Compatibility of The Dimensions of Polymer Molecular Aggregates to The Pore Throat of a Reservoir

The compatibility of the dimensions of the polymer molecular aggregates and the pore throat of the reservoir were studied. The W section of Tuha oilfield was the study area and polymers produced by Daqing Refining and Chemical Company were used. The permeability limit of the polymer molecules with different molecular masses and concentrations, matching relationship between the dimension of polymer molecular aggregates and pore throat were obtained by experiments. The results of the research are important for the development and implementation of a polymer flooding technical scheme in the middle and late stages of the operation of the Tuha oilfield

Study on Interfacial Tension of Surfactant and Its Oil Displacement Performance

Tuha oil field is located at the Turpan basin in China. Currently, the water content of the main reservoir of the section Y-6 of the Tuha oil field is more than 93% and the recovery rate is less than 20%. At present, an efficient oil displacing agent must be selected for this oil field, which can be used in reservoirs with a high degree of mineralization. Based on the results of experiments measuring the interfacial tension of the surfactant solution and oil, a non-ionic surfactant was selected. Non-ionic surfactant can reduce interfacial tension to the ultra-low level (10{-3} mN/m), and when the amount of adsorption by oil sand is 3, interfacial tension also can maintain at the level of 10{-2} mN/m, so the solution of non-ionic surfactant has good anti-adsorption ability. The results of the oil displacement experiments show that the solution of a non-ionic surfactant can increase the efficiency of oil displacement. But under condition of high water cut, the dominant flow channel in the core is formed, and the surfactant solution flows into the main channel preferentially and reduces the residual oil saturation in the main channel, which leads to a decrease in the resistance coefficient and injection pressure. Therefore, after water flooding, take measures to control the fluid profiles firstly so that the following surfactant solutions change direction in areas not exposed to water in order to achieve the best effect of the increase in oil recovery

Dynamical Modeling and Optimization of the Roll Forming Machine based on the Particle Swarm Optimization with Negative Gradient

Dynamical modeling and optimization of mechanical system is a multi discipline complex problems. This paper deduced Lagrange equations based on 4-DOF one-sided variable cross section roll-forming system and proposed the particle swarm optimization with negative gradient. The mechanical parameters of roll-forming system are optimized by using this algorithm. Optimization results show that the dynamic performance of the roll-forming system has been effectively improved. The algorithm provides theoretic foundation for the optimization design of the roll-forming system

Study on interfacial tension of surfactant and its oil displacement performance

Tuha oil field is located at the Turpan basin in China. Currently, the water content of the main reservoir of the section Y-6 of the Tuha oil field is more than 93% and the recovery rate is less than 20%. At present, an efficient oil displacing agent must be selected for this oil field, which can be used in reservoirs with a high degree of mineralization. Based on the results of experiments measuring the interfacial tension of the surfactant solution and oil, a non-ionic surfactant was selected. Non-ionic surfactant can reduce interfacial tension to the ultra-low level (10-3 mN/m), and when the amount of adsorption by oil sand is 3, interfacial tension also can maintain at the level of 10-2 mN/m, so the solution of non-ionic surfactant has good antiadsorption ability. The results of the oil displacement experiments show that the solution of a non-ionic surfactant can increase the efficiency of oil displacement. But under condition of high water cut, the dominant flow channel in the core is formed, and the surfactant solution flows into the main channel preferentially and reduces the residual oil saturation in the main channel, which leads to a decrease in the resistance coefficient and injection pressure. Therefore, after water flooding, take measures to control the fluid profiles firstly so that the following surfactant solutions change direction in areas not exposed to water in order to achieve the best effect of the increase in oil recovery

Study on interfacial tension of surfactant and its oil displacement performance

Tuha oil field is located at the Turpan basin in China. Currently, the water content of the main reservoir of the section Y-6 of the Tuha oil field is more than 93% and the recovery rate is less than 20%. At present, an efficient oil displacing agent must be selected for this oil field, which can be used in reservoirs with a high degree of mineralization. Based on the results of experiments measuring the interfacial tension of the surfactant solution and oil, a non-ionic surfactant was selected. Non-ionic surfactant can reduce interfacial tension to the ultra-low level (10-3 mN/m), and when the amount of adsorption by oil sand is 3, interfacial tension also can maintain at the level of 10-2 mN/m, so the solution of non-ionic surfactant has good antiadsorption ability. The results of the oil displacement experiments show that the solution of a non-ionic surfactant can increase the efficiency of oil displacement. But under condition of high water cut, the dominant flow channel in the core is formed, and the surfactant solution flows into the main channel preferentially and reduces the residual oil saturation in the main channel, which leads to a decrease in the resistance coefficient and injection pressure. Therefore, after water flooding, take measures to control the fluid profiles firstly so that the following surfactant solutions change direction in areas not exposed to water in order to achieve the best effect of the increase in oil recovery

Compatibility of the dimensions of polymer molecular aggregates to the pore throat of a reservoir

The compatibility of the dimensions of the polymer molecular aggregates and the pore throat of the reservoir were studied. The W section of Tuha oilfield was the study area and polymers produced by Daqing Refining and Chemical Company were used. The permeability limit of the polymer molecules with different molecular masses and concentrations, matching relationship between the dimension of polymer molecular aggregates and pore throat were obtained by experiments. The results of the research are important for the development and implementation of a polymer flooding technical scheme in the middle and late stages of the operation of the Tuha oilfield

Effects of Pyrolysis on Biogas Production during Anaerobic Co-digestion of Corn Stover

The effects of pyrolysis pretreatment on biogas production during anaerobic co-digestion of corn stover were studied. The corn stover characteristics were investigated by performing thermogravimetric analysis using a heating rate of 10.0°C/min and an air atmosphere at atmospheric pressure. Corn stover aliquots pretreated in an electric furnace at 100°C for 360 min, 200°C for 15 min, and 300°C for 5 min were used. Untreated and pretreated corn stover samples were analyzed by scanning electron microscopy and other methods, and the bulk densities and component ratios were compared to identify changes caused by the pretreatments. The amounts of total solids, volatile solids, volatile fatty acids, and total ammonia nitrogen produced when the stover samples were anaerobically digested were measured. The biogas production rate and the methane concentration in the biogas were determined. The substrate-specific methane yields were determined, and the relationships between the yields and pretreatment conditions were assessed. The sample pretreated at 300°C for 5 min produced the most biogas. The corn stover total solid bulk density was directly related to the substrate-specific methane yield, the substratespecific methane yield decreasing as the total solid bulk density increased