SU48157A1 - Continuously operating coal burning shaft furnace - Google Patents

Description

In the existing mechanized coal burning furnaces of horizontal or slightly inclined type, drying and pereuglyvanie wood is done in trolleys, which creates the need for long tunnels e large surface heat transfer, with little use of useful volume and with a large expenditure of labor for maintenance.

To meet the needs of metallurgy in charcoal, it is necessary to build charcoal kilns that would have as their first task to produce top quality charcoal with the simultaneous use of all combined-cycle gas decomposition products and at the same time were maximally mechanized and produced daily charcoal.

Stafford's retorts in the Ford plant, the heatman of Professor Izhevsky, the heatman of Professor Sokolov, and the Gincha peat furnace, differing in their small size and low labor force, have significant productivity. Experiments prof. V.E. Groom-Grzhimailo in 1902

in Nizhnyaya Salda, but producing charcoal in a shaft furnace gave coal of excellent quality. The Goler's shaft kiln for heating the metal yielded better results compared to the horizontal kiln.

As applied to charring, shaft furnaces have not been fully developed, but modern theories and practices in furnace business give rise to the possibility of creating a coal-burning shaft-type furnace as the most rational one.

The main considerations adopted when creating such a uiaxTHOft furnace are the following:

1. Wood entering the kiln should not be taken in the form of ordinary firewood, but in the form of short-sawn round chocks with an average size: 200-300 mm in diameter and 200-300 mm in diameter; this makes it possible to get rid of wood chopping and all wood cutting is carried out on a saw installation that is 3-4 times more productive than the existing sawmill, and also makes it possible to speed up the wood drying process and improve the condition of wood loading into the kiln.

2. Get the highest yield of top quality metallurgical charcoal.

3. Use fully commercial products for drying and decomposing wood and, if possible, in a cleaner form.

4. Reduce fuel consumption for drying and charring wood to a minimum.

5. Have the ability to control the course of drying and charring of wood, as well as control the furnace.

6. To create a high-capacity furnace with full mechanization of the whole process,

7. Make the unit compact.

8. In order to reduce the consumption of metal, be freed from the trolleys.

In the attached drawing, the furnace of the proposed construction is shown in FIG. 1 in a longitudinal section and in FIG. 2 - in a section on a line, LV.

Wood in the form of chocks (200-300 mm long and an average diameter of 250 mm) from the warehouse is fed by a conveyor-drag line 1 to the bunker 2. From the bunker, the wood enters the lower part of the furnace 3, from which a lift, carried out in the form of two conveyors 4, is fed to the wood pre-drying zone 5.

Each elevator conveyor consists of eleven chains 6, equipped with teeth. For better supply of wood to the elevator, the teeth of the 7 are set at the bottom of the bunker, driven by the elevator motor, and below the pinwheel of the upper conveyor 8, a larger diameter is made. The speeds of the elevator conveyors are the same and are set depending on the performance of the furnace. The circumferential speeds of the gears 7 are greater than the speed of the conveyors, but have the same angular speed with the pinwheel 8.

The elevator and the gears are driven from one common motor 9 through the gearbox 10, allowing the speed of the conveyors and the gears to be varied by rotating the gearbox flywheel. In addition to this design of the lift, a second variant with the replacement of chains with screws can be proposed.

The wood pre-drying zone has a 60 ° slope to the horizon.

Wood, dried to a moisture content of 5-10%, from the pre-drying zone through the threshold 11 is transferred to the final drying zone 12.

A gate is installed above the threshold, separating the zones of preliminary and final drying of wood, with the aim of sharply separating the course in these zones. The need for a gate is finally established during operation of the furnace.

From the final drying zone 12, the wood flows by gravity through an inclined shaft (at an angle to the horizon of 45) enters the charring zone 14 and then into the coal cooling zone 15.

At the end of the cooling zone, a coal conveyor 16 is installed, receiving pressure of the coal and wood layer in the mine and evenly supplying coal to the coal bin 17. As the coal bunker is full, the gate 18 opens, and the coal is discharged into the trolleys, railway cars, onto the conveyor belt or another kind of transaort.

By unloading the coal, the furnace operation process ends. The preheated wood zone is heated by a mixture of gases produced in the furnaces of the drying zone and the heat exchanger and leaving the drying zone.

The furnace 19 of the drying zone is heated by waste fuel (debris from coal, sawdust, sliver, etc.), and also has a burner for burning non-condensing gas obtained from the decomposition of wood. The mixture of gases enters the pre-drying zone of wood through the window (channel) 20 with temperature, passes through the wood from top to bottom and exits through the windows 21 into the tube 22 of the exhauster 23 with the engine 24.

The gas mixture consists of gas from the heat exchanger furnace, which passed through the heat exchanger, from the gas that has passed the pre-drying zone and taken through channel 21 and dried in condenser 27,

and nz gas from a furnace arranged specifically for the drying zone.

Condensate water that forms with turpentine drains down, pre-drying zones of wood. The drainage is made through pipe 25, which allows the installation of a water seal. If the water gate is not needed, the water is drained through pipe 26.

From the exhauster, the gases go to the condenser 27, where the remaining water vapor and turpentine are condensed, and some of the gases are released outside. From the condenser the required amount of gas through the mixer enters the pre-drying channel of wood.

In this way, compulsory circulation of gases in the wood drying zone is established, which allows both the temperature of the gases and their quantity to be widely regulated. The direction of gases from top to bottom, i.e., according to their natural tendency, during cooling creates uniform flows of gases in the mine, and hence the uniform drying of wood. The separated vapors at the top of the mine will be in a superheated state and significantly speed up the drying of the wood, drying the wood throughout the whole mass, and not over the surface (as is usually the case in other kilns). Drying the wood will be uniform, which will ultimately provide great advantages for obtaining good coal.

Wood charring zone 14 is exposed to non-condensable gases heated in a recuperator up to 500-600 °, entering through channels (windows) 28 and 29. The recuperator is not shown in the drawing.

Having passed the charring zone, the gas also passes through the final wood drying zone and, together with the vapor-gas decomposition products, leaves the windows 30 to the condensation system 31, where tar and liquor containing acetic acid and alcohols are separated from the gas. The condensation-installation system is usually assumed to be used with continuous charcoal burners, furnaces or American retorts; performance.

The non-condensable gas from the condensation unit is exhausted by sKcraycTOpOM and directed to the consumption in the furnaces, to the recuperator for the co-convection zone, to the cooling of the coal to the cooling zone of the coal and to the side.

A part of the non-condensing gas from the condensation plant, idled to cool the coal, enters the cooling zone through channel 32 and, passing through the coal, goes to the charring zone, where it is mixed with vapor-gas decomposition products.

During exploitation, it is envisaged to conduct an experiment with the extraction of gas and a cooling zone in the window 33 and its subsequent entry for heating to the recuperator for the zone of convexation.

Passing non-condensable gas through a charring zone of wood, according to recent experiments, allows coal output to be increased by 5%.

The subject matter of the invention.

A continuously operating coal-fired kiln, consisting of two communicating at the top of the mines, characterized in that the sloping mines are one with ascending, and the other with a downward flow of fuel being processed and intended for carrying out processes in them - in the first pre-drying, and in second final drying, charring and cooling of coal, have windows 20, 28 and 29 for entering heating gases and windows 21 and 30 for withdrawing them, from which windows 20 and 21 are located respectively at the top and bottom of the first shaft, windows 28, 29 are second p found on the rear bottom of the coal burning zone, and a window 30 in the upper part of the shaft and, in addition, the second shaft has windows 32 and 33 for input and output of the cooling gas.

to the author's testimony of G. L. Nuznetsov and V. A. Ponomarev 48157