Petrochina Company Limited

Daqing Oilfield Company Limited

Da Qing Petroleum Administration Bureau

Daqing Oilfield Co. Lit

Demin Wang

Yan Wang

Rongjie Zhu

Rong Zhong

Quan Liu

Shiyi Yuan

Chunde Liu

Long Ren

Jintang Liu

Hongyan Wang

Jun Wan

Shumin Zhang

Li Li

Xinmin Song

A downhole oil, gas, water and sand separation method and separator (). The downhole oil, gas, water and sand separation method comprises: step: dividing an oil jacket annulus into a plurality of spaces in an outflow direction of produced liquid, wherein each space is provided with an accommodating cavity () communicated with the oil jacket annulus; step: arranging a plurality of liquid inlet hole groups () in a liquid outlet pipeline () of the produced liquid in the outflow direction of the produced liquid, wherein each of the liquid inlet hole groups () is communicated with one of the accommodating cavities (); and step: separating oil, gas and water after the crude oil in the oil jacket annulus flows into each of the accommodating cavities (), wherein separated oil drops or bubbles flow back to the oil jacket annulus from the accommodating cavities (), and separated produced liquid simultaneously flows into the liquid outlet pipeline () through the plurality of liquid inlet hole groups (). The downhole oil, gas, water and sand separation method and separator can realize a rapid downhole oil-water or gas-water separation in the high water-content crude oil.

Downhole oil, gas, water and sand separation method and separator

Betaine surfactants of formula (I) and preparation methods and uses thereof are provided. The surfactant can decrease the interfacial surface tension of crude oil till 10mN/m, have the capabilities of antiheating (130&#xb0; C.), antimineralizing and antidiluting, and can be used in the field of tertiary oil recovery. 

Betaine surfactants and preparation methods and uses thereof

The present invention relates to a crown-shaped separation device for separating oil and water in a well. Separator joints are sleeved on a central tube, and a separator is arranged between adjacent separator joints. Settlement cups are sleeved on the central tube, and two adjacent settlement cups are inserted together. A multi-rib separating bowl is embedded in the settlement cup. The settlement cup is crown shape. The bottom of the settlement cup is formed with multiple ribs. An angle is formed between the convex rib of the bottom of the settlement cup and the horizontal line. The top edge of the settlement cup is sawtooth shape corresponding to the shape of the cup bottom. An annular space is formed between the cup base of the settlement cup and the central tube. The central tube corresponding to the annular space is provided with a fluid inlet. The shape of the multi-rib separating bowl is identical to that of the bottom of settlement cup, and the multi-rib separating bowl is provided with a fluid passage. The downhole device solves the effective separation of oil and water.

Crown-shaped separation device for separating oil and water in well

A corrugated settling cup () is provided, wherein the cup has a cup body, an opening and a location step () are provided at the bottom () of the cup body, several location holes () are formed at the top of the location step (), location projections () corresponding to the location holes () are formed at the bottom () of the corrugated settling cup (), wherein the external profile of the corrugated settling cup body rises along the axial direction in a corrugated shape. A multi-cup uniform flux gas anchor is provided, wherein the gas anchor includes a central pipe (), several corrugated settling cups (), several settling cups protection bodies (6) and a well-flushing valve (), wherein the external profile of the corrugated settling cup body rises along the axial direction in a corrugated shape.

Corrugated settling cup and a multi-cup uniform flux gas anchor

A foam drive method for enhancing oil recovery efficiently is initiated by injecting into a subterranean oil-bearing formation, an aqueous polymer solution as a preceding-slug. This is followed by periodically injecting simultaneously or alternately a non-condensible gas and an aqueous solution of foaming composition to form a combined foam under ground or periodically injecting the combined foam formed beforehand by the gas and said aqueous solution above ground. The aqueous solution of foaming composition comprises an alkali, a surfactant and a polymer. Thereafter, an aqueous polymer solution used as a protecting-slug is injected into the formation; followed by continuing water-flooding.

Foam drive method

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Beijing, China

Demin Wang