RU2122629C1 - Method of killing oil and gas wells - Google Patents

Abstract

FIELD: oil and gas fields; applicable in completion, servicing and workover of wells with use of Senoman and suboil water. SUBSTANCE: method includes preparation of killing fluid in the form of salt solution of required density and its filling into well. Killing fluid is prepared in desalinating plant. Supplied to its inlet is filtered initial Senoman water from water intake. Required density of salt solution at the outlet of desalting plant is attained by increasing the time of evaporation or evaporation at several stages using for this purpose desalinating plant. Initial water is filtered from suspensions above 0.5 mm in size and from other foreign objects. EFFECT: simplification of process. 4 cl

Description

 The invention relates to oil and gas fields and can be used in development, maintenance and overhauls of wells using Cenomanian and produced water.

 There is a method of killing oil and gas wells, in which a killing fluid is prepared in the form of a saline solution of the required density and poured into the well (see Gorodnov V.F. Physicochemical methods for preventing complications in drilling, second edition, revised and updated. M. : Nedra, 1984, pp. 209-210).

 The objective of the invention is to simplify the process of preparing a kill fluid in the form of a saline solution (brine) of the required density.

 The problem is solved in that in the method of killing oil and gas wells, in which a killing fluid is prepared in the form of a saline solution of the required density and poured into the well, a saline solution of the required density is prepared in a desalination plant, while filtered Senoman water is fed to its input from the water intake, and the desired density of the saline solution at the outlet of the desalination plant is achieved by increasing the evaporation time or by performing the evaporation in several stages.

 Use desalination plant DOU GTPA-10.

 Filtration of the initial Cenomanian water is carried out from suspensions larger than 0.5 mm and other debris.

 The distillate formed at the outlet of the desalination plant, in addition to saline, is used to provide boiler houses with feed water, for household and drinking needs.

 The DOU GTPA-10 installation contains an evaporator, a remote separator, a condenser with a degasser, a distillate cooler, a water heater, a distillate collector with a float regulator, an electric pump, a separator water trap, a brine ejector, and an ion-exchange filter.

 The installation works as follows.

 The original Cenomanian water, filtered from suspensions larger than 0.5 mm and other debris, is supplied from the intake to the installation. Water passes through the tube space of the condenser, where it is heated by the secondary steam of the last fifth stage of the evaporator. Next, the water enters the heater, which is built into the evaporator, where it is heated by the steam blowing the heating sections of the evaporation stages.

 From the evaporator heater, Cenomanian water through the sprinkler enters the horizontal-tube bundle of the first evaporation stage, where partial evaporation of water occurs due to steam from an external source introduced into the heat exchange tubes. Partially evaporated water from the first stage through the irrigation device irrigates the horizontal-tube bundle of the second stage and is partially evaporated in it by the secondary vapor condensing inside the bundle tubes from the first stage. Before the secondary steam of the first stage enters the pipes of the second stage, it is cleaned using a fine-flow spray catcher. In the subsequent stages of the evaporator, the same processes occur as in the first and second stages of the evaporator. From the fifth stage of the evaporator, water is drained into the tank and pumped into the irrigation device of the sixth stage of the evaporator. In the steps of the evaporator, the processes of evaporation of water, cleaning of the generated steam from droplets in a fine-flow spray separator and steam condensation inside the heat exchange tubes are repeated. Evaporated water is drained from the tenth stage of the evaporator into the tank and then pumped into the discharge channel.

 The heating steam coming from an external source, with the help of the steam compressor used in the installation, takes part of the secondary steam from the first stage and feeds into the heat exchange pipes of the first stage. In these pipes, part of the steam condenses, providing evaporation of part of the water, and approximately 10% of the steam from the heat exchange pipes (purge steam) passes into the heater, where it heats the water directed to desalination. The steam generated in the annulus of the first stage is cleaned of water droplets using a fine-flow spray catcher. From the fifth stage, the secondary steam through an integrated pipeline enters the heat exchange tubes of the sixth stage of the evaporator. From the tenth stage, the secondary steam through an integrated pipeline enters the heat exchange tubes of the sixth stage of the evaporator. From the tenth stage, the secondary steam is discharged into the capacitor.

 The distillate formed inside the heat exchanger tubes of the stages and in the water heaters moves from the stage to the stage, is self-cooling, and from the fifth stage through a six-stage built-in self-evaporator it enters the tenth stage, where it is mixed with a distillate of 6-10 stages. From the tenth stage, the distillate merges into the tank, where the distillate from the condenser also merges. The resulting saline solution from the ejector is used as a kill fluid and poured into the well to shut it off.

 The required density of saline solution (brine) is achieved by increasing the evaporation time or by performing evaporation in several stages.

 The steam boiler PKN-2M, which is used in the fields to provide heat for shift camps, corresponds to the steam source for the installation.

 The resulting distillate, which in this process is a by-product, can be used to provide boiler houses with feed water, as well as for household and drinking needs.

 The use of the invention simplifies the process of preparing a kill fluid in the form of a saline solution of the required density, since it does not require the cost of transportation, storage and use of salt.

Claims (4)

 1. A method of killing oil and gas wells, including preparing a killing fluid in the form of a saline of the required density and pouring it into the well, characterized in that the saline of the desired density is prepared in a desalination plant, while filtered Senoman water from the intake is fed to its entrance , and the desired density of the saline solution at the outlet of the desalination plant is achieved by increasing the evaporation time or by performing the evaporation in several stages.  2. The method according to claim 1, characterized in that use the desalination plant DOU GTPA-10.  3. The method according to claim 1 or 2, characterized in that the filtering of the original Cenomanian water is carried out from suspensions larger than 0.5 mm and other debris.  4. The method according to one of claims 1 to 3, characterized in that the distillate formed at the outlet of the desalination plant, in addition to the saline solution, is used to provide boiler houses with feed water, for household and drinking needs.