KR20150023221A - Method for operating a bulk material lock means - Google Patents

Abstract

There is provided a method for operating a system of bulk material locks used to charge a tank or reactor under positive pressure wherein the gas and partially the pressure energy during the decompression of the lock is adjusted by pressure compensation by one or more pressure tanks, It is reused during pressurization.

Description

[0001] METHOD FOR OPERATING A BULK MATERIAL LOCK MEANS [0002]

The present invention relates to a method for operating a system of bulk material locks, each of which is used to fill a processing apparatus comprising a process gas, such as a tank or reactor under positive pressure, Prior to this, the lock is depressurized to atmospheric pressure, escaping gas is collected in one or more tanks and stored for further use, and prior to draining the bulk material contents into the tank or reactor, And is pressurized by operating pressure.

This system of bulk material locks is formed by the locks of a plant that includes a plurality of substantially identical processing devices.

Methods for actuating bulk material locks that serve to charge the processing device under positive pressure are known. A very well-known example for this method is the charging of the blast furnace in the iron industry. When the lock is depressurized, the gas is collected, dedusted, and stored in a gasometer from which it is generally supplied as a fuel gas to its use. To pressurize the lock again, the progester gas is withdrawn directly from the furnace or after destroying. Here, because the blast furnace process produces a sufficient amount of blast furnace gas to enable the branching of the gas required to pressurize the bulk material without disturbing the blast furnace process, the collected gas It is not required to reuse itself [Ullmann's Encyclopedia of Industrial Chemistry, 6th ed., Vol. 18, pp. 2.5].

It is not so favorable in coal gasifier installations, as described in Ullmann's Encyclopedia of Industrial Chemistry, 6th edition, volume 15, gas production, chapter 4.4. A typical example of this technique is disclosed in German Patent Publication DE 10 2007 017 402 A1.

These gasifier devices, also referred to as pressure gasifier devices, are of the shaft-like type. In these gasification apparatuses, solid fuels such as peat, lignite, hard coal, coke, biomass and the like are produced from combustible product gas whose basic components are carbon monoxide and hydrogen . The axial pressure gasifier is charged with the fuel from above. In the shaft, the fuel forms a fixed bed that traverses in the opposite direction by a gas mixture consisting essentially of oxygen or air and steam. The product gas whose temperature is generally 800 ° C. or higher is withdrawn to the upper region of the pressure gasifier and is also supplied to the purification and subsequent use. The ash from the fuel is discharged from the bottom pressure gasifier, for example through a rotating grate. The pressure gasification process is typically carried out at a pressure of 15 to 50 bar. This appears to require filling the fuel in the shaft via a bulk material lock. In order to handle bulk material or fuel, the lock is pressurized to the process pressure by the product gas present on the axis of the pressure gasifier and is also depressurized to atmospheric pressure to take up the new charge.

In addition to the iron furnace furnace, the gas provides product gas during pressure gasification. In at least a large installation that constitutes several gasification apparatuses, it is therefore necessary to collect the gas released from the lock during decompression, to compress it again by the compressor unit to the operating pressure of the gasification process, .

However, it is not feasible for economical reasons to carry out the pressurization of the lock by means of the compressor unit, because the very large amount of gas each required for a tight notice is too large and also requires a costly compressor. In order to press the lock, the gas must therefore branch off from the gasification process, where it must be accepted that a uniform course of the gasification process is hampered by the removal of each of the gases to pressurize the lock.

Accordingly, there is a need for a method for operating a system of bulk material locks that avoids the disadvantages of the prior art that pressurization of the gas that has to be fed back into the production process after compression is less hindered and that pressurization of the gas must be less from the production process The purpose is to provide.

This object is solved by a method having the features of claim 1.

The contemplation of the present invention is that not only the gas but also some of the pressure energy present in the gas is stored in one or more pressure tanks since each of the locks is constituted by depressurizing the pressure tank into partial pressure stages by means of pressure compensation.

The smaller the distance between the starting pressure of the lock and the starting pressure of the pressure tank before pressure compensation, and also the smaller the pressure tank, the more pressure energy can be stored.

How many locks can be combined in such a system consisting of several locks and one or more pressure tanks depends primarily on the cycle and frequency of the lock cycle and on the number and cycle of pressure compensation steps.

Wherein the lock cycle is perceived as a depressurization of the lock to atmospheric pressure, charging the lock with the solid, pressurizing the lock with the operating pressure of the reactor, and also discharging the solids from the lock into the reactor.

The method according to the invention can be advantageously designed according to claims 2 to 5.

An advantageous aspect of the invention is that the first depressurizing step of the lock, carried out before the executed step, carried out in accordance with claim 1, is effected by pressure compensation with another lock of the system, d. < / RTI > In this way, much greater amounts of gas and pressure energy are conserved and less gas must be withdrawn from the gasification process for the lock to be compressed, so as to achieve the required operating pressure at the lock to handle the solids in the reactor .

Another preferred embodiment of the invention consists in that a final step for pressurizing the lock to the operating pressure of the connected device is carried out and pressure compensation is carried out between the lock and the device. For many applications, this step is problematic because direct gas retraction from the device can be very hot and can also contain constituent material deposited in the lock and can also lead to failure. In this case, the gas demand for this last pressurization step is too low, but it may also be carried out at high gas temperatures and at any concentration of the gas's condensable constituent material without compromising the operability of the lock.

A further preferred aspect of the invention is that a further depressurization step occurs after depressurization step (a) and step (b) according to claim 1, wherein a pressure compensation between the pressure tank acting as a containment tank for the compressor unit and the lock is carried out, , The gas being supplied into the product stream of the equipment supplied by the lock system. In this way, the process gas recirculated from the process through the lock is recirculated, and the yield of the process is also increased.

A further preferred aspect of the invention consists in that after the depressurization is carried out into the receiving tank of the compression unit, an additional depressurization to near atmospheric pressure is effected by means of the pressure compensation to the gas tautomer. In this way, the maximum possible amount of gas can be collected and stored. Due to storage, the gas can be supplied for further use, for example as a fuel gas.

As an alternative to storage in the gas torch, this may be economical compared to the removal of the gas through a torch.

Particularly advantageously, the present invention can be used to implement a method for pressure gasification of solid fuel. Because these methods operate at pressures above atmospheric pressure, the addition into the pressure gasification device must be performed through a lock to minimize the gasification process as little as possible. While the product gas required exclusively for the pressurization of the lock is withdrawn from the pressure gasification process in accordance with the prior art, the present invention is advantageous in an economical way, that is to say, partially with the gas drained from the lock during decompression, Lt; / RTI > In this way, less gas must be withdrawn from the pressure gasifier for pressurization and the process is less disturbed.

The present invention also encompasses an apparatus for operating a method according to any one of claims 1 to 5, including at least one system of bulk material locks each operative to charge a processing apparatus under positive pressure, the system comprising at least one An additional pressure tank, a pressure gauge, and a torch conduit having a pressure tank and an optionally connected gas compression unit, wherein the lock, tank, and torch conduit are arranged such that all parts are capable of performing gas exchange with all other components, Lt; / RTI > Advantageously, the components are connected to a header conduit. In larger systems, it may be desirable to use several head conduits, one for each of the pressure tank (s), gas compression unit, plasticizer, and / or torch conduit, for example.

Exemplary Embodiment

Further developments, advantages, and possible applications of the invention can be obtained from the following description of illustrative embodiments and drawings. All of the features described and / or illustrated form the invention, either by itself or in any combination, independent of those contained in the claims or the background documents thereof.

Figure 1 shows a partial view of a system of bulk material locks according to the invention, for example with two pressure tanks and a potentiometer.
Figure 2 shows a partial view of a system of bulk material locks according to the invention, for example with two pressure tanks, a potentiometer, and a compressor unit in which a gas receiving tank and a compressor are shown.

In the following example, the mode of operation of the method according to the present invention will be described with reference to two exemplary embodiments.

Example 1

Bulk material supplied to the lock or discharged from the lock into the reactor is shown as a flow arrow or conduit (4,5,6,7). The bulk material locks (A, B) have a volume of 12.1 m 3, respectively, like the pressure tanks (C, D). The potentiometer E serves to store the reduced pressure gas at approximately atmospheric pressure. The blower F serves to transport the gas for its further use through the conduit 7, for example as a fuel gas or for its removal via a torch. The locks, pressure tanks, and potentiometers are connected to each other to exchange gas through conduits 8, 9, 10, 11 and header conduit 3. The conduits 1,2 perform pressure compensation of the locks in respective tanks or reactors (not shown) to be charged.

Startup situation

- Lock (A) is filled with 54% by volume of solids and 46% by volume of gas. This will be at atmospheric pressure and subsequently be pressurized to an operating pressure of 50 bar (g) of the tank or reactor (not shown) supplied by the lock to drain the solid contents into the same portion.

- The lock B which drains its solid contents supplied by the same part into the reactor (not shown) is at this operating pressure of 50 bar g and is again depressurized to atmospheric pressure to be filled with solids will be.

- The pressure tank (C) is at a pressure of 29.5 bar (g).

- The pressure tank (D) is at a pressure of 38.8 bar (g).

- The potentiometer (E) has a constant nominal atmospheric operating pressure.

Method Step 1

20.2 Pressure compensation between lock (A) and pressure tank (C) in bar (g).

Method Step 2

Pressure compensation between lock (A) and pressure tank (D) at 32.9 bar (g).

Method Step 3

Pressure compensation between lock (A) and lock (B) at 44.6 bar (g).

Method Step 4

Pressure compensation between lock (A) and the reactor at 50 bar (g).

Method Step 5

Pressure compensation between lock (B) and pressure tank (D) at 38.8 bar (g).

Method Step 6

Pressure compensation between lock (B) and pressure tank (C) at 29.5 bar (g).

Method Step 7

Pressure compensation between the lock (B) and the plasticizer (E) at nearly atmospheric pressure.

Due to the procedure described in this example, 40 vol.% Of the gas released from the lock can be reused to depress the lock to depressurize the same portion. The remaining 60 vol.% Of the gas of the reduced pressure gas is discharged into the potentiometer and is also removed therefrom through the torch and / or fed to be reused as fuel gas. In the prior art, 100 vol% of the reduced pressure gas has to be treated in this way. The compression of this gas, which is depressurized to the atmospheric pressure to the extent that it can be used to press the lock, or it can be mixed with the product gas at the outlet of the gasification reactor, is not an economical recipe.

Example 2

Bulk material supplied to the lock or discharged from the lock into the reactor is shown as a flow arrow or conduit 4 ', 5', 6 ', 7'. The bulk material locks A 'and B' have a volume of 12.1 m 3, respectively, like the pressure tanks C 'and D'. The potentiometer E 'serves to store the reduced pressure gas at approximately atmospheric pressure. The intake F 'serves to transport the gas for its further use through the conduit 7', for example as a fuel gas or for its removal via a torch. The locks, pressure tanks, and plasticizers are connected to each other to exchange gas through conduits 8 ', 9', 10 ', 11' and header conduit 3 '. The conduits 1 ', 2' perform pressure compensation of the locks with respective tanks or reactors (not shown) to be filled.

Further, the system includes a compression unit and a compressor (H) indicated by a gas storage tank (G) having a volume of 300 m3. The gas pressure of the gas storage tank G is maintained at 3 to 4 bar (g). The compressor H compresses the gas to a product gas pressure present at the outlet of the gasification reactor (not shown). Through the conduit 13, the tank G is filled with the reduced pressure gas from the lock. Through the conduit 14, the compressed gas is mixed with the product gas leaving the gasification reactor.

Startup situation

- Lock (A ') is filled with 54% by volume of solids and 46% by volume of gas. This will be at atmospheric pressure and subsequently be pressurized to an operating pressure of 50 bar (g) of the tank or reactor (not shown) supplied by the lock to drain the solid contents into the same portion.

The lock B 'which drains its solid contents into a reactor (not shown) supplied by the same part is at an operating pressure of this reactor of 50 bar g and is also depressurized to atmospheric pressure to be filled with solids again will be.

The pressure tank (C ') is at a pressure of 29.5 bar (g).

- The pressure tank (D ') is at a pressure of 38.8 bar (g).

- The potentiometer (E ') is at nominal atmospheric pressure.

- The gas storage tank (G) is at a pressure of 3 bar (g).

Method Step 1

20.2 Pressure compensation between lock (A ') and pressure tank (C') with bar (g).

Method Step 2

Pressure compensation between lock (A ') and pressure tank (D') at 32.9 bar (g).

Method Step 3

Pressure compensation between lock (A ') and lock (B') at 44.6 bar (g).

Method Step 4

Pressure compensation between lock (B ') and reactor at 50 bar (g).

Method Step 5

Pressure compensation between lock (B ') and pressure tank (D') at 38.8 bar (g).

Method Step 6

Pressure compensation between lock (B ') and pressure tank (C') at 29.5 bar (g).

Method Step 7

Pressure compensation between lock (B ') and gas storage tank (g) with 4 bar (g).

Method Step 8

Pressure compensation between lock (B ') and plasticizer (E') at nearly atmospheric pressure.

Due to the procedure described in this example, 40 vol% of the gas released from the lock for its depressurization can be reused to pressurize the lock. The other 50 vol% are compressed by the compression unit to such an extent that they can be mixed into the product gas stream of the gasification reactor. Only the remaining 10 vol.% Should be released into the ketometer or removed therefrom or supplied in a further subordinate use, for example as a fuel gas.

A, B, A ', B': bulk material lock
4, 5, 4 ', 5': Addition of bulk material (conduit)
6, 7, 6 ', 7': Release of bulk material (conduit)
1, 2, 7, 8, 9, 10, 11, 12, 13, 1 ', 2', 7 ', 8', 9 ', 10', 11 ', 12', 13 ' conduit
3, 3 ': header conduits C, D, C', D ': pressure tanks
E, E ': plasticizer F, F': intake
G: Gas storage tank H: Compressor
Bar (g): Bar of positive pressure

Claims (7)

CLAIMS 1. A method for operating a system of bulk material locks, each of which is used to charge a processing apparatus comprising a process gas under positive pressure, wherein before filling with the bulk material, the lock is depressurized to atmospheric pressure and the escaping gas is introduced into a pressure tank The method of decompressing and pressurizing the lock, which is collected in one or more tanks, such as a meter, and stored for further use, before the bulk material contents are drained into the apparatus,
a step of depressurizing the lock by pressure compensation by a pressure tank including a process gas, the starting pressure of which is below the starting pressure of the lock;
b) an initial pressure of one or more additional pressure tanks, each of which is below the pressure tank used in step (a) or the pressure of a previously used pressure tank, Optionally one or more additional depressurization steps by compensation;
c) an optional pressurization step by pressure compensation by the pressure tank listed below step (b), which starts the tank at the lowest pressure and continues with each tank at the next higher pressure;
d) a step of pressurizing by pressure compensation by the pressure tank listed in step (a) below. The method according to claim 1,
Characterized in that before depressurizing step (a) of claim 1, the depressurization step is carried out by pressure compensation by another lock of the system and is first pre-pressurized by steps (c, d) according to claim 1 Method of operating the system of the material lock. 10. A method according to any one of the preceding claims,
Characterized in that the final pressing step for adjusting the lock pressure to the height of the operating pressure of the connected device is effected by pressure compensation between the lock and the device. 10. A method according to any one of the preceding claims,
Characterized in that, when the lock is depressurized, an additional depressurization step is carried out by pressure compensation of the lock by means of a pressure tank acting as a receiving tank for the pressure unit after carrying out steps (a) and (b) How the lock's system works. 10. A method according to any one of the preceding claims,
Characterized in that the pressure is reduced by the pressure compensation by the pressure gauge after the step (a, b) of claim 1 is carried out and the pressure tank is depressurized according to claim 4 when the lock is depressurized. How the system works. The use of a method according to the preceding clauses for carrying out the method for the pressurized gas of solid fuel:
Characterized in that the at least one bulk material lock acts as an axial type pressure gasifier. An apparatus for operating a method according to any one of claims 1 to 5, comprising a system of bulk material locks, one of which acts to charge a processing apparatus under a positive pressure,
The system includes an additional pressure tank, a plasticizer, and a torch conduit having at least one pressure tank and an optionally connected gas compression unit,
Wherein the lock, the tank, and the torch conduit are connected through a pipe conduit such that all parts can be subjected to gas exchange with all other components.

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