Inhibition effect and mechanism of corrosion inhibitor at oil-water interface region
-
摘要: 利用旋轉圓柱電極，結合電化學方法（電化學交流阻抗、極化曲線）、激光掃描共聚焦顯微鏡、掃描電子顯微鏡和紫外-可見分光光度法研究了流動工況下油水分層介質中緩蝕劑在油水兩相界面處的作用效果及機理。結果表明，該工況下，100 mg·L?1十七烯基胺乙基咪唑啉季銨鹽緩蝕劑對碳鋼在油水兩相分層介質中的水區具有良好的緩蝕效果，緩蝕效率高達99%，但在油水兩相界面區域，由于油相的大量存在，導致緩蝕劑的有效質量分數降為混合前的31%，緩蝕效率僅為83%，緩蝕效果較差，碳鋼腐蝕未得到有效抑制，甚至出現了溝槽腐蝕。因此，在油區試樣腐蝕輕微，并且緩蝕劑的加入有效抑制了水區X65鋼的腐蝕。Abstract: With the development of offshore oil and gas fields, the oil–water two-phase mixing flow-transmission technology has been widely used in subsea pipelines. The high water cut and multiphase flow regime induce harsh and complex corrosion conditions; hence, mild steels combined with corrosion inhibitors are used in the construction of offshore pipelines for corrosion control. However, corrosion failure cases show that severe localized corrosion constantly occurs at the oil–water interface in oil–water mixed transmission pipelines, and the understanding of the mechanism and inhibition effect of corrosion inhibitors is limited. Moreover, laboratory studies on CO2 corrosion problems in oil–water mixed transmission pipelines usually consider only pure-water systems to simulate the corrosive environment. These studies seldom regard the effect of the oil phase on the corrosion process even though the actual production and transportation of fluids often involves multiphase mixed media. The oil phase is one of the important factors that affect corrosion behavior. Studies on the impact of the oil phase on the inhibition effect of corrosion inhibitor are still relatively lacking. Further studies on the inhibition effect of corrosion inhibitor in oily corrosive environments of oil–water mixed transmission pipelines are needed. In this study, the inhibition effect and mechanism of a corrosion inhibitor at the oil–water two-phase interface under flow conditions were investigated using the rotating cylindrical electrode (RCE) technique combined with electrochemical methods (electrochemical impedance spectroscopy and polarization curve analysis), laser scanning confocal microscopy, scanning electron microscopy, and UV-VIS spectrophotometry. The results reveal that 100 mg·L?1 of seventeen alkenyl amide ethyl imidazoline quaternary ammonium salt as a corrosion inhibitor in carbon steel for an aqueous phase of the oil–water two-phase stratified medium exhibits significant inhibition effect, and the corrosion inhibition efficiency reachs 99%. However, the effective mass fraction of the corrosion inhibitor decreases to 31% before mixing at the oil–water interface because of the presence of oil. As a result, the corrosion inhibition efficiency is only 83%, and the inhibition effect is poor; moreover, the corrosion of carbon steels cannot be effectively controlled. Further, significant groove corrosion is observed at the oil–water interface. Therefore, the corrosion of the sample in the oil area is slight, and the inhibitor can effectively inhibit the corrosion of X65 steel in the water area.
-
Key words:
- carbon steel /
- rotating cylinder electrode /
- CO2 corrosion /
- oil–water interface /
- corrosion inhibitor
-
圖 1 十七烯基胺乙基咪唑啉季銨鹽的結構
Figure 1. Structure of seventeen alkenyl amide ethyl imidazoline quaternary ammonium salt
圖 3 X65鋼在油水分層介質中的電化學測試結果. （a） 動電位極化曲線; （b） 陽極脫附平臺; （c） 腐蝕速率; （d） 緩蝕效率
Figure 3. Electrochemical test results of X65 steel in oil–water stratified medium: (a) potentiodynamic polarization curve; (b) anode desorption platform; (c) corrosion rate; (d) corrosion inhibition efficiency
圖 4 X65鋼在油水分層介質不同區域中的交流阻抗譜. （a） 水區, 0; （b） 水區, 100 mg·L?1; （c） 耦合, 0; （d） 耦合, 100 mg·L?1
Figure 4. EIS results of X65 steel measured at different areas of oil–water stratified medium: (a) in water region, 0; (b) in water region, 100 mg·L?1; (c) coupled, 0; (d) coupled, 100 mg·L?1
圖 5 EIS等效電路圖. （a） 單容抗；（b） 雙容抗；（c） 容抗 + 感抗 + 容抗
Figure 5. Equivalent circuit used for fitting the EIS results: (a) single capacitive reactance; (b) double capacitive reactance; (c) capacitive reactance + inductive reactance + capacitive reactance
圖 7 X65鋼在油水分層介質中浸泡24 h后的腐蝕形貌. （a） 未加OAI酸洗前; （b） 未加OAI酸洗后; （c） 加OAI酸洗前; （d） 加OAI酸洗后; （e） 激光共聚焦三維形貌
Figure 7. Corrosion morphology of X65 steel in oil–water stratified medium after immersion for 24 h: (a) before pickling without OAI; (b) after pickling without OAI; (c) before pickling with OAI; (d) after pickling with OAI; (e) 3D profile of microcorrosion morphologies
圖 8 紫外可見分光光度計測試結果。（a） 純水相；（b） 油水分配后；（c） 特征峰吸光度
Figure 8. Test results of ultraviolet visible spectrophotometer: (a) in aqueous phase; (b) after oil and water partition; (c) characteristic peak absorbance
圖 9 十七烯基胺乙基咪唑啉季銨鹽緩蝕劑在油水兩相分層介質不同區域中的作用機理. （a） 水區; （b） 兩相界面處; （c） 油區
Figure 9. Schematic diagram of mechanism of seventeen alkenyl amide ethyl imidazoline quaternary ammonium salt in different zones of oil–water stratified medium: (a) in water region; (b) at the oil–water interface; (c) in oil region
表 1 實驗用X65鋼的化學成分（質量分數）
Table 1. Chemical composition of the X65 steel
% C Si Mn P Mo S Fe 0.040 0.200 1.500 0.011 0.020 0.003 余量 
下載: 導出CSV
表 2 油田地層水采出液的組分
Table 2. Composition of the test solution simulating the oilfield formation water
mg·L?1 Na+ Mg2+ Ca2+ K+ Cl－ ${\rm{SO}}_4^{2 - }$ ${\rm{HCO}}_3^ - $ 26231 1920 2747 644 35297 197 519
下載: 導出CSV
表 3 等效電路各參數值
Table 3. Parameter values of the equivalent circuit
介質 質量濃度/
(mg·L?1)時間/h Rs/(Ω·cm2) CPEf Rf/Ω CPEdl Rct/(Ω·cm2) RL/(Ω·cm2) L/H ${Y_1}/({\rm{S}} \cdot {{\rm{s}}^{{n_1}}} \cdot {\rm{c}}{{\rm{m}}^{ - 2}})$ n1 ${Y_2}/({\rm{S}} \cdot {{\rm{s}}^{{n_2}}} \cdot {\rm{c}}{{\rm{m}}^{ - 2}})$ n2 水區 0 2 11.38 — — — 9.07 0.800 78.44 — — 6 8.19 — — — 13.43 0.789 87.22 — — 24 39.14 1384 0.89 60.70 1860 0.966 22.51 — — 水區 100 2 0.01 0.001 0.615 331 224.90 1218 6 10.98 37.32 0.67 1398 139.70 0.857 818.90 8641 14370 24 26.93 143.90 0.53 1926 353.40 1 1058 3751 1049 耦合 0 2 2.72 — — — 14.96 0.778 40.40 — — 6 27.52 — — — 19.14 0.800 43.85 — — 24 3.35 2793 0.86 24.47 9699 0.973 5.98 — — 耦合 100 2 3.19 6.51 0.750 231.40 6 1.00 1268 0.35 33.80 0.61 0.981 344.50 518.80 193.20 24 0.04 752.20 0.44 80.71 0.71 0.924 364.90 1315 631.80
下載: 導出CSV
259luxu-164<th id="5nh9l"></th> <strike id="5nh9l"></strike> <th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th> <strike id="5nh9l"></strike> <th id="5nh9l"><noframes id="5nh9l"> <th id="5nh9l"></th> <strike id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span> <span id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span> <strike id="5nh9l"><noframes id="5nh9l"><strike id="5nh9l"></strike> <span id="5nh9l"><noframes id="5nh9l"> <span id="5nh9l"><noframes id="5nh9l"> <span id="5nh9l"></span> <span id="5nh9l"><video id="5nh9l"></video></span> <th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th> -
參考文獻
[1] Wang H W, Hong T, Cai J Y, et al. Enhanced mass transfer and wall shear stress in multiphase slow flow // Corrosion 2002. Denver, 2002: 02501 [2] Cai J Y, Nesic S, de Waard C. Modeling of water wetting in oil-water pipe flow // Corrosion 2004. New Orleans, 2004: 04663 [3] Lu M X, Bai Z Q, Zhao X W, et al. Actuality and typical cases for corrosion in the process of extraction, gathering, storage and transmission for oil and gas. Corros Prot, 2002, 23(3): 105 doi: 10.3969/j.issn.1005-748X.2002.03.005路民旭, 白真權, 趙新偉, 等. 油氣采集儲運中的腐蝕現狀及典型案例. 腐蝕與防護, 2002, 23(3):105 doi: 10.3969/j.issn.1005-748X.2002.03.005 [4] Palacios C A, Shadley J R. CO2 corrosion of N-80 steel at 71 ℃ in a two-phase flow system. Corrosion, 1993, 49(8): 686 doi: 10.5006/1.3316101 [5] Kang C, Gopal M, Jepson W P. Localized corrosion in multiphase pipelines // Corrosion 2004. New Orleans, 2004: 04381 [6] Li Z L, Cheng Y F, Bi H S, et al. Research progress of CO2/H2S corrosion and inhibitor techniques in oil and gas fields. CIESC J, 2014, 65(2): 406 doi: 10.3969/j.issn.0438-1157.2014.02.006李自力, 程遠鵬, 畢海勝, 等. 油氣田CO2/H2S共存腐蝕與緩蝕技術研究進展. 化工學報, 2014, 65(2):406 doi: 10.3969/j.issn.0438-1157.2014.02.006 [7] Nesic S, Wang S H, Cai J Y, et al. Integrated CO2 corrosion-multiphase flow model // SPE International Symposium on Oilfield Corrosion. Aberdeen, 2004: SPE-87555-MS [8] Zhang J X, Kang J, Fan J C, et al. Study on erosion wear of fracturing pipeline under the action of multiphase flow in oil & gas industry. J Nat Gas Sci Eng, 2016, 32: 334 doi: 10.1016/j.jngse.2016.04.056 [9] Cheng Y P, Bai Y, Li Z L, et al. Corrosion characteristics of X65 steel in CO2/oil /water environment of gathering pipeline. Chin J Eng, 2018, 40(5): 594程遠鵬, 白羽, 李自力, 等. 集輸管道CO2/油/水環境中X65鋼的腐蝕特征. 工程科學學報, 2018, 40(5):594 [10] Goyal M, Kumar S, Bahadur I, et al. Organic corrosion inhibitors for industrial cleaning of ferrous and non-ferrous metals in acidic solutions: a review. J Molecular Liquids, 2018, 256: 565 doi: 10.1016/j.molliq.2018.02.045 [11] Choi H, Tonsuwannarat T. Unique roles of hydrocarbons in flow-induced sweet corrosion of X-52 carbon steel in wet gas condensate producing wells // Corrosion 2002. Denver, 2002: 02559 [12] Choi H J. Effect of liquid hydrocarbons on flow-induced sweet corrosion of carbon steel // Corrosion 2004. New Orleans, 2004: 04664 [13] Liu X W, Zheng J S. Effects of a small amount of diesel fuel oil on corrosion of carbon steel in brine medium. Mater Prot, 1999, 32(1): 1 doi: 10.3969/j.issn.1001-1560.1999.01.001劉小武, 鄭家燊. 少量柴油對鹽水介質中碳鋼腐蝕的影響. 材料保護, 1999, 32(1):1 doi: 10.3969/j.issn.1001-1560.1999.01.001 [14] Liu X W, Peng F M, Yu D Y, et al. Corrosion inhibitor for oil pipeline. Mater Prot, 2000, 33(8): 3 doi: 10.3969/j.issn.1001-1560.2000.08.002劉小武, 彭芳明, 俞敦義, 等. 輸油管線緩蝕劑的研究. 材料保護, 2000, 33(8):3 doi: 10.3969/j.issn.1001-1560.2000.08.002 [15] Zhao J M, Li Y L, Gu F, et al. Influence of crude oil on inhibition performance of corrosion inhibitors in H2S/CO2 containing brines. Corros Sci Prot Technol, 2016, 28(5): 423趙景茂, 李玉龍, 谷豐, 等. H2S/CO2腐蝕環境中原油對緩蝕劑緩蝕性能的影響. 腐蝕科學與防護技術, 2016, 28(5):423 [16] Liu L W, Zhao X R, Hu Q. Study on corrosion inhibiting efficiency of imidazoline corrosion inhibitor in oil-water coexistence condition. Oil-Gasfield Surf Eng, 2001, 20(1): 25 doi: 10.3969/j.issn.1006-6896.2001.01.015劉烈煒, 趙小蓉, 胡倩. 油水兩相共存下咪唑啉緩蝕劑的緩蝕效率. 油氣田地面工程, 2001, 20(1):25 doi: 10.3969/j.issn.1006-6896.2001.01.015 -
點擊查看大圖
計量
- 文章訪問數: 1737
- HTML全文瀏覽量: 1120
- PDF下載量: 59
- 被引次數: 0
