DE1571710C3 - Process for producing low-smoke fuel briquettes - Google Patents

Description

Briquettes required substances. On the other hand, too low a temperature leads to too long a degassing time, during which the binder component partially loses its cementing property before deformation. The degassing time according to the invention is also restricted even more by the fact that the device in which the briquetting material must be moved during the degassing process - e.g. B. a stirred tank or a screw - _: 'in practice has a limited capacity. The degassing time should therefore be at least 1 minute but not more than 15 minutes. According to the invention, a minimum temperature of 450 ⁰ C, but not above. 530 ⁰ C lying temperature come into use. Time and temperature are related to each other according to law.

A particularly advantageous working area for the method according to the invention is in the area and above the resolidification temperature, like.sie in DIN 51 739 in the version of March 1956, which relates to the dilatometer test.

All hard coals can be used as the binding agent component, if necessary with a very high Soften the heating rate under the conditions of this procedure.

According to a further embodiment of the method according to the invention, the degassing takes place without External heat supply when the temperature of the briquette remains roughly the same or slightly lower. In the context of the method according to the invention, a method for determining referring to the original tar yield. With the help of this determination method, in analogy to a Embodiment the for a certain briquetting very tight boundary conditions of the thermal Pretreatment can be determined. The operator of a hot briquetting plant in which the composition of the briquetted goods normally only changes at long intervals, also has to do with the

ίο Determination of the residual volatiles and the relation between residual volatiles and original tea spoil a simple one Means of operational control.

The method according to the invention is referred to by the following exemplary embodiments would take on the drawings explained. It shows :

F i g. 1 is a schematic representation of an exemplary arrangement for implementing the inventive Procedure,;

2 shows a curve representation of the reduction the tar yield as a function of the degassing time at different degassing temperatures and

F i g. 3 is a graph showing the reduction the original tar yield and volatile components of the briquetting material.

For example, the following starting materials are used to produce the low-smoke fuel briquettes in the proportions indicated below and with the volatile contents indicated Ingredients and used on Urteer:

component
0 /
/ ο portion Content of
fleeting
Components Proportionate
Content of
volatile ■
Components Primal tar
yield Coke breeze 10
30th
35
■ 25
100 0.5
9.0
15.0
32.0 0.05
2.70
5.60
8.00.
16.35 0.0 anthracite 2.1
10.1 Charcoal Gas coal

Anthracite and coke breeze are pre-mixed and treated as a single component (inert component I). -

The edible coal E is converted into a semi-coke with 10% volatile components (inert component II) by carbonization in a fluidized bed. The smoldering temperature is about 550 ° C, the smoldering time about 15 minutes.

In principle, the starting materials are heated as described in the first paragraph of the description. In the heating pipe α ^{, component I is brought to about 600 °} C. by direct contact with fire gases and via a cyclone b. eliminated. In the b emerging from the cyclone exhaust gas G coal is added and heated in a tube at about 25O ⁰ C. The binder component is separated out in a cyclone d. The dust that passes through is captured in a downstream electrostatic precipitator e and fed to the gas coal. The edible coal E fed to the fluidized bed is pre-degassed here and with its fine grain fraction, which is captured in a cyclone g , it forms the inert component II; it is introduced into the screw conveyor A.

The three solid components mentioned are introduced into a container k , in which mixing and degassing according to the invention take place. A vertical cylinder with a diameter of 1 m and a jacket length of 4 m is used for a press output of 20 t / h. The lower end of the cylinder merges into a rectangular cross-section of 0.7-1 m. The container contains an agitator with a vertical axis. The container volume that can be used for the briquetting is not quite 3 m ³ . ^{A mixed temperature of 480 0} C results from the different temperatures of the individual components.

The degassing according to the invention, ie the mean residence time of the material to be briquetted in the container K, takes about 5 minutes in this example. In this container, the degassing takes place without external heat input, preferably when the temperature of the briquetting material remains approximately the same or has slightly decreased. Because the container k is not insulated, the temperature drops by about 12 ° C. during this time. The gas escaping during the degassing is a strong gas with an extraordinarily high tar yield. The ready-mixed and pre-degassed

5 6

Briquetted material is fed through a feeder of a roller trap to constant temperatures during the

press 1 abandoned. Specified for the given press gassing process. The abscissa is the

power, the dwell time of the briquetting material in the gassing time is plotted in minutes, as the ordinate

Container k determined by the level. the primary tar yield in percent. You can see that you are

The primary tar yield of the three components and the primary tar yield both by changing the

indirectly before mixing is: degassing temperature as well as through change

inert component 1 0 ° / ₀ can influence the degassing time at will.

inert component II '\'.'. . ". '.'. '.'. '.'. '.'. '.. 0% ^ln __ ^F ' ^l 8- \ ^is ?, ^ΑεΓ » ^Bere1 ^. ^The invention

Binder component 10% | ^{emaß m} J.. Creation of a smoke-free and stable

ίο Briquettes leads, hatched entered. He extends

The additive primary tar yield is 2.5% over a period of 1 to 15 minutes'

When leaving the container, the primary tar degassing time and a primary tar yield is the

yield. 0.5%. Since the mixture supplied to the press after the pressing process is between 0.2 and

the degassing continues for a short time, occurs up to 0.8% · that obtained in this exemplary embodiment

Once the briquette has cooled down, it produces a further reduction in the residual content of primordial tar immediately before deformation

tion of the primal tar yield, which is indicated in the present by a circle,

Example at around 0.2% Hegt. Finally, FIG. 3 shows the for the aforementioned briquetting

air oxidation occurring around the course of cooling and the area of degassing according to the invention

to a final lowering of the primary tar yield by a valid, almost linear dependency between primary tar

again about 0.2%, so that in this execution 20 yield and volatile constituents. At the same

example, the primary tar yield of the finished briquette, permanent starting material and constant mini-

is only about 0.1%. The determination of the

In Fig. 2 is for the mixture of these residual volatiles on the basis of samples that are immediately

example, the drop in the primary tar yield was taken from in front of the press and quickly - _:

their initial value of -2.5% with progressively 25 by immersion in water - cooled

tender degassing time for different, in this, as a simple means of operational control.

1 sheet of drawings

Claims (3)

1 2 State of the briquetting material at the time of the patent claims: formation, which is given by the extent of this degassing; determines the strength, the shape 1. Process for the production of compacts, resistance and the low smoke content of the produced especially fuel briquettes, by hot pressing 5 briquettes. The lack of smoke is also still in a fine-grained mixture from the further degassing of the small amount at press temperature softening coals, one under the shaped briquette and one under the softening point has a lying temperature, cooling by the oxygen in the air an oxidation which is hardly or not at all called at the pressing temperature. softening substance (inert substance), which is heated to such an extent at the temperatures customary up to now that the mixture tends to deform the briquettes produced without such degassing of the briquettes before subsequent pressing Mixture before it is used in the house fire to a compression of a degassing (for the purpose of removing cursed not inconsiderable smoke formation,
tiger constituents) is subjected, thereby 15 A method is also known, characterized in that a ^{duration between 1 and 15 minutes with a pre-degassing of 2 minutes at 490 0} C and a duration between after the actual heating process. The temperature is 450 and 53O ° C, and the temperature is removed. However, the specified values are ■ gassing matched to one another in such a way that a reduction is not sufficient for a reproducible process. the original tar yield of the briquetting material that can be briquetted using softening coal at the time of deformation to a binding agent component that is as firm and smoke-free as possible, with an amount of between 0.2 and 0.8 low-burning hot briquettes,
results. , The object of the present invention is to provide a 2. The method according to claim 1, characterized by precise teaching on the conditions of those who that when using softening coals as gassing to give the mixture before the Verals Binding agent component which is to be subjected to degassing during pressing. Range and above the temperature at re-For this purpose, it was found that the maximum original solidification of this binder component takes place. tar yield of the briquetting material at the time of 3. The method according to claim 1 and 2, characterized in deformation - d. H. in practice the tar yield, characterized in that the degassing without external 3 ° the one immediately before or immediately after the Heat input when the specimen is roughly the same or has been deformed and drawn and cooled quickly Slightly falling temperature of the briquetting - a measure of the condition of the briquetting he follows. good is. The determination of this primal tar yield ■ '' can e.g. B. according to the "known method of 35 Fischer (see Brückner, »Investigation Ver- “Driving for solid fuels” 1943). To the We recommend increasing the accuracy of the original tar determination for fuels with less than 0.4% original tar The invention relates to a method for producing it, the sample amount of 50 g, as after of pellets, especially fuel briquettes, by Fischer's method, to 1 kg, for example Hot pressing of a fine-grained mixture from at raise. With these fuels you bet Press temperature softening coal, the one; under ■ also expediently the end temperature of the temperature is below the softening point, swelling up to 550 to 600 ° C in order to achieve the maximum obtainable and at the same time with a primal tar yield which is hardly or not at all at the pressing temperature relevant substance, which is heated so high that the 45 reduce the time required for the determination. Mixing the required final temperatures for subsequent pressing .the carbonization of 500 to 600 ⁰ C. has borrowed temperature, the resulting lead in the fuels which can be used here in the Mixture before pressing a degassing, generally to comparable primary tar yields. It is thrown. . ·,. it should be noted in this context, In known processes, it is immediately rm 50 that the tar yields of natural hard coals are a Following the 'mixture represent the compression of the measure for the lack of smoke and the following Mixture made into briquettes. It has been shown to have approximate values: but in the production of low-smoke briquettes »;,.„ ■, _{Λ1 κ;} _ π το / . ,, -ο. · Ι ι ι ι η · ι · .. ι ·. 'rtninrazii υ, ι dis> υ, / I ₀ shown with softening coal as a binder. Lean coal 0 7 to I ⁰ / that without degassing the binder component 55 charcoal - 1 'to 4 ° / ° even at a temperature of the briquetting material ■ before carbonaceous 4 to 11 ° / ° the deformation of 450 ° C and more the briquettes _gas . _and gas flame coal ''. '. 11 to 14% after pressing to burst or to. are prone to undesirable cracking. This scha-. To solve the task at hand, the presumably based on the fact that in these 60 inventions to proceed in such a way that one between higher working temperatures also in the molded 1 and 15 minutes lying duration and one between Briquette, especially since the deformation has a temperature of 450 and 530 ° C for degassing increase occurs, the strong gas development continues to be coordinated so that a running. In order to reduce their scope, a reduction in the primary tar yield of the briquetting material must be reduced limited degassing of the mixture before the 65 at the time of deformation to between pressing are carried out, namely above the amount of 0.2 and 0.8%. Degassing addition, of the binder component. A temperature above 53O ° C leads to a is already subjected to the heating. The rapid destruction of the for the solidification of the