Use of Formation Water and Associated Gases and their Simultaneous Utilization for Obtaining Microelement Concentrates Fresh Water and Drinking Water
Authors: Mamatkulov Makhkam , Mamatkulov Mashal , Gulamov Ikrom 
Published: July 2019

Abstract Purpose: The invention relates to the oil industry, inorganic chemistry, in particular, to the methods of complex processing of formation water, using flare gas of oil and gas field as fuel for producing enriched concentrates of iodine, bromine, magnesium and valuable trace elements, as well as desalinated water (technical and drinking water). The technology includes pre-cleaning of formation water from mechanical impurities and oil using adsorbents, followed by evaporation of water under vacuum, condensing water vapor in the barometric condenser, using of condensed water vapor as the coolant, using of saline water as a coolant of hot water coming out of the barometric condenser to 15–20 °C. The novelty of the design?: The novelty of the design is to get a comprehensive treatment of formation water, using flare gas of oil and gas field as fuel for obtaining enriched concentrates of iodine, bromine, magnesium and valuable trace elements, as well as desalinated water (technical and drinking water). Recycling of formation water with this method considers new directions. Worldwide the patents were received for constructing chemical plants for producing cheap food salt, killing fluid for oil wells, iodine, bromine, hydrochloric acid, caustic soda, sodium sulfate, sodium chloride, potassium bromide, sodium bromide, borax, boric acid, phosphoric acid, lithium carbonate, lithium phosphate, borax, boric acid, ammonia and carbonate products, potassium chloride, bromide and products LiCl, alkali rare elements, uranium, etc.

Hundreds of plants are engaged in the processing of brines in the world, but due to the large content variety of raw materials for each company developed its own individual process steps, depending on the climate or nearby sources of cheap heat. This is due to the fact that for concentrating and isolating the salts removal of a large mass of water required. Therefore, all businesses usually do not produce a particular product, but try to all the useful chemical elements alongside with secondary products - metals, chlorine, bromine, etc. All plants use successive allocation scheme of used salts may vary greatly from each other depending on the primary composition of the brine.

An important advantage of groundwater as a raw material source of rare elements are: the low cost of the product, because groundwater is a grade raw material, some of its geochemical types have relatively high adaptability, besides exploitation of rare elements water deposits does not require expensive mining. So in most countries (United States, Italy, Israel, Japan, New Zealand, Iceland, Australia, etc.) technological research to develop methods for extracting these elements from specific geochemical types of natural waters are constantly and systematically conducted. Cleaning the reservoir water: The technology includes pre-cleaning of formation water from mechanical impurities and oil using adsorbents. Cleaning is carried out in order to separate the unnecessary substances (organic substances) for a concentrate. Organic substances with high concentration cause by negative effects under using a concentrate and are considered to be hazardous substances in fresh water. Getting technical and drinking water and concentrate?: This technology helps to solve issues on providing facilities and public by technical water and are urgently needed, especially in those areas where there are sufficient amounts of formation waters and flare gases resources. The authors of the project developed a way for using flare gas and reservoir water for drinking water treatment and concentrates for medicine. The advantages of this technology?: Thanks to Tashkent State Technical University scientists an improved vacuum evaporation plant, was developed to split reservoir water 2 fractions - for distillate and concentrate. The advantage of this plant is that it works at lower boiling temperatures. This fact has a positive effect on the process of evaporation. Process takes place with low fuel consumption and lack of scale on the inner surfaces of the plant, since it is operated at temperatures not exceeding the limit scaling. Moreover, a significant part of the energy consumed in this process, is formed during combustion of existing flare gas, which leads to cheaper cost of the products. Using the results of this project, the production of a concentrate rich in iodine, bromine, magnesium and other minerals, as well as technical and drinking water will be ensured.

Recycling formation water and separating necessary useful from its structure we can get low cost products, as well as improve the environmental situation. In addition, solving problems with providing with of water is urgently, especially in those areas where there is sufficient amounts of formation water and flare gases resources. Water scarcity is felt in more than 40 countries (estimated at the beginning of the 21st century will reach 120–150 √ 109 m3 per year). Nearly a billion people in the world suffer from a lack of clean drinking water. This deficit can be covered by desalination of saline (salt content of more than 10 g/l) and saline (2–10 g/l) of ocean, sea and groundwater reserves totaling 98% of all water on earth.

Currently, one of the areas of energy is an efficient search of alternative methods to the traditional technologies of desalination of saline and brackish water that is the development of desalination methods of electro- spray nozzles and with subsequent evaporation and condensation. The authors of the project developed a way to use flare gas and reservoir water for drinking water treatment and concentrates.

Another advantage of the technology is solving environmental issues. These environmental problems exist in the areas where flare gases is burnt more million tons per day. Flare gas contains sulfur compounds. Sulfur compounds influences negatively on man and nature. Before the use, flare gas is purify led from compounds of sulfur, moreover, a boiler used in the technology helps complete combustion of flare gases. As a result, of flare gas, full burning decreases a rate of waste gases in the atmosphere. Technical and economic advantages of technology: The developed technology has several technical and economic advantages extraction formation water does not require much cost to obtaining it, produced water gets oil and condensates, and separated from them as by water, oil and gas fields also present flare gases of low pressure. Flare gases can be used as a source of thermal energy concentration - the result of the evaporation process of saline salty water. In addition, the next to the field “South Kemachi” there is a pond of salt water (lake “Devhona”). In the technology it is used as a coolant. In this region, there is the scarcity of fresh water. It should be noted that obtaining a concentrate rich in trace elements, from mineral water from underground using this technology is considered to be cheap raw materials and of low cost.

Lack of technologies that allow effectively utilize APG (gases rich in heavy hydrocarbons, that complicates their pumping through pipelines). Remoteness of potential markets from oil locations. Construction of pipelines to transport the petroleum to plants requires much capital investments, 1 km of the pipeline will cost more than $ 1.0 million to transport APG gas to processing enterprises from remote fields increase the cost of associated gas.

Associated petroleum gas can be used by the subsoil user as fuel in order to heat and electricity in the manner prescribed by the legislation in the field of gas and electricity and in compliance with applicable statutory rules of industrial and environmental safety.

The feature of the field “South Kemachi” is the high content of hydrogen sulfide in oil and associated petroleum gas (APG). As part of APG volume fraction of hydrogen sulfide it is about 2%. Without prior purification of hydrogen sulfide is not possible to use APG for production needs of the field and in this case the only acceptable way of dealing with it is APG flaring. Consumption of crude APG production on the deposit site is not possible. Gas contaminated with hydrogen sulfide when it is used as fuel for the boiler with prolonged exposure can lead to hydrogen embrittlement, cracking sulfide stress and/or cracking under stress corrosion in iron alloys, in other words, to a rapid deterioration of equipment.

In this project the authors consider purification associated gas from hydrogen sulfide in order to use APG purified for use as fuel for a iodine-bromine-magnesium concentrate and desalinated water and gas condensate of the field of formation water, significantly reducing the pollutants and greenhouse gases (GHG) into the atmosphere.

Reduction GHG emission achieved by the volume of natural gas, as well as in a much more complete oxidation of methane using APG as fuel compared to flaring. Flares of the deposits provide a so-called smoke spot flaring characterized by a high coefficient of unburnt gas, which leads to the release of a significant amount of methane in to the atmosphere.

Purification of hydrogen sulfide chemicals is costly.

Boiler for of desulfurization. It makes sense to include this boiler in the project due to the fact that APG is burned with total oxidation. Therefore, due to the work of the boiler methane emissions are reduced compared to flaring.

In the technology barometric condenser is used to create the vacuum that receives the amount of vapor generated by concentrating the solution and evaporation of cooling water. Certain part of the barometric condenser condensate is brought refrigerator X -1 which is the bottom of the lake “Devhona.” cooling fresh water from the cooler X-1 is brought to the barometric condenser. These regions, are short of fresh water for cooling. It is required to develop new methods for cooling.

Reservoir coolers were designed and constructed at Smolensk, Kursk, Chernobyl, South Ukrainian, Khmelnitsky, Kostroma NPP, and Surgut GRES Berezovsky; a cooling reservoir on the basis of natural lakes and depressions is in: Kalinin NPP.

A the construction of such facilities in areas where there is a lack of cooling water is very important. Recently, the amount of industrial cooling water has been increased significantly, so penetrate existing and develop new cooling methods.

Lake water have different temperatures at different depths (10 to 25 °C on the surface of 30 to 40 °C at a depth of 1 m and from 40 to 60 °C at a depth of 1.5 m). In deeper layers, the temperature is lowered at a depth of 10 m up to 18–20 °C.

In the salt lakes several types of vertical thermal structure are observed. Salt lake is a reservoir with a capacity of warm water layer between two layers of colder. In some lakes may be two “hot” zone. Often “hot” area is located in the bottom layer and in this case the vertical thermal structure of the lake consists of an upper “cold” zone and the lower “hot” as it was observed in the lake. Vanda (Antarctica), Solarium Lake Elat (Israel), in some lakes Kulunda steppe, on the Crimean peninsula, the Karakum (Dzens-Litovsk, 1957) and on the lake. Sassykkul the Eastern Pamirs (Egorov, 1991).