JPS63186798A - Pressure coal charging method - Google Patents

Abstract

PURPOSE:To minimize the consumption of N2 gas and reduce coal running cost, by circulating N2 gas in a process for pressure charging of coal in which N2 gas is used as a pressure gas medium. CONSTITUTION:Adsorption apparatuses 18 and 19 are each operated by periodically repeating adsorption and desorption (regeneration) steps. In the adsorption apparatuses, the steps are operated in shift. That is, when one of the apparatuses is in the adsorption step, the other is in the desorption step. Each of lines 65, 67, 70, 66, 68 and 71 connected to both of the adsorption apparatuses is provided with a change-over valve. The air fed through line 64 is introduced into the adsorption apparatus 18, where the O2 gas in the air is adsorbed. The N2 gas not adsorbed there is returned to an N2 gas tank 15 through line 67. On the other hand, the adsorption apparatus 19 is evacuated by means of a vacuum pump 20, thereby causing the O2 gas adsorbed on an adsorbent to be desorbed. The O2 gas is discharged through line 74. Thus, the adsorbent is regenerated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for supplying coal to a coal gasification plant.

[Prior Art] In coal gasification plants, lime gasifiers are operated under pressure to increase efficiency. Therefore, it is necessary to pressurize the coal before supplying it to the gasifier, and a lock hopper type coal supply device is usually used in the dry type.

An embodiment of this conventional dry lock hopper coal supply method is shown in the flowchart of FIG. The main components of the feeding device include a normal pressure coal hopper 5, a pressurized coal hopper 6, a pressurized coal hopper 7 for metering, and a coal distributor 8.

Coal pulverized by the crusher 2 from the coal hopper 1 via the coal supply pipe 40 is sent from the hot blast furnace 3 via the combustion gas supply pipe 43 (by hot air, it is sent to the cyclone 4 via the pipe 44. 41 and 42 are supply pipes for air and fuel supplied to the hot air stove 5.

Coal is separated in cyclone 4 and transferred to rotary feeder 3
During this period, the hot air, which is sent to the atmospheric pressure hopper 5 and used as a transport medium, dries the coal and is discharged from the system through a pipe 45.

Coal is sent from the normal pressure hopper 5 to the pressurized hopper 6 via a rotary feeder 31 and pulp 32.

The pressurized hopper 6 is supplied with a pressurized medium gas (usually N! gas) sent via a pipe 54 in order to transfer the coal from the hopper 6 to the metering hopper 7 . The pressurized medium gas, ie N, gas is N! From the storage tank 11 through the pump 12 to the piping 52° to the evaporator 15. Piping55. pulp 5
5 and reaches a pipe 54. After the pressure hopper 6 is pressurized with nitrogen gas, the lime in the hopper 6 opens the pulp 53 and is transferred to the weighing hopper 7 via the pipe 47. After the coal is transferred to the weighing hopper 7, the pressurized hopper 6 receives lime from the normal pressure hopper 5, so it is necessary to return it to normal pressure. It is discharged via piping 56.

The weighing hopper 7 is also pressurized by nitrogen and gas supplied via the branch pipe 55 of the pipe 53 and the pulp 36. The metering hopper 7 is always operated under pressure during operation, but when stopped, the pressurized medium gas is supplied to the valve 38. It is discharged via conduit 57.

The coal in the weighing hopper 7 is pulp 34. The coal is transferred to the coal distributor 8 via the pipe 48 and supplied to the gasifier 9 via the pipe 51 with pressurized air.

The pressurized air is supplied from the pipe 49 to the coal distributor 8 via the pipe 50 after being pressurized by the air compressor 10 .

Gasifying agent is supplied to the gasifier 9 through a pipe 59 so as to form a fluidized bed 92 on a dispersion plate 91, and gasified gas is taken out of the system through a pipe 60.

In addition, conduits 56.5 are connected to the pressure hopper 6 and the weighing hopper 7, respectively.
The pressurized medium gas discharged through 7 is combined in a conduit 58, passes through a cyclone 4, and is discharged out of the system from a pipe 45.

[Problem that the invention seeks to solve]

As mentioned above, coal has the possibility of spontaneous combustion or ignition during handling such as storage and transportation, and an inert gas such as nitrogen is used as the pressurized medium gas. Generally, nitrogen is supplied to a pressurizing hopper and a weighing hopper via a liquid nitrogen tank and a conduit, and the inert gas filled in the pressurizing hopper is discharged and disposed of when the pressure is reduced, resulting in high running costs.

[Purpose of the invention]

The present invention aims to provide a pressurized coal supply method that can overcome the disadvantage of high running costs in the conventional pressurized coal supply method.

[Means for solving problems]

The present invention provides a method for supplying lime using a lock hopper type in a pressurized system consisting of an ordinary pressure hopper, a pressurized hopper, a weighing hopper, and a lime distributor. A gas tank is installed, and the pressurized hopper and weighing hopper are pressurized from the tank!
A pressure cycle type gas adsorption device that supplies gas and collects N2 gas discharged from the pressure hopper and the metering hopper into the N gas tank, and further fills the N gas tank with an 02 adsorption fW agent. and connect it to the N
, 02 gas mixed in N in the gas tank, gas is supplied to the pressure cycle type gas adsorption device together with air outside the system, 02 gas is removed and N2 gas is obtained, 0, N without gas?
This is a pressurized coal supply method characterized by returning gas to the N2 gas tank.

That is, the present invention has the following features: (1) The pressurized Nt Ganu discharged from the pressurized hopper and the weighing hopper is reduced to N! The N3 gas in the tank is supplied to a pressure cycle gas adsorption device filled with a 0-part adsorption type adsorbent to remove oxygen from the gas and returned to the tank f2) Hz gas tank) via a compressor Supplying N2 gas as a pressurizing medium to the pressurizing hopper and weighing hopper (3) A part of the N and gas used as the pressurizing medium cannot be recovered, so to replenish it, air is supplied from outside the system to the N gas tank. The N gas is combined with the gas supplied from the N gas tank and supplied to the pressure cycle gas adsorption device through piping, and the resulting N gas is collected in the N gas tank.

The points are new.

EXAMPLE Hereinafter, an example of the present invention will be explained with reference to the flow shown in FIG. In FIG. 1, the same reference numerals as in FIG. 2 indicate the same parts as in FIG.

Raw coal Hora 212 coal crusher 2. Hot stove 3. cyclone 4
．． Normal pressure hopper5. The construction and operation of the pressurizing hopper 6, the weighing hopper 7, the coal distributor 8, and the gasification kettle 9 are the same as those of the apparatus described in FIG.

In the flow of FIG. 1, the difference from FIG. 2 is that the piping 56 of the pressurizing hopper 6. It is enough that the pipe W57 of the weighing hopper 7 is connected to the pipe 58, and the V pipe W56. be. The cyclone 14 provided between the pipes 61 and 62 allows N! to flow through the pipes. Since the gas contains a small amount of pulverized coal, this is provided to prevent this from entering the N3 gas tank 15 and the subsequent gas adsorption device.

This N2 gas tank 15 is connected to the pressurizing hopper 6 and the weighing hopper 7 via the compressor 21 and the piping 55, and through the piping 54 and 55, respectively, as described in FIG. 2 via the piping 75.

As mentioned above, since 02 is mixed into the circulating N and gas, the O! In order to remove the gas, the additional KN1 gas tank 15 is filled with a pressure cycle gas adsorption device 1B, 1? and piping 6
3. Gas blower 16° is connected to piping 64, 65.66 and piping 67.68° 69.

The adsorption devices 18 and 19 carry out the adsorption process and desorption process (
The system is operated by periodically repeating the regeneration process. In addition, the adsorption equipment is operated with different processes, with one being in the adsorption process and the other in the desorption process. 65, 67 connected to both adsorption devices.
Switching pulps (not shown) are provided at 70, 66°, 68, and 71, respectively. The air supplied through the pipe 64 enters the adsorption device 18, and the 02 gas in the air is adsorbed.
The unadsorbed N8 gas is returned to the N gas tank 15 via the pipe 67, while the adsorption device 19 is evacuated using the vacuum pump 20, and the O gas adsorbed to the adsorbent is desorbed and discharged via the pipe 74. The adsorbent is regenerated.

In addition, air supply pipe 7 is used to supply inert gas (N1 gas).
2 is connected to the pipe 64 via the air blower 17 and the pipe 73, and is supplied to the adsorption device 18, 19.

In the flow shown in FIG. 1, the N2 gas discharged from the pressure hopper 6 or the weighing hopper 7 is
The gas in the tank 15 is supplied to the pressure cycle gas adsorption devices 18 and 19 to remove oxygen from the gas, and then returned to the tank 15.

Further, N2 gas is supplied as a pressurized medium from the N gas tank 15 to the pressurized coal hopper 6 and the metering hopper 7 via the compressor 21.

A part of the nitrogen and gas used as the pressurized medium cannot be recovered, so in order to replenish this, air is mixed with the gas supplied from the inert gas tank 15 through the conduit 72, and the pressure cycle gas adsorption device is connected through the conduit 64. The N8 gas obtained by supplying to the N gas tank 18 and 19 is collected through the conduit 69 and into the N gas tank 15.

〔Effect of the invention〕

Since N gas is used as the pressurized gas medium and the N gas is recycled, the consumption amount can be reduced and the fusing cost can be reduced.

The pressure cycle gas adsorption device @ allows υN to maintain oxygen in the gas below the required ftK degree.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing an embodiment of the present invention, and FIG. 2 is a flowchart showing an embodiment of a conventional pressurized coal supply method.

Claims (1)

[Claims] In a method of supplying coal by a lock hopper type in a pressurized system consisting of a normal pressure hopper, a pressurized hopper, a weighing hopper, and a coal distributor, an N_2 gas tank is provided and pressure is applied from the N_2 tank to the pressurizing hopper and the weighing hopper. A pressure cycle type gas adsorption system that supplies N_2 gas under pressure, collects the N_2 gas discharged from the pressurizing hopper and the metering hopper into the N_2 gas tank, and further fills the N_2 gas tank with an O_2 adsorption type adsorbent. connect it to the device,
The N_2 gas mixed with the O_2 gas in the N_2 gas tank is supplied to the pressure cycle type gas adsorption device together with the air outside the system to remove the O_2 gas and obtain the N_2 gas.
1. A pressurized coal supply method characterized by returning N_2 gas that does not contain 2 gas to the N_2 gas tank.