Abstract
The phenomenon of scaling has caused great damage in many industrial production sites, especially in oil and gas field production equipment, and adding scale inhibitors is currently the most effective and commonly used method. However, this method also has the disadvantage of not being able to continuously and effectively remove scale. When there is too little scale inhibitor, it cannot have the effect of scale inhibition, but excessive scale inhibitor may lead to pseudo scaling and serious pipeline corrosion, or even environmental problems. To solve this problem, in this paper, we designed to use the degradable material polylactic acid (PLA) as the carrier, and mixed PLA with the scale inhibitor ethylenediamine tetramethylene phosphonic acid (EDTMPA) to obtain the sustained-release scale inhibition material. The sustained-release performance of the composite material was investigated through static and dynamic release experiments, and at the same time, the inhibition rate of the scale inhibitor in the process of sustained release was also investigated. Scanning electron microscopy (SEM) was used to analyze the morphology of the samples before and after the release of scale inhibitor, and the crystalline phases of calcium carbonate scale samples before and after the addition of scale inhibitors were analyzed by X-ray diffraction (XRD). The results indicate that the prepared composites can continuously release the scale inhibitor for more than 70 days, and have scale inhibition capability throughout the continuous release process. The scale inhibitor released by the slow-release scale-inhibiting material can both inhibit the formation of calcium carbonate and also destroy the calcium carbonate structure formed in the presence of the scale inhibitor, leading to lattice distortion and realizing continuous scale inhibition. This study provides a new strategy to realize the slow-release of scale inhibitors, and the prepared slow-release scale-inhibiting materials have a broad application prospect in the industry.