循环冷却水的阻垢剂研究

由于蒸发浓缩作用导致成垢离子浓度成倍增加,循环冷却水系统出现严重结垢,附着在管道或传热面上,不仅造成换热效率降低,同时易产生垢下腐蚀。选用氨基三亚甲基膦酸（ATMP）、1-羟基亚乙基-1,1-二膦酸（HEDP）、乙二胺四亚甲基膦酸（EDTMP）、TM-604和TM-1600及三聚磷酸钠常用阻垢剂,研究对循环水中常见的CaCO3垢的阻垢作用,并筛选出性能较好的2种阻垢剂进行复配。实验结果证明,最佳复配比例为ATMP∶TM-604=1∶1时,阻垢效果最好,且稳定性也较好。     

几种有机膦酸水稳剂的阻垢性能对比实验研究

有机膦酸是一类具有缓蚀、阻垢性能的多功能水稳剂,已在工业循环冷却水中广泛应用.文章采用鼓泡法,评定了乙二胺四甲叉膦酸(EDTMP)、二乙烯三胺五甲叉膦酸(DTPMP)、2-膦酸基-1,2,4-丁烷三羧酸(PBTCA)对碳酸钙、磷酸钙、磷酸锌等污垢的阻垢性能.实验结果表明:在阻垢剂用量5 mg/L,温度60℃,运行时间6 h,Ca2 浓度为240 mg/L的条件下,PBTCA的阻碳酸钙和磷酸锌垢效果最佳,阻垢率分别为94.34%和67.87%;DTPMP阻磷酸钙垢效果最佳,用药量为4.4 mg/L时,阻垢率达到99%.     

PASP和ATMP复合阻垢剂阻垢性能研究

采用静态阻垢法对聚天冬氨酸(PASP)与氨基三亚甲基膦酸(ATMP)复配物阻垢性能进行研究。考察阻垢剂添加量、温度、Ca2+浓度、HCO3-浓度、恒温时间对阻垢率的影响。结果表明,复配物的阻垢性能较单一的聚天冬氨酸有一定的提高。复配物的最佳质量配比为1∶1,PASP和ATMP总加入量为4 mg/L时效果最佳,阻垢率达86%。复配物阻垢性能受温度、时间、HCO3-浓度的影响较小,受Ca2+浓度的影响较大。对复合阻垢剂进行了经济性评价,复合阻垢剂可降低单独使用时的成本。     

三种阻垢剂阻硫酸钙垢协同效应的研究

采用电导法研究了聚天冬氨酸（PASP）、羟基亚乙基二膦酸（HEDP）、2-膦酸基-1,2,4三羧基丁烷（PBTCA）三种阻垢剂单组分时的阻CaSO4垢性能以及二元复配、三元复配后的协同效应。考察了pH、温度等条件对二元复配物阻垢性能的影响。实验表明：二元组合除PASP和PBTCA之间存在协同效应,其余组合不存在协同效应...     

复合阻垢剂PASP-ATMP的协同效应及影响因素研究

采用静态阻垢法,研究了聚天冬氨酸(PASP)与氨基三甲叉膦酸(ATMP)复配体系的协同效应,考察阻垢剂添加量、温度、pH值、Ca2+浓度、HCO3-浓度对阻垢性能的影响。结果表明,复配体系的阻垢性能较单一阻垢剂好,PASP/ATMP质量比在2∶3时,阻垢性能最优,当复合阻垢剂PASP-ATMP投加量为5 mg/L时,阻垢率高达93.04%。复配体系阻垢性能随温度、pH值、Ca2+浓度、HCO3-的增加虽然有所下降,但仍表现出一定钙容忍度及适合高pH值、高HCO3-环境使用等特性。     

新型阻垢剂GDMP的合成及其阻垢性能的研究

用甘氨酸、甲醛、亚磷酸合成了新型阻垢剂甘氨酸二亚甲基膦酸(GDMP),并将其与其他常用阻垢剂HEDP、PBTCA、ATMP、PESA、PASP进行二元复配.用碳酸钙沉淀法对GDMP单剂及其二元复配物的阻垢性能进行分析.结果表明,GDMP与其他常用阻垢剂复配有一定的协同效应,可用于改进现有工业冷却水阻垢剂配方.并对其阻垢机理进行了初步讨论.     

三氯异氰尿酸对有机磷缓蚀阻垢剂性能的影响

试验研究了三氯异氰尿酸(TCCA)对羟基亚乙基二膦酸(HEDP)、2-膦酰基丁烷-1,2,4-三羧酸(PBTCA)、羟基膦乙酸(HPAA)和多氨基多醚基亚甲基膦酸(PAPEMP)四种有机磷缓蚀阻垢剂的分解作用和对它们缓蚀、阻垢性能的影响.结果表明,三氯异氰尿酸对有机磷类缓蚀阻垢剂有分解作用,其分解程度为PAPEMP＞HPAA＞HEDP＞PBTCA;三氯异氰尿酸可使水的pH降低,造成碳钢迅速腐蚀;随着水中三氯异氰尿酸浓度的增加,HEDP、PBTCA和HPAA的阻CaCO3垢率先增加而后降低,PAPEMP的阻CaCO3垢率则持续降低.     

油田水阻垢剂的阻垢机理及其研究进展

油田水垢组成复杂,除传统的钙、镁外,钡、锶成分也较突出。针对阻垢剂的阻垢机理以及阻垢剂的发展情况,笔者在传统单剂基础上,以有机膦酸盐阻垢剂2-膦酸丁烷-1,2,4-三羧酸（PBTCA）：羟基亚乙基二磷酸（HEDP）=1：2复配,对CaCO3产生了最佳的阻垢效果。将马来酸（MA）、醋酸乙烯酯（VC）、丙烯酸甲酯（MAC）在引发剂的作用下与有机膦酸盐类阻垢剂复配,合成防钡锶垢的阻垢剂DY-2,加药量50mg／L,其阻垢率达99．5％。绿色阻垢剂PASP和PESA的阻垢效果也较明显。     

模拟高矿化度矿井水阻垢缓蚀剂的研究

采用碳酸钙沉积法测定5种单一阻垢剂对CaCO3的阻垢效果,聚环氧琥珀酸（PESA）的最佳使用质量浓度为15mg／L时,其阻垢率达到75．3％;在含磷类阻垢剂中,2-膦酸基-1,2,4-三羧基丁烷（PBTCA）的最佳使用质量浓度为20mg／L时,其阻垢率达到76．1％。PESA与PBTCA的浓度比为10：15时,阻垢率可达94．2％。通过正交实验和平行实验,确定三元阻垢剂的最佳配比,即ρ（PESA）：ρ（PBTCA）：ρ（TS-623）（丙烯酸-AMPS三元共聚物）=8：12：8,阻垢率达到96．5％,阻垢效果最佳,且磷含量较低,价格合理,是较为理想的复配型阻垢剂。静态阻垢实验和中试规模的动态试验结果表明,本实验研究的阻垢缓蚀剂能完全适用于工业循环冷却水系统。     

复合有机阻垢剂在锅炉水中的阻垢性能

以聚丙烯酸钠（PAA）为主体,辅之以1-羟基-乙叉-1,1-二膦酸（HEDP）和氨基三亚甲基膦酸（ATMP）等有机磷化合物复配成全有机复合阻垢剂,探讨了复合阻垢剂的性能。重点考察了阻垢剂浓度、钙离子浓度、pH值和温度等因素对阻垢性能的影响。实验结果表明,该阻垢剂在较宽温度范围内具有良好的阻垢性能。     

碳酸钙在流动过冷沸腾条件下的结垢机理研究

Fouling of heat transfer surfaces during subcooled flow boiling is a frequent engineering problem in process industries. It has been generally observed that the deposits in such industrial systems consist mainly of calcium carbonate （CaCO3）, which has inverse solubility characteristics. This investigation focused on the mechanism to control deposition and the morphology of crystalline deposits. A series of experiments were carried out at different surface and bulk temperatures, fluid velocities and salt ion concentrations. It is shown that the deposition rate is controlled by different mechanism in the range of experimental parameters, depending on salt ion concentration. At higher ion concentration, the fouling rate increases linearly with surface temperature and the effect of flow velocity on deposition rate is quite strong, suggesting that mass diffusion controls the fouling process. On the contrary, at lower ion concentration, the fouling rate increases exponentially with surface temperature and is independent of the velocity, illustrating that surface reaction controls the fouling process. By analysis of the morphology of scale, two types of crystal （calcite and aragonite） are formed. The lower the temperature and ion concentration, the longer the induction period and the higher the percentage of calcite nreciDitated.     

Effects of PAA and PBTCA on CaCO3 Scaling in Pool Boiling System

Formation of mineral scales on heat exchangers is a persistent and expensive problem. In the presentpaper, the calcium carbonate scale inhibition by two inhibitors, polyacrylic acid (PAA) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) has been studied in a pool boiling system. It is found that PBTCA has abetter inhibition effect than PAA under the identical conditions. X-ray diffraction(XRD) and Fourier transform-infrared(FTIR) analyses demonstrate that the content of vaterite increases as inhibition effects increase. Themetastable crystal forms of vaterite and aragonite are stabilized kinetically in the presence of inhibitors. Therelationship between the inhibition effect and the fractal dimension has also been investigated. The result showsthat the fractal dimension is higher in the presence of inhibitors. The better the inhibition effect, the higher thefractal dimension. The step morphology was observed by atomic force microscopy (AFM) images. It is shown thatthe step space on the calcium carbonate surface increases in the presence of inhibitors. Moreover, with the increaseof inhibition effect, both the step space and the fractal dimension increase. The step bunching is found on thecalcium carbonate by AFM. The better the inhibition effect of the inhibitor, the slower the step velocity in theunbunched location. As a result, the step space becomes wider in the presence of PBTCA than that in the presenceof PAA.     

聚天冬氨酸复配物及其阻垢缓蚀性能

通过合成丙烯酸-丙烯酸乙酯-衣康酸（AA-AE-IA）三元共聚物阻垢分散剂，开发出一种具有优良阻垢分散和缓蚀性能的新型聚天冬氨酸复配物（PASP＋AA-AE-IA＋PBTCA），考察了不同条件下聚天冬氨酸复配物对碳酸钙和硫酸钙的阻垢性能。利用扫描电子显微镜对碳酸钙晶型进行了分析，结果表明：聚天冬氨酸复配物可使碳酸钙晶体发生明显的扭曲现象，碳酸钙结晶更加细小分散。     

羧甲基葡聚糖的快速沉降法阻垢特性研究

工业循环冷却水中的碳酸钙污垢一直是困扰工业生产者的重要问题,使用快速沉降法（FCP）研究了不同浓度的羧甲基葡聚糖对于碳酸钙污垢的抑制作用。控制溶液中的钙离子浓度为200 mg/L,羧甲基葡聚糖的浓度分别为0.5、1、2和4 mg/L时,对羧甲基葡聚糖的阻垢性能进行分析。结果表明,羧甲基葡聚糖对于减缓碳酸钙的成核过程有明显效果,此外,它也显著降低了碳酸钙成核后晶体的生长速率。当羧甲基葡聚糖的浓度为4 mg/L时,羧甲基葡聚糖对于碳酸钙的成核及晶面生长起到了完全抑制的作用,对于工业应用中碳酸钙的防垢处理,提升换热效率具有借鉴意义。     

池式沸腾下PAA与PBTCA对CaCO3结垢的影响

Formation of mineral scales on heat exchangers is a persistent and expensive problem.In the present paper,the calcium carbonate scale inhibition by two inhibitors,polyacrylic acid(PAA) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) has been studied in a pool boiling system.It is found that PBTCA has a better inhibition effect than PAA under the identical conditions.X-ray diffraction (XRD) and Fourier transform-infrared(FTIR) analyses demonstrate that the content of vaterite increases as inhibition effects increase.The metastable crystal froms of vaterite and aragonite are stabilized kinetically in the presence of inhibitors.The relationship between the inhibition effect and the fractal dimension has also been investigated.The result shows that the fractal dimension is higher in the presence of inhibitors.The better the inhibition efect,the higher the fractal dimension.The step morphology was observed by atomic force microscopy(AFM) images.It is shown that the step space on the calcium carbonate surface increases in the presence of inhibitors.Moreover,with the increase of inhibition effect,both the step space and the fractal dimension increase.The step bunching is found on the calcium carbonate by AFM.The better the inhibition effect of the inhibitor,the slower the step velocity in the unbunched location.As a result,the step space becomes wider in the presence of PBCA than that in the presence of PAA.     

Mathematical modelling of mixed salt precipitation during convective heat transfer and sub-cooled flow boiling

The main purpose of this investigation was to study the mechanisms of mixed salt crystallisation fouling on heat transfer surfaces during convective heat transfer and sub-cooled flow boiling conditions. In the present investigation, the effects of various operating parameters such as solution composition and hydrodynamics of the system, on crystallisation fouling of mixtures of calcium sulphate and calcium carbonate have been studied experimentally. After clarification of the effects of operating parameters on the deposition process, the results of the experiments were used to develop a mechanistic model for prediction of fouling resistances, caused by crystallisation of mixed salts, under convective heat transfer and sub-cooled flow boiling conditions. Model predictions were compared with the measured experimental data when calcium sulphate and calcium carbonate form deposits on the heat transfer surface simultaneously. Deviations ranging from 6% to 25% were observed which confirm the suitability of the model.     

含膦酰基聚天冬氨酸的阻垢性能研究

自行制备了含膦酰基聚天冬氨酸。与PBTCA、HPA相比,含膦酰基聚天冬氨酸的阻CaCO3垢性能相当,具有比较突出的阻Ca3(PO4)2垢以及稳定水中Zn^2 的能力。含膦酰基聚天冬氨酸与PBTCA、HPA等药剂复配得到的低磷药剂性能达到常用有机磷药剂的水平。     

The effect of surface properties on CaSO4 scale formation during convective heat transfer and subcooled flow boiling

In this paper the effects of surface energy and surface roughness on the deposition of calcium sulphate during convective and subcooled flow boiling heat transfer to aqueous CaSO₄ solutions are studied. The surfaces of several test heaters have been treated by Ion Beam Implantation, Unbalanced Magnetron Sputtering, Mixed Sputtering and Plasma Arc Deposition to reduce surface energy. One heater was electropolished to reduce surface roughness and one heater was etched by an electrochemical method to increase surface roughness. Fouling runs with these heaters, and with an untreated surface as control, were carried out at different heat fluxes, flow velocities and salt concentrations. The results show that heat transfer surfaces with low surface energy experienced significantly reduced fouling, while electropolishing did not have a notable beneficial effect. The combined effect of reduced surface energy and flow velocity on fouling reduction is considerably stronger than previously reported for pool boiling.     

聚环氧琥珀酸及其复配物阻垢缓蚀性能的研究

针对火电厂循环冷却水水质研究了聚环氧琥珀酸(PESA)的阻垢性能,并同PASP、MA-AA、ATMP等阻垢剂的阻垢效果进行了比较.实验结果表明:PESA阻垢效果优良.比PASP、MA-AA阻垢效果更优,比ATMP阻垢效果稍差.针对凝汽器铜材质(HSn-70A)研究了单一聚环氧琥珀酸的缓蚀性能,开发了与之复配的复合配方,筛选出的最佳复配方案为10mg/L PESA+0.5 mg/L BTA+2mg/L Zn2++10mg/L葡萄糖酸钠,在此条件下铜的腐蚀率仅为0.0005mm/a.