The article deals with two methods for eliminating freezing of injection wellhead fittings. The first method involves removing injected water from the well fitting under long well operation stoppage at negative ambient temperatures. Water is removed and air is supplied through the system of valves (a spring loaded valve and a float valve). When pumping water into the injection well, the float valve closes the access to the environment, and the spring-loaded valve is open for injected water. When the injection process stops, the spring-loaded valve supplies remaining water into the well fittings and the surface part of the water supply line and closes; the float valve opens. Air into the free space of the well fittings is supplied through the float valve thereby preventing the wellhead and the surface part of the water supply line from freezing. The second method is used to prevent the mouth of the injection well from freezing. A device is installed inside the casing, which allows heat to be accumulated in summer and winter. Accumulated heat is used to heat up the mouth when the water injection process stops.

In the present article, the experimental research of electrochemical cleaning of oil-contaminated soil is provided. The decrease of oil concentration in the soil from 1100 mg/kg down to 250 mg/kg at the current density in the range from 22 A/m2 to 174 A/m2 during 90 minutes is shown. It has been established that there is the limit amount of charge required for effective cleaning, which amounted to 0.96·107 coulombs per kilogram of oil. The electrodes placement variant for the proposed method realization in real conditions is described. It is shown that at a voltage between the electrodes about 18 V and the cleaning efficiency of 77% the energy consumption will be 173 MJ/kg of oil.

The article deals with design changes in the existing injection well fittings. Disadvantages of the existing fittings are stagnant zones, considerable height and dimensions which cause problems of thermal insulation leading to rapid freezing of wellhead equipment in winter. At low temperatures, supply lines freeze and fail. The design of small-sized fittings of injection wells was developed. Elastic rubber cords, which absorb pressure caused by ice expansion due to water freezing and prevent rupture of the supply lines, are recommended to use.

No abstract

In recent years, the amount of minerals recovered from the earth interior exceeds their production over the entire past human history. The reserves of some rare elements have been significantly reduced and the demand for them has increased dramatically through the use of new techniques and technologies. The task of developing new types of mineral raw materials from formation waters has become ever more relevant. In the process of formation water preparation during the production of table salt the fluids and heavy brines are obtained, which are suitable for their further use in oil production. The fluid obtained through deferrization of formation water has reduced content of magnesium ions. The use of this fluid makes it possible to increase the mechanical strength of the cement stone, the tightness of the “column-cement stone” contact zone, and to reduce magnesia corrosion.