JPH0311218Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a coal gasification device, and particularly to a coal gasification device suitable for reducing the amount of dust scattered from the reactor body and unburned carbon in the ash extracted from the gasifier. The present invention relates to a gasification device.

A conventional coal gasification method will be explained based on FIG. 1. Coal 2 supplied to reactor 1 is gasified in the spouted bed by steam and air (or oxygen) supplied from steam line 3 and air line 4, respectively. A part of the coal (char) scattered from the reactor 1 is recovered by the first cyclone 5 and is supplied to the reactor 1 again from the chir supply line 5A. The fine dust that is not collected by the first cyclone 5 is collected and recovered by the second cyclone 6. The dust collected by the second cyclone 6 is finely divided and has been cooled during the cyclone collection process, so even if it is supplied to the reactor 1 again, it will rise in the spouted bed and remain unreacted. It is discharged outside the system. Therefore, the overall gasification efficiency of the dust gasification reaction cannot be improved. Further, when the collected dust is taken out of the system and reprocessed, the processing is extremely troublesome because the dust is in a fine form. On the other hand, the ash produced in the reactor 1 is extracted from the reactor 1 and recovered, but this ash contains unburned carbon. Discharging this unburned carbon to the outside of the system is extremely inconvenient in terms of the gasification efficiency of the entire system.

The purpose of this invention is to effectively utilize the dust scattered from the reactor and the ash extracted from the reactor in the gasification reaction, and to improve the gasification efficiency of the entire gasification device. Our goal is to provide the following.

In order to achieve the above object, the coal gasifier according to the present invention is provided with a gasifier and a combustion furnace that performs high-temperature combustion using oxygen in order from the upper stage. a reactor main body provided with a supply section for supplying dust, a first collector that collects the dust scattered from the reactor main body, and a first collector that collects the dust that has passed through the first collector. a second collector, a chiar supply line that supplies the chir collected by the first collector to the gasifier, and a chir supply line that supplies the dust collected by the second collector to the combustion furnace. a dust supply line, the combustion exhaust gas generated in the combustion furnace is formed so as to be introduced into the gasification furnace through a communication passage, and
A line is provided for extracting the ash produced in the gasifier independently from the communication path and guiding it to the combustion furnace.

In short, after collecting the fine dust with low reactivity scattered from the reactor, this collected dust is introduced into the combustion furnace installed in the lower stage of the gasifier, where it is combined with the ash extracted from the gasifier. By burning, the dust and unburned carbon in the ash are effectively used for the gasification reaction, and the clinker-like ash produced in the combustion section is efficiently taken out of the device.

Further, by forming a line that takes out ash from the gasifier and leads it to the combustion furnace independently of the communication path that leads the flue gas generated in the combustion furnace to the gasification furnace, it is possible to contain unburned carbon. The ash in the gasifier (800-900℃) is converted into a combustion furnace (1500-1600℃)
This makes it possible to smoothly guide the inside of the body. As a result, unburned carbon in the ash can be used stably and effectively in the gasification reaction, and the coal utilization rate and gasification efficiency can be improved.

An embodiment of the present invention will be described below with reference to FIG.

This gasifier is mainly composed of a reactor body 11, a first cyclone 12, and a second cyclone 13, and the reactor body 11 is composed of a carbonization furnace 14, a gasification furnace 15, a combustion furnace 16, and a clinker recovery furnace 17. has been done.

The carbonization furnace 14 is provided with a coal supply port 18 , and the carbonization furnace 14 and the gasification furnace 15 are partitioned by a dispersion plate and communicated with each other by a chiar lift pipe 19 . A chir supply port 20 is provided on the side of the gasifier 15 and is connected to the first cyclone 12 by a chia supply line 12A. A dust supply port 21 is provided on the side of the combustion furnace 16 and connected to the second cyclone 13 by a dust supply line 13A. It is connected to an ash extraction pipe 22 provided independently from the ash removal pipe 22. Although not shown, the combustion furnace 16 is provided with a supply section that supplies air (or oxygen) for combustion.

A dispersion plate 23 is provided at the bottom of the gasifier 15, and air (or An oxygen) supply port 24 and a steam supply port 25 are provided. The gasification furnace 15 and the combustion furnace 16 are communicated through an exhaust gas transport pipe 26. The clinker recovery furnace 17 is provided with a water supply port 27 and a slag discharge port 28 .

In the coal gasification apparatus having such a configuration, coal is supplied to the carbonization furnace 14 from the coal supply port 18, and the coal produced during carbonization of the coal is transferred to the gasification furnace 1 through an overflow pipe (not shown).
5, and the chir scattered from the top of the carbonization furnace 14 passes through the line 14A to the first cyclone 12.
After being collected, the gas is supplied into the gasification furnace 15 from the chir supply port 20 via the chir supply line 12A. The char thus supplied into the gasifier 15 is gasified by air or oxygen and steam introduced from the air (or oxygen) supply port 24 and the steam supply port 25, respectively.

The dust not collected by the first cyclone 12 is led to the second cyclone 13, where it is collected and then supplied into the combustion furnace 16 from the dust supply port 21 via the dust supply line 13A. On the other hand, the ash produced in the gasifier 15 is supplied into the combustion furnace 16 through an ash extraction pipe 22. In the combustion furnace 16, the char and ash are burned at high temperatures by oxygen, resulting in the ash becoming slag. Water introduced from the water supply port 27 is stored in the clinker recovery furnace 17, where the slag-formed ash is rapidly cooled and becomes clinker. The combustion exhaust gas mainly consisting of carbon dioxide gas (CO ₂ ) generated in the combustion section 16 rises in the exhaust gas transport pipe 26 and is introduced into the gasifier 15, where it is used as a gasifying agent. Therefore, the sensible heat of the combustion exhaust gas is effectively utilized as it is in the gasifier 15. This point will be explained in detail. According to the present invention, the dust supplied through the dust supply line 13A and the ash that is stably supplied independently and without passing through the ash extraction pipe 22 through the exhaust gas transport pipe 26. It is combusted with combustion air (or oxygen) in the combustion furnace 16, and the unburned carbon in the dust and ash is combusted and converted into combustion exhaust gas containing _CO2 as a main component. The reaction that generates CO ₂ is an exothermic reaction, and therefore, CO ₂ is generated by the combustion of the unburned carbon, and the temperature of the generated combustion exhaust gas itself easily rises to a high temperature (1500 to 1600°C). Become. Then, the combustion exhaust gas that has become efficiently heated in this way is directly supplied into the gasifier 15 through the exhaust gas transport pipe 26. In the gasifier 15, a gasification reaction in which CO and H ₂ are produced is carried out by gasification steam and air supplied from the steam supply port 25 and the air supply port 24. This reaction is said to occur most easily at around 800-900°C.

On the other hand, when the combustion exhaust gas mainly composed of CO ₂ generated in the combustion furnace 16 is introduced into the gasification furnace 15, CO is generated in the following reaction.

C+CO ₂ →2CO (1) This reaction (1) has a fast reaction rate, but it is difficult to occur below 1000°C, and since it is an endothermic reaction, a higher temperature is required. According to the present invention, as mentioned above, high temperature (1500 to 1600℃)
Since the CO ₂ is introduced into the gasifier 15, the above reaction (1) proceeds smoothly instantly, and also at a high temperature.
Since CO ₂ (1500 to 1600°C) can be obtained efficiently by supplying only CO ₂ for combustion, the overall gasification efficiency is improved. In other words, CO can be generated from the unburned carbon in the dust and ash, and the sensible heat of the combustion exhaust gas mainly composed of CO ₂ can be directly used in the reaction (1) above in the gasifier. It can be effectively used for heat, and the overall coal utilization rate and gasification efficiency can be improved.

As described above, according to the present invention, the dust scattered from the reactor and the ash extracted from the gasifier are burned in the combustion furnace, so that the unburned carbon in the dust and ash is effectively used for the gasification reaction. This will dramatically improve the efficiency of gasifiers.

[Brief explanation of the drawing]

FIG. 1 is a flowchart of a conventional coal gasification method, and FIG. 2 is a schematic diagram showing an example of the present invention. 11... Reactor main body, 12... First cyclone, 1
3... Second cyclone, 14... Carbonization furnace, 15... Gasification furnace, 16... Combustion furnace, 17... Clinker recovery furnace, 1
8... Coal supply port, 20... Chir supply port, 21... Dust supply port, 22... Ash extraction pipe.

Claims (1)

[Scope of utility model registration request] From the top, a reactor main body is provided with a gasification furnace and a combustion furnace that performs high-temperature combustion using oxygen, and a supply section that supplies steam and air or oxygen for gasification to the gasification furnace; A first collector that collects dust scattered from the container body, a second collector that collects dust that has passed through the first collector, and dust collected by the first collector. The combustion exhaust gas generated in the combustion furnace is provided with a chir supply line that supplies chir to the gasification furnace, and a dust supply line that supplies the dust collected by the second collector to the combustion furnace. The ash is formed to be introduced into the gasification furnace through a communication path, and includes a line that extracts ash produced in the gasification furnace independently of the communication path and leads it to the combustion furnace. coal gasification equipment.