Water-purification station

(Figure # 1) The scheme of the typical water-purification stationWATER PURIFICATION STATION (EN: water treatment station; DE: Wasserreiniqunqsstation; FR: installation d'epuration d'eau; ES: instalacion depuradora de agua; RU: водоочистная станция) is the complex of the equipment for the purification of the waste and superficial waters, which are purposed for the artificial water flooding of the petroleum layers. The water-purification station belongs to the productive water-distribution system. The water-purification station (see the Figure # 1) includes: the pump stations, batcher, mixer, clarifier (settling tank), the reservoir for the clean water, water lines, and other equipment.

The water (riverine, lacustrine) is injected, using the pumps of the station for the first lifting, into the mixer, into which there is delivered from the batcher the necessary quantity of the coagulant, which is assisting the sedimentation of the particles, which are suspended within the water. The water, which has been treated using the coagulant, using the free gravitational flow, arrives into the clarifiers, and then into the sandy filters, where this water is finally purified of the admixtures. For the removal of the sedimented particles from the filter, they flush this filter using the clean water, which is delivered from the bottom upwards. In case of the existence within the waters, besides the mechanical admixtures, of the compounds of the iron, of the water-insoluble salts, and of the petroleum, they introduce into the system of the water-purification station the various equipment, where the water is subjected to the additional treatment, using the chemical reagents and other means (they introduce into the water the inhibitors of the corrosion at the grouped pump stations).

(Figure # 2) The scheme of the water-purification station with the hydrophobic filter
Figure # 2. The scheme of the water-purification station with the hydrophobic filter and flotator:
1 - the manifold assembly;
2 - the reservoir;
3, 4 - the distributive container and the rays;
5 - the layer of the petroleum;
6 - the regulator for the levels of the water and petroleum;
7 - the collector;
8 - the flotation chamber;
9, 10 - the pipelines for the removal of the admixtures and for the delivery of the gas (respectively);
11 - the trough for the discharge of the petroleum.

The purified water is accumulated within the underground reservoirs, from where, using the pumps of the station for the second lifting, is pumped through the trunk water line into the grouped pump stations of the water-distribution system of the petroleum field. The disadvantage of the water-purification station, which has been described, is the contact of the superficial water with the oxygen of the air, which increases the corrosive destruction of the pipes and equipment during the injection of the water into the petroleum horizons. There is more effective the scheme of the water-purification station, where is ensured the insulation of the waters from the impact of the external aerial medium (they are introduced since the end of the 1970-ies). At the water-purification station of this type (see the Figure # 2), the water, which is containing the mechanical admixtures and the droplets of the petroleum, is delivered into the special reservoir, from where this water, in the form of the waterdrops, arrives into the layer of the petroleum.

Within the latter layer of the petroleum, there are retained the particles of the petroleum, and then the waterdrops with the mechanical admixtures, on the account of the difference of the densities, are sedimented into the drainage. The levels of the water and petroleum within the reservoir are regulated. The water, which has been purified of the petroleum, using the free gravitational flow, flows into the reservoir-flotator, into which there is delivered the compressed gas. Within the flotation chamber, the small bubbles of the gas, while they are capturing the mechanical admixtures, rise to the upper part of the reservoir, from where the latter admixtures are removed in the form of the foam. The purified water is delivered into the grouped pump station.