热除盐水洗脱强碱阴树脂二氧化硅的技术应用

１前言我厂水处理系统采用的是一级除盐工艺，除盐系统采用的是强阳加强阴装置，对于强碱性阴离子交换器来说，碱耗是一项重要的经济指标。长期以来，我们采用了各种方法降低碱耗，提高再生效果，但效果一直不太理想，碱耗很难降低。经过长时间的对阴树脂的研究与分析，我们根     

浮动阴床周期制水量下降原因分析及解决措施

对某热电厂浮动阴床周期制水量下降原因进行分析,制订出了最佳的阴树脂复苏工艺,并提出了具体的调整措施。调整后浮动阴床周期制水量明显恢复,提高了浮动阴床运行的经济性。     

电厂一级除盐系统技术改造

1前言广州市煤气公司广州油制气厂热电分厂共有 3套一级除盐设备 ,均为无顶压逆流再生固定床。阳床规格为180 0mm ,阴床为2 0 0 0mm ,阳床用盐酸再生 ,阴床用烧碱再生 ,再生废水全部排入中和池 ,经酸碱中和处理合格后外排。该系统运行多年 ,存在以下不足 :(1)失效床再生时 ,再生用除盐水流量用转子流量计计量 ,而再生液浓度只能通过酸碱计量箱液位计管内酸碱的下降速度进行控制 ,如再生阳床时要求下降速度为 0 7格 min ,阴床为 0 6格 min ,实际操作较难控制 ,不能保证合适的再生液浓度及再生液与树脂的接触时间 ,而采用逆流再生方法…     

精处理再生阴塔锥斗损坏原因分析及对策

发电厂凝结水精处理系统混床基本上都采用体外再生,高塔与锥斗分离技术是目前使用最为广泛的树脂分离技术。以金湾电厂精处理为例,分析了再生阴塔锥斗损坏的原因,并提出了一些行之有效的改进措施,对同样选用锥斗分离技术的同类型电厂具有较大指导意义。     

走新型工业化道路 大力发展循环经济

巨化股份公司电化厂创建于1959年，是巨化集团公司控股的巨化股份公司下属骨干生产厂，是全国大型氯碱企业和浙江省最大的氯碱生产企业。经过46年的艰苦创业，现已发展成为拥有液碱、固碱、液氯、盐酸、PVC树脂、VDC单体、PVDC乳液、PVDC树脂等10大类基本化工原料产品群的企业，烧碱生产规模位居国内前五位，离子膜烧碱装置成为从国外引进中工业化生产最好的装置，拥有了巨化唯一的国内自主知识产权的万吨级PVDC树脂技术。     

凝结水离子交换处理工艺中失效树脂的分离及再生

通过对炼油装置产生的汽机凝结水进行热回收、水中阴阳离子及电导值超标的处理、除氧处理等工艺,使处理后的凝结水达到除氧水的指标,满足锅炉上水要求。主要论述在采用Na+交换处理工艺中对失效树脂采用了有效分离工艺、设备及控制方式,确保失效树脂的有效再生,从而保证工艺出水合格同时减少了树脂补充量。通过实际生产运行,各项工艺指标达到设计值,取得较好的效果。     

阳再生塔内混合树脂电导率不合格原因分析

6号机树脂体外再生至阳塔混合正洗结束后,存在电导率不合格的情况。对于采用相同再生方式的5号机树脂,阳塔内混合正洗电导率能达到合格要求。因此,通过将6号机树脂再生与5号机进行比较,对6号机的再生要素和过程进行分析和梳理,发现阳塔混合正洗电导率不合格的主要原因是失效的树脂分离后阳树脂进酸结束没有能够充分置换。经过调整阳树脂的再生工况,阳树脂置换电导率值明显下降,有效地提高了阳树脂再生置换程度,使树脂阳塔混合正洗电导率达到设定要求。     

凝结水精处理系统树脂分离技术

随着我国大型发电厂的建设，机炉参数越来越高，对水汽品质的要求也越来越高。这就要求在保证补给水品质的同时，还必须保证疑结水的品质，才能确保给水的品质。在凝结水精处理中，树脂的再生分离至关重要，它直接影响到整套凝结水精处理系统的正常运行和出水品质，也是混床能否实现氨化运行的关键。本文简要介绍目前国内外具代表性和实用性的三种分离技术，供参考。1、树脂分离原理凝结水处理系统中，失效树脂的再生均采用体外再生方案，以确保深层混床树脂的高再生度，特别是混床采用氯化运行方式时，再生度的要求更高。要实现高再生度，…     

核电站凝结水精处理用离子交换树脂的研究进展

介绍了核电站凝结水精处理用离子交换树脂的应用现状、使用过程中出现的问题及最新研究进展;概述了对于凝结水精处理用离子交换树脂最重要的特性是阳树脂优异的抗氧化性能(低溶出物),阴树脂优异的抗有机物污染性能,凝胶型阳树脂搭配大孔型阴树脂是核电站凝结水精处理应用的趋势。     

凝结水精处理中影响树脂分层的原因浅析

发电厂凝结水精处理体外再生混床中的阴阳树脂，在返冲洗时就分层。本文改变树脂分离器的结构，进行试验，得到较好的分离效果。     

离子液体提取木质素及环氧树脂的合成

采用离子液体提取尾叶桉木木质素,以甲苯酚为酚化剂,浓硫酸为催化剂,对木质素进行酚化改性,再以NaOH为催化剂,将酚化木质素与环氧氯丙烷进行环氧化反应,合成木质素基环氧树脂。实验表明:当离子液体为[ChCl][Gly]、温度为90℃、时间为12 h、液固比为20∶1时,木质素的提取率达到93.73%,再生木质素纯度为96.3%;酚化木质素与环氧氯丙烷质量比为1∶2.5,NaOH质量分数为酚化木质素质量的20%,反应时间为3 h,反应温度为95℃,在此条件下,木质素环氧树脂的环氧值为0.364。     

关于UV行业用高纯聚醚精馏系统的研究

光固化技术(UV)是通过一定波长的紫外光照射,使液态的环氧丙烯酸树脂和UV单体高速聚合而成固态的一种光加工工艺。光固化(UV)技术是一项节能和清洁环保型技术,不仅节约能源,且不含溶剂、对生态环境有保护作用,不会向大气排放溶剂VOC和CO2,故被誉为"绿色技术"。介绍了UV行业用高纯聚醚的分离方法,主要是加热介质的确定方法、关键设备和自动化仪表的选用方法,解决了高纯聚醚精馏设计中存在的问题。     

Water management in alkaline anion exchange membrane fuel cell anode

Water management is an important issue for alkaline anion exchange membrane fuel cell (AAEMFC) due to its significant role in the energy conversion processes. In this study, a numerical model is developed to investigate the water transport in AAEMFC anode. The gas and liquid transport characteristics in the gas diffusion layer (GDL) and catalyst layer (CL) with different designs and under various operating conditions are discussed. The results show that the current density affects the liquid water distribution in anode most significantly, and the temperature is the second considerable factor. The stoichiometry ratio of the supplied reactant has insignificant effect on the liquid water transport in anode. The change of liquid water amount in anode with cathode relative humidity follows a similar trend with anode inlet relative humidity. Some numerical results are also explained with published experimental and modeling data with reasonable agreement.     

A preliminary study on boron removal from Kizildere/Turkey geothermal waste water

A study is made of boron removal from Kizildere/Turkey geothermal waste water using the boron selective resin Amberlite IRA 743. The resin in salt form has no boron removal capacity if the solution is unable to neutralize the released acid during the exhaustion period. In the case of Kizildere waste water, with a pH value of 8.9 and high HCO₃⁻ content, single stage regeneration is feasible and the exhausted resin can be regenerated economically. According to a preliminary estimate, the electricity production cost would rise by 1 ¢/kWh.     

Hybrid energy system for hydrogen production in the Adrar region (Algeria): Production rate and purity level

The following work treat the prediction of the production rate and purity level of hydrogen produced by an alkaline electrolyzer fed by a renewable source in a hybrid energy system HES in the locality of Adrar in the south of Algeria. This work is made for different renewable energy penetration rate from 0% to 60% of conventional power (Genset generator). The cell electrolyzer model permits to predict the production rate of hydrogen with accuracy, according to operating parameters, climatic conditions and the load of the site of Adrar. The study permits to introduce a model of hydrogen purity level based on the operating parameters and the power supplying the alkaline electrolyzer. It also shows that the great influence of the intermittent energy supplying the electrolyzer on the production rate and purity level of hydrogen. The prediction of production rate and purity level by the models allow to obtain a distribution and storage of hydrogen produced according to predetermined selection criteria imposed by the operator.In the process of electrolysis, the oxygen is considered as by-product of the hydrogen production. The amount and purity level were estimated jointly.An HES-H₂ production program under MATLAB^®/SIMULINK^® has been developed to simulate the hourly evolution of the production rate and purity level of hydrogen and oxygen produced by an electrolyzer for different penetration rate of renewable energies in an HES.     

Performance comparison of modified poly(vinyl alcohol) based membranes in alkaline fuel cells

There are several problems which are holding back the use of fuel cells. The utilization of fuel cells depends on the start-up costs which are very high due to the use of expensive materials for their construction. In that respect, we describe a cost-effective alkaline fuel cell (AFC) that uses solid, polymer based, membrane instead of conventionaly used, highly concentrated, corrosive, liquid alkaline electrolyte. This approach to AFC is potentially the basis of a simple, low-cost system, that can solve one of the problems of the highly-efficient and environment-friendly AFC.The focus of this paper are low cost composite alkaline membranes, based on poly(vinyl alcohol) (PVA). The PVA matrix is made by solution cast method and gamma irradiation crosslinking. Three different types of membranes are obtained in this manner - plain PVA membrane, PVA membrane cross-linked using gamma irradiation (γ-PVA) and composite PVA membrane doped with Mo (PVA-Mo). These membranes are immersed in the alkaline solution and investigated as anion exchange membranes. The performance of the solid alkaline fuel cells (SAFCs) containing these PVA membranes has been studied under hydrogen and oxygen gas flow on the Pt/C catalyst. Both, γ-PVA and PVA-Mo membranes are modified to absorb larger amounts of alkaline solution than the PVA membrane, thus greatly improving the performance of the SAFC, in terms of output power. This is clearly indicated in the polarisation curves. The electrochemical impedance spectroscopy measurements during the SAFC operation were also performed to give better insight in the effect observed. Investigation presented in this paper clearly indicates that solid alkaline PVA membranes can be used for the construction of the SAFCs.     

High performance direct liquid fuel cells powered by xylose or glucose

In this work, we report the first abiotic, direct liquid fuel cells powered by the monosaccharide xylose using both a fully alkaline fuel cell (with anion exchange membrane) and a split pH fuel cell (with cation exchange membrane). We also report that the same fuel cells can be used with the monosaccharide glucose to produce much higher maximum power density than previously reported for abiotic, direct glucose fuel cells. This first alkaline direct xylose fuel cell (DXFC) produces a maximum power density of 57 mW cm⁻² at optimum conditions, while the split pH DXFC produces a maximum power density of 160 mW cm⁻². Our significantly improved alkaline direct glucose fuel cell (DGFC) produces 90 mW cm⁻² at optimum conditions, while the split pH DGFC produces 189 mW cm⁻². In addition to being high performing, these sugar molecules are naturally abundant, renewable, and known to convert to valuable products such as gluconic acid, glucaric acid, and xylonic acid during electrochemical oxidation. Other fuel cell and electrochemical cell data is also reported herein to understand the role of pH and fuel concentrations on behavior toward the electrochemical oxidation of these sugar molecules in alkaline media.     

Modeling of hydrogen alkaline membrane fuel cell with interfacial effect and water management optimization

In this study, a whole-cell 3D multiphase non-isothermal model is developed for hydrogen alkaline anion exchange membrane (AAEM) fuel cell, and the interfacial effect on the two-phase transport in porous electrode is also considered in the model. The results show that the insertion of anode MPL, slight anode pressurization and reduction of membrane thickness generally improve the cell performance because the water transport from anode to cathode is enhanced, which favors both the mass transport and membrane hydration. The effect of cathode MPL is generally insignificant because liquid water rarely presents in cathode. It is demonstrated that slight pressurization of anode, which might not lead to apparent damage to the membrane, can effectively solve the anode flooding and cathode dryout issues.     

Poly(arylene ether ketone) with pendant pyridinium groups for alkaline fuel cell membranes

Using the step-growth polycondensation reaction, poly(arylene ether ketone) (PAEK) and activated poly(arylene ether ketone)-NHS intermediates (PAEK-N) were synthesized. PAEK-NHS intermediates with pyridinium groups (PAEK-PYR) were obtained by adding different amounts of PYR groups. The successful syntheses of PAEK, PAEK-N, and PAEK-PYR were confirmed by nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. Several important membrane properties (e.g., ionic exchange capacity (IEC), water uptake, anion conductivity, and thermal and mechanical stability) were investigated for their applications in alkaline fuel cells. Water uptake, swelling ratio, anion conductivity, and IEC increased with increasing PYR contents, while the mechanical properties decreased. Among a series of prepared membranes, the PAEK-PYR100 and PAEK-PYR125 membranes showed IEC and anion conductivity values that were higher than those of a commercial AHA membrane. Also, all of the prepared membranes were thermally stable up to 255 °C and show excellent chemical stability in alkaline conditions.     

Polyaryl piperidine anion exchange membranes with hydrophilic side chain

Recently, the development of high-performance and durable anion exchange membranes has been a top priority for anion exchange membrane fuel cells. Here, a series of polyaryl piperidine anion exchange membranes with hydrophilic side chain (qBPBA-80-OQ-x) are prepared by the superacid-catalyzed Friedel-Crafts reaction. AFM images show that the hydrophilic side chain and hydrophobic main chain form a distinct microphase separation structure. The AEMs of qBPBA-80-OQ-100 and qBPBA-80 have close mechanical strength, but the ionic conductivity of the former (81 mS/cm, 80 °C) is higher than the latter (73 mS/cm, 80 °C). In addition, qBPBA-80-OQ-100 AEM loses by 15.0% after an alkaline treatment of 720 h, while qBPBA-80 AEM loses by 17.8%. The results indicate that the introduction of hydrophilic side chain not only promotes the formation of microphase separation structure, but also improves the ionic conductivity and alkaline resistance of polyaryl piperidine AEMs.