阅读说明：本技术 一种提高天然气采收率方法及其产品生产工艺 (Method for improving natural gas recovery ratio and product production process thereof ) 是由 明爱华 于 2019-11-20 设计创作，主要内容包括：本发明涉及天然气开发技术领域,具体地说,涉及一种提高天然气采收率方法及其产品生产工艺。其包括乙二醇全氟丙酸酯气湿剂,乙二醇全氟丙酸酯气湿剂包括以下原料试剂：乙二醇HOCH<Sub>2</Sub>CH<Sub>2</Sub>OH,五氟丙酸CF<Sub>3</Sub>CF<Sub>2</Sub>COOH,对甲苯磺酸,乙醇重结晶和碳酸钠溶液；乙二醇HOCH<Sub>2</Sub>CH<Sub>2</Sub>OH,五氟丙酸CF<Sub>3</Sub>CF<Sub>2</Sub>COOH和对甲苯磺酸均为分析纯级别。该发明的设计消除了液锁、消除了毛管阻力,减小了天然气产出的阻力；二是提高了气相渗透率,增大了气相流动通道的体积,使天然气产出量增大,提高低效井生产产量,使间歇并转变为常开井,提高了天然气单井产量最终提高了天然气采收率。(The invention relates to the technical field of natural gas development, in particular to a method for improving natural gas recovery ratio and a product production process thereof. The ethylene glycol perfluoropropionate gas wetting agent comprises the following raw material reagents: ethylene glycol HOCH 2 CH 2 OH, pentafluoropropionic acid CF 3 CF 2 COOH, to nailBenzenesulfonic acid, ethanol recrystallization and sodium carbonate solution; ethylene glycol HOCH 2 CH 2 OH, pentafluoropropionic acid CF 3 CF 2 COOH and p-toluenesulfonic acid are both analytically pure grades. The design of the invention eliminates liquid lock, eliminates capillary resistance and reduces resistance of natural gas production; and secondly, the gas phase permeability is improved, the volume of a gas phase flow channel is increased, the output of natural gas is increased, the production yield of a low-efficiency well is increased, the intermittent operation is converted into a normally opened well, the yield of a single natural gas well is increased, and the natural gas recovery ratio is finally increased.)

1. A product for improving natural gas recovery efficiency comprises ethylene glycol perfluoropropionate wetting agent, and is characterized in that: the ethylene glycol perfluoropropionate gas wetting agent comprises the following raw material reagents: ethylene glycol HOCH₂CH₂OH, pentafluoropropionic acid CF₃CF₂COOH, p-toluenesulfonic acid, ethanol recrystallization and sodium carbonate solution; ethylene glycol HOCH₂CH₂OH, pentafluoropropionic acid CF₃CF₂COOH and p-toluenesulfonic acid are both analytically pure grades.

2. A process for producing an enhanced gas recovery product comprising the enhanced gas recovery product of claim 1, the process comprising the steps of:

s1, stirring the mixture in a four-mouth bottle provided with a thermometer, a water separator and a condenser tube through a magnetic stirrer under the protection of nitrogen, and sequentially adding ethylene glycol, toluene, pentafluoropropionic acid and p-toluenesulfonic acid;

s2, heating to 110 ℃ in an oil bath kettle under normal pressure, carrying out reflux reaction for 7 hours at constant temperature until no water is generated in the water separator, and finishing the reaction;

s3, distilling under reduced pressure to remove toluene, and cooling to room temperature;

s4, washing the mixture by using a saturated sodium carbonate aqueous solution until the pH value is neutral;

s5, washing with saturated saline solution to remove unreacted raw materials and p-toluenesulfonic acid;

s6, drying in a vacuum drying oven to obtain yellow transparent liquid, namely ethylene glycol perfluoropropionate hydrosol, which is recorded as FQ.

3. The enhanced gas recovery product production process of claim 2, wherein: the synthesis mechanism of the ethylene glycol perfluoropropionate wetting agent FQ is as follows:

pentafluoropropionic acid CF₃CF₂The molar number n of COOH used₁；

Ethylene glycol HOCH₂CH₂OH number of moles n₂；

If, n₁≤n₂Then the synthesis reaction formula is:

CF₃CF₂COOH+HOCH₂CH₂OH→CF₃CF₂COOH₂CH₂OH+H₂O；

if, n₁＞n₂Then the synthesis reaction formula is:

2CF₃CF₂COOH+HOCH₂CH₂OH→(CF₃CF₂COO)₂CH₂CH₂OH+H₂O。

4. an enhanced natural gas recovery process comprising the enhanced natural gas recovery product of claim 1, the process comprising: and (3) injecting ethylene glycol perfluoropropionate gas wetting agent into the gas drive gas reservoir.

Technical Field

The invention relates to the technical field of natural gas development, in particular to a method for improving natural gas recovery ratio and a product production process thereof.

Background

The 21 st century is a natural gas century, and natural gas is more and more important in national economy as a cleaner, better and more economic energy and chemical raw material. As most of gas reservoirs belong to low-permeability and water-flooding gas reservoirs, the recovery ratio is low, and the natural gas consumption in China is increased year by year, the improvement of the recovery ratio of the gas reservoirs has important economic and social values. Improving gas reservoir recovery Efficiency (EGR) refers to a new technology, a new method or a new process for realizing the improvement of the gas reservoir recovery efficiency on the basis of the gas reservoir recovery efficiency of water drive, gas drive or other natural energy exploitation under the existing economic technology conditions. The ideal gas-flooding gas reservoir is that no formation water and no condensate oil exist in the trap of the gas reservoir, the gas-flooding power is generated by the elastic expansion of the gas reservoir, and natural gas smoothly reaches a shaft from a matrix capillary of the gas reservoir through a microfracture to realize effective extraction of the natural gas and reach the final recovery ratio all the time.

The actual gas drive reservoir trap contains not only natural water but also some condensate due to the high reservoir pressure. The existence of water and condensate generates water lock and oil lock in a reservoir matrix gas storage capillary, which are collectively called liquid lock. Due to the existence of the liquid lock, the wettability of the surface of the capillary is inconsistent, the surface of the capillary has the phenomenon of disorder of air humidity, water humidity and oil humidity, capillary force is generated in the capillary section with water humidity and oil humidity, the direction of the capillary force is opposite to the direction of natural gas production, namely the capillary force is the resistance of natural gas flowing from the pore of the matrix gas storage to the shaft. Due to the existence of capillary force, the yield of the natural gas well is reduced, and some production wells slowly become incapable of continuous production, only intermittent production or production stoppage for a long time, so that the natural gas recovery rate is finally reduced.

Disclosure of Invention

The invention aims to provide a method for improving natural gas recovery ratio and a product production process thereof, so as to solve the problems in the background technology.

In order to achieve the above objects, in one aspect, the present invention provides a product for enhancing natural gas recovery, which comprises a glycol perfluoropropionate gas wetting agent, wherein the glycol perfluoropropionate gas wetting agent comprises the following raw materials: ethylene glycol HOCH₂CH₂OH, pentafluoropropionic acid CF₃CF₂COOH, toToluene sulfonic acid, ethanol recrystallization and sodium carbonate solution; ethylene glycol HOCH₂CH₂OH, pentafluoropropionic acid CF₃CF₂COOH and p-toluenesulfonic acid are both analytically pure grades.

On the other hand, the invention provides a production process for improving the natural gas recovery ratio, which comprises the following production process steps:

s1, stirring the mixture in a four-mouth bottle provided with a thermometer, a water separator and a condenser tube through a magnetic stirrer under the protection of nitrogen, and sequentially adding ethylene glycol, toluene, pentafluoropropionic acid and p-toluenesulfonic acid;

s2, heating to 110 ℃ in an oil bath kettle under normal pressure, carrying out reflux reaction for 7 hours at constant temperature until no water is generated in the water separator, and finishing the reaction;

s3, distilling under reduced pressure to remove toluene, and cooling to room temperature;

s4, washing the mixture by using a saturated sodium carbonate aqueous solution until the pH value is neutral;

s5, washing with saturated saline solution to remove unreacted raw materials and p-toluenesulfonic acid;

s6, drying in a vacuum drying oven to obtain yellow transparent liquid, namely ethylene glycol perfluoropropionate hydrosol, which is recorded as FQ.

Preferably, the synthesis mechanism of the ethylene glycol perfluoropropionate FQ is as follows:

pentafluoropropionic acid CF₃CF₂The molar number n of COOH used₁；

Ethylene glycol HOCH₂CH₂OH number of moles n₂；

If, n₁≤n₂Then the synthesis reaction formula is:

CF₃CF₂COOH+HOCH₂CH₂OH→CF₃CF₂COOH₂CH₂OH+H₂O；

if, n₁＞n₂Then the synthesis reaction formula is:

2CF₃CF₂COOH+HOCH₂CH₂OH→CF₃CF₂COO₂CH₂CH₂OH+H₂O。

on the other hand, the invention provides a method for improving the natural gas recovery ratio, which comprises the following steps: and (3) injecting ethylene glycol perfluoropropionate gas wetting agent into the gas drive gas reservoir.

Compared with the prior art, the invention has the beneficial effects that: the chemical ethylene glycol perfluoropropionate gas wetting agent is injected into a gas drive gas reservoir to change the surface wettability of a gas storage capillary in a substrate of the gas drive gas reservoir into gas wetting: firstly, the liquid lock is eliminated, the capillary resistance is eliminated, and the resistance of natural gas production is reduced; and secondly, the gas phase permeability is improved, the volume of a gas phase flow channel is increased, the output of natural gas is increased, the production yield of a low-efficiency well is increased, the intermittent operation is converted into a normally opened well, the yield of a single natural gas well is increased, and the natural gas recovery ratio is finally increased.

Drawings

FIG. 1 is a flow chart of the production process of the product of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.