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 between PESA 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 structure.

An Eco-Friendly High-Effective Scale Inhibitor for High Salt Brine

Now the mining of high salt underground brine has been an important aspect of salt lake mining,which is the necessary support to the development of national economy.With the change of underground geological

The Preparation and Performance Study of a Phosphate-Free Corrosion/Scale Inhibitor

By using acrylic acid copolymer, sodium citrate, hydrolyzed polymaleic anhydride (HPMA), corrosion inhibitor D and Zn2+ synergist as raw materials, a multi-component phosphate-free corrosion and scale inhibitor was developed. The performance of the composite phosphate-free corrosion and scale inhibitor was evaluated using the rotary hanging sheet corrosion test, the static scale inhibition test and the corrosion electrochemical test. And the surface morphology of the carbon steel was observed by scanning electronic microscope (SEM). Orthogonal experiment results indicated that the optimal mass ratios of amino acid: Zn2+ synergist: HPMA: corrosion inhibitor D: acrylic acid copolymer was 0.5:10:12:1:8. It was also observed that phosphate-free corrosion and scale inhibitor based on an anodic reaction through the electrochemical corrosion experiment, its annual corrosion rate and scale inhibition rate reached 0.0176 mm·a–1 and 98.3%, respectively, showing excellent corrosion and scale inhibition performance.

Experimental Study on a New Corrosion and Scale Inhibitor

The mixture consisted of benzotriazole (BTA), chitosan (CTS), polyacrylic acid and zinc salt has been investigated as a corrosion and scale inhibitor of A3 carbon steel in cooling water. The scale and corrosion inhibition efficiency was evaluated by static anti-scaling teat together with rotary coupon test. Compared with the phosphorus corrosion and scale inhibitor, the corrosion inhibition rate and scale inhibition rate of it increased respectively by 2.51% and 1.16%. As the corrosion and scale inhibitor is phosphate-free, it won’t cause eutrophication, considering the product performance and environmental influence, the phosphate-free corrosion and scale inhibitor is superior to the traditional one.

State of the art of synthetic threshold scale inhibitors for mineral scaling in the petroleum industry: a review

Inorganic scale deposits are a major water-related problem encountered in producing oil and gas wells. The harshness of scale deposits is dependent on the field operating conditions. Scale deposits can vary from mild scaling tendencies to extreme. In general, the scale deposit will cause a reduction in formation pores, declining productivity and eventually blockage of the wellbore and hence unexpected downtime if it is allowed to persevere. To overcome this, the productivity of an oil and gas well is ensured by handling scale deposits via removal or prevention methods. Scale prevention is the best and cost-e ective method for handling scale deposits that ensures production continuity. Inhibition through 'threshold' scale inhibitor treatment is the most common method that is proven to prevent or reduce likely deposits. This paper examines the art of synthetic scale inhibitors, in particular, threshold scale inhibitors in oil and gas production. It discusses the chemistry of those inhibitors, inhibition mechanisms, treatment methods and key properties for their applications. It also highlights the chemistry of the synthetic routes often used to produce them in the laboratory and/or industry. Finally, it highlights the environmental concerns for the applicability of threshold scale inhibitors.

Fabrication of a silane-modified superhydrophobic TiO_(2)-PVDF-FEP coating with scale inhibition performance

Titanium dioxide(TiO_(2))whiskers modified with octadecyltrimethoxysilane were incorporated into the coating solution through a solution blending method.The superhydrophobic coating was designed and fabricated using polyvinylidene fluoride(PVDF)and polyperfluorinated ethylene propylene(FEP)as the main constituents,while silane-modified TiO_(2) whiskers as the fillers.The results demonstrated that after a 360-h scaling test,the mass of CacO_(3) on the surface of the resulted silane-modified superhydrophobic TiO_(2)-PVDF-FEP coating was only 1.90 mg·cm^(-2),decreased by 37.1%and 16.7%compared with those on the PVDF-FEP coating and the TiO_(2)-PVDF-FEP coating,respectively.The synergistic effects of the air film,silane-modified TiO_(2) whiskers,and superhydrophobicity ensure that this superhydrophobic TiO_(2) PVDF-FEP coating has excellent scale inhibition performance.This study presents a novel approach for advancing the development of superhydrophobic coatings,offering promising prospects for industrial-scale applications in preventive measures.

Effect of six kinds of scale inhibitors on calcium carbonate precipitation in high salinity wastewater at high temperatures

Precipitation of calcium carbonate （CaCOs） scale on heat transfer surfaces is a serious and expensive problem widely occurring in numerous industrial processes. In this study, we compared the scale inhibition effect of six kinds of commercial scale inhibitors and screened out the best one （scale inhibitor SQ-1211） to investigate its scale inhibition performance in highly saline conditions at high temperature through static scale inhibition tests. The influences of scale inhibitor dosage, temperature, heating time and pH on the inhibition efficiency of the optimal scale inhibitor were investigated. The morphologies and crystal structures of the precipitates were characterized by Scanning Electron Microscopy and X-ray Diffraction analysis. Results showed that the scale inhibition efficiency of the optimal scale inhibitor decreased with the increase of the reaction temperature. When the concentration of Ca^2＋ was 1600 mg/L, the scale inhibition rate could reach 90.7% at 80℃ at pH 8. The optimal scale inhibitor could effectively retard scaling at high temperature. In the presence of the optimal scale inhibitor, the main crystal structure of CaCOs changed from calcite to aragonite.

New insight into scale inhibition during tea brewing: Ca^(2+)/Mg^(2+) complexing and alkalinity consumption

Scale not only affects the taste and color ofwater,but also increases the risks of osteoporosis and cardiovascular diseases associated with drinking it.As a popular beverage,tea is rich many substances that have considerable potential for scale inhibition,including protein,tea polyphenols and organic acids.In this study,the effect of tea brewing on scale formationwas explored.It was found that the proteins,catechins and organic acids in tea leaves could be released when the green tea was brewed in water with sufficient hardness and alkalinity.The tea-released protein was able to provide carboxyl groups to chelate with calcium ions(Ca^(2+)),preventing the Ca^(2+)from reacting with the carbonate ions(CO_(3)^(2-)).The B rings of catechins were another important structure in the complexation of Ca^(2+)and magnesium ions(Mg2+).The carboxyl and hydroxyl groups on the organic acids was able to form fivemembered chelating rings with Ca^(2+)and Mg^(2+),resulting in a significant decrease in Ca^(2+)from 100.0 to 60.0 mg/L.Additionally,the hydrogen ions(H^(+))provided by the organic acids consumed and decreased the alkalinity of the water from 250.0 to 131.4 mg/L,leading to a remarkable reduction in pH from 8.93 to 7.73.It further prevented the bicarbonate(HCO_(3)^(-))from producing CO_(3)^(2−)when the water was heated.The reaction of the tea constituents with the hardness and alkalinity inhibited the formation of scale,leading to a significant decrease in turbidity from 10.6 to 1.4 NTU.Overall,this study provides information to help build towards an understanding of the scale inhibition properties of tea and the prospects of tea for anti-scaling in industrial applications.

Synergistic scale inhibition of polyaspartic acid composite with magnetic field

Polyaspartic acid(PASP)composite,a scale inhibitor,was prepared from PASP,itaconic acid—acrylic acid—acrylic ester(IA-AA-AE)terpolymer and 2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA).The scale inhibition of PASP composite and the effect of its synergism with a magnetic field on scale inhibition were investigated.Calcium carbonate crystals in scale samples were characterized by means of SEM and XRD.The static and dynamic experiments show that the chelating function of PASP composite for Ca2+can be enhanced by synergism with a magnetic field.Under Ca2+650 mg/L,HCO3-1,300 mg/L and PASPcomposite 4 mg/L,the scale inhibition rate of PASP composite in magnetic water can increase by 10%in static state and by 20%in dynamic experiments.Scanning electron microscope(SEM)and X-ray diffraction(XRD)results show that calcite and aragonite can be completely transformed into vaterite by using PASP composite.

Experimental study on the compatibility of scale inhibitors with Mono Ethylene Glycol

When both of the scaling and hydrate risks occur in deep water wells or subsea pipelines at the same time,the compatibility between scale and hydrate inhibitors should be paid more attention to for the risk prevention.In this paper,a new deep-water gas field found in the South China Sea is taken as a reference of project background to investigate the compati bility between scale inhibitors and hydrate inhibitors experimentally.Firstly a preliminary qualification evaluation of scale inhibitors was caried out,in which the static scale inhibition eficiency,the scale induction time,and the minimum effective concentrations of the selected scale inhibitors were tested.Then the effect of commonly used thermodynamic hydrate inhibitor MEG(Mono Ethylene Glycol)on the anti-scaling performance of scale inhibitors was evaluated.MEG-resisted scale inhibitors were further optimized.Finally,an extended discussion on the compati-bility of scale inhibition with hydrate inhibition was conducted.The experimental results showed that the scale inhi bitors HPMA and MA/AA were recommended with the best working concentration of 30 ppm.The high concentration inhibitors(30 wt%)can coexist with the same volume of pure MEG for more than 12-14 h at room condition and 60°C without any precipitation.The anti-scale fficiency of inhibitor with 30 ppm concentration is still up to 90%even at the presence of 20wt%MEG(after2-4 h at 95°C).Hence,in deep-water wellbore,compatible scale and hydrate inhi bitors can be injected together using one chemical pipeline.Besides,it is also found that the polymer scale inhibitors generally have good compatibility with MEG.It deserves further studies and can be regarded as one direction for scale inhibitor improvement in the future.

Experimental study on scale inhibition performance of a green scale inhibitor polyaspartic acid

Static and dynamic experiments were carried out to validate scale inhibition performance of a green scale inhibitor-polyaspartic acid (PASP). From the static experiment, it was shown that below 60°C, polyaspartic acid is very effective in scale inhibition, with the scale inhibition ratio exceeding 90% with only 3 mg/L PASP for the 600 mg/L hardness solution. For a higher hardness solution of 800 mg/L, the scale inhibition ratio can also reach 90% with 6 and 12 mg/L PASP at 30 and 60°C respectively. The SEM photographs of CaCO3 crystals indicate that the crystal structure transforms from a compact stick-shape to a loose shape so that the scale can be washed away easily instead of being deposited on the heat transfer surface. The dynamic experimental results show that almost no scales formed on the heat transfer surface and the fouling thermal resistance decreases extraordinarily if PASP is added in the solution.

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.

环保型水处理药剂在工业循环水中的应用

某化工企业的循环水水质比较复杂,换热管中结垢较严重且已经出现腐蚀现象,严重影响了企业的正常生产。针对这一问题,采用不含磷、氮的原料马来酸(MA)和烯丙基磺酸钠(SAS)合成一种绿色环保型药剂MA/SAS。将其与药剂进行复配,采用静态阻垢实验及旋转挂片实验在企业循环水中测定复配药剂的阻垢性能和缓蚀性能。实验结果表明,该复配药剂应用于该化工企业的循环水系统后,有效抑制了结垢和腐蚀现象的发生,可以满足技术指标要求,为企业带来了一定的经济效益。

Surface lurking and interfacial ion release strategy for fabricating a superhydrophobic coating with scaling inhibition

The design and manufacture of anti-scaling surface is a prospective way to prevent scaling in oil field.In this work,a novel superhydrophobic Cu^(2+)-loaded and DTPMPA-modified anodized copper oxide(S-Cu^(2+)/D-ACO)coating was fabricated by modification of 1H,1H,2H,2H-perfluorodecyltriethoxysilane.The valid storing of scale inhibitors at the coating surface and the interfacial release of Cu^(2+)ions contribute to enhancing the anti-scaling of the S-Cu^(2+)/D-ACO coating.The water contact angle of the S-Cu^(2+)/D-ACO coating is 163.03°and exhibits superhydrophobicity,which makes it difficult for CaCO_(3)to deposit at the surface of the coating.DTPMPA will steadily lurk into the inner space,and Cu^(2+)will be loaded at the interface in the form of the DTPMPA:Cu^(2+)chelate.During the deposition of CaCO_(3),the dynamic release of DTPMPA can be realized by transferring DTPMPA:Cu^(2+)to DTPMPA:Ca^(2+).Interestingly,the released Cu^(2+)hinders the active growth of CaCO_(3).After 48 h of scaling,the mass of CaCO_(3)scale at the S-Cu^(2+)/D-ACO coating surface is only 44.1%that of the anodized copper oxide coating.The excellent anti-scaling performance of the S-Cu^(2+)/D-ACO coating is determined by the synergistic effect of the DTPMPA lurking and dynamic release,as well as the Cu^(2+)inhibition at the interface of superhydrophobic coating and against CaCO_(3)deposition.This research provides a new exploration for designing and fabricating anti-scaling superhydrophobic surface for oil field development.

微生物“清-防-驱”增效解堵体系的性能评价与现场试验

随着油田开发的不断深入,油井堵塞等储层伤害问题愈发严重,导致油井产量下降甚至停产。为有效提高石油开采效率,基于微生物菌体及其代谢产物的协同作用,选用具有解堵和驱油能力的菌株KC(Bacillus subtilis)、DY(Bacillus licheniformis)、DN1(Pseudomonas aeruginosa)及其代谢产物等进行复配而形成具有解堵、阻垢、缓蚀和驱油性能的3种增效解堵体系A、B和C。采用油水界面张力确定菌剂配比,通过垢物溶蚀、CaCO_(3)沉积、静态腐蚀、乳化指数测定和岩心驱替等室内实验进行体系性能评价,并将其用于现场试验。结果表明:增效解堵体系C对有机垢、无机垢和复合垢的溶蚀效率均在80%以上,阻垢率为95.50%,缓蚀率达61.44%,提高驱油效率14.58%。现场试验也证实体系C具有显著的增油效果,2口措施井平均单井日增油0.57 t。

TALOSCALE松垢剂的应用研究

本文通过实验研究了TALOSCALE的防垢机理,并进行了工厂应用研究,研究结果表明,TALOSCALE具有很好的防垢、松垢及除垢效果,提高了蒸发罐的蒸发强度,防垢率高达82.80％,积垢变松软,易于清除,并可代替酸或碱进行煮罐,不损伤加热管表面,使用安全,积垢变薄,疏松易除。

Inhibition of CaCO_3 Scaling in Reverse Osmosis System by Zinc Ion

Scaling of reverse osmosis (RO) membrane surface is one of the main problems in desalination proc- esses. To mitigate scales, organic anti-scalants are often used. If the dosages of anti-scalants are reduced, by using other much cheaper scale inhibitors, RO running cost will decrease greatly. The present paper investigated the inhi- bition of CaCO3 precipitation by zinc ions in RO system. The results show that the zinc ion concentration of 2mg?L-1 was able to exert a marked suppression effect on both bulk precipitation of CaCO3 and on membrane scaling on waters of moderate hardness.

TALOSCALE松垢剂的应用研究

通过实验室及工厂应用研究 ,TAL OSCAL E松垢剂有很好的防垢及松垢除垢效果。提高了蒸发罐的蒸发强度 ,防垢率高达 82 .80 % ,积垢变松软 ,易于清除。可代替酸或碱进行煮罐 ,不损伤加热管表面 ,使用安全 ,积垢变薄 。

绿色水处理药剂的合成及其与静电场协同性能研究

采用不含磷氮的药剂衣康酸(IA)和甲基丙烯磺酸钠(SMAS)合成了环保型的两元共聚物药剂,并系统研究了合成工艺条件对共聚物性能的影响。最终得到最佳合成条件如下:原料质量比(IA∶SMAS)为2∶1,聚合温度为95℃,聚合时间为6 h;此外,引发剂和链转移剂的添加量均为原料总质量的5%。经静态阻垢实验研究表明,合成的共聚物具有优异的阻垢性能和分散性能。将该共聚物与静电场结合用于阻垢性能研究,结果表明静电场的存在使IA/SMAS的阻垢性能提高了17%,静电与IA/SMAS共聚物具有协同增效作用。