Pulverized coal or water coal slurry gasification furnace system

Abstract

The invention discloses a pulverized coal or water coal slurry gasification furnace system which comprises a gasification furnace, a feeding system for feeding the gasification furnace and a follow-up treatment system of a discharge compound gas, wherein the gasification furnace comprises a combustor and a quench chamber positioned below the combustor; the quench chamber is provided with a downcomer and a quench ring; the quench ring is arranged at the top part of the downcomer and provides quench water; the downcomer comprises an air reduction barrel and an air distribution barrel; the lower end of the air reduction barrel extends to the air distribution barrel; an air diffusion mesh is arranged on a ring-shaped cross section between the air distribution barrel and the air reduction barrel; and the lower edge of the air reduction barrel is in a sawtooth shape. According to the pulverized coal or water coal slurry gasification furnace system, water and ash containing in a synthetic gas in the quench chamber are lightened; the service lives of the quench ring and the downcomer are prolonged; the stable production is kept; the operation period of the gasification furnace is prolonged; and the continuous operation of over baking and chemical engineering feeding.

Description

technical field [0001] The invention relates to a pulverized coal / coal water slurry gasification furnace system. Background technique [0002] Coal is an important energy source. For a long time, the use of coal has been accompanied by serious environmental pollution. In recent years, people pay more and more attention to the clean coal technology aimed at reducing pollution discharge and improving utilization efficiency. Coal gasification technology, as one of the coal processing and conversion technologies, is considered to be one of the most efficient and clean clean coal technologies. [0003] Modern coal gasification technology, especially high-pressure, large-capacity entrained-bed gasification technology has been widely used in industry. In our country, many manufacturers have introduced and used modern entrained bed gasification technology. Modern entrained bed gasification technology is mainly divided into coal water slurry gasification and pulverized coal gasific...

AI Technical Summary

Problems solved by technology

[0010] In addition, when the production load is relatively high, since the annular gap between the riser and the downcomer is relatively narrow, the flow rate of the syngas after leaving the water bath is fast, which is easy to cause the phenomenon of syngas carrying liquid, even if the syngas in the quenching chamber leaves There is a separation baffle in the channel. When the high-speed flowing gas still sweeps away the small liquid droplets on the baffle and carries liquid again, the liquid in the quenching chamber will easily cause the liquid level in the quenching chamber to drop rapidly and cause the gasifier to trip. It is necessary to increase the chilled water supply flow to ensure the liquid level during production, which not only increases energy consumption and waste of water resources, but also suddenly increases the load of the rear system, affecting stable operation

[0011] When the operating temperature of the gasifier is high, the heat load is high and the saturated vapor pressure increases, which will also cause the syngas to carry water into the after-system; Syngas will bypass the lower edge of the riser to form large bubbles and leave the water bath, which will cause fluctuations in the liquid level in the quenching chamber and liquid level alarms caused by fluctuations, and even tripping

[0012] Chinese patent application number 200720103616.7 provides an atomization-submerged gasifier quenching chamber, which is actually not suitable for pulverized coal / coal-water slurry gasifiers, especially for pressurized coal gasifiers, because of its structural Defects are likely to cause the atomizer and atomizing nozzle to be quickly worn out by the strong erosion of high-temperature slag and coal ash, causing rapid damage to the quenching chamber, so that the long-term operation of the gasifier cannot be guaranteed

[0013] In the existing technology, the gasifier often needs to be baked before feeding. For example, before feeding the coal-water slurry gasifier, it is first necessary to use a preheating burner to bake the furnace temperature to around 1200°C. The preheating burner is removed, then the process burner is installed, and the cooling water of the burner is switched, so that the gasifier can start feeding. The temperature of the furnace may drop below 900°C, which will easily cause the failure of feeding and ignition and there will be safety hazards; the operation process of the dry coal pulverized gasifier is cumbersome and complicated. In the cold state, the ignition burner is first started to ignite the combustible gas emitted by it. Then the ignition burner ignites the start-up burner using fuel oil, and the gasifier is baked according to the heating curve. When the temperature and pressure reach the working conditions required by the process, the pulverized coal burner is then fed with chemical materials, such as Shell gasification For the gasification furnace, three different types of burners need to be prepared, and there are many holes in the combustion chamber of the gasification furnace, which is likely to cause safety hazards

[0014] Chinese patent 200910092771.7 proposes a start-up compound burner for coal-water slurry or pulverized coal gasifier. Its design structure is unreasonable. It is air or oxygen, and the ignition electrode and its protective sleeve are installed in the fuel gas channel (also its coal-water slurry or coal powder channel) on the outer wall of the combustion-supporting gas channel. Coal powder distribution in space or atomization of coal-water slurry is uneven, which leads to low gasification efficiency, and also causes uneven heating and scouring of the burner head, which in turn aggravates the partial injection of the burner and the decrease of gasification efficiency , thereby shortening the service life of the burner. In addition, the service life of the ignition electrode protection sleeve will be greatly shortened under the high-speed coal water slurry or coal powder washing; parts, there is a safety hazard

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