SU1502047A1 - Method of purifying oil-production waste water - Google Patents

Abstract

The invention relates to the oil industry, in particular, to the treatment of wastewater containing oil, in the conditions of booster pumping stations, group plants, separation units and collection points. The purpose of the invention is to increase the degree of purification. The method of cleaning oilfield wastewater is carried out as follows. A stream of contaminated water discharged from a pre-discharge unit and containing oil droplets is directed to the unit for cleaning. The water to be purified is introduced through a device made in the form of a choke with an adjustable cross section, the front part of which is located in the internal cavity of the pipe, is introduced at a speed of 5-7 m / s with an upward flow to the gas-water interface. In this case, a fine gas phase arises in the flow. Water-polluted oil and gas droplets and gas-oil complexes are carried by a stream beyond the water-gas interface, where, under the influence of molecular contamination forces, they increase in diameter by a factor of ten, thus acquiring the shape of disks. Transfusing through the edges of the pipe into the annular space, clean water flows in a continuous flat jet under the layer of oil, leaving film oil in it that faces the oil layer. Purified water is taken from the lower part of the annular space of the apparatus, and the accumulating oil is extracted from its upper part. 1 ill., 1 tab.

Description

11.) eieiiHe otti (to its to about, to feed the nefydyvysheusche N) ohms, especially iii.Hci ;. wastewater containing oil,. ;. | ...; 1x booster pumping stations, iiii:) Hbi of stops, parts of separation and collection

.r y | 1, -; 1 (I (.

In the case of an increase in steel CnJi CLEANING.

Ia chs 1tezhe 1 stagetava, 1a techno, yugiches: -. schemes; the implementation of the proposed method OCHI gkn sewage.

(dusob is carried out as follows.

The flux of contaminated 1I) density I. (UL. Discharged from a pre-discharge unit 1 and containing Kai; ui oil of size 3–330 µm in coca, 1 184 () mg / l, viscosity 29 cI and ii, of no. 0.886 at 12 ° C, the cleaning is directed to the installation at the stage of

2, operating in single-line capacity of 17,200 m / day.

The water to be purified through the device 3, made in the form of a choke with adjustable cross section, face h, part 1 which is located in the internal self of the pipe 4, at a pressure drop of 0.55 MPa with a flow rate in this section in different Cycle x tests 3.2--5--6.2 - 7.0 7.5 m / s are guided upwardly

Sj

lump to the gas-water interface. At the same time in water at a flow rate of 5 m / s and more in a significant amount (25-45 l / m) a fine gas phase occurs.

Water-borne droplets of oil, gas, and gas-oil complexes with a large supply of excess surface energy: energy are carried by the flow to the water-gas interface, where they increase in diameter under the influence of molecular forces, the transition to films. An increase in free surface energy reduces the transition time. Due to this, the smallest drops of oil are involved in the process, which previously could not participate in it. Transfusing through the edges of pipe 4 into the annular space 5, clean water flows in a continuous stream under the layer of oil, leaving film oil in it that faces the oil layer.

Purified water is taken from the lower part of the annular space of the apparatus, and the accumulating oil is collected from its upper part. The total residence time of water within the contour of the pipe and the annular space is at a different flow rate in the adjacent section of 1.9 minutes.

The method allows the purification of water in several stages, which makes it possible to clean it to any pre-specified degree at low cost.

production. The average oil content in the water at the outlet of the apparatus varies from 40 to 26 mg / l and is minimal (28-26-27 mg / l) at flow rates in the range of 5-7 m / s. The degree of water purification is 99.0%.

The table shows the comparative data of wastewater treatment at different flow rates in the adjacent section of the supply valve.

The table shows that the application of the proposed technology allows to significantly increase the degree of wastewater treatment while simultaneously increasing the speed of the process. The optimum speed range is 5–7 m / s.

Claims (1)

Invention Formula The method of cleaning oilfield wastewater, which includes the supply of source water to the sump by upward flow through a pipe, the upper end of which is located above the level of oil in the sump, with a speed greater than ascent oil droplets, coalescence of oil droplets in the oil layer, removal of oil and purified water in separate streams, characterized in that, in order to increase the degree of purification, the upward flow is introduced into the pipe at a speed of 5-7 m / s in the adjacent with a pipe section of the supply hose. Duration of settling, min. Oil content in water, mg / l; before cleaning after cleaning Effect of cleaning,% 1.91.91.92.4 1840184018401840 28262739 98.4899,098,5497,9 Gas Nesrt