CN1103131A - Relieving tapping method of oil layer by heat of chemical formation - Google Patents

Abstract

Two groups of pump car and perfusion car are used to pour the water solution of sodium nitrite and the water solution of ammonium chloride into the well simultaneously, the activator of the peak value of reaction heat is industrial glacial acetic acid. The peak value of reaction heat of said system is in the oil layer. Said method features simple and convenient for construction, employing no productive, tubular column, no harm to oil layer, and low cost. It has notable economic effect for eliminating the stoppages of oil well, such as stoppages due to organic material of neighbouring reigion, high interface tension, emulsion and stratum particles.

Description

Relieving tapping method of oil layer by heat of chemical formation

A kind ofly be used to remove oil layer pollution, improve the chemical heat generating method for removing blockage of oil reservoir percolation ability.

Disclose a kind of oil well " the volume increase method that heat chemistry and hot acid are handled " in Soviet Union's " chemical application guide recovers the oil " book that petroleum industry publishing house publishes in July, 1991, this method is divided two programs; The first step is reacted with HCI and Mg, carry out hot chemical treatment, second step was carried out the ordinary salt acid treatment, the method is to exist a large amount of waxs, colloid, asphaltene deposits and calcareous material according to the oil reservoir near wellbore zone, and heat and these materials of dissolving with hydrochloric acid of emitting with heat chemistry reach the oil well production increasing purpose.A kind of " the down-hole heat treatment of high waxy oil well " method that is used for oil well production increasing was disclosed in the third phase in 1991 " petroleum gas collected translation ", its principle is utilize to inject the inferior sodium nitrate of oil well and ammonium nitrate or ammonium chloride to react at the aqueous solution, emit a large amount of heats the mobility of high wax content oil is reduced, reach the periodically purpose of volume increase." the volume increase method that heat chemistry and hot acid are handled " though there is bigger de-plugging to increase the effect of oil, the method is only applicable to low temperature jame or the high well of low temperature carbonate containing content." down-hole treatment of high waxy oil well " method, be used for the high waxy oil well and have effect preferably, but the activator of control reaction heat peak value is a hydrochloric acid, therefore, need in construction operation, use corrosion inhibiter and play the lower tubular column operation, not only prolong the site operation cycle, and thermal peak is wayward, perishable underground equipment.

The objective of the invention is that a kind of organic matter that can remove the near wellbore zone is stifled, high interfacial tension is stifled, emulsion is stifled and formation fines stops up for the oil field provides, do not produce, do not corrode the removal and stimulation method of underground equipment formation damage.

The objective of the invention is to realize by following measure: simultaneously implantation concentration is the 12-18%(weight ratio in oil well) sodium nitrite in aqueous solution and system in contain the industrial glacial acetic acid of 0.2-0.5%, 0.5% FSJ type high temperature film diffusant, 1% BCS-851 type clay stabilizer, it is that 1-2.5 cubic meter/every meter is penetrated out thickness that the 12-18% aqueous ammonium chloride solution of 0.5% 8908 type cleanup additives injects total amount (volume), in injection process: two kinds of liquid are injected in well by two groups of pump trucks respectively simultaneously, the injection rate of two kinds of aqueous solution equates, the reaction heat peak value is in oil reservoir, annotated natrium nitrosum, behind two kinds of aqueous solution of ammonium chloride, inject content is the 1%(weight ratio at once) KCl solution or clear water, its total amount is 0.8 times of pit shaft volume, construction finishes the back closing well resumed production in 4-10 hour again, and whole construction course is not employed flow string.

Below embodiment of the present invention is further described:

First kind of constructure scheme of the present invention is: the two groups of pump jars and the valve that is installed in the well head oil sets annular space that utilize ground, connect the cycling start simultaneously of two groups of pump trucks with threeway, with same discharge capacity, implantation concentration is the 12-18%(weight ratio) sodium nitrite in aqueous solution, with the industrial glacial acetic acid that contains 0.2-0.25% in the system, 0.5%FSJ type high temperature film diffusant, 1%BCS-851 type clay stabilizer, the concentration of 0.5%8908 type cleanup additive is the 12-18%(weight ratio) ammonium chloride, injection rate (volume) is that 1-2.5 cubic meter/every meter is penetrated out thickness, the reaction heat peak value is in oil reservoir inside, after having annotated two kinds of aqueous solution, inject content is the 1%(weight ratio at once) KCI solution, its total amount is 0.8 times of pit shaft volume, construction finishes the back closing well and returned to normal production in 4-10 hour again.

Second kind of constructure scheme of the present invention is: two groups of pump jars that utilize ground, be connected with the threeway on the valve that is installed in the well head oil sets annular space, two groups of pump truck cycling starts simultaneously, with same discharge capacity, implantation concentration is the sodium nitrite in aqueous solution of 12-18%, contain the industrial glacial acetic acid of 0.25-0.5% with system, the concentration of 0.5% FSJ type high temperature film diffusant is the ammonium chloride solution of 12-18%, injects total amount and is (volume) 1-1.5 cubic meter/every meter and penetrate out thickness, and the reaction heat peak value is in oil reservoir, after having annotated two kinds of aqueous solution, inject clear water, its injection total amount is 0.8 times of pit shaft, after construction finishes at once, closing well 4-6 hour, resume production again.

Chemical reaction mechanism of the present invention: natrium nitrosum and ammonium chloride are in the aqueous solution, utilize activator to reduce the activation energy of system, thereby control its reaction speed, it is as follows that two kinds of solution reaction liberated heats and a large amount of gas realize that de-plugging increases oily purpose reaction equation:

Heat energy is by vertical and conduction radially, and the heating near wellbore zone raises the near wellbore zone temperature significantly, so just can remove that water blocking, high interfacial tension block up, organic matter blocks up, and has reduced viscosity of crude simultaneously, thereby has increased the permeability of near wellbore zone.Because the effect of capillary force and formation fines are built bridge and are being shouted the larynx place, some hole liquid advances not go, and a large amount of high-temperature high-pressure nitrogen of emitting in the reaction are entered easily, breaks up the resistance that " bridge formation " destroys capillary force, link up fuel-displaced hole, thereby improve the near wellbore zone percolation ability.

Add industrial glacial acetic acid in system, its effect is the activation energy of reduction system, thus the control chemical reaction velocity, the industry glacial acetic acid is a weak acid, both overcome the corrosion of strong acid, avoided the loss of strong acid in the stratum again, made the out of control deficiency of reaction speed equipment.

Being added with FSJ type high temperature film diffusant in system, is to be used for reducing under the hot conditions interfacial tension, BCS-851 type clay stabilizer is to be used for preventing that the stratum is because of environmental change, stratum clay swell or migration, 8908 type cleanup additives are used for improving the organic matter that dissolves and discharge the stratum

Relieving tapping method of oil layer by heat of chemical formation, have construction simple, employ flow string, to equipment do not have burn into to payzone do not have injury, cost low, remove advantage such as oil layer pollution, the increase oil well productivity has remarkable result.

Claims (1)

1. A kind of chemical heat generating method for removing blockage that is used to improve the oil reservoir percolation ability, it is characterized in that: simultaneously implantation concentration is to contain 0.2-0.5% industry glacial acetic acid (HAC) .0.5% FSJ type high temperature film diffusant in the aqueous solution of natrium nitrosum of 12-18% (weight ratio) and the system in well, the concentration of 0.5%8908 type cleanup additive 1%BCS-851 type clay stabilizer is the ammonium chloride of 12-18% (weight ratio), and injecting consumption is 1-2.5 rice ³/ rice is penetrated out thickness, and two kinds of aqueous solution are injected in well by two groups of pump trucks respectively simultaneously, and discharge capacity equates that two kinds of aqueous solution have been annotated the back and annotated after, and its total amount is 0.8 times of pit shaft volume, and construction finishes the back closing well and returned to normal production in 4-10 hour again.