SU1313483A1 - Settling tank for purifying petroleum-containing water - Google Patents

Abstract

The invention relates to a technique for cleaning oil-containing and its wastewater and can be used in oil, oil refining and other sectors of the national economy, where waste water is contaminated with oil and oil products, and improves the cleaning efficiency of oil-containing water. The sump includes a tank 1. in the upper part of which is placed a layer of contact mass of oil 2, and cylindrical perforated chambers (PC) 3 are immersed in it, pipeline 4 with water supply nozzles 5, which are placed outside of e.mkost 1 coaxially with chambers 3. The tank contains a pipeline for draining purified water and a device for draining excess oil, which consists of a nozzle 7 and an interfacial level regulator 8. Inside the PC 3 and co-axially with them, jet-forming nozzles 9 are installed, connected to the water inlet pipes and providing the optimal hydrodynamic mode of operation inside the PC 3. 1 3. Section flea, 1 sludge. (L oo with 00 with

Description

The invention relates to a technique for treating oil-containing waste water and can be used in oil, oil refining and other branches of the national economy, where waste water is contaminated with oil and oil products.

The purpose of the invention is to increase the efficiency of purification of oily water.

The drawing shows schematically a sump for purification1 and oily water.

The sump includes a container 1, in the upper part of which a layer of contact mass of oil 2 is placed, and cylindrical perforated chambers 3 are immersed in it, the shells of which are made perforated. The chambers 3 are connected to the pipeline 4 by means of water supply pipes 5, which are located outside the tank 1 coaxially with the chambers 3. The pipeline 6 is disposed at the bottom of the tank 1 for draining purified water. The tank 1 is equipped with a device for the removal of excess oil, which consists of a nozzle 7 and an interfacial level regulator 8. Inside the chambers 3 and co-axially with them, a jet-forming nozzle 9 is installed, connected to the water supply connections 5.

The sump works as follows.

The tank 1 is filled with water and a calculated amount of oil, and then the source water is fed into the pipeline 4. Water through nozzles 5 and nozzles 9 in the form of jets enters the cavities of chambers 3, where circulating water flows are generated, reflected from the bottom of chambers 3. In the zone of jets entering the cavity of chambers 3, a vacuum is created and oil is sucked through the openings of the upper part of the shell chambers 3. The oil entrained in chambers 3 is displaced with the source water, circulates repeatedly in the cavities of chambers 3 and flows in the form of streams through the openings in the lower part of chamber 3 into the oil layer 2. During the circulation process, the source water enriches with oil hard contact, in which water droplets of oil are absorbed by oil coming from tank 1. As is well known, the most favorable conditions for contact water purification from oil are created when water contains 5-25% of oil and a turbulent regime occurs. fluid flow. It has been established that oil is fed into chambers 3 at their upper third of the height, and the liquid (emulsion) leaves at the bottom of chambers 3, which is 2/3 of their height. The water enriched with oil, after circulation through the openings in the lower part of the chambers 3, flows into the oil layer 2, where the process of contact purification of water from oil is carried out.

The oil contained in the water is absorbed by the contact mass 2, and the purified water enters the oil under the buffer zone, in which dynamic

5 upholding. Large particles of oil, entrained by the flow, float and merge with contact mass 2, and water is discharged to the consumer through a perforated pipeline 6. As oil accumulates from the layer

The contact mass 2 is discharged through the pipe 7, and its height at a predetermined value is maintained by means of an interfacial level regulator 8.

Hydrodynamic mode of propagation of the constrained stream of water in the chamber with

 the permeable (perforated) side wall depends on the ratio of the chamber diameter to the diameter of the jet-forming nozzle D, called the degree of freedom, and

Ooh

0 of the ratio of the total area of the holes on the side wall of the chamber to its total surface, called the coefficient 6

Tom permeability.

5 With an increase in the degree of freedom D at

do

Kp const the distance from the jet axis to the chamber wall increases, as a result, the absolute value of if from also increases, and the jet approaches the free space.

Q flooded. In this case, the main part of the energy of the supply jet is spent on the circulation of fluid inside the chamber, creating slight negative drops at the front end and excess static pressure at the rear end.

With a decrease in K const otv

decreases and jet restraint increases. This leads to an increase in the excess static pressure at the rear end of the chamber, which causes a more intense squeezing of fluid from the chamber, and the appearance of a vacuum zone at the front end, which, extending from the jet axis to the side wall of the chamber, contributes to

5 suction of fluid from the tank into the chamber.

Further decrease with K

 const leads to a significant increase in excess static pressure

n at the rear end of the chamber, as a result of which the suction zone is eliminated and only the liquid is squeezed out of the chamber along the entire lateral surface, i.e. the chamber ceases to perform the functions of a mixer.

5 The optimal mode of input and outflow of a jet of source water into the chamber should be considered as the one at which the maximum depression occurs in the zone of water input.

As a result of experimental studies performed for the ratio of 0, 0

within 2.44-85.0, it has been established that the maximum vacuum in the chamber is 5.1-14 N / m with the length of the dilution zone 1 / 3V at 9.5-25.7, tf- 0.03-2 , 0% and f 45-5,5 / Rl, where F / L QL.

These size ratios are recommended when designing a settling tank according to the proposed technical solution, the use of which will improve the cleaning efficiency of oily water due to the fact that the introduction of a jet-forming nozzles into the design of perforated chambers ensures that the source water enters the chambers in the form of jets of specified sizes and parameters, and The hydrodynamic processes inside the chambers in optimal conditions.

Claims (2)

1. A sump for cleaning oily water, including a container with a layer of water one-time mass of oil, cylindrical perforated chambers immersed in an oil layer, a pipeline with water supply pipes, a pipeline for draining purified water, and an oil drain device, characterized in that, in order to increase the efficiency of water purification, the perforated chambers are equipped with coaxially mounted jetting nozzles connected to the water inlet nozzles. 2. The sump according to claim 1, characterized in that the perforated chambers are made with the following ratios of the dimensions of the elements: the ratio of the chamber diameter to the nozzle diameter is 9.5-25.7; the ratio of the total area of the holes on the side wall to the total area of the side wall is 0.03-2.0%; the chamber length I is (4.5-5.5) /, where F ;, Jfqz  - - cross-sectional area of the chamber.