SE433616B - PROCEDURE TO USE HEATED IN COOK IN A COOKING PLANT - Google Patents

Description

7308045-4 40 Z devices, fans, injection coolers, heat exchangers and afterburning chambers for combustion of the water gas content from the extinguishing. The plant is therefore very expensive from a manufacturing and operational point of view.

DE-OS 24 34 827 discloses a process for energy recovery in gas production processes, such as coal gasification plants or coal coking plants, for the purpose of drying or preheating the starting materials, in particular fine coal for coke operation, the drying and preheating of the starting material with the aid of the starting material waste heat, which is recovered during the cooling of the residues from the process, for example by dry-quenching the coke in a coke plant in a closed, dust-separated primary gas cycle, using as inert transport and drying medium an inert gas such as nitrogen gas, coke flue gas - furnaces or flue gas from blast furnace combustion in a secondary gas cycle with dust separation. The necessity of two separate circuits for carrying out this method also entails expensive parts of equipment, such as heat exchangers, dust collectors and fans.

From GB-PS 1 334 373 it is known per se to use the sensible heat from hot coke in a coking process for drying and / or preheating coal, by passing an inert gas into circulation through the hot coke and coal, whereby the inert gas can be part of the combustion products of the fuel gases, which can also be used for coking. This also pre-treats both the heat carrier gas supplied for the coke cooling for inertization and the gas in circulation between coke cooling and preheating. The object of the present invention is to eliminate stated inconveniences according to the prior art in a process or a plant of the kind initially indicated and to achieve an economical utilization of the sensible heat from coke.

This object is solved according to the invention so that as heat carrier gas, blast furnace gas is used, which is led directly from the steel plant to the coke cooling plant. It is then appropriate that the blast furnace gas both in the coke cooling plant and in the coal preheating plant is directly brought into contact with the coke resp. coal.

In the present process, the flue gas of the coke oven battery to be used as the heat carrier gas is deliberately refrained from purifying, and the weak gas is formed during the cooling of the coke. m vw ”. m vn ...

H3 7808045-4 Since the flue gas leaving the regenerator or recuperator in a coke oven has both a significant water vapor content and a residual oxygen, the endothermic water gas reaction and the exothermic partial oxidation in the temperature range exceed 600 ° C during the dry coke cooling. Due to the predominance of the water gas reaction, the summation reaction is nevertheless strongly endothermic.

In addition to the hot flue gas incoming at 200-ZSOOC, the endotherm of this reaction also contributes to a large extent to the cooling of the coke. Water vapor and oxygen are thus not removed from the flue gas.

In the present process, the heat carrier gas is always brought into direct contact with the coke or the coal, both in the coke cooling plant and in the coal preheating plant. As a result of the reaction described, a dry gas is obtained from the flue gas during the dry coke cooling, which after the direct heating in the dry coke cooling is led to the coal preheating plant and where the coke cools in direct contact with them and preheats it to more than 100 ° C. In the alternative use of blast furnace gas as heat carrier gas, only a coupling of the two process steps "dry coke cooling" and "coal preheating" takes place.

Blast furnace gas, which is normally available in each steel plant, is passed as cooling gas through the dry coke cooling plant, heated there and then passed to the coal preheater. Here it again emits the heat in direct contact with the coke coil while simultaneously absorbing the water deducted from the coals.

The weak gas or combustion gas formed during the dry coke cooling can, if not to be used in another way, be at least partially supplied to a combustion chamber, in which it is combusted to an inert heat carrier gas for the coal preheating plant.

If the weak gas formed during the dry coke cooling is combusted and passed through the coal preheating as flue gas, a condensation of the absorbed water is superfluous.

After flowing through the coal preheating plant, the heat carrier gas can be extracted from the water taken up in a condensation step and / or dust in a fine dust cleaning step. 7 The condensate which precipitates during the condensation can be used for wet coke post-extinguishing. The fuel gas originating from the coal preheater and possibly purified combustion gas is in the coke oven battery itself, such as sub-combustion gas and / or for other carburizing gases for the sub-combustion gas and sub- and / or sub-combustion purposes.

The blast furnace gas purification or drying is automatically re-supplied from the coal preheating plant (the combustion gas (the blast furnace gas) can be obtained. A heat exchanger cooling,. . - - å required in this kind of use of m fl SUšHSša5 5 5 ° m heat carrier gas.

As long as it is burned during heating, it should be supplied under pressure, by oxygen in the system is certainly prevented.

The particular advantage of the present process is that the cooling gas, which is made available from the flue gas from the coke oven battery or as blast furnace gas, is passed both over glowing coke and through the coal preheating plant and more specifically not at the end but in an open circuit. Since the continuously formed flue gas and possibly also the blast furnace gas are constantly available and only once are passed through the various process steps, it is therefore not necessary to provide any compensation, which is necessary at the anlägg ü fi a plants operating with the greenhouse gas moving. if SVa§ga $ or so that an intrusion closed circuits, which necessarily show leakage.

A further special advantage of the present solution is that the weak gas formed from the flue gas from the coke oven battery and possibly the blast furnace gas with low water content in the coal preheating plant meet moist coal. Even during the combustion of the weak gas formed according to the invention, which enters the combustion chamber of the coal preheating plant at 500-800 ° C, an inert heat carrier gas with a much lower water content is formed than with combustion gases, such as coke oven gas, natural gas and the like. Accordingly, the concentration difference between moist coal and heat carrier gas is very high in all variants of the present process, in any case much higher than in known pneumatic carbon drying processes. These high concentration differences (concentration cases) are very favorable for the actual drying process. Accordingly, in the present process, the waste heat from solid residues from the coking process is again made useful indirectly by high-economy coal preheating. The released heat carrier gas is useful for the most different purposes of ignition and the like, after it has left the plant.

By using a heat carrier common to all process steps, fine dust separation after the dry coke cooling can be avoided. The number of necessary equipment parts is therefore reduced for the present plant in comparison with known plants.

The accompanying drawing illustrates the present method and associated plant in a block diagram. All the features shown therein form the present invention alone or in a fertilizingly meaningful combination. 7808045-4

Claims (8)

t a7sos04s-4, Claims A process for utilizing the perceptible heat in coke in a coking plant during dry coke cooling and coal preheating, wherein a heat carrier gas is successively passed through the coke cooling plant and the coal preheating plant, characterized in that as a heat carrier gas , which is led directly from the steelworks to the coke cooling plant. 2. A method according to claim 1, characterized in that the blast furnace gas both in the coke cooling plant and in the coal preheating plant is directly brought into contact with the coke and the coal, respectively. _ _ A method according to claim 1 or 2. characterized in that at least a part of the blast furnace gas coming from the coke cooling plant is fed to a combustion chamber, in which it is burned to an inert heat carrier gas for the coal preheating plant. 4. A method according to any one of claims 1-3, characterized in that the absorbed water is drawn off the blast furnace gas or the heat carrier gas in a condensation step and / or the dust in a fine dust purification step after the flow of the coal preheating plant 5. A process according to any one of claims 1-4, characterized in that the condensate precipitating in the condensation is used for wet coke quenching. A method according to any one of claims 1-5, characterized in - t e c k n a t thereof; that the possibly dried and purified blast furnace gas, which originates from the coal preheating plant, was used as a sub-ignition gas in the coke oven battery, as a carburizing gas for the sub-flue gas and / or for other carburization or under-burning purposes. 7. A method according to any one of claims 1-6, characterized in that blast furnace gas originating from the coal preheating plant is returned to the blast furnace gas line. 8. A method according to any one of claims 1-7, characterized in that the blast furnace gas is conducted under pressure.