阅读说明：本技术 一种适应苛刻工况的合成气洗涤系统及其工作方法 (Synthetic gas washing system adaptive to harsh working conditions and working method thereof ) 是由 瞿海根 于 2019-10-21 设计创作，主要内容包括：本发明公开了一种适应苛刻工况的合成气洗涤系统及其工作方法,涉及合成气洗涤技术领域。本发明包括气化炉、黑水处理系统、第一级文丘里洗涤器、旋风分离器、第二级文丘里洗涤器、洗涤塔和水泵；水泵通过第二洗涤水进水管与第二级文丘里洗涤器相连通、通过第一洗涤水连接管与第一级文丘里洗涤器相连通、通过气化炉激冷水管与气化炉相连通。本发明实现了含固量高的黑水和含固量低的黑水的分流,显著降低进入洗涤塔黑水的固含量,有效缓解激冷水系统在开停车和正常运行过程中存在的阻塞和磨损问题,提高了激冷水流量的可靠性和激冷室液位的稳定性,降低了由此可能带来的故障停车概率,一级润湿和旋风分离设备,工程实现难度低,可靠性高。(The invention discloses a synthesis gas washing system adaptive to harsh working conditions and a working method thereof, and relates to the technical field of synthesis gas washing. The invention comprises a gasification furnace, a black water treatment system, a first-stage Venturi scrubber, a cyclone separator, a second-stage Venturi scrubber, a washing tower and a water pump; the water pump is communicated with the second-stage Venturi scrubber through a second washing water inlet pipe, communicated with the first-stage Venturi scrubber through a first washing water connecting pipe and communicated with the gasification furnace through a gasification furnace chilling water pipe. The invention realizes the diversion of the black water with high solid content and the black water with low solid content, obviously reduces the solid content of the black water entering the washing tower, effectively relieves the problems of blockage and abrasion of the chilling water system in the processes of starting, stopping and normal operation, improves the reliability of chilling water flow and the stability of the liquid level of the chilling chamber, reduces the probability of fault stopping possibly caused by the blockage and the abrasion, and has primary wetting and cyclone separation equipment, low engineering realization difficulty and high reliability.)

1. A syngas washing system adapting to harsh working conditions is characterized by comprising a gasification furnace (13), a black water treatment system (14), a first-stage Venturi scrubber (01), a cyclone separator (02), a second-stage Venturi scrubber (03), a washing tower (04) and a water pump (05);

the water pump (05) adopts an independent chilling washing water pump or a water pump group consisting of a chilling water pump (05A) and a washing water pump (05B); the water pump (05) is used for pressurizing process washing water, and the water pump (05) is communicated with the second-stage Venturi scrubber (03) through a second washing water inlet pipe (6), communicated with the first-stage Venturi scrubber (01) through a first washing water connecting pipe (2) and communicated with the gasification furnace (13) through a gasification furnace chilling water pipe (12);

the first-stage Venturi scrubber (01) is used for primarily wetting the crude synthesis gas from the gasification furnace (13), and the first-stage Venturi scrubber (01) is communicated with the gasification furnace (13) through a crude synthesis gas outlet pipe (1) and communicated with the cyclone separator (02) through a first scrubber outlet pipe (3);

the cyclone separator (02) is used for preliminarily removing solids in the crude synthesis gas, the top of the cyclone separator (02) is communicated with the side part of the second-stage Venturi scrubber (03) through a cyclone separator air outlet pipe (4), and the bottom of the cyclone separator (02) is communicated with a black water treatment system (14) through a cyclone separator black water outlet pipe (5);

the second-stage Venturi scrubber (03) is used for secondarily wetting the raw synthesis gas, and the second-stage Venturi scrubber (03) is communicated with the side part of the scrubbing tower (04) through a second scrubber gas outlet pipe (7);

the washing tower (04) is used for washing the synthesis gas to remove the solid participating in the synthesis gas, the top of the washing tower (04) is communicated with a washing tower gas outlet pipe (8), the bottom of the washing tower (04) is communicated with a black water treatment system (14) through a washing tower black water outlet pipe (10), and the side part of the low water level is communicated with a water pump (05) through a washing tower bottom chilling washing water outlet pipe (11); and a process washing water inlet pipe (9) is arranged on the side part of the washing tower (04).

2. A syngas scrubbing system adapted to severe service conditions according to claim 1, wherein there are at least 2 process scrubbing water inlet pipes (9).

3. A syngas scrubbing system adapted to severe service conditions in accordance with claim 1 wherein said scrubber tower (04) is provided with trays and demister.

4. The syngas washing system adapted to severe working conditions of claim 1, wherein the cyclone black water outlet pipe (5) is connected to the gasification furnace (13) or connected to the gasification furnace (13) through a pressurizing device.

5. A method of operating a harsh condition syngas scrubbing system as claimed in any one of claims 1 to 4, comprising the steps of:

s01, primary wetting: the synthesis gas in the gasification furnace (13) enters a first-stage Venturi scrubber (01) to be mixed with washing water conveyed by a water pump (05) for wetting, and then enters a cyclone separator (02) through a first scrubber air outlet pipe (3);

s02, secondary wetting: in the cyclone separator (02), most of liquid and solid carried in the synthesis gas are separated under the action of centrifugal force, black water at the bottom of the cyclone separator (02) is conveyed to a black water treatment system (14) through a cyclone separator black water outlet pipe (5), and the synthesis gas and washing water are conveyed to a second-stage venturi scrubber (03) through a cyclone separator air outlet pipe (4) and a second washing water inlet pipe (6) to be mixed, namely, secondarily wetted; the obtained synthesis gas after secondary wetting enters a washing tower (04) through a second scrubber air outlet pipe (7);

s03, washing and removing solids: the synthetic gas is further washed by countercurrent contact between a tower tray and a process washing water inlet pipe (9) in a washing tower (04), most liquid drops are removed through a demister, the synthetic gas basically free of solids is obtained and is output outwards through a washing tower gas outlet pipe (8), and simultaneously the bottom of the washing tower (04) is communicated with a black water treatment system (14) and a water pump (05) through a washing tower black water outlet pipe (10) and a chilling washing water outlet pipe (11) respectively;

s04, chilled wash water supply: washing water in the chilling washing water outlet pipe (11) is pressurized by a water pump (05) and then is recycled in three parts, one part is communicated with a gasification furnace (13) through a gasification furnace chilling water pipe (12) to supply stress cold water, one part transmits the washing water to a first-stage Venturi scrubber (01) through a first washing water connecting pipe (2), and the other part transmits the washing water to a second-stage Venturi scrubber (03) through a second washing water inlet pipe (6).

Technical Field

The invention belongs to the technical field of synthesis gas washing, and particularly relates to a synthesis gas washing system suitable for harsh working conditions and a working method of the synthesis gas washing system suitable for harsh working conditions.

Background

Gasification is still the most effective way to utilize hydrocarbon fuels such as coal in a large scale, high efficiency and clean manner, and is also the leading technology of related chemical engineering processes. The fuel used comprises coal, petroleum coke, asphalt, biomass and even garbage and other generalized hydrocarbon fuels. The entrained flow gasification technology is a mainstream technology in the coal gasification technology due to high production strength and strong environmental protection.

The entrained flow gasification reaction is that coal or other hydrocarbon and oxygen are partially oxidized in a gasification furnace through slurry or pneumatic transmission to generate synthesis gas. The main components of the synthesis gas are hydrogen and carbon monoxide, as well as small amounts of water vapor, carbon dioxide, hydrogen sulfide, methane and nitrogen, trace carbonyl sulfide (COS), etc., and liquid slag consisting of carbon residue and ash in the feedstock. Therefore, to obtain useful and effective synthesis gas (carbon monoxide and hydrogen), it is necessary to reduce the temperature and remove the solids.

The high-temperature synthetic gas from the gasification furnace passes through a chilling or waste heat boiler or a combined process of chilling and heating the waste heat boiler, and enters a synthetic gas wetting and washing system after the temperature is reduced to a saturation temperature corresponding to the pressure of the synthetic gas.

Typical syngas wetting and scrubbing systems are venturi scrubbers, scrubbers and chilled water pumps. The raw synthesis gas from the chilling chamber firstly enters a Venturi scrubber, is mixed and wetted with Venturi feed water, and then enters a washing tower. The syngas is further scrubbed in a scrubber with process water (condensate, high pressure grey water and boiler feed water) to reduce the solids content of the syngas (solids content expected to be less than 1mg/m 3).

The syngas moistening and scrubbing system is internally equipped with internals for removing solids and liquid droplets entrained with the syngas, such as gas distributors, downcomers/risers, trays and defoamers, among others. The synthesis gas and process water are contacted counter-currently at the tray and the scrubbed synthesis gas exits the top of the scrubber. The washed water (black water) contains a large amount of solids carried by part of the synthesis gas, most of the black water is recycled to the gas-forming chilling system (a gasification furnace and a Venturi scrubber) through a chilling water pump for further utilization, and a small part of the black water is discharged to a flash evaporation system.

Problems with typical syngas wetting and scrubbing systems are:

(1) under the operation conditions of poor coal quality, low concentration of coal water slurry, high load and the like, the synthesis gas is easy to carry water, and the wetting and washing effects are poor, so that the synthesis gas carries ash. The ash entrained in the syngas can adversely affect downstream units, such as heat exchanger plugging and reduced heat transfer capacity, increased shift converter pressure differential, and reduced catalyst reactivity.

(2) The solids entrained in the raw synthesis gas from the gasifier are substantially entrained in the black water at the bottom of the scrubber, which therefore contains a significant amount of solids. Because the black water at the bottom of the washing tower is turbulent severely, the black water which deactivates the cooling ring and the Venturi scrubber inevitably carries part of solids, so that the chilling water filter is blocked, the chilling water pipeline, a valve and a pump are seriously abraded, and even a descending pipe is burnt through due to abrasion of the chilling ring; therefore, aiming at the problems, the synthesis gas washing system suitable for the harsh working conditions and the working method thereof have important significance.

Disclosure of Invention

The invention aims to provide a synthesis gas washing system adapting to harsh working conditions and a working method thereof, which effectively enhance the removal effect of the solid carried in synthesis gas by two-stage wetting, one-stage cyclone separation and one-stage washing separation, reduce the amount of the solid carried in a gasification downstream device, realize the shunting of black water with high solid content and black water with low solid content by the wetting of a first-stage Venturi scrubber and the one-stage cyclone separation, obviously reduce the solid content of the black water entering a washing tower by the black water with high solid content at the bottom of the cyclone separator entering a black water treatment device or returning to a gasification furnace, effectively relieve the problems of blockage and abrasion of a chilling water system in the processes of starting and stopping and normal operation, improve the reliability of chilling water flow and the stability of the liquid level of a chilling chamber, reduce the probability of fault stopping possibly caused by the problems, and a first-stage wetting and cyclone separation device, the engineering realization difficulty is low, and the reliability is high.

In order to solve the technical problems, the invention is realized by the following technical scheme:

the invention relates to a synthesis gas washing system adapting to harsh working conditions and a working method thereof, wherein the synthesis gas washing system comprises a gasification furnace, a black water treatment system, a first-stage Venturi scrubber, a cyclone separator, a second-stage Venturi scrubber, a washing tower and a water pump;

the water pump adopts an independent chilling washing water pump or a water pump group consisting of the chilling water pump and the washing water pump; the water pump is used for pressurizing process washing water, communicated with the second-stage Venturi scrubber through a second washing water inlet pipe, communicated with the first-stage Venturi scrubber through a first washing water connecting pipe and communicated with the gasification furnace through a gasification furnace chilling water pipe;

the first-stage venturi scrubber is used for primarily wetting the crude synthesis gas from the gasification furnace, and is communicated with the gasification furnace through a crude synthesis gas outlet pipe and communicated with the cyclone separator through a first scrubber gas outlet pipe;

the cyclone separator is used for preliminarily removing solids in the crude synthesis gas, the top of the cyclone separator is communicated with the side part of the second-stage Venturi scrubber through a cyclone separator air outlet pipe, the bottom of the cyclone separator is communicated with a black water treatment system through a cyclone separator black water outlet pipe, and the cyclone separator black water outlet pipe is connected with the gasification furnace or is connected with the gasification furnace through a pressurizing device;

the second-stage Venturi scrubber is used for secondarily wetting the crude synthesis gas and communicated with the side part of the scrubbing tower through a second scrubber gas outlet pipe;

the washing tower is used for washing the synthesis gas to remove the solid participating in the synthesis gas, the top of the washing tower is communicated with a washing tower gas outlet pipe, the bottom of the washing tower is communicated with a black water treatment system through a washing tower black water outlet pipe, and the low water level side part is communicated with a water pump through a washing tower bottom chilling washing water outlet pipe; and a process washing water inlet pipe is arranged on the side part of the washing tower.

Further, at least 2 process washing water inlet pipes are arranged.

Further, a tower tray and a demister are arranged in the washing tower.

A working method of a synthesis gas washing system adapting to harsh working conditions comprises the following steps:

s01, primary wetting: the synthetic gas in the gasification furnace enters a first-stage Venturi scrubber to be mixed with washing water conveyed by a water pump for wetting, and then enters a cyclone separator through a gas outlet pipe of the first scrubber;

s02, secondary wetting: in the cyclone separator, most of liquid and solid carried in the synthesis gas are separated under the action of centrifugal force, black water at the bottom of the cyclone separator is conveyed to a black water treatment system through a black water outlet pipe of the cyclone separator, and the synthesis gas and washing water are conveyed to a second-stage venturi scrubber through a gas outlet pipe of the cyclone separator and a second washing water inlet pipe to be mixed, namely, secondarily wetted; the obtained synthesis gas after secondary wetting enters a washing tower through a gas outlet pipe of a second washer;

s03, washing and removing solids: the synthetic gas is further washed by countercurrent contact of a tower tray and a process washing water inlet pipe in a washing tower, most liquid drops are removed through a demister, the synthetic gas which basically does not contain solids is output outwards through a washing tower gas outlet pipe, and simultaneously, the bottom of the washing tower is respectively communicated with a black water treatment system and a water pump through a washing tower black water outlet pipe and a chilling washing water outlet pipe;

s04, chilled wash water supply: the washing water in the chilling washing water outlet pipe is pressurized by a water pump and then is recycled in three parts, one part of the washing water is communicated with the gasification furnace through the gasification furnace chilling water pipe to supply stress cold water, one part of the washing water is transmitted to the first-stage Venturi scrubber through the first washing water connecting pipe, and the other part of the washing water is transmitted to the second-stage Venturi scrubber through the second washing water inlet pipe.

The invention has the following beneficial effects:

(1) the invention effectively enhances the removal effect of the solid carried by the synthesis gas and reduces the amount of the solid brought into a gasification downstream device by two-stage wetting, one-stage cyclone separation and one-stage washing separation.

(2) The black water with high solid content at the bottom of the cyclone separator enters the black water treatment device or returns to the gasification furnace, so that the solid content of the black water entering the washing tower can be obviously reduced, the problems of blockage and abrasion of the chilling water system in the processes of starting and stopping and normal operation are effectively solved, the reliability of chilling water flow and the stability of the liquid level of the chilling chamber are improved, and the probability of fault stopping possibly caused by the problems is reduced.

(3) The added primary wetting and cyclone separation equipment has low engineering realization difficulty and high reliability.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an embodiment 1 of a syngas scrubbing system adapted to severe operating conditions according to the present invention;

FIG. 2 is a schematic structural diagram of an embodiment 2 of a syngas scrubbing system adapted to severe operating conditions according to the present invention;

FIG. 3 is a flow chart of the steps of a method of operation of a syngas scrubbing system of the present invention adapted to harsh operating conditions;

in the drawings, the components represented by the respective reference numerals are listed below:

1-a crude synthesis gas outlet pipe, 2-a first washing water connecting pipe, 3-a first washer outlet pipe, 4-a cyclone separator outlet pipe, 5-a cyclone separator black water outlet pipe, 6-a second washing water inlet pipe, 7-a second washer outlet pipe, 8-a washing tower outlet pipe, 9-a process washing water inlet pipe, 10-a washing tower black water outlet pipe, 11-a chilling washing water outlet pipe, 12-a gasifier chilling water pipe, 13-a gasifier, 14-a black water treatment system, 01-a first-stage venturi washer, 02-a cyclone separator, 03-a second-stage venturi washer, 04-a washing tower, 05-a water pump, 05A-a chilling water pump and 05B-a washing water pump.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "bottom," "top," "side," "inner," and the like are used merely for convenience in describing and simplifying the invention, and do not indicate or imply that the referenced components or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be considered as limiting.