Water intake and desalination plant (OZ) facilities occupy the construction territory located on the coast of the Caspian Sea between the cape Rakushechny and Tokmak.

Administratively, the construction area is located in the Karakian district of Mangistau region. Zhanaozen is located 65 kilometers north-east of the OZ site.

The following water treatment system is required to ensure that the required water quality is achieved within the range of the values of the source water.

Initial sea water by pumps of the pumping station of the 1st rise is supplied to the pressure radial flotation units with saturation units - 6 units (5 working, 1 standby), to remove from the water suspended particles actively rising in the process of drainage saturated water. In order to improve the flotation process and increase the efficiency of water purification, pre-reagent treatment has been adopted.

After the flotation, water is fed to a coarse mechanical filtration unit (disk filtration systems) - 5 plants (4 working, 1 standby), where large suspended particles larger than 200 μm are cleaned. The washing is carried out by reversing the current of the purified water for 10 to 30 seconds.

Then partially illuminated water is supplied to ultrafiltration modules - 7 plants (6 workers, 1 backup). At the ultrafiltration stage, the main part of dissolved organics, silicon and colloidal particles is removed and the turbidity and color of water is reduced. The units are equipped with a pump station for reverse washing, a set of dosing stations for alkaline and disinfecting washing and tanks with a volume of 2x210 m3 for carrying out the reverse washing of ultrafiltration membranes.

The ultrafiltrate is supplied by pumps to the reverse osmosis plants of 1 stage - 6 units (5 working, 1 standby). Before osmosis, a solution of the hardness salt sediment inhibitor, an anti-scalant, is introduced into the water, which prevents back-osmotic element contamination and reagents that improve the quality of water purification (boron removal).

The units of the first stage of the reverse osmosis plant are provided according to the one-stage scheme of the reverse osmosis installation. Each unit is equipped with a high-pressure pump (38 bar) and anti-scalant dispensing unit. Part of the permeate of the first stage is directed to the mineralization line, the remaining flow is directed to the second stage of reverse osmosis.

The second stage units of the reverse osmosis plant are provided by a two-stage reverse osmosis plant scheme for deeper desalination and removal of excess salts. The second stage permeate of reverse osmosis together with the first stage permeate flow is fed to demineralization. The concentrate of the second stage is fed to the entrance of the first stage..

Acid and alkaline wastewater formed during chemical membrane regeneration (ultrafiltration and reverse osmosis), are diverted to the sediment shredders for neutralization with conical bottoms - 4 pieces (2 working, 2 reserve). Neutralized and purified washing water is directed to the head of the plant, the sediment remaining in the conical part of the sediment trap is pumped out with silage and taken for disposal.

After the second stage of reverse osmosis, water enters the mineralization unit - 1 set of 20 pieces. The process of demineralization is necessary to bring desalinated water to drinking quality. In order to avoid the corrosive effect of permiate on the pipe material, an alkali (sodium hydroxide) process is provided at the outlet of the water plant to increase the water pH to 6-8.5.

After the mineralization unit, the desalinated water is discharged into drinking water tanks with a capacity of 2x2000 m3..

Disinfection and disinfection of water is provided by a solution of sodium hypochlorite. A solution of sodium hypochlorite for disinfection is dosed in front of drinking water tanks.

The quality of the inlet water, the outlet water and the degree of purification of the membrane unit is measured by means of an electrical conductor sensor and a conductometer installed in the water quality control unit.

After desalination and decontamination, water from drinking water tanks is pumped by the pump station II rise to the main water supply.