RU2322311C1 - Reservoir with inclined bottom and method for reservoir cleaning of bottom sediments - Google Patents

Abstract

FIELD: oil product transportation and storage, particularly stationery reservoir cleaning.

SUBSTANCE: method involves cleaning reservoir bottom and walls under the action of heated working agent jet in centrifugal force field. The working agent is oil heated up to 60-95°C. Oil jet is acted in centrifugal force field on upper and lower conical inclined bottom bodies. Reservoir comprises body with inclined bottom, working agent supply pipe, pipe for remainder discharge through bottom center. Conical bottom includes upper bottom inclined towards reservoir center from both sides thereof. The inclination angle is 2°-12° in dependence of solid paraffin and asphalt-tar component content in oil. Conical bottom comprises lower bottom inclined at 1°-5° to reservoir center from both sides thereof. The upper and lower bottoms have annular accumulation means with distribution jets extending at 2-5° to inclined conical bottom surface and at 45° to annular manifold surface in the first, counterclockwise direction.

EFFECT: decreased pollutant emissions into environment, decreased reservoir cleaning time, provision of deposit removal during vessel operation without staff access inside reservoir.

3 cl, 2 dwg

Description

The invention relates to the field of transportation and storage of petroleum products and can be used, in particular, for cleaning stationary tanks.

A known method of cleaning the tank from residues of petroleum products, which consists in sending jets of the working agent to the surface to be treated and moving them on the surface, while the working agent used is heated to a viscosity of 4-60 mm ² / s, the residues removed during the cleaning of the tank petroleum products.

The cleaning container contains a bottom, a hollow rod inserted into it with transverse bends with nozzles at the end arranged to allow the jets of the working agent to flow in mutually opposite directions and to provide different forces for the jets to flow out of the nozzles, and the hollow rod is fixed in the opening of the tank with the possibility of rotation with respect to the longitudinal axis of the rod and deviations from the vertical axis of the tank at an angle of up to 45 ° (RF Patent No. 2200067, MKI V08V 9/093, Bull. No. 7 of 03/10/2003).

The known capacity and method of cleaning it does not allow to separate the mud deposits from the pure product.

The closest technical solution (prototype) to the claimed tank is a tank with an inclined bottom with an angle of one-sided tilt of the bottom from 3 ° to 10 ° (Patent No. 1217735, Canada, filed July 30, 1984, published 02.10.87, MKI V67D 3 / 00), including a housing with a conical bottom, a pipe for draining the residue through the center of the bottom, located in the ground, a pipe for supplying a working agent.

A disadvantage of the known technical solution is the danger of freezing of the bottom residue of the watered product in the cold season, since the pipe for removing the residue is in the ground, in addition, the one-sided inclination of the bottom affects the drainage of the residue from the tank, reduces the cleaning performance.

Closest to the proposed invention is a method of cleaning aeration tank from sludge and a device for its implementation / RF Patent 2206416, MKI V08V 9/093, publ. 06/20/2003).

The essence of the invention is to use the field of centrifugal forces created using a special scheme for switching on jet nozzles of the Laval type, into which a part of the treated wastewater is supplied under a pressure of 0.6 MPa with a temperature of 80-90 ° C. The device comprises a housing, a distribution pipe, an annular collector. Jet nozzles are located at an angle of 30 ° to the surface of the collector.

The significant disadvantages of the prototype:

1. Hot water inhibits extraction, i.e. separation of solid paraffins from mechanical impurities of oil sludge (bottom sediment). Solid paraffins along with mechanical impurities are removed from the tank and sent to the sludge collector.

2. Hot water does not flush oil products from the tank walls. For overhaul, it is necessary to steam the tank with water vapor with a temperature of 150-200 ° C for 2-3 days.

The objective of the invention is to increase the productivity and efficiency of cleaning the tank while reducing emissions of harmful substances into the environment.

This problem is solved by the fact that in the method of cleaning the tank from bottom sediments, including cleaning the walls and bottom under the influence of a jet of a heated working agent, in the field of centrifugal forces, according to the invention, oil heated to 60-95 ° C is used as a working agent, the effect of the jet which is carried out in a field of centrifugal forces on the surface of the upper and lower conical inclined bottoms with a bilateral bias towards the center of the tank.

This problem is also solved by the fact that in the tank with an inclined bottom, including a pipe for supplying a working agent, a pipe for draining the residue through the center of the bottom, according to the invention, the conical bottom consists of an upper bottom with a two-sided slope to the center from 2 ° to 12 ° and a lower bottom with a two-sided slope from 1 ° to 5 ° to the center of the tank and at an angle of 45 ° to the surface of the annular collector in one direction counterclockwise.

Figure 1 presents a General view of the tank, figure 2 is a top view.

The device of the tank contains a housing 1, the upper inclined bottom 2 with a slope of 2-12 ° to the center of the tank. The angle of inclination depends on the content of solid paraffins and asphalt-resinous components in the oil. The higher their content, the higher the angle of inclination. The tank contains a lower inclined bottom 3 with a slope of 1-5 ° to the center, a cylindrical pit 4 with a diameter of 4-6 m and a height of 1-1.5 m to collect dirt and water. The tank also contains an upper annular manifold 5 and a lower annular manifold 6, they are designed to supply heated oil and create a field of centrifugal forces under a pressure of 0.3-0.8 MPa using distribution nozzles 7, pipe 8 for supplying oil to the annular manifold, pipe 9 for pumping and pumping oil from the tank, a pipe 10 for drainage of water and dirt from the tank.

The tank is cleaned as follows: oil heated to 60-95 ° C is supplied from the pipe 8 under a pressure of 0.3-0.8 MPa to the manifold 5 and then to the nozzles 7, creating fields of centrifugal forces, and thereby the surface of the inclined surface is completely cleaned bottoms 2. The upper collector is used periodically to flush bottom sediments into the pit 4.

Design parameters of some devices. Nozzles 7 with a nozzle diameter of 10 mm are located on the manifold 5 at a distance of 1.5 m from each other. The nozzle nozzles 7 are mounted at an angle of 2-5 ° to the surface of the inclined conical bottom 2 and at an angle of 45 ° to the surface of the annular collector in one direction counterclockwise. The angle of inclination (2-12 °) of the upper inclined conical bottom 2 contributes to the free flow of sediments and water into the pit 4.

The method using the device is as follows.

As bottom sediments accumulate in the pit 4, oil is completely pumped out of the tank to the funnel pos.11, heated oil is fed into the lower manifold 6 until a uniform fluid mass of the bottom sediment is obtained and discharged through the pipe 10.

Before cleaning in semi-automatic mode, the tank is freed from oil to the level of pos. 11, all hatches are closed, breathing valves and nitrogen are fed into the tank to create an explosion-proof environment inside and reduce harmful emissions into the atmosphere. Then, the heated oil is fed sequentially to the reservoirs 5 and 3. The sediment is pumped out through the pipe 10. Then the tank is started up again, this cycle is repeated annually in the summer.

In the event of a major overhaul, the reservoir is freed from oil and bottom sediments, the solvent falls into the reservoir through collectors 3 and 5 — the oil fraction 170-360 ° C, etc. Water vapor and washed sediment are discharged through pipe 10. Air samples are taken from the reservoir and, in case of positive analysis proceed with repair.

The proposed tank and method of cleaning it can dramatically reduce emissions into the environment, i.e. environmentally safer, cleaning time is reduced by 2-3 times, bottom sediments are removed in the operating mode of the tank. It is possible to carry out cleaning without access for maintenance personnel inside the tank.

Claims (3)

1. The tank with an inclined bottom, comprising a housing with a conical bottom, a pipe for supplying a working agent, a pipe for draining the residue through the center of the bottom, characterized in that the conical bottom consists of an upper inclined bottom with a two-sided slope to the center of the tank 2-12 ° depending from the content of hard paraffins and asphalt-resinous components in oil and the lower inclined bottom with a bilateral slope to the center of 1-5 °, equipped with annular manifolds with distribution nozzles mounted at an angle of 2-5 ° to the surface the conical bottom and at an angle of 45 ° to the surface of the annular collector in one direction counterclockwise. 2. The tank according to claim 1, characterized in that it contains a cylindrical pit with a diameter of 4-6 m and a height of 1-1.5 m 3. A method of cleaning the tank from bottom sediments, including cleaning the walls and bottom under the influence of a jet of heated working agent in the field of centrifugal forces, characterized in that as a working agent, oil heated to 60-95 ° is used, the effect of the jet of which is carried out in a centrifugal field forces on the surface of the upper and lower conical inclined bottoms.

Images