Development and performance evaluation of novel soluble wax removal ball for oil transportation pipelines

• 1、College of Chemistry and Chemical Engineering, Xi’an Shiyou University, Xi’an 710065, China

Abstract：In view of the shortcomings of traditional wax cleaner balls in terms of single function, insolubility and high risks of ball jamming and wax blocking, a soluble wax removal ball with both physical wax removal function and chemical wax inhibiting effect was designed and prepared for oilfield gathering system. The static wax prevention rate and dynamic wax prevention rate of the selected anti-wax agent were tested using the hanging method and the homemade dynamic wax prevention rate testing device, and the indoor physical performance and dissolution performance of the wax removal ball were evaluated by the press and the homemade indoor dynamic dissolution simulation device, and finally the field test was conducted. The results of the wax inhibiting rate test show that the wax inhibiting rate of the anti-wax agent can reach up to 50% and the effect is more obvious when applied to the actual situation. The results of the physical performance test show that the pressure-bearing capacity of the wax spheres of different formulations made is above 2 MPa and will not be broken when running in the pipeline, thus realizing the role of physical wax removal. The results of the dynamic dissolution and release performance of the anti-wax components in the wax spheres show that the dissolution and release rate of the wax spheres gradually increases with the rise of temperature. The test results show that the dissolution and release rate of the wax inhibiting component in the wax removal ball gradually increases with the rise of temperature while gradually decreases with the increase of water content. In addition, as the content of the wax inhibiting agent in the wax inhibiting component increases, the dissolution and release rate shows a decreasing trend. The dissolution and release rate of the wax inhibiting component varies under different conditions, with the highest being 0.28 g/h and the lowest being 0.08 g/h, and the release rate is low and controllable, which can meet the demand of wax inhibiting in different pipelines. It can be slowly released in the crude oil during the dynamic dissolution process of pipeline to play the role of long-lasting chemical wax inhibiting, and the release rate will change with different formulations to realize the control over the release rate. The improved performance has been verified by field application test.

Keywords： soluble wax removal ball physical wax removal chemical wax inhibiting release rate field application