Research On Tight Sandstone Reservoir Fracturing Fluid System And Process Technology

With the development of exploratory, the number of these deep wells and super-deep well, which depth more than 4000 meter, became magnitude. The majority of these deep sandstone reservoir are belong to density and mega-temperature reservoir, which temperature are more than 120 degrees. Through hydraulic fracture to made artificial crack is a key method to link natural crack. Because of the friction along the deep well and dense reservoir fluid absorption ability is low and abnormal high pressure and so on, people transform this kind of reservoir have to under high pressure. Not only it increase the risk of construction, but also it damage to the construction equipment and pipe string. The key question is that it restricts the construction of emissions. For low permeability sandstone we can fracturing with sand, but it is difficult to add sand with low displacement. So it is difficult to achieve large scale renovation of sand on the low permeability reservoir. The drift diameter casing as sand fracturing string can reduce the liquid friction, but due to the large wellbore volume, fracturing proppant into the formation need long time, so that Wellhead pressure response became slowly. It doesn’t favor the construction control of sand plug and dangerous situation.In this paper, the additives properties and liquid properties of high temperature hydraulic fluid had been tested. Meanwhile, the aggravated agent’s characters of aggravated fracturing fluid had been experimented, also the performance of aggravated fracturing fluid had been tested. The hydraulic stimulation design of high temperature tight sandstone reservoir had been optimized in this paper.Combining with the challenges faced by the oilfield production, ideas of increase liquid density are put forward. By increasing the fracture acidizing fluid density, increasing the pressure of the fluid column, reducing wellhead pressure to solve the problem that abnormal high pressure deep well of high pressure reservoir renovation construction. For improving the effect of fracture acidizing and reducing the risk of construction. Through a large number of indoor experiments and researches, this paper develop up to 180℃ high temperature fracturing fluid system. It formed the aggravating fracturing fluid system. The maximum density of 1.5 g/cm3. For the 6000 m deep holes, it can increase 30 MPa fluid column pressure.The aggravated fracturing fluid and 180℃ high temperature fracturing fluid in this paper not only can solve the technology problem in high temperature tight sandstone hydraulic fracturing, but has scientific significance in the hydraulic fracturing of abnormal high temperature, high pressure reservoirs.