RU2386897C2 - Parfyonov flame device - Google Patents

Abstract

FIELD: power industry.

SUBSTANCE: flame device for smoke free combustion of gases includes a head, movable gas damper in the form of flow-around body, which is capable of changing flow passage of the head when gas consumption changes and creating gas jets, passages between the head housing and gas damper to combustion zone for gases of low pressures or other pressures, constant or other consumptions. Gas damper(s) is(are) lifting and/or rotary in number of 1+n (where n from 0 to 10000 and more), has(have) the shape(s) of either a pin, or a plate, or a cone, or a prism, or a flowing body with the length exceeding the width, or a sphere with possibility of keeping design velocity(ies) of effluence of flame gases from heads, and formation of gas jets, including either flat, and/or open, and/or diverging in various directions and contacting the air on both sides.

EFFECT: invention allows providing smoke free gas combustion within the whole design range of flows of flame gases without forced supply of air or water vapour, or water owing to increase of specific contact surface of ambient air and gas.

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Description

The invention relates to a device for flare installations and can be used in the oil and gas, petrochemical, chemical, coke and other industries for the thermal neutralization of gases when it is impossible to utilize them in technological processes and / or their emergency discharge into the atmosphere.

Environmental legislation requires that gases be burned smokeless (without soot) and with a minimum content of carbon monoxide (CO) in the products of combustion.

The designs of the flare head are widespread, which are a sawn-off shotgun of a round flare pipe, on the circumference of which stand-by burners are placed. On the heads may be devices for supplying steam and / or air and / or water.

The design flaw is that in order to obtain smokeless combustion of the exhaust gas, a large quantity of air or / and water vapor or / and water must be forced to supply a large amount of smoke to the flare burner (II Strizhevsky, AI Elnatanov. “Flare units”. - M: Chemistry, 1979, pp. 38-41). However, water vapor or water that evaporates in a flame suppresses combustion (they are inert like nitrogen, helium, carbon dioxide, etc.), reduce the temperature in the flame plume below the cracking temperature, which stops the formation of soot, but the flame gases no longer burn.

Closest to the application, in technical essence, is the design of a flare head for smokeless combustion of gases (patent for ПМ RU No. 36876), consisting of a housing and a movable gas shutter in the form of an inverted “glass”. In case of emergency discharges with increasing gas pressure to the calculated value, the “glass” begins to rise and release flare gases to the upper part of the head.

The design drawback is that large and emergency gas discharges cannot be completely burned, since the head forms flare gases in a jet having a closed circular cross-section in cross section with reduced pressure inside and contracting to the central axis, with a minimum contact surface with air. In addition, the bottom of the "glass" creates a large gas-dynamic resistance during emergency discharges, which prevents the use of such heads on special flare systems (low pressure) and leads to an unjustified increase in its dimensions.

The objective of the invention is the creation of designs of flare plants smokeless (complete) combustion of gases in the entire estimated range of flow rates of flare gases without forced supply of air and / or water vapor, and / or water by increasing the specific surface area of contact with ambient air / gas and achieve their mixing (up to stoichiometric coefficient and more).

The problem is solved in that the flare installation of smokeless combustion of gases, containing a head, a movable gas shutter in the form of a flow body, which is able to change the cross-section of the head when the gas flow rate changes and creates gas jets, passages into the combustion zone between the head body and the gas shutter into the combustion zone for low pressure gases or other pressures, fixed or other flows. According to the invention, the gas (s) shutter (s) is made of lifting (s) and / or rotary (s) in an amount of from 1 + n (where n is from 0 to 10,000 or more), has (s) shape (s) in the form or a rod, or a plate, or a cone, or a prism, or a streamline body with a length exceeding the width, or a sphere, with the possibility of maintaining the calculated velocity (s) of the outflow of flare gases from the heads and creating gas jets, including or flat and / or open and / or diverging in different directions and in contact with air on both sides, in a cross section of a minimum thickness s - maximum perimeter which are obtained at a flow of gas moving the gate (hereinafter gates). Movable shutters provide the estimated velocity of the flow of gases from the heads. To reduce the dimensions of the heads for high gas flows, the gates in the form of plates, the arrangement of the faces of the polyhedra can be made so that the gas jets are not closed along the perimeter of the cavity, but are open, providing contact of the jets with the surrounding air on both sides (gas jets and their combinations should have a cross section, for example, in the form of S, E, W, II, H, P, X, star-shaped, etc.). These jets of gases can diverge in different directions (at an angle to the axes of the heads and flare barrel), which increases the cross-section of the capture of ambient air and ensures complete combustion.

When the gas shutter is in the lower (closed) position, operation problems arise from pressure back-up from the flare system to the equipment in preparation for repair, therefore, it is preferable that the heads have openings in the combustion zone for low-pressure gases, constant or other minor costs. Minor gas consumption (constant shutter, process purge, etc.) can enter the combustion zone through the design gaps between the head body and the gas shutter. Jets of gases with low speeds, but thin or flat, with a high specific surface mix well with air and burn smokeless.

It is possible to supply gases to the combustion zone from various other flare systems.

Each valve combination configuration is designed for its own range of gas flow rates and pressures. An industrial enterprise can have up to several thousand safety valves (PCs) from various process units that have exhausts into one flare system. When one or more PCs are triggered, the pressure in the flare system should increase slightly, which is ensured by opening on the head (s) of one or more gates of the minimum throughput (rod and / or spherical and / or conical). With an increase in gas consumption and an increase in pressure in the flare system, gates (lamellar, and / or prismatic, and / or flow bodies, etc.) open on the head (s), designed for large: throughputs and pressures. Depending on the calculated gas flow rates, the gates may have a length greater than the width. It is possible to eject gases of high speeds into the combustion zone of gases from other flare systems with lower pressure (from parallel and / or coaxial flare shafts).

Movable butterfly valves can have various designs, the simplest of which are spheres or cylinders with through holes, which in the closed position are covered by the shells of the heads. The increase in gas pressure in the flare barrel (by a known actuator, for example, a piston with a balancing spring) moves the piston and, through a mechanical rod with a lever, transfers force to the butterfly valves, which rotate and open the passage openings. When the gas pressure decreases, the spring returns the piston and the valves to their original closed position.

More complex butterfly valves can be lamellar, in the form of blinds, which also change the bore sections of the upper ends of the FU heads. On one FU at the same time there may be heads with the design of lifting and butterfly valves.

Gate actuators can be pneumatic, solenoidal, spring, gravity and any known, including combinations thereof.

The drawing shows the operation of the flare unit, which implements a method of smokeless burning of gases of variable compositions, flow rates and pressures of flare systems of various pressures without forced supply of air and / or steam and / or water to the gas combustion zone.

Coaxial PS 1 through a separate passage 2 from the flare system receives combustible high-pressure gases 5. Gases from the flare systems of low pressure enter combustion through separate passages 3, 4, (... N). The upper part of the passage 2 ФУ 1 has a head (s) 6 together with a shutter 8, directing and forming flat jets of combusted gases 7. The gas outlet through the head (s) 6 is closed (in the absence of a gas flow 5 from the flare unit) with a movable gas shutter (regulating lifting and / or rotary device) 8. The drawing shows the simplest particular case when the shutter is made. With an increase in the flow of gases 5, the pressure under the shutter 8 increases and it rises with an increase in the gap between the head 6 and the movable part — the shutter (the lower position is indicated by a dotted line). An increase in gas pressure leads to an increase in the geometric dimensions of the gas stream, the contact surface of the gases with the surrounding air, and turbulence. The jets of high-pressure gases 7 interact with the jets of low-pressure gases 9.10 (... N), eject them and discharge the latter at high speed into the mixing zone with the surrounding air and combustion. The pressure under the valve is controlled by a load 11 (gravity method) with a thrust 12 (or any other known drive). To enable the combustion of gases with low costs (for example, constant costs and constant process discharges) and low pressures, passages 13 are provided by the shutter 8 (in the lower position) to the combustion zone.

Thus, smokeless gas burning is ensured in a flare unit without forced supply of air and / or water vapor and / or water.

Claims (1)

A flare smokeless gas combustion installation containing a head, a movable gas shutter in the form of a flow body, which is able to change the cross section of the head when the gas flow rate changes and creates gas jets, passages between the head body and the gas shutter into the combustion zone for low pressure gases or other pressures, fixed or other costs, characterized in that the gas shutter (s) are made of lifting (s) and / or rotary (s) in an amount of 1 + n (where n is from 0 to 10,000 or more), has (s) shape (s) in the form of either a rod or plates or a cone, or a prism, or a body flowing over a length exceeding the width, or a sphere with the possibility of maintaining the calculated velocity (s) of the outflow of flare gases from the heads and creating gas jets, including either flat and / or open, and / or diverging in different directions and in contact with air from two sides.

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