A Develop&Application Of Low Polymer Fracturing Fluid

Hydraulic fracturing is a stimulation of oil and gas wells, wells augmented injection, to improve one of the oil and gas well production and recovery of the most important measures to increase production. The fracturing fluid is in the process of hydraulic fracturing oil and gas working fluid, plays it to pass the pressure, the formation of the strata crack, carry the proppant into the cracks. The quality of the fracturing fluid performance is an important factor in yield after the success of the construction related to the fracturing and impact pressure.With the development of the oil industry, domestic and international oilfield fracturing fluid technology, extensive research, developed a thickening water fracturing fluid from the initial to the later t gel fracturing fluids, fracturing fluids, acidbased fracturing fluid, emulsified fracturing fluid, oil-based fracturing fluid, clean fracturing fluid, such as fracturing fluid system to solve the problem of low recovery in the oil and gas development for the oil field exploration and development and increase reserves and productionmade outstanding contributions. At present, my plant more than three million tons of crude oil unused reserves, most low-permeability layers reserves in proven oil reserves in the future, low-permeability layer of reserves in proportion to the rise. The development of such reservoirs is very difficult, once the damage is difficult to make up to costly, therefore, the application of fracturing technology better exploitation of such reservoirs is of great significance. The performance advantages and disadvantages of the technology of the fracturing fluid composition fracturing fluid chemicals is directly related to the fracturing technical and economic benefits of high and low key. Characteristics of low permeability reservoirs, to minimize the fracturing fluid formation damage is very important, the fracturing fluid used in the development of such reservoirs should not only have good temperature, carrying sand, lowering resistance and breakingplastic properties, it is more important is to have the characteristics of low-residue, low damage, minimize, or avoid formation damage and to further enhance the oil and gas well productivity. Therefore, to study how to further reduce the fracturing fluid formation damage, to become one of the problems need to be resolved oilfield development. Used in fracturing fluid must not only have good temperature, carrying sand, reduction in resistance and gel breaking performance, more importantly, to have the characteristics of low-residue, low damage. Through the above analysis that the research and development of low-polymer fracturing fluid system that is able to solve the contradiction between the low-permeability oil and gas fields fracturing transformation of inputs and outputs. Low-polymer fracturing fluid is a cost close to the ordinary water-based fracturing fluid has a low residue, easy flowback and formation damage is very small features, and its formation damage than clean fracturing fluid, butmuch smaller than the average guanidine gel fracturing fluid. In particular, its low cost, excellent performance, has opened a new path in the transformation of low-voltage, low permeability reservoirs, a large area of low damage fracturing fluid as possible. Its successful development is bound to make a greater contribution to increasing reserves and production, oilfield exploration and development, to improve the low-voltage, low-permeability oil and gas reservoir fracturing process level and the fracturing effect to play a positive role in promoting.In this paper, a large number of laboratory experiments on the basis of research and development of a low polymer fracturing fluid system, the fracturing fluid is less crosslinking time is adjustable, temperature performance, the sand-carrying ability, the residueeasy flowback, etc. the performance is superior to conventional the guanidine glue-based fracturing fluid, especially for low-pressure fracturing in low permeability reservoirs, also applies to other types of reservoirs. Construction yield of low-polymer fracturing fluid was significantly better than the the guanidine glue-based fracturing fluid. Fracturing fluid performance evaluation method proposed formula composition of the fracturing fluid crosslinking time, usually to determine the fracturing fluid gel crosslinking time in two ways:the visual method and viscosity characterization method. The visual method is a certain volume of liquid placed in the automatic mixing, adjust the mix adjuster bottomed whirlpool in a mixing speed of the liquid by adding the proportion of cross-linked liquid, and start timing from joining the cross-linking solution, until the whirlpool healingthis time is the fracturing fluid to freeze the gum crosslinking time. Viscosity characterization method will be a certain ratio of the mixed crosslinking system in the RS-150rheometer (room temperature), the continuous measurement of the viscosity of the crosslinking system change in viscosity-time curve, according to the viscositychanges in apparent extension of the intersection of two tangent curve to determine the gel shear stability of the crosslinking time and temperature stability, rheology, filtration, gel breaking performance, the residue content, and compatibility of various performance parameterstest methods. Determination of fracturing fluid to break the glue of speed and break the glue of the time, provide a reference for the fracturing fluid flowback after the fracturing operation. To carry out the screening and evaluation of low-polymer fracturing fluid thickeners, crosslinking agent and breaker of low-polymer fracturing fluid formulations and overall performance. The residue is the insoluble material remaining in the conventional break the glue of liquid fracturing fluid. For drinking water and water for on-site construction, were prepared by gel fracturing fluid in the electric incubator, broken glue,90%of the gel breaking temperature of the reservoir temperature. Determination of fracturing fluid and formation of crude oil and formation water role can produce emulsion and precipitation, in order to take measures to reduce the formation permeability damage. Fracturing fluid from the thickening agent, crosslinking agent, breaker, PH regulator, clay stabilizing agent cleanup agent composition. Fracturing fluid performance requirements, through a comprehensive survey led to the fracturing fluid gel breaking residue volume, to flowback difficult the various factors affecting the development for low permeability reservoirs with low residue, easy fracturing fluid flowback, it should start from the fracturing fluid residues amount of thickening agent, crosslinker and breaker, under the premise of the conventional performance indicators meet the fracturing fluid, a small amount of residue after the fracturing fluid gel breakingbreak the glue of low viscosity, low surface tension based on the composition of the synthesis and screening of the three main agents to determine the low-polymer fracturing fluid system. On this basis, according to different strata need to filter the appropriate additives, to further improve the low-polymer fracturing fluid system, so that series.The fracturing fluid, the shorter residence time in the well, can take advantage of the elastic energy of formation fracturing fluid flowback rate, thereby reducing the damage caused by fracturing fluid retention in the formation. The fracturing fluid gel breaking more completely, while fracturing fluid residues, the less, the smaller the formation damage. Based on the above theory, taking into account the low pressure, low pressure coefficient of low permeability reservoirs, water-based fracturing fluid flowback is difficult, therefore, the process technology is introduced into the low-polymer water-based fracturing operation. Rapid flowback technology more the purpose is to minimize the damage of the fracturing fluid to the reservoir and support fracture conductivity. In the building during fracturing, wellbore, fracture temperature field model based on the use of temperature profiles to optimize the series formula of low-polymer fracturing fluid, fracturing fluid flowback fast. Formula developed by the success in the Wenxi-3, Wen-5, Mideng, Honghu block application of19wells, temperature meters oilfield fracturing a low polymer fracturing fluid to fully meet the different depth, different well temperature of various types of oil (gas) well fracturing transformation. Nineteen wells the pressure of performance statistics, the average single well yield three hundred and sixty-one ton of crude oil, with good economic and social benefits.