32results about How to "High permeability recovery value" patented technology

A low-permeability solid-free completion fluid is characterized by comprising the following components in mass percentage: 20-65% of specific gravity regulator, 1-3% of fluid loss agent, 1-2% of antiswelling agent, 0.05-0.1% of crystallization inhibitor, 0.5-1% of anti-collapse agent, 0.5-1% of corrosion inhibitor and the balance of water, wherein the specific gravity regulator is one or a combination of more than two of zinc chloride, zinc bromide, zinc iodide, zinc sulfate, zinc acetate, zinc chlorate and zinc nitrate; the fluid loss agent is carboxymethyl modified starch; the antiswelling agent is diallyl dimethyl ammonium chloride; the crystallization inhibitor is one or a combination of two of nitrilotriacetic acid and EDTA (ethylene diamine tetraacetic acid); the anti-collapse agent is nitro potassium humate; and the corrosion inhibitor is one or a combination of more than two of sodium molybdate, sodium tungstate and sodium chromate. The low-permeability solid-free completion fluid is large in specific weight, good in stability and resistant to high temperature and high pressure, can reduce the swelling rate of clay, improves the core permeability restoring value and does not generate precipitates.

The invention belongs to the technical field of petroleum drilling engineering. The invention provides a deep-water water-based drilling fluid and its application. In terms of mass percentage, it includes: 0.1% to 1.0% viscosity enhancer, 0.1% to 1.0% alkalinity adjustment Agent, 0.5%~3.5% fluid loss additive, 0.5%~1.5% low temperature flow regulator, 1.0%~5.0% shale inhibitor, 15%~25% hydrate inhibitor, 1.0%~3.0% lubricant , 5.0% ~ 10.0% temporary plugging agent and the balance of seawater. The deep-water water-based drilling fluid provided by the invention has constant rheology and reservoir protection properties.

The invention relates to a tackifying and shear strength improving agent and a preparation method thereof. The tackifying and shear strength improving agent disclosed by the invention is prepared through the steps of reacting dimeric fatty acid and polyethylene polyamine according to the molar ratio, namely 1: (0.4-1.6) of carboxyl to amino in the existence of triethylene glycol monobuthyl ether, wherein the reaction temperature is 140-160 DEG C; keeping the temperature until no water comes off, and then, further reacting for 10-20 minutes to finish the reaction; and removing water generated by the reaction while reacting. A soilless oil-based drilling fluid system with the tackifying and shear strength improving agent is good in suspension property, enhanced in solid-phase and stratum water pollution resistance, little in reservoir damage, increased in system permeability recovery value, stable in performance, strong in inhibiting property, good in lubricating property, low in plastic viscosity and high in temperature resistance up to 260 DEG C.