将改进的无相态影响时电解质溶液中无机盐结垢量预测模型与其他预测方法进行了对比验证。同时采用自研的高温、高压地层流体结垢测试实验装置,测试了实际气藏流体的无机盐结垢量,并对文章(I)中提出的含水气藏多相平衡结垢预测模型进行了实例验证和应用。结果表明,实际气藏流体的无机盐结垢量随压力的降低而增加,模型预测和实验测试结果一致。考虑相态影响的结垢预测新模型可准确预测实际气藏流体在多相平衡条件下的流体相态变化和无机盐结垢量,预测结果平均偏差约2%。而不考虑相态变化影响的模型预测结垢量明显低于实验测试结果,平均偏差约15%,且随压力的降低差值不断增加。生产过程中随气藏压力降低,在油气相态影响下地层水蒸发加剧,导致地层水离子浓度增加,若不考虑流体相态变化的影响将导致无机盐结垢预测量明显偏低。图5表6参20
The prediction results by the scaling model without the influence of phases proposed in previous article was contracted with other models. The scaling test of real gas field fluid was carried out using the scaling test equipment under the condition of high temperature and high pressure, through which the new scaling prediction model considering multiph~se equilibrium for gas field containing water was tested and verified. The results showed that the amount of scale buildup of real reservoir fluid increased with decreasing pressure. The results predicted by model and that tested by laboratory experiment were accordant. The new method could accurately predict the amount of scale of gas field fluid under multiphase equilibrium, and the average deviation was about 2%. If the influence of phase behavior change was not considered, the average deviation of predicted scaling amount from experiment results was about 15%, and the deviation increased with decreasing pressure. During the production, the evaporation of water under the influence of oil and gas phase behavior intensified with decreasing reservoir pressure, which caused the concentration of ions in formation water to increase. If phase behavior changes of reservoir fluid were not considered, the predicted amount of scale would be lower obviously.