of brine. The primary goal of the research is to illustrate the use of the mobile unit, as well as innovative importance and usefulness of the process of mixing brine. Furthermore, its aim is to highlight the critical points and possible improvements of described technical solution.