工业冷却水垢的化学清洗工艺

本文介绍了钢制换热器碳酸盐垢的特点、清洗工艺及操作控制条件。     

化学清洗与物理清洗技术在工业清洗中的联合应用

通过对某换热器及某小区供暖系统管路的清洗实例,介绍了化学清洗与物理清洗应用技术。实践证明,两种技术相结合与使用单一的清洗技术相比,效率更高,效果更好。     

循环流化床锅炉两种化学清洗工艺比较

国华宁东电厂2×330MW循环流化床机组锅炉化学清洗均采用盐酸酸洗、柠檬酸漂洗、双氧水钝化工艺,不同之处在于其清洗工艺临时系统的设计.本文通过对这两台机组清洗工艺进行比较,为以后该类型锅炉酸洗临时系统的设计提供一定的参考.     

熔体过滤器清洗工艺优化

阐述了通过增加一道高压水清洗、热水洗以及对泡点试验和过滤芯组装等过程的优化,达到节能降耗,提高清洗效率,延长了过滤器使用周期,消除了此工序给聚酯生产带来的安全隐患。     

工业设备化学清洗的回顾与思考

根据多年从事石化设备化学清洗与防腐蚀的经历,试从设备不同的材料、设备不同的垢物、设备不同的类型、设备清洗失效的原因、化学清洗中的各种添加剂等进行分析。最后,对工业设备化学清洗的操作经验加以总结。     

工业磷酸一铵生产工艺的优化

云天化国际云峰分公司工业磷酸一铵(MAP)装置通过湿法磷酸净化剂脱硫改湿法磷酸矿浆脱硫、顺流加料蒸发流程改逆流加料蒸发流程、母液再脱硫循环、滤渣和废水综合利用等一系列技术改造,优化了工艺,产量稳步提升,原料和能耗大大降低,提高了磷酸一铵生产的综合效益。     

丁二烯装置的新型清洗工艺

以中海壳牌南海石化80万t／a乙烯项目16．5万t／／a丁二烯装置的化学清洗工程为实例,介绍一种新型的清洗工艺,此种工艺壳牌公司已在国外成功应用于丁二烯的装置（乙腈法）开车前的化学清洗。     

Optimization of hollow fiber membrane cleaning process for microalgae harvest

Biodiesel made from microalgae could be a possible replacement for fossil fuel. The separation of microalgae from their culture medium is a critical process in biotechnology. Membrane techniques seem to be effective, reliable, and safe, despite some limitations such as the progressive fouling and the associated decline in flux. Microalgae harvested from membranes have less chemical contamination and therefore membrane systems are more environmentally friendly than other harvesting techniques. We used a microfiltration (MF) system to concentrate the microalgae Tetraselmis sp. KCTC12236BP. Two cleaning processes, forward flushing and backwashing, were assessed to minimize the fouling required to concentrate the microalgae Tetraselmis sp. KCTC12236BP. It was concluded that backwashing was a more effective method than forward flushing. Furthermore, higher frequencies of backwashing greatly improved the membrane flux. However, even though the optimum cleaning frequency for maintaining high flux was every 5 min, from the perspective of microalgae concentrate and energy consumption, better results were obtained when backwashing was applied every 10 min. Under these conditions the microalgae culture reached 90% concentration in 60 min.     

工业锅炉水垢类型及化学清洗对策

叙述了工业锅炉水垢的形成、组分、特点及化学清洗方法.     

超超临界机组化学清洗工艺的选择

超超临界机组结构复杂、设备材质种类较多,保证化学清洗质量,防止设备损坏,正确选择清洗工艺尤为重要,本文对酸清洗介质及其清洗工艺进行了选择和分析,列出了可供选用的清洗工艺。     

化学清洗及干燥方法对盖玻片亲水性的影响

通过测试盖玻片对水的动态接触角,研究不同的化学清洗、晾干和烘干以及烘干时间对盖玻片的亲水性的影响。结果表明,在食人鱼溶液、氨水双氧水溶液(H2O2/NH4OH/H2O,1∶1∶5,体积比)、盐酸双氧水溶液(HCl/H2O2/H2O,1∶1∶6,体积比)和NaOH溶液(5%)等4种洗涤液中,用食人鱼溶液清洗或依次用食人鱼溶液、氨水双氧水溶液和盐酸双氧水溶液清洗的盖玻片的亲水性较好;长时间晾干或烘干皆对亲水性不利,高温烘干,最好选择100℃、1~2 h。     

酸刺沟选煤厂分选工艺的优化

酸刺沟选煤厂实际入洗原煤与设计所采用的煤样煤质差别较大,而且选煤厂的原煤仓与产品仓储量不足,影响了正常生产;针对这种情况,提出了对不同入洗原煤采取不同的洗选及入仓方案,实践表明,该方案满足了用户要求,提高了选煤厂经济效益。     

火力发电厂化学清洗的钝化工艺探讨

分析了火力发电厂化学清洗常用钝化剂的特点,比较了不同钝化剂的使用条件和保护效果,讨论了钝化处理的发展趋势和技术要点。     

某基建锅炉化学清洗效果偏离的情况分析

某基建锅炉的化学清洗后腐蚀速率超标,省煤器除垢不彻底.通过分析这次清洗的清洗工艺、系统和实施过程,解释了产生清洗效果偏离的原因.     

化学试剂预处理玻璃表面防尘保洁实验

应用玻璃清洗剂和TiO2试剂对载玻片表面进行预处理,将其按照不同角度(与水平面夹角)放置一定时间进行采样,研究不同时间载玻片表面沉积、粘附粉尘微颗粒的规律和清洗的难易程度,以便分析不同试剂预处理玻璃表面的防尘效果和清洗粘附粉尘的功效及其影响因素。研究发现:1)在相同条件下,经过试剂预处理的载玻片表面粘附的粉尘比较容易清洗干净,玻璃表面经预处理后具有一定防尘保洁功能。2)载玻片粘附粉尘的时间越长,越难清除。3)夹角为0°、45°时,清洗前后载玻片的粉尘微颗粒总数变化与采样时间成正比关系,夹角为90°时则不明显,说明后者主要以物理化学粘附为主,比前者重力自然沉降粘附作用力大,不易清除。4)微颗粒平均粒径与采样时间、放置夹角和试剂类型没有明显关系,粒径主要集中在12~22μm,遮光比的变化与载玻片粘附的微颗粒总数变化类似。     

多功能清洗预膜剂在工业循环水不停车清洗中的应用

分析了常见清洗、预膜药剂在循环冷却水系统不停车清洗应用中存在的问题,并着重介绍了多功能清洗、预膜剂KW-424的特点和它能解决这些存在问题的机理及在化工装置中的应用实例。     

Environmentally benign chemical additives in the treatment and chemical cleaning of process water systems: Implications for green chemical technology

Supersaturated process waters high in silicates frequently result in deposition of colloidal silica or metal silicate salts. Silica cannot be inhibited by conventional phosphonate mineral scale inhibitors. Chemical cleaning poses hazards and requires operational shut-downs. This paper is focused on a dual approach for silica scale control, inhibition of colloidal silica formation and colloidal silica dissolution in water technology applications by use of designed chemical approaches. The additives used for silica inhibition were polyaminoamide dendrimers (PAMAM) and polyethyleneimine (PEI), in combination with carboxymethyl inulin (CMI) and polyacrylate (PAA) polymers. In principle, silica inhibition is a function of time and inhibitor dosage. Amine-terminated PAMAM-1 and 2 dendrimers as well as PEI combined with anionic polymers, such as CMI and PAA, seem to have a significant inhibitory effect on silica formation, most likely at its earlier stages where the reaction products are oligomeric silicates. CMI and PAA assist the inhibitory action of PAMAM-1 and 2 and PEI by alleviating formation of insoluble SiO₂-PAMAM precipitates. This most likely occurs by partial neutralization of the positive charge that exists in –NH⁺₃ surface groups. Increase of anionic polymer dosage above a certain threshold has a detrimental effect on the activity of the cationic inhibitors. In that case the polymer’s negative charge “overwhelms” the cationic charge of the inhibitor and poisons its inhibition ability. For silica dissolution, acetic, oxalic, citric acids, histidine and phenylalanine were used as potential replacements of ammonium bifluoride (NH₄F·HF). Silica dissolution is dependent in a rather unpredictable fashion on the structure of the dissolver, time and dosage. This paper continues our research efforts in the discovery, design and application of antiscalant additives that have mild environmental impact. These chemicals are also known as “green additives”.