Screening And Profile Control Effect Evaluaiton Of Compounded High Temperature Resistance Profile Control Agent System In Steam Flooding

Based on the theory of conjugative effect and synergistic effect, a high temperature resistance gelling profile control system is developed with nitration modification nitro humic acid sodium, HPAM(12 million), cross-link agent I(resorcinol) and cross-link agent II(methenamine). Laboratory experiments are conducted to clarify the laws of temperature tolerance and gelling properties that are influenced by different component contents in the system, three systems are optimized according to different application effect,they are high viscosity blocking agent, middle viscosity plugging agemt, low viscosity displacement agent, respectively. Suspending agent( CMC) content, high temperature resistant inorganic particles mesh number and content are optimized to develop the high temperature resistance gel- particle compounded system, the formula is high viscosity blocking agent gel system+0.7% inorganic particles+0.5%CMC.Based on the actual formation environment, indoor static performance evaluation experiments are conduted to reveal the effect law of gelling viscosity and gelling time that are influenced by temperature, salinity, p H value, and to find the formation environment limination.Based on the actual formation properties and conditions, dynamic performance evaluation experiments are conducted to measure the residual resistance factors, plugging rate, washing resistance, thermostability and static adsorbability of three gel systems. Plugging rate of gel system and compounded system is above 90% and 99% under 280 ℃, respctively. Plugging rates of three gel systems are above 83% after 15 PV steam washing of 15 ml/min under 280 ℃, and still 50% after 30 PV, the plugging rate of compounded system is decreased by 0.35%. Plugging rates of three gel systems are above 73%, and plugging rate of compounded system is still 98.4% and decreased by 0.71% under 280℃ in 100 days’ thermostability test.Combining with the actual geological parameters, production data and experimental data, geologic model of Pilot test area is built and the geological reserves are calculated, Historical production dynamic simulation and dynamic analysis are conducted. The high viscosity blocking agent and low viscosity displacement agent are used in the numerical simulation of steam drive profile control. Plugging radius is optimized and profile control effect is analyzed by the variation of oil increased ratio, water content and oil saturation field to determine the validity of profile control and construction technological parameters. The study helps to provide theoretical and technical support to enhanced oil recovery in late peorid of steam drive.