重碳酸盐碱度对电吸附脱盐效果的影响研究

为了解重碳酸盐碱度对电吸附设备脱盐效果的影响,以乌鲁木齐高新区北区再生水厂的出水作为原水,对不同HCO3^-浓度情况下电吸附设备连续运行的脱盐效果进行了研究。结果表明,进水HCO3^-浓度为170、260和440mg／L三种工况下,电吸附设备连续运行6个周期,除第1周期对TDS、氯离子和总硬度的去除率较低外,其余5个周期对三者及HCO3^-的去除率均呈逐渐下降的趋势,在HCO3^-浓度为440mg／L时,去除率下降最为明显;与其他离子不同的是,进水HCO3^-浓度越高,HCO3^-去除率越高,且第1周期去除率最高。分析认为在高重碳酸盐碱度工况下,HCO3^-与钙等硬度离子相互作用,导致电极板结垢,从而影响电吸附设备的脱盐效果。另外,在极板结垢的基础上,对原水中的重碳酸盐进行酸化吹脱,在进水HCO3^-浓度为100mg／L条件下设备连续运行,结果发现进水HCO3^-浓度较低时,可改善电吸附设备的脱盐效果。     

浅谈太阳能电池生产用超纯水的工程设计

宜兴某太阳能电池生产厂以市政自来水作为太阳能电池生产用的纯水水源,该工程以超滤( UF )、反渗透( RO)和电除盐( EDI)的全膜法工艺为主,投产运行3年的结果表明,系统性能稳定,出水水质大大优于太阳能电池生产用水水质标准,可达到超纯水水质标准。     

Comparison of ANN,MVR, and SWR models for computing thermal efficiency of a solar still

In this paper, the viability of modeling the instantaneous thermal efficiency (η_ith) of a solar still was determined using meteorological and operational data with an artificial neural network (ANN), multivariate regression (MVR), and stepwise regression (SWR). This study used meteorological and operational variables to hypothesize the effect of solar still performance. In the ANN model, nine variables were used as input parameters: Julian day, ambient temperature, relative humidity, wind speed, solar radiation, feed water temperature, brine water temperature, total dissolved solids of feed water, and total dissolved solids of brine water. The η_ith was represented by one node in the output layer. The same parameters were used in the MVR and SWR models. The advantages and disadvantages were discussed to provide different points of view for the models. The performance evaluation criteria indicated that the ANN model was better than the MVR and SWR models. The mean coefficient of determination for the ANN model was about 13% and14% more accurate than those of the MVR and SWR models, respectively. In addition, the mean root mean square error values of 6.534% and 6.589% for the MVR and SWR models, respectively, were almost double that of the mean values for the ANN model. Although both MVR and SWR models provided similar results, those for the MVR were comparatively better. The relative errors of predicted η_ith values for the ANN model were mostly in the vicinity of ±10%. Consequently, the use of the ANN model is preferred, due to its high precision in predicting η_ith compared to the MVR and SWR models. This study should be extremely beneficial to those coping with the design of solar stills.     

聚丙烯腈纳滤膜的制备及其对氯化钙的去除

以聚丙烯腈为原料制备了荷正电纳滤膜。分别采用热失重分析、FTIR、SEM对膜表面官能团及膜微观形貌进行了表征。考察了聚乙二醇添加剂、料液中氯化钙质量浓度、渗透侧流速等制备条件和操作条件对溶液中氯化钙去除率的影响。实验结果表明：以聚丙烯腈为原料、不添加聚乙二醇制备荷正电纳滤膜,在料液中氯化钙质量浓度为45mg/L、渗透侧流量为0.160mL/s的条件下,钙离子去除率可达96.0%;经蒸馏水冲洗再生后,该膜对钙离子去除率仍可达94.0%。     

Pesticide wastewater treatment using the combination of the microbial electrolysis desalination and chemical-production cell and Fenton process

• MEDCC combined with Fenton process was developed to treat real pesticide wastewater. • Pesticide removal was attributable to desalination in the MEDCC. • High COD removal was attributable to organic distributions in different chambers. The combination of the microbial electrolysis desalination and chemical-production cell (MEDCC) and Fenton process for the pesticide wastewater treatment was investigate in this study. Real wastewater with several toxic pesticides, 1633 mg/L COD, and 200 in chromaticity was used for the investigation. Results showed that desalination in the desalination chamber of MEDCC reached 78%. Organics with low molecular weights in the desalination chamber could be removed from the desalination chamber, resulting in 28% and 23% of the total COD in the acid-production and cathode chambers, respectively. The desalination in the desalination chamber and organic transfer contributed to removal of pesticides (e.g., triadimefon), which could not be removed with other methods, and of the organics with low molecular weights. The COD in the effluent of the MEDCC combined the Fenton process was much lower than that in the perixo-coagulaiton process (<150 vs. 555 mg/L). The combined method consumed much less energy and acid for the pH adjustment than that the Fenton.     

Surface modification of mesoporous silica nanoparticle with 4-triethoxysilylaniline to enhance seawater desalination properties of thin-film nanocomposite reverse osmosis membranes

• Mesoporous silica nanoparticle was modified with 4-triethoxysilylaniline. • AMSN-based TFN-RO membranes were prepared for seawater desalination. • Water transport capability of the AMSN was limited by polyamide. • Polyamide still plays a key role in permeability of the TFN RO membranes. Mesoporous silica nanoparticles (MSN), with higher water permeability than NaA zeolite, were used to fabricate thin-film nanocomposite (TFN) reverse osmosis (RO) membranes. However, only aminoalkyl-modified MSN and low-pressure (less than 2.1 MPa) RO membrane were investigated. In this study, aminophenyl-modified MSN (AMSN) were synthesized and used to fabricate high-pressure (5.52 MPa) RO membranes. With the increasing of AMSN dosage, the crosslinking degree of the aromatic polyamide decreased, while the hydrophilicity of the membranes increased. The membrane morphology was maintained to show a ridge-and-valley structure, with only a slight increase in membrane surface roughness. At the optimum conditions (AMSN dosage of 0.25 g/L), when compared with the pure polyamide RO membrane, the water flux of the TFN RO membrane (55.67 L/m²/h) was increased by about 21.6%, while NaCl rejection (98.97%) was slightly decreased by only 0.29%. However, the water flux of the membranes was much lower than expected. We considered that the enhancement of RO membrane permeability is attributed to the reduction of the effective thickness of the PA layer.     

河北省应对水危机加快发展海水淡化的探讨

21世纪水危机严重威胁河北省经济社会发展。海水淡化是解决水危机问题的重要措施,具有良好的综合效益和发展前景。河北省海水淡化条件较好,基础比较雄厚,为此建议尽快编制河北省海水淡化规划,加快建设海水淡化工程,积极发展海水淡化装备制造业,并开展沿海热电厂非采暖季节利用气热淡化海水的实验研究。     

Wind‐Powered Desalination: An Estimate of Saline Groundwater in the United States1

James Androwski, Abraham Springer, Thomas Acker, and Mark Manone, 2011. Wind‐Powered Desalination: An Estimate of Saline Groundwater in the United States. Journal of the American Water Resources Association (JAWRA) 47(1):93‐102. DOI: 10.1111/j.1752‐1688.2010.00493.x Abstract: Increasing scarcity of freshwater resources in many regions of the world is leading water resource managers to consider desalination as a potential alternative to traditional freshwater supplies. Desalination technologies are energy intensive and expensive to implement making desalination using renewable energy resources a potentially attractive option. Unfortunately, saline groundwater resources are not well characterized for many regions hindering consideration of such technologies. In this assessment, we estimate the saline groundwater resources of the principal aquifers of the United States using a geographic information system and correlate these resources to wind resources potentially sufficient to supply the energy demand of desalination equipment. We estimate that 3.1 × 10¹⁴ m³ saline groundwater, total volume, are contained in 28 of the country’s principal aquifers known to contain saline groundwater. Of this volume, 1.4 × 10¹⁴ m³ saline groundwater are co‐located with wind resources sufficient for electrical generation to desalinate groundwater.     

国产海水淡化装置铝黄铜换热管腐蚀调查分析

目的了解国产万吨级LT-MED装置铝黄铜换热管的腐蚀情况。方法通过对设备现场调研和腐蚀产物分析,对换热管的腐蚀类型和腐蚀原因进行分析,并对其腐蚀的危害性进行判断。结果铝黄铜换热管在凝结水侧发生全面腐蚀和点蚀,在海水侧主要发生轻微脱锌腐蚀。结论铝黄铜换热管在凝结水中腐蚀率很低,其全面腐蚀可以接受。换热管在凝结水侧的点蚀轻微,可对其进行定期检测。铝黄铜在海水侧的脱锌腐蚀轻微,可以忽略。换热管腐蚀程度轻微,不影响水质和设备正常运行。     

海水淡化集成技术的相关研究

为了降低海水淡化的成本和能耗,对海水淡化的集成工艺进行相应研究。海水淡化集成技术主要分为两种形式:一是不同海水淡化工艺的集成,二是能源和海水淡化的集成。首先介绍了海水淡化工艺的相关集成技术,包括热法与热法集成、膜法与膜法集成、热法与膜法集成、预处理工艺与海水淡化的集成工艺;其次介绍了各种新能源与海水淡化耦合方式、代表工程及研究现状,最后对海水淡化集成技术的优化提出建议。