Study on Evaluation and application of polyacrylamide for oil displacement - CHINAFLOC
Home > News > 

News

Study on Evaluation and application of polyacrylamide for oil displacement
2015-09-05 06:07:07
    Polymer products of polymer flooding in Daqing oil field are mainly used for partially hydrolyzed polyacrylamide HPAM. It is generally believed that polyacrylamide can play an important role in mediating the rheological properties of the injected water, increasing the viscosity of the driving fluid, improving the water flooding efficiency. However, due to the differences in the ionic composition and content in the underground water, the molecular morphology and molecular weight of the polyacrylamide are not required. The comprehensive performance of the polyacrylamide product will directly affect the technical and economic results of polymer flooding. The evaluation method of eleven physical and chemical properties of conventional polymers can not be used to evaluate the applicability of various polymer products to Daqing oilfield. Because of the high molecular weight and low molecular weight polymer, a new type of polymer was introduced into the molecular chain, and compared with the conventional polymer, the solution properties of the polymer were significantly changed. Lead to the accuracy of the conventional detection method, adaptive variation. The main purpose of this project is to establish an absolute method for the study of the molecular weight of polyacrylamide (PAM) and hydrolyzed polyacrylamide (HPAM), and to study the molecular size of the polymer, and the feasibility of GPC- light scattering. The main contents include: Light Scattering Determination of experimental conditions and evaluation of viscosity measurement results; effect of ion concentration in the solution of molecular dimensions, the second virial coefficient; explore the polymer solution of the theta condition; GPC light scattering combined with of injected and produced fluid in the polymer molecular weight distribution of evaluation. The filter factors of low molecular weight polyacrylamide are mostly met the standard of the original standard, so it is not adjusted for it. For ultra high molecular weight polyacrylamide filter factor index to make appropriate anti wide, according to the research results, we believe that the polymer molecular weight between 1600 and 19000000 of the filter factor to relax to 3 is appropriate, the molecular weight is greater than 19000000 of the provisional regulations. In different periods, different types (including hydrophobic associating polymer, high molecular weight polymer, low molecular weight polymer, low molecular weight polymer, 47 WP=53) were carried out to evaluate the properties of eleven physical and chemical properties, such as, viscosity retention rate, etc.. 
    With the advanced technology of infrared, mass spectrometry, chromatography and light scattering, the structure of the polymer was analyzed qualitatively. Then, according to the actual needs of the research and put forward high accuracy, wide range of detection method. Comprehensive evaluation of different polymers including physical and chemical properties, salt resistance, shear resistance, stability, resistance coefficient and residual resistance coefficient, and core flooding experiment results were comprehensively evaluated. Several new polymer products suitable for the polymer flooding of wastewater are selected. The optimized salt resistant polymer showed good physical and chemical treatment. Properties, salt resistance, shear resistance, viscoelasticity, stability, and good indoor displacement experiment results. Ultra high molecular weight polymer solution has a network structure in water and wastewater, which has good viscosity and high oil displacement effect, which indicates that the structure of the polymer is beneficial to improve the viscoelasticity of polymer solution. Associating polymer with molecular weight polymer is different, its molecular in aqueous solution and uniform dispersion, the viscosity of the system is not as fast as the viscosity of the polymer system. In order to better utilization of sewage and high calcium and magnesium in water for preparation of low molecular weight salt resistant polymer, improvement in low permeability layer of polymer flooding oil effect, carried out, including physical and chemical properties, sewage system viscosity, flow properties, core flooding results, rheology characteristics and visco elastic, the comprehensive performance of indoor work, preliminary screening the two small field test test products at present, flooding with polymer performance index is more, it is necessary to accurately distinguish what characteristics are conducive to the actual displacement. Firstly, the comprehensive performance evaluation of different polymers should be carried out, and the evaluation of the environmental conditions should be consistent with the present field, and combined with the experimental results of multi segment core, the main characteristics of different polymer products and auxiliary characteristics are proposed. Secondly, the geological conditions are close to the single well and the well group injected with the polymer, the effect of the field application is further verified by the effect of different characteristics on the actual oil displacement effect. 48 the evaluation and application of WP=54 in the study of the properties of the new type of polymer in Jilin University has not been established. The qualitative study on the new type of polymer should be based on the characteristics of oil displacement efficiency, mobility and diversion, and the compatibility of reservoir.
    Polyacrylamide (PAM) and its derivatives have been used in oil recovery, water treatment, papermaking, mineral processing and other fields. It is a kind of water soluble polymer, which can be used as an auxiliary agent for paper making, adhesive, leather tanning agent, flocculant and filtrate reducer. Added crosslinking agent PAM polymer has excellent swelling, water and water performance, as "diapers" material, soil water holding agent, oil field water plugging agent. So the research of this paper has good practical value and broad application prospect. In this paper, we have studied the synthesis of the nuclear shell structure. The PAM derivatives of the core-shell structure have more excellent performance than the ordinary PAM derivatives. In this paper, the influence factors such as monomer, emulsion system, initiation system, temperature and so on, the stability of polymer emulsion and monomer conversion, and the morphology of polymer microspheres were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), and the infrared spectra, solid content, hydrolysis degree, characteristics of viscosity, swelling, water absorption rate, PAM (Tg) and sealing performance were determined. The synthesis of polyacrylamide (PAM) - based polymers by inverse emulsion polymerization was used to synthesize the acrylamide as the main body and the crosslinking agent. The optimum conditions for the stable polymer emulsion are discussed, including the reaction temperature, the heating mode, the oil / water phase dispersion, the type and dosage of emulsifier. Then, the influence of the amount of initiator, the amount of acrylamide, the amount of -2- 2-, the amount of crosslinking agent, the amount of crosslinking agent on the monomer conversion and the swelling property of polymer microspheres were investigated by single factor experiment. Finally, the optimal conditions are verified by parallel experiments, and the conversion rate of the monomer is maintained at more than 90%. 
    The infrared spectra, water absorption rate, solid content and hydrolysis degree of the polymer microspheres were determined. On the basis of this, the polymer microspheres were modified by the addition of soluble starch to the monomer, and the conversion rate, solid content, hydrolysis degree and sealing property of the polymer were studied by four factors and three level orthogonal experiment. At the same time, the PAM polymer microspheres were prepared by inverse emulsion polymerization, with styrene and acrylamide as the main body and oil and water phase simultaneously. On the basis of the second chapter, by using the single factor method, the type and dosage of emulsifier, the dosage of emulsifier, the adding time and amount of oil phase monomer were discussed, and the four level orthogonal experimental method was used to investigate the monomer conversion rate, solid content, hydrolysis degree, sealing performance, etc.. The above research lays the foundation for the industrial production and application.