Controlled Release of Calcium Chloride from Compounded Waterglass-Calcium Chloride Lost Circulation Material
Waterglass-calcium chloride compound is a commonly used lost circulation material.When use this material to control mud losses,the waterglass reacts instantly with calcium chloride as soon as the two chemicals are brought together.Thus,mud loss control with waterglass-calcium chloride compound can only be performed in a complicated"two-liquids"method.To make things easy,the release of calcium chloride from the compound lost circulation material is controlled to try to pump the mixture of waterglass and calcium chloride in one operation.In this study,a resin is used to wrap calcium chloride for controlled release of calcium chloride.By changing the quantities of calcium chloride and the crosslinking agent as well as the type and ratio of the monomers,the effects of these factors on the release of calcium chloride can be understood.The study shows that when wrapping calcium chloride with the resin,if the mass ratio of calcium chloride and the monomer is 1∶4 and the concentration of the crosslinking is 6%,then the time for the waterglass-calcium chloride system to lose fluidity can be extended to 105 min.When the powdered resin wrapping up calcium chloride is rewrapped,if the mass ratio of calcium chloride and the monomer is 1∶2,and the concentrations of the crosslinking agent are both 6%in the first and secondary wrapping,the time for the waterglass-calcium chloride system to lose fluidity can then be extended to 115 min.If sodium chloride is added in the secondary wrapping,then the time for the system to lose fluidity can be extended to 180 min.Analyses with IR spectrum and SEM show that the water-absorbing resin retards the reaction between calcium chloride and waterglass by reducing the contact area between the two chemicals,while the resin itself does not participate in the reaction between waterglass and calcium chloride.
Compounded calcium chloride-waterglass lost circulation materialCalcium chlorideControlled releaseResin
国家科技期刊平台
NSTL
万方数据
