Geological radar probing technology finds wide application in engineering projects. The high-precision characteristics of geologic radar should be studied in connection with fine processing and interpretation. This ar...Geological radar probing technology finds wide application in engineering projects. The high-precision characteristics of geologic radar should be studied in connection with fine processing and interpretation. This article discusses such issues as (1) geologic radar noise source and (2) fine processing and interpretation of radar data. It is focused on how to achieve fine processing and interpretation.展开更多
The profile control hard-gel is composed of polyarylamide (5-6g/L), whose molecular weight is 4,000,000 - 7,000,000 and hydrolysis degree is 17.6%, and cross-linking oxidation-reduction agent (Na2Cr2O7 + NH4Cl), with ...The profile control hard-gel is composed of polyarylamide (5-6g/L), whose molecular weight is 4,000,000 - 7,000,000 and hydrolysis degree is 17.6%, and cross-linking oxidation-reduction agent (Na2Cr2O7 + NH4Cl), with an delayed organic acid crosslinker which contains lactic acid/propionic acid/ethanoic acid and ethylene glycol. After research of the influence factors, such as pH, temperature, salinity and the dosage of delayed crosslinker, the optimum condition(pH 5.2, temperature 55℃, salinity < 7g/L) was found. Gelation time (12-144h) can be controlled by adjusting the dosage of the delayed crosslinker. Deep profile control experiments are carried out on heterogeneous models, which contains three serial high permeable and low permeable cores arranged in a parallel. After water flooding (total recovery, 24.3%), the first, second and third high-permeable cores each are sealed in turn by the profile control agent, and the total displacement recovery increases to 46.8%, 62.2% and 69.1% respectively. So, the greater the sealed depth, the larger the enhancing recovery will be. Finally, the oil displacement mechanisms of deep profile control are discussed.展开更多
Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the part...Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the particle size (d50 ) decreased from 1.09 to 0.85 mm, and the tinting strength increased from 100 to 115. The surface-modification as well as the dispersing and stabilizing mechanisms in aqueous solution of the samples were studied by means of IR, Thermal analysis and Zeta potential. The results showed that the modifier molecules acted on the surface of the particles by chemical and physical adsorption, and after the particles were dispersed in aqueous solution, endowing the particle surface with a relatively high negative Zeta potential, thus enhancing electrostatic and steric repulsion between particles for their effective stabilization.展开更多
基金This project is sponsored by The Special Fund of Scientific Instruments of National Natural Science Foundation of China(50127402) and The Geophysical Responses to The High-resolution Exploration for Coal-methane of 973 Program(2002CB211707).
文摘Geological radar probing technology finds wide application in engineering projects. The high-precision characteristics of geologic radar should be studied in connection with fine processing and interpretation. This article discusses such issues as (1) geologic radar noise source and (2) fine processing and interpretation of radar data. It is focused on how to achieve fine processing and interpretation.
文摘The profile control hard-gel is composed of polyarylamide (5-6g/L), whose molecular weight is 4,000,000 - 7,000,000 and hydrolysis degree is 17.6%, and cross-linking oxidation-reduction agent (Na2Cr2O7 + NH4Cl), with an delayed organic acid crosslinker which contains lactic acid/propionic acid/ethanoic acid and ethylene glycol. After research of the influence factors, such as pH, temperature, salinity and the dosage of delayed crosslinker, the optimum condition(pH 5.2, temperature 55℃, salinity < 7g/L) was found. Gelation time (12-144h) can be controlled by adjusting the dosage of the delayed crosslinker. Deep profile control experiments are carried out on heterogeneous models, which contains three serial high permeable and low permeable cores arranged in a parallel. After water flooding (total recovery, 24.3%), the first, second and third high-permeable cores each are sealed in turn by the profile control agent, and the total displacement recovery increases to 46.8%, 62.2% and 69.1% respectively. So, the greater the sealed depth, the larger the enhancing recovery will be. Finally, the oil displacement mechanisms of deep profile control are discussed.
文摘Surface-modification of fine red iron oxide pigment was carried out in an aqueous solution of sodium poly-acrylate. The sedimentation time of modified samples in water increased from 1.05 to 264.4 hours while the particle size (d50 ) decreased from 1.09 to 0.85 mm, and the tinting strength increased from 100 to 115. The surface-modification as well as the dispersing and stabilizing mechanisms in aqueous solution of the samples were studied by means of IR, Thermal analysis and Zeta potential. The results showed that the modifier molecules acted on the surface of the particles by chemical and physical adsorption, and after the particles were dispersed in aqueous solution, endowing the particle surface with a relatively high negative Zeta potential, thus enhancing electrostatic and steric repulsion between particles for their effective stabilization.
