电导法评定阻垢剂的阻垢性能

介绍了一种评价阻垢剂阻垢性能的新方法。这种方法基于溶液电导率的测定原理，是通过在加入阻垢剂和不加阻垢剂的特定水环境下测定各种成垢化合物的过饱和度来实现。此法能对各种阻垢剂的阻垢性能进行良好的区分。通过与评定阻垢剂性能的国家标准——鼓泡法的比较，证明此法简便、快捷、重现性好，可信度高。     

阻垢剂阻BaSO4垢性能的电导滴定评价法

采用一种基于电导滴定原理的评价方法,通过测定电导滴定过程中不同阻垢剂在相同浓度下所能维持的BaSO4的最大相对过饱和度来评价阻垢性能。实验对阻垢剂聚环氧琥珀酸(PESA)、聚天冬氨酸(PASP)、二亚乙基三胺五亚甲基膦(DEPTMP)、六偏磷酯钠(SHMP)阻BaSO4垢的性能分别采用了电导滴定法及静态阻垢法进行测定并比较。电导滴定法对阻垢剂阻BaSO4垢性能的测试结果表明,阻垢剂PESA、PASP、DTPMP和SHMP对BaSO4垢的阻垢能力大小为:PESA>PASP>DEPTMP>SHMP,这与静态阻垢法的实验结果一致,表明电导滴定法与静态阻垢法对阻垢剂阻BaSO4垢的评价结果具有一致性,电导滴定法评价阻垢剂对BaSO4垢的阻垢性能具有快速、简单、易行的优点。而且实验表明,电导滴定法的RSD为0.020,而静态阻垢法为0.069,说明电导滴定法的重现性优于静态阻垢法。该法还可用于评价阻垢剂对BaSO4垢的协同阻垢效应。     

绿色阻垢剂聚天冬氨酸的研究进展

聚天冬氨酸是一种无毒、无磷、可生物降解的绿色环保型水处理剂,具有良好的阻垢性能.在简要回顾阻垢剂的发展历史以及聚天冬氨酸合成的基础上,综述了近几年聚天冬氨酸作为阻垢剂的研究进展.主要是通过在侧链上引入具有阻垢效果的功能基团,改性后的聚天冬氨酸具有更好的阻垢性能或其他性能.对这一领域的发展方向做了展望.     

一种智能型阻垢剂性能快速评定装置

针对我国目前指导水处理剂阻垢性能评定的化工行业标准HG/T2160-1991——鼓泡法及其评定设备的不足,基于国外上世纪末提出的电导滴定法,研制了一种一体化智能型阻垢剂性能的快速评定装置。该装置基于微机技术应用平台,实现了水处理剂阻垢性能评定的全程自动化:建立了滴定过程中电导率——滴定液容积变化曲线突降点位置的预测算法和相应软件,奠定了阻垢效果的智能评定基础;研制了数据采样间隔自动跟踪、匹配蠕动泵转速的自动滴定装置,提高了滴定分辨率和拐点位置确定精度;自制了高灵敏度、高精密度的半导体温度传感器及其测点位置调节部件,消除了滴定过程中温度对检测评定的干扰;定量确定了测定池系统表面积垢对检测评定的影响,拟定了相应清洗程序。与现有各评定方法和设备相比,本仪器的精准度高、重复性好、评定快捷、操作简便、容重小、能耗小,能更好满足水处理剂生产企业和众多行业用户对水处理剂阻垢性能评定的需求,有望成为鼓泡法评定设备的换代产品。     

膦系阻垢剂对碳酸钙阻垢机理的研究

在模拟循环水中,通过静态阻垢实验研究了HEDP,PBTCA,ATMP和EDTMP对碳酸钙的阻垢性能,在相同的加药浓度下(按物质的量浓度计)阻垢性能的强弱顺序为HEDPPBTCAATMPEDTMP;同时采用分子动力学方法,模拟计算了阻垢剂负二价离子与方解石(104),(102),(202)和(113)面的相互作用.结果表明:阻垢剂分子中的膦酸基团和羧酸基团与碳酸钙中的Ca2+形成的离子键对吸附起到了主要作用,同时阻垢剂与晶面间存在较弱的范德华力相互作用.阻垢剂与各晶面的结合能强弱顺序为(113)≥(102)≥(202)(104);分子中的羟基易与垢晶面形成氢键而加强阻垢效果;羧基的位置不同对阻垢作用的影响不同.将静态阻垢的实验结果与分子动力学模拟结果进行了相关性分析,发现阻垢剂在(104)面和(102)面上的吸附对阻垢作用的贡献较大.     

膦系阻垢剂阻碳酸钙垢机理的研究

在模拟循环水中, 通过静态阻垢实验研究了HEDP, PBTCA, ATMP和EDTMP对碳酸钙的阻垢性能, 在相同的加药浓度下(按物质的量浓度计)阻垢性能的强弱顺序为HEDP＞PBTCA＞ATMP＞EDTMP; 同时采用分子动力学方法, 模拟计算了阻垢剂负二价离子与方解石(104), (102), (202)和(113)面的相互作用. 结果表明: 阻垢剂分子中的膦酸基团和羧酸基团与碳酸钙中的Ca^2＋形成的离子键对吸附起到了主要作用, 同时阻垢剂与晶面间存在较弱的范德华力相互作用. 阻垢剂与各晶面的结合能强弱顺序为(113)≥(102)≥(202)＞(104); 分子中的羟基易与垢晶面形成氢键而加强阻垢效果; 羧基的位置不同对阻垢作用的影响不同. 将静态阻垢的实验结果与分子动力学模拟结果进行了相关性分析, 发现阻垢剂在(104)面和(102)面上的吸附对阻垢作用的贡献较大.     

衣康酸-天冬氨酸共聚物合成及其阻垢性能的研究

针对目前国内使用的阻垢剂存在难降解、易造成水体富营养化等问题,以衣康酸(IA)、天冬氨酸(ASP)为单体,过硫酸铵为引发剂,采用水溶液自由基聚合法合成了可生物降解的IA-ASP二元共聚物,并对产物结构进行红外表征。探讨单体配比、引发剂用量、聚合温度、反应时间对共聚物阻垢性能的影响,通过正交实验和单因素实验确定最佳合成条件。采用静态阻垢法考察阻垢剂用量、阻垢实验温度对阻碳酸钙垢性能的影响,并借助扫描电镜观察碳酸钙垢的晶体形貌,探讨其阻垢机理。结果表明:共聚单体的物质的量比(n_(IA)∶n_(ASP))为4∶1,引发剂用量为单体总质量的9%,反应温度85℃,反应时间2 h时,合成的IA-ASP共聚物对碳酸钙的阻垢率可达95%以上。IA-ASP共聚物作为阻垢剂适用于中低水温环境,其阻垢率随阻垢剂用量增加逐渐提高,最终趋于平缓。IA-ASP共聚物阻垢机理主要涉及螯合、分散作用及晶格畸变。     

衣康酸-天冬氨酸-苯乙烯磺酸钠三元共聚物的合成及阻垢性能研究

以衣康酸(IA)、天冬氨酸(ASP)及苯乙烯磺酸钠(SSS)为单体,过硫酸铵为引发剂,采用水溶液自由基聚合法合成了IA-ASP-SSS三元共聚物,并对产物结构进行红外表征。探讨单体配比、引发剂用量、聚合温度、反应时间对共聚物阻垢性能的影响,通过正交实验和单因素实验确定最佳合成条件。采用静态阻垢法考察阻垢剂用量、钙离子浓度对阻垢性能的影响。结果表明,共聚单体的摩尔比(nASP∶nIA∶nSSS)为1∶1∶0.1、引发剂用量为单体总质量的9%、反应温度85℃且反应时间3h时,合成的IA-ASP-SSS共聚物对碳酸钙、磷酸钙及硫酸钙的阻垢率皆在95%以上,且此共聚物阻垢剂适用于高硬度水环境。     

衣康酸-天冬氨酸-苯乙烯磺酸钠三元共聚物合成及阻垢性能研究

以衣康酸(IA)、天冬氨酸(ASP)及苯乙烯磺酸钠(SSS)为单体,过硫酸铵为引发剂,采用水溶液自由基聚合法合成了IA-ASP-SSS三元共聚物,并对产物结构进行红外表征。探讨单体配比、引发剂用量、聚合温度、反应时间对共聚物阻垢性能的影响,通过正交实验和单因素实验确定最佳合成条件。采用静态阻垢法考察阻垢剂用量、钙离子浓度对阻垢性能的影响。结果表明：共聚单体的物质的量比(nASP:nIA:nSSS)为1:1:0.1、引发剂用量为单体总质量的9%、反应温度85℃且反应时间3h时,合成的IA-ASP-SSS共聚物对碳酸钙、磷酸钙及硫酸钙的阻垢率皆在95%以上,且此共聚物阻垢剂适用于高硬度水环境。     

N-氨基甲酰马来酸接枝聚天冬氨酸聚合物的合成及其阻垢性能研究

以聚琥珀酰亚胺(PSI)和N-氨基甲酰马来酸为原料,合成N-氨基甲酰马来酸接枝聚天冬氨酸聚合物(PASP-NCA)阻垢剂.通过红外光谱和核磁共振氢谱对PASP-NCA结构进行表征.采用静态阻垢法评价该阻垢剂的阻CaCO3垢性能.通过扫描电子显微镜探讨CaCO3垢晶体形貌的变化.结果表明,相对于纯聚天冬氨酸(PASP),...     

Scale inhibition study by turbidity measurement

The concept of a critical supersaturation ratio (CSSR) has been used to characterize the effectiveness of different types of scale inhibitors, inhibitor concentration, and precipitating solution pH in order to prevent the formation of barium sulfate scale. The scale inhibitors used in this work were aminotrimethylene phosphonic acid (ATMP), diethylenetriaminepentamethylene phosphonic acid (DTPMP), and phosphinopolycarboxylic acid polymer (PPCA). The CSSR at which barium sulfate precipitates was obtained as a function of time for different precipitation conditions and was used as an index to evaluate the effect of the precipitation conditions. The results showed that the CSSRs decrease with increasing elapsed time after mixing the precipitating solutions, but increases with increasing scale inhibitor concentration and solution pH. The CSSR varies linearly with the log of the scale inhibitor concentration and with the precipitating solution pH. A SEM analysis showed that the higher the scale inhibitor concentration and solution pH, the smaller and more spherical the BaSO4 precipitates. Analysis of the particle size distribution revealed that increasing the elapsed time, the scale inhibitor concentration, and precipitating solution pH, all produce a broader particle size distribution and a smaller mean diameter of the BaSO4 precipitates. DTPMP and PPCA were the most effective BaSO4 scale inhibitors per ionizable proton and the most effective on a concentration basis, respectively.     

Investigation of scale inhibition mechanisms based on the effect of scale inhibitor on calcium carbonate crystal forms

To probe the scale inhibition mechanisms,calcium carbonate scale occurring before and after the ad- dition of scale inhibitors was collected.The results from scale SEM confirm that,without scale inhibitor, calcium carbonate scale shows rhombohedron and hexagon,which are the characteristic feathers of calcite.After addition of inhibitors,morphology of scale is changed,and the more efficient the scale inhibitor is,the more greatly the morphology is modified.To elucidate the scale constitute,they were further analyzed by FT-IR,XRD.Besides calcite,vaterite and aragonite occur in calcium carbonate scale after addition of inhibitors,and the higher scale inhibition efficiency is,the more vaterite presents in scale.It can be concluded that the alteration of morphology is ascribed to the change of crystal form. There are three stages in the crystallizing process including occurrence and disappearing of unstable phase,occurrence and disappearing of metastable phase,development of stable phase.Without scale inhibitors,metastable phases usually transform into stable phase,thus the main constitute of formed scale is calcite.When scale inhibitors are added,both formation and transformation of metastable phases are inhibited,which results in the occurrence of aragonite and vaterite.From the fact that more vaterite presents in scale with a more efficient scale inhibitor added,we can see that the function of scale inhibitor is realized mainly by controlling the crystallizing process at the second stage.     

聚醚型无磷共聚物的合成及其阻垢性能

以水为溶剂,丙烯酸(AA)和烯丙氧基聚醚羧酸钠(APEX)为单体,合成了一种新型的无磷聚醚共聚物(APEX/AA)。 通过红外光谱、热重分析及凝胶渗透色谱对聚合物进行了表征。 通过静态法评价了APEX/AA用量、溶液钙离子浓度、pH值、温度对APEX/AA阻磷酸钙垢率的影响。 结果表明,聚合物APEX/AA有良好的热稳定性（至350 ℃才明显失重）,相对分子质量分布可控(PDI=1.41~1.88)。 APEX/AA在用量6 mg/L时阻磷酸钙垢率达到100%,APEX/AA阻磷酸钙垢效果优于羟基亚乙基二膦酸、丙烯酸/丙烯酸羟丙酯、2-膦酸丁烷-1,2,4-三羧酸等商业阻垢剂,适用于高钙（Ca2+浓度200~2000 mg/L）、高pH值（7.5~11.0）和高温（75~95 ℃）水质,是一种工业循环水系统中性能优良的阻磷酸钙垢无磷阻垢剂。     

Study of Ca-ATMP precipitation in the presence of magnesium ion

ATMP (aminotri(methylenephosphonic acid)), a phosphonate scale inhibitor used in the petroleum industry, was used as a model scale inhibitor in this study. One of the goals of this work was to determine the range of conditions under which Mg ions, which are formed in reservoir formations containing dolomite, modulate the formation of Ca-ATMP precipitate as a scale inhibitor. The results revealed that the amount of ATMP precipitated decreased with addition of Mg ions in solution at all values of the solution pH. Furthermore, an increase in both the solution pH and the concentration of the divalent cations in solution resulted in a change of the molar ratio of (Ca + Mg) to ATMP in the precipitates. At a low solution pH (pH 1.5), Mg ions had little effect on the composition of the Ca-ATMP precipitate. However, at higher values of the solution pH (pH 4 and 7), the Ca to ATMP molar ratio in the precipitates decreased with increasing concentration of the Mg. Here it was found that Mg ions replaced Ca ions on available reactive sites of ATMP molecules. These results determined the limits of the Mg ion concentration, which affects the precipitation of Ca-ATMP, Mg-ATMP, and (Ca + Mg)-ATMP. The dissolution of the scale inhibitors was studied using a rotating disk reactor. These experiments showed that the total divalent cation molar ratio (Ca + Mg) to ATMP in the precipitates is the primary factor that controls the rate of dissolution (release) of the phosphonate precipitates. The phosphonate precipitate dissolution rates decreased as the molar ratio of divalent cations to ATMP in the precipitates increased.     

PHASE BEHAVIOUR OF PHOSPHINOPOLYACRYLATE SCALES INHIBITOR

The influence of the Ca⁺⁺ and inhibitor concentrations, pH, and temperature on the phase behaviour and precipitation yield of a phosphinopolyacrylate scale inhibitor, PPAA, has been studied. The results are interpreted in terms of the chemical processes governing PPAA-Ca⁺⁺ complexation, and evidence for the role of inhibitor molecular weight in determining the degree of precipitation is produced. Comparative adsorption and precipitation squeezes, carried out in sandpacks, demonstrate that significant enhancement of the treatment lifetime can be achieved when conditions giving extensive inhibitor precipitation are used. The sandpack experiments and dissolution studies on the precipitated inhibitor both suggest strongly that kinetic phenomena influence the return level of inhibitor in the field. Together these studies point the way to approaches for optimising inhibitor precipitation squeeze treatments in order to control scale deposition in petroleum reservoirs.     

Synthesis of polyaspartic acid-glycidyl adduct and evaluation of its scale inhibition performance and corrosion inhibition capacity for Q235 steel applications

In this work, the development of the eco-friendly comprehensive scale and corrosion inhibitor based on green polyaspartic acid (PASP) was presented. In this view, PASPG was prepared by a ring-opening graft modification reaction of polysuccinimide (PSI) with glycidyl. In addition, the molecular structure and the thermal stability of PASPG were characterized by using three different methods (FTIR, ¹H NMR, and TGA). PASPG’s scale inhibition efficiency and corrosion inhibition efficiency were also evaluated, respectively. More concretely, the scale inhibition efficiency of PASPG achieved 94.6 % and 95.1 % for CaCO₃ and CaSO₄, respectively. With the aid of the FTIR and SEM measurement techniques, it was found that PASPG could induce the irregular growth of the CaCO₃ and CaSO₄ morphology and destroy the formation of crystals. On the other hand, the higher corrosion efficiency of 85.17 % was achieved by PASPG in comparison with PASP (72.53 %). PASPG is a mixed inhibitor and the adsorption of PASPG on the Q235 steel surface followed the Langmuir mono-layer adsorption isotherm. The formation of a protective film on the surface of carbon steel was proved by PASPG’s adsorption, which increased the resistance to be eroded. Thus, the surface of carbon steel can be effectively protected. The present work provides a simple and effective pathway for the synthesis of high-efficiency green scale and corrosion inhibitor, by introducing a functional group into the PASP chains. The implementation of such type of chemical modification method may also be an effective strategy for improving the efficiency of other polymers green scale and corrosion inhibitors.     

Corrosion Inhibition of a Green Scale Inhibitor Polyepoxysuccinic Acid

The corrosion inhibition of a green scale inhibitor, polyepoxysuccinic acid (PESA) was studied based on dynamic tests. It is found that when PESA is used alone, it had good corrosion inhibition. So, PESA should be included in the category of corrosion inhibitors. It is not only a kind of green scale inhibitor, but also a green corrosion inhibitor. The synergistic effect betweenPESA and Zn2 or sodium gluconate is poor. However, the synergistic effect among PESA, Zn2 and sodium gluconate is excellent, and the corrosion inhibition efficiency for carbon steel is higher than 99%. Further study of corrosion inhibition mechanism reveals that corrosion inhibition of PESA is not affected by carboxyl group, but by the oxygen atom inserted. The existence of oxygen atom in PESA molecular structure makes it easy to form stable chelate with pentacyclic     

Scale formation and control in oil and gas fields: A review

The formation of scale poses several serious menaces in oil and gas exploitations. The scaling phenomenon may cause technical problems such as obstruction of equipment and pipes, which causes great damages and results in economic losses; besides, scale is one of the most difficult issues to resolve. Preventing scale formation relies on understanding the composition of the scale, appropriate scale inhibitor, and early pretreatment. The use of chemicals acting as a scale inhibitor is a significantly effective and economical approach in controlling scale deposition. This review mainly studies the mechanism of scale formation, the characteristics of different kinds of scale inhibitors, and the progress of application research in recent years. In particular, some of the green scale inhibitors derived from synthetics and “natural” organic molecules are summed up. Meanwhile, the prospects of scale inhibitors in the future are also described. It is hoped that this review will have potential value for the development of an efficient, economic, and environment-friendly scale inhibitor.     

Review of corrosive environments for copper and its corrosion inhibitors

This review paper deals with corrosion of copper and its alloys in corrosive environments and their corrosion inhibitors. The main corrosion inhibitor groups for copper are introduced and a review of adsorption models is provided. The main part of this work is to investigate different corrosive environments for copper and its alloys and their corrosion inhibitors used in such environments to protect copper. According to the literature, the corrosion inhibition behavior of organic corrosion inhibitors and their derivatives in comparison with inorganic ones are further evaluated. Knowing maximum corrosion inhibition efficiency of a specific corrosion inhibitor in a specific corrosive environment is helpful to choose the most appropriate corrosion inhibitor compound.