DE710724C - Process for producing a hydrocarbon-poor hydrocarbon gas in alternating operation - Google Patents

Description

Process for the production of a hydrocarbon gas with a low hydrocarbon content alternating operation The invention relates to a method for producing a low-hydrocarbon Hydrogen gas in alternation with alternating up and down gases, at where the * fuel is degassed in the upper part of the gas generator and in: Lower part is gassed. In such processes, strike out during the downward gassing the shock gases pass through the fire zone of the gasification room and thus become water gas decomposed, whereby the hydrocarbons and tar vapors are split up with it water gas that is as free as possible of these components is obtained, such as, for example for chemical synthesis is desired.

With such methods it has sometimes been shown that the height the fire or glowing zone is relatively small, which is an imperfect decomposition which results in smoldering gases. According to the invention, this deficiency is overcome by that during the downward gassing approximately at the transition point between degassing and Gasification zone an oxygen-containing gas, in particular air or oxygen-enriched Air or pure oxygen, üi the gas generator is introduced. Through this gas introduction the fuel in the upper part of the gasification zone is heated to a high temperature and becomes glowing brought so that the fire zone is considerably extended upwards. The smoldering gases thus sweep through a longer fire zone and are thus more completely decomposed, from which an extensive cleaning of the water gas from hydrocarbons and Tar products results.

When generating hydrocarbon gas in alternating operation, it is known Between the blowing and the first upward gassing, a brief period of air at the top Introduce the end of the fuel column and mix in the gas withdrawn below d - m water gas.

In the case of continuous procedures, in special cases, e.g. B. in a double fire generator, it has already been proposed to introduce air at the transition point between the degassing and gasification space. In these processes, however, the task is not to expand the glowing zone, especially in the case of -Mi, v ## ärtsgasen an exchange process, in order to effectively remove the gaseous hydrocarbons from the gas. Naturally, the inventive method can be used with particular advantage in the case of fuels which result in a relatively low fire zone, i.e. in the case of relatively inferior fuels with a high fire content, e.g. B. Brown Coals, Lignifehu. The described gas or air introduction is also particularly applicable to water gas generation processes in which the carbonization gases are circulated and thereby returned to the gas generator. The carbonization, - but can emphasize the downward gases, d ust, ie without Umwälzung- from the degassing zone into and through the gasification zone.

In the drawing is an example Ausführungsforni one for Implementation of the process is shown schematically in the plant.

The gas generator i has a gasifier shaft 2 and a smoldering # 3 above it. 4 is a re enerative superheater shaft z # and 5 a z. B. designed as a Dampfstralilgebläse circulation fan. The various shut-off devices built into the individual lines are indicated by 6. At the transition point between the gasification shaft 2 and the smoldering shaft 3 , wind nozzles 17, which are distributed over the circumference and are fed by a common ring line 18, open into the gas generator. The nozzles 17 open into an annular cavity, which is formed by the natural slope of the fuel between the narrower smoldering shaft 3 and the further carburetor shaft: 2, so that the air introduced through the nozzles acts on the fuel evenly distributed along the circumference of the gas generator. For the arrangement of such tuyeres, however, it is by no means a prerequisite that the gas generator has two special shafts 2 and 3 ; rather, such an arrangement is also possible in the case of a gas generator with a uniform shaft.

The gas generator i is filled with coal, which traverses the Schivelschacht 3 and then the gasifier shaft 2 downwards. The coal degassed and degassed in the smoldering shaft 3 arrives as coke in the gasification shaft 2, in the annealing zone of which it is gasified to water gas.

When hot blowing the generator, air is introduced in the direction of arrow 7 via line 8 into the gasifier shaft 2, and the blow gases formed flow through line 9 into superheater 4, where they are replaced by the addition of secondary air via line 1 6 in the Superheater is run, burned and heat the superheater to a high temperature. The burnt exhaust gases escape in the direction i o. When gassing upwards, a circulating current is generated by the fan 5 , which flows in the direction of the arrows X via the line i i, the # L, 711 part of the superheater4, lineg, distributor "g -" schacht2, Schivelschaclit3 and the Leitwi # -, I2 leads. ## Water vapor is fed through the line to the steam jet fan5 and thus to the circulated gas. This steam causes the formation of water gas when it passes through the hot-blown coke layer of the gasification shaft S 2. The mixture of carbonization gases and water, gas rising to the upper end of the smoldering shaft 3, is circulated in the above-mentioned circulating flow, where it is heated in the superheater 4 and finally passes through the fire zone of the gas generator i, where the column water tunnels and Tar mist takes place. Since constantly water gas is produced continuously arises a surplus gas, the i from the gasifier shaft 2 through the pipe 1 and the pipe 3, is eleitet ab. Since the water gas is diverted at a point at which the circulating flow has already passed the fire zone of the gasifier shaft 2, a water gas freed from hydrocarbons and tar vapors is obtained.

With the downward gases that now follow, the gas is circulated by setting the shut-off devices accordingly via line ii, the upper part of the over-ZD heat-s 4, line 9, smoldering shaft 3 and Lei-ZD device 12, so that here too the gas mixture removed from the smoldering duct 3 is heated in the superheater 4, heat is conveyed into the smoldering duct 3 and the gas in this is effectively de-humidified. The excess gas is when entering from the, branched line 9 in the gasifier shaft 2 ab strokes in the latter down and leaves the system through the nozzle 1 5 and the line 14. This branched gas part thus strikes in this period just before leaving the system through the glow zone of the gasifier shaft, where on the one hand the introduced water vapor and on the other hand also the carbonization gases are decomposed into water gas.

During the downward gassing, the tuyeres 17 are turned on , which causes the fuel in the upper part of the gasifier shaft 2 to glow and thus the glow zone above the grate is considerably lengthened upwards. The obtained from the described Kreisstromabgeziveigte gas portion which is fed through the carburettor shaft 2 downward and through the pipe 1 5 and the line 14 to the outside, sweeps soinit on a longer path through the annealing zone, whereby the decomposition of the Schwelga se, in a more perfect way will. Another advantage is that; the hot combustion gases, which result from the combustion caused by the air supply in the upper part of the gasifier shaft 2, are partly sucked downwards into the smoldering shaft 3 by way of the described circulating flow, whereby heat is supplied to the latter, the desulfurization is more intensive and thus the throughput of the generator is enlarged. Furthermore, there is the advantage that when gassing down, the carbonization gases also sweep through the fuel layer by way of the circulating current described, which was highly heated by the blowing in of air when gassing down, so that even when gassing up. any residues of tar and heavy hydrocarbons must be removed.

Claims (1)

PA-rLNTANSPRUCII: A process for preparing eineskohlenwasserstoffarrnen hydrocarbon gas in alternating operation with alternating up-and-down gases, characterized in that wärtsgasens down during approximately at the transition point between Ent-P U - a sauersungs-containing gas is introduced to the gas generator in and gasification zone..