Cement slurries used in drilling – types, properties, application

The cement slurry is formed by mixing water with Portland cement or with a mixture of cement containingf various additives. The most important goal of cementing boreholes is to counter the inflow of water into productive levels of rocks with oil and gas. Physico-chemical conditions in borehole have a major effect on the properties of the grouts (bonding, hardening and durability). The most important of these are increased temperature and pressure as well as the presence of reservoir waters, drilling mud and gas migration. The article specifies the requirements for cement grouts used in drilling. The formation process and various types of cement have been characterized due to their phase composition and chemical and mineralogical composition. The treatment methods for the cements of drilling cements are also given. Finally, examples of drilling in the Polish Lowlands are illustrated as a sample of many factors affecting the type, properties and application of cement.