RU2282019C2 - Method and device for formation fluid lifting - Google Patents

Abstract

FIELD: formation liquid production from wells, particularly to operate oil and water pumping wells.

SUBSTANCE: method involves providing formation fluid in chamber; supplying pressurized gas in chamber; lifting formation liquid via production tubing. The formation liquid is lifted in several stages via several chambers having accumulation chambers located over them. Above chambers are divided with check valves. Pressurized gas is cyclically supplied in odd-numbered chambers along with providing pressure in even-numbered chambers close to atmospheric pressure. Then gas is supplied in even-numbered channels along with providing pressure in odd-numbered chambers close to atmospheric pressure. After formation liquid lifting into accumulation chambers gas pressure is approximated to atmospheric pressure. End valve adapted to reduce and stabilize pressure in chamber is installed on lower end of production tubing. Formation liquid is lifted from well and is carried out when gas pressure in supply line is less than formation pressure. Device comprises production tubing for formation liquid lifting, chambers and check valves installed in the chambers. Device additionally has gas supply pipelines. Production tubing is composed of odd-numbered and even-numbered channels along the full production tubing length. Accumulation chambers are located over the even-numbered and odd-numbered chambers and are separated from the chambers with check valves. The production tubing has pressure reduction valve installed at lower end thereof and adapted to reduce, stabilize pressure in chamber and to lift formation liquid from well when pressure in gas supply line is less than formation pressure. One gas supply line is connected to odd-numbered chambers, another line is connected with even-numbered ones.

EFFECT: reduced power inputs for liquid lifting from well.

7 cl, 1 dwg

Description

The invention relates to the field of production of formation fluid from wells and can be used in the operation of water and oil pumping wells.

A known pump for lifting formation fluid from a well (patents No. 5470206, No. 5522463, No. 6027314 USA). In various embodiments, a general method of squeezing fluid into a column is used to lift formation fluid from a substitution chamber using compressed gas. The process of raising the fluid is controlled by two valves located on the top of the substitution chamber. Liquid is taken from the well by means of the reciprocating movement of the column for lifting liquid from the well and a check valve located at the bottom of the column. The main disadvantage of the known device is that a mechanism is needed to organize the reciprocating movement of the column through which the fluid rises from the well. Gas must be supplied to the substitution chamber at pressures in excess of reservoir pressure.

Known substitution elevator for the periodic operation of gas lift wells (AS No. 1106896). The supply of compressed gas to the substitution chamber from the annulus occurs periodically, while the liquid is displaced from the substitution chamber into the tubing string and then to the surface. The disadvantages of this device include the fact that when the liquid is displaced to the surface, the pressure inside the substitution chamber must be maintained greater than the reservoir pressure, as well as the need to use a packer in the lower part of the column.

Closest to the claimed invention (prototype) is a replacement elevator for periodic operation of a gas-lift well (A.S. No. 1640376). The replacement elevator also contains a replacement chamber associated with a column of elevator pipes equipped with start valves. The replacement chamber contains check ball replacement valves. The rise of the oil column occurs cyclically by periodically supplying gas from the annulus through the start-up valve at a pressure higher than the reservoir pressure. The disadvantage of this known device is the need to supply gas at a pressure in excess of the reservoir, i.e. use a powerful compressor on the surface and the need to put a packer at the bottom of the well.

The aim of the invention is to reduce energy costs when lifting fluid from the well.

The method of raising formation fluid from the well includes the entry of formation fluid into the substitution chamber, supplying gas under pressure to the substitution chamber, raising the formation fluid through the elevator string. The formation fluid is raised stepwise through several substitution chambers with accumulation chambers located above them, separated by non-return valves, gas is supplied under pressure cyclically first to the odd substitution chambers as the gas pressure approaches the atmospheric even chambers, and then to the even substitution chambers as the pressure approaches gas in odd substitution chambers to atmospheric, while the gas pressure is brought closer to atmospheric after lifting the formation fluid into the accumulation chambers, at the bottom of the elevator columns We install an end valve to lower and stabilize the pressure in the substitution chamber, and the formation fluid is lifted from the well at a gas pressure in the supply line less than the reservoir pressure. The features of the invention include the fact that associated gas is used to lift the formation fluid from the well, and a compressor is used to compress the associated gas from the well.

The device for raising the reservoir fluid consists of an elevator column for raising the reservoir fluid, replacement chambers and check valves in the replacement chambers, characterized in that it further comprises lines for supplying gas, the elevator column along the entire height consists of even and odd replacement chambers with located above them accumulation chambers, separated from the replacement chambers by check valves. At the lower end of the elevator column there is an end valve for lowering the pressure in the substitution chamber, stabilizing it and raising the formation fluid from the well when the gas pressure in the supply line is less than the reservoir pressure. One of the gas supply lines is connected to the odd substitution chambers, and the other to the even substitution chambers. At the lower end of the elevator column, an end valve is installed to lower and stabilize the pressure in the substitution chamber, and the substitution chambers are separated by accumulation chambers with check valves and contain a pipe on which the check valve is located.

The proposed method and device for raising the reservoir fluid are illustrated in the drawing.

In the casing 1 there is a device for raising the reservoir fluid, consisting of lines 2 and 3 of gas supply to even 4 and odd 5 substitution chambers. The replacement chamber contains a check valve 6 and a check valve 7, as well as a pipe 8, on which the check valve 7 is located. Above the replacement chambers are accumulation chambers 10. At the end of the column of elevator pipes there is an end valve 9. The entire column of elevator pipes 11 is dialed from the same sections. The number of sections depends on the depth of the well (bedding of formation fluid).

A device for lifting formation fluid works as follows. After lowering the device into the well, the formation fluid does not enter the column of elevator pipes 11 due to the end valve 9 at the end of the column of elevator pipes 11, as well as the pressure in the gas supply lines 2 and 3. When the gas pressure approaches atmospheric pressure in the odd gas supply line 3, the end valve 9 opens and the reservoir fluid through the inlet check valve 6 enters the lower (odd) substitution chamber 5. When the pressure in the lower chamber is less than the working pressure in lines 2 and 3 gas supply, the end valve 9 is closed. An odd gas supply line 3 starts supplying gas under pressure. The use of the end valve 9 allows the pumping of the column of formation fluid at a gas pressure from line 3 less than the reservoir, while lifting the column of formation fluid through the discharge check valve 7 into the accumulation chamber 10, the check check valve 6 is closed. After raising the column of formation fluid into the upper accumulation chamber 10, the pressure in the odd gas supply line 3 is brought closer to atmospheric and the formation fluid through the end valve 9 and the non-return valve 6 again enters the lower substitution chamber, the cycle repeats. When the accumulation chamber 10 is filled with formation fluid, it begins to flow into the upper (even) substitution chamber in a similar way, from which the reservoir fluid is pumped higher under the action of gas pressure from the even gas supply line 2. Thus, by alternately supplying and lowering the gas pressure in the gas supply lines 2 and 3, the formation fluid rises to the surface, while the pressure below the reservoir is used to raise the formation fluid through the use of end valve 9. This allows you to use gas to lift fluid from the well at low pressure relative to the pressure of the reservoir fluid.

The proposed method and device for raising the reservoir fluid allows the use of associated gas pressure or a low power compressor when lifting the reservoir fluid from great depths.

Claims (7)

1. The method of raising the reservoir fluid from the well, including entering the reservoir fluid into the substitution chamber, supplying gas to the substitution chamber under pressure, raising the reservoir fluid through the elevator column, characterized in that the reservoir fluid is raised stepwise along several substitution chambers with accumulation chambers located above them separated by non-return valves, and gas under pressure is supplied cyclically first to the odd substitution chambers as the gas pressure in the even substitution chambers is atmospheric, and then to the even substitution chambers as the gas pressure in the odd substitution chambers approaches atmospheric, while the gas pressure is brought closer to atmospheric after the formation fluid is raised into the accumulation chambers, an end valve is installed at the lower end of the elevator column to lower and stabilize the pressure in the substitution chamber, and the reservoir fluid is raised from wells are carried out at a gas pressure in the supply line less than reservoir pressure. 2. The method according to claim 1, characterized in that the associated gas from the well is used to raise the reservoir fluid. 3. The method according to claim 1, characterized in that a compressor is used to compress the associated gas from the well. 4. A device for raising the reservoir fluid, consisting of an elevator column for raising the reservoir fluid, replacement chambers and check valves in the substitution chambers, characterized in that it further comprises gas supply lines, the elevator column along the entire height consists of even and odd substitution chambers with accumulation chambers located above them, separated from the replacement chambers by check valves, and has an end valve at the lower end to lower the pressure in the substitution chamber, stabilize it, and raise reservoir fluid from a well at a gas pressure in its supply line less than reservoir pressure, while one of the gas supply lines is connected to the odd substitution chambers, and the other to the even substitution chambers. 5. A device for raising the reservoir fluid according to claim 4, characterized in that an end valve is installed at the lower end of the elevator column to lower and stabilize the pressure in the replacement chamber. 6. The device for raising the reservoir fluid according to claim 4, characterized in that the substitution chambers are separated by accumulation chambers with check valves. 7. The device for lifting the reservoir fluid according to claim 4, characterized in that the replacement chamber contains a pipe on which the check valve is located.