Increase Well Productivity

Acid treatment is widely used for enhancing oil recovery. One of the progressive methods of acid treatment employed presently is the productive formation bottom hole zone treatment by nitric acid. In spite of many advantages such as decreasing oil viscosity, it leads to corrosion and failure of sealing elements. To prevent these occurrences the nitric acid before being injected into a well is converted to an inactive form – its complex with Carbamide or, in other words, to Carbamide nitrate. The technology is highly efficient and can be used to treat efficiently bottom-hole zones of beds in porous, fissured porous and fissured reservoirs, at different depths, pressure and temperature. It is acceptable for both common fields and high-viscous oil fields at different climatic conditions. Results show that utilization of Carbamide nitrate for formation acid treatment provides greater vertical sweep than when treating by solutions of hydrochloric and nitric acid. In this paper, method of increasing well productivity by using Carbamide nitrate is investigated.