弱碱环境中碳酸钙垢阻垢剂的阻垢性能与阻垢机理

Inhibition Performances and Mechanisms of CaCO₃ Scale Inhibitors under Alkalescent Conditions

余吉良 王志坤 霍然 崔延杰 孙霜青 胡松青

YU Jiliang WANG Zhikun HUO Ran CUI Yanjie SUN Shuangqing HU Songqing

为了解决华北油田京11 区块较严重的碳酸钙结垢问题，通过静态阻垢率评价方法研究了聚天冬氨酸（PASP）、聚丙烯酸（PAA）、二乙烯三胺五甲叉膦酸（DTPMP）和羟基乙叉二膦酸（HEDP）在华北油田京11 区块弱碱复合驱环境下的阻碳酸钙垢性能，采用分子动力学模拟从阻垢剂与碳酸钙表面相互作用的角度对其阻垢机理进行了分析。结果表明：4 种阻垢剂对碳酸钙垢的阻垢效果的大小顺序为：HEDP>DTPMP>PAA>PASP。阻垢剂与碳酸钙表面的结合能越大，阻垢剂的阻垢性能越好，结合能的大小顺序与实验测得的阻垢率的大小顺序一致；阻垢剂分子在碳酸钙表面会发生形变，但形变能远小于结合能；阻垢剂在碳酸钙表面吸附时与钙离子和碳酸根离子均存在较强的非键相互作用，非键作用越强，阻垢剂分子的吸附越稳定。图5 表2参20

In order to solve the serious CaCO3 scale problem in Jing11 faulted block in Huabei oilfield，the inhibition performances of sodium of polyaspartic acid（PASP），polyacrylic acid（PAA），diethylenetriamine penta（methylene phosphonic acid）（DTPMP）and 1-hydroxyethylidene-1，1-diphosphonic acid（HEDP）under the alkalescent combination flooding environment were investigated by the static scale inhibition evaluation experiment，and the microscopic scale inhibiton mechanism was analyzed by molecular dynamics simulation of the interaction between the inhibitor and CaCO3 surface. The results showed that the scale inhibition effect of four kinds of scale inhibitors on calcium carbonate scale was as follows，HEDP> DTPMP> PAA> PASP. The inhibition performance was tightly related to the interaction energy between the scale inhibitor and the CaCO3 surface. The larger the interaction energy of the sacle inhibitor on the CaCO3 surface was，the better the scale inhibition performance would be. The sequence of the interaction energies was consistent with that of the inhibition performance. The deformation energies of scale inhibitors on the CaCO3 surface were much smaller than the interaction energies. Strong nonbonded interactions existed between the scale inhibitors and the calcium and carbonate ions. The adsorption of scale inhibitors on the CaCO3 surface will be more stable with stronger non-bonded interactions.

10.19346./j.cnki.1000-4092.2017.04.026