CN101974344B - A drying process and device for coal humidity adjustment using coke oven flue gas - Google Patents

Abstract

The invention relates to a drying process and a device for humidifying coal by utilizing coke oven flue gas, wherein the coal material firstly passes through a cyclone separator and then enters a vibrated fluidized bed, unsaturated coke oven flue gas is used for humidifying and drying the coal material in the vibrated fluidized bed, and the coke oven flue gas and the coal material carry the coal material with smaller particle size fraction to leave the vibrated fluidized bed and enter the cyclone separator through a heat insulation pipeline after full heat-moisture exchange; in the cyclone separator, coal material entering the cyclone separator from a raw coal inlet can firstly perform heat and moisture exchange with flue gas which still has a drying function and comes out of the fluidized bed in the cyclone separator, so that the raw coal enters the vibrating fluidized bed after being primarily dried in the cyclone separator. The process and the device utilize the coke oven flue gas to carry out humidifying and drying on the raw material coal, can effectively solve the pollution problem caused by the emission of the flue gas generated by coking, and simultaneously use the flue gas as a heat source to dry the wet coal, thereby greatly saving energy, having high heat exchange efficiency, saving energy and reducing emission.

Description

A drying process and device for coal humidity adjustment using coke oven flue gas

technical field

The invention relates to the technical field of heat and moisture exchange, in particular to a process and a device for adjusting the humidity of materials with relatively high humidity, such as coking coal, by using the waste heat of unsaturated coke oven flue gas.

Background technique

At present, the coking coal used in coking plants at home and abroad is transported from the coal yard, mixed with coal to achieve the proportion of coal types, and then crushed and directly loaded into the coke oven. As a result, the humidity of the added coal is about 10%, and the humidity is relatively high. The coke oven needs to heat this part of the water during the coking process, which leads to waste of heat energy. At the same time, the temperature of a large amount of flue gas generated by coking is about 200 degrees Celsius. These flue gases are directly discharged into the atmosphere, which not only pollutes the environment but also wastes energy. It does not meet the requirements of national energy conservation, emission reduction and low-carbon life.

Therefore, it will be a very good topic for environmental protection and energy saving to utilize the heat of flue gas generated by coking as a heat source for humidity control and drying of coal materials.

Contents of the invention

One of the purposes of the present invention is to provide a drying process for coal humidity adjustment using coke oven flue gas, and the second purpose is to provide a drying device for coal humidity adjustment using coke oven flue gas. The coke oven flue gas is used to adjust the humidity and dry the raw coal, which can effectively solve the pollution problem caused by the flue gas emission caused by coking. At the same time, the flue gas is used as a heat source to dry the wet coal, which greatly saves energy and has high heat exchange efficiency. Energy conservation.

To achieve the above object, the present invention is achieved through the following technical solutions:

A drying process that uses coke oven flue gas to adjust the humidity of coal. The coal material first passes through the cyclone separator and then enters the vibrating fluidized bed. In the vibrating fluidized bed, the unsaturated coke oven flue gas adjusts the coal material. Wet drying, coke oven flue gas and coal material undergo sufficient heat and moisture exchange, carry smaller particle size coal material to leave the vibrating fluidized bed, and enter the cyclone separator through the insulation pipe; in the cyclone separator, the flue gas is Intense turbulent motion state, and in the flow, it is strongly mixed with the coal material to perform intense heat and moisture exchange; the coal material entering the cyclone separator from the raw coal inlet can firstly be in the cyclone separator and still have the drying function when it comes out of the fluidized bed The flue gas is exchanged for heat and moisture, so that the raw coal is initially dried in the cyclone separator and then enters the vibrating fluidized bed.

The coke oven flue gas that has fully exchanged heat and moisture with the coal in the vibrating fluidized bed enters the cyclone separator through the insulation pipe; in the cyclone separator, the coke oven flue gas and the particle size of the fluidized bed come out Smaller coal materials and coal materials that enter the cyclone separator from the raw coal inlet are subjected to heat and moisture exchange, and carry smaller particle size coal materials and a small amount of coarse particle coal materials into the gravity separator and bag filter. The granular coal material is separated, and the coal material with a smaller particle size is separated in the bag filter, and the purified flue gas is discharged into the atmosphere through the fan and muffler; the larger particle coal material or part of the aggregate in the cyclone separator enters the vibration After the fluidized bed is dried, it is discharged into the coal preparation and transportation belt through the outlet of the fluidized bed terminal coal material.

The temperature of the unsaturated coke oven flue gas is 200-400°C.

The inlet of the cyclone separator is not only the inlet of the coal material but also the inlet of the flue gas from the coke oven coming out of the vibrating fluidized bed into the cyclone separator.

The inlet of the cyclone separator, that is, the inlet of the coal material or the inlet of the flue gas is an obliquely downward tangential inlet.

The vibrating fluidized bed is a structure with adjustable amplitude and vibration frequency.

The device for realizing the drying process of coal humidity adjustment by using coke oven flue gas includes a vibrating fluidized bed, a cyclone separator, and an insulating pipeline, the outlet of the cyclone separator is connected with the vibrating fluidized bed, and the vibrating fluidized bed The upper part communicates with the cyclone separator through the insulation pipe; the joint between the insulation pipe and the cyclone separator, that is, the flue gas inlet of the cyclone separator is the same as the coal material inlet of the cyclone separator.

An airtight format feed valve 1 is provided between the inlet of the cyclone separator and the raw coal inlet, and an airtight format feed valve 2 is provided at the outlet of the coal material connected to the cyclone separator and the vibrating fluidized bed.

The cyclone separator is also connected to the gravity separator and the bag filter through pipelines, the outlet of the bag filter is connected to the fan, and the outlet of the fan is connected to the muffler; the coal material outlet of the vibrating fluidized bed terminal is connected to the coal preparation and transportation belt.

The lower part of the bag filter is provided with a closed feeding valve three.

Compared with prior art, the beneficial effect of the present invention is:

Today, energy saving and emission reduction has become a consensus in the world. The drying process of the present invention uses coke oven hot flue gas for coal humidity adjustment, which not only utilizes waste heat but also is more environmentally friendly. It can save a lot of heating gas for coking and reduce the emission of coal charging smoke. Thereby realizing energy saving and reducing consumption. At the same time, compared with the traditional simple fluidized bed drying, this process has better fluidization effect, high heat exchange efficiency, reduced equipment size, and achieves the same drying effect. The beneficial effects are described in detail as follows:

1) The vibrating fluidized bed is combined with the cyclone separator. The coal material first enters the cyclone separator for heat and moisture exchange with the flue gas that still has drying function from the fluidized bed, so that the raw coal is initially dried and then enters the vibrating fluidized bed. , to achieve a better fluidization effect, that is, the raw coal undergoes two heat and moisture exchanges with the flue gas in the cyclone separator and the fluidized bed, which can make full use of the waste heat of the coke oven flue gas and greatly improve the heat and moisture exchange efficiency ;

2) The flue gas and coal feed inlets of the cyclone separator are obliquely downward tangential inlets, which have dual functions of feeding flue gas and coal feed, and are characterized by sufficient inlet cross-sections to prevent too much resistance;

3) The airtight feed valve is adopted, the valve body is smooth, it is not easy to stick coal, and the air tightness is good;

4) The vibrating fluidized bed used in the present invention is an adjustable amplitude and vibration frequency structure, and has a frequency modulation and vibration modulation function, so as to adjust the fluidization time of coal material;

5) The present invention is provided with a gravity separator and a bag filter to collect the fine dust coal in the coal and then process it, so as to prevent it from producing a large amount of smoke and dust when the coke oven is charged with coal.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Detailed ways

The technical scheme of the present invention will be further described in detail below in conjunction with the accompanying drawings.

See Figure 1, a drying process for coal humidity adjustment using coke oven flue gas. This process uses a combination of a cyclone separator 2 and a vibrating fluidized bed 1 to perform secondary heat exchange between the flue gas and the coal material, making full use of heat of the coke oven flue gas. The specific process is as follows: the coal material enters from the raw coal inlet 8, enters the cyclone separator 2 through the closed format feed valve 9-1, and enters the vibrating fluidized bed 1 through the interior of the cyclone separator 2. Under the action of the blower 7, unsaturated coke oven flue gas at 200-400°C enters the vibrating fluidized bed 1 from the coke oven flue gas inlet 13 to carry out humidity control and drying of the coal material, and the coke oven in the vibrating fluidized bed 1 After sufficient heat and moisture exchange between the flue gas and the coal material, the coal material with a smaller particle size leaves the vibrating fluidized bed 1 and enters the cyclone separator 2 through the insulation pipe 3; at the same time, at the entrance of the cyclone separator 2, Raw coal (preferably pulverized coal) is sent in by the airtight format feeding valve 9-1, because the cyclone separator 2 inlet has the double function of feeding coal material and entering coke oven flue gas concurrently, so the present invention The inlet 10 of the cyclone separator is in the form of an oblique downward tangential inlet (see Figure 1 for the structure). Due to this structural design, the coal material can smoothly enter the interior of the cyclone separator 2 under the action of the flue gas wind force and its own gravity, and the smaller particles Coal blended in the flue gas can carry out strong turbulent movement together with the flue gas.

The coke oven flue gas that has fully exchanged heat and moisture with the coal in the vibrating fluidized bed 1 enters the cyclone separator 2 through the insulation pipe 3; in the cyclone separator 2, the flue gas flows together with the coal particles, because The air flow in the cyclone separator 2 is strongly turbulent, so the heat exchange is very strong, and the raw coal with high humidity can be well dried for the first time, and the fine coal wet aggregates bonded together can be blown away at the same time. The raw coal that is dried in the cyclone separator 2 is discharged into the vibrating fluidized bed 1 after being scattered in the closed format feeding valve 9-2. At this time, the humidity of the coal material entering the vibrating fluidized bed 1 has dropped, and there are not too many aggregates, so it can be fluidized better, so as to improve the efficiency of fluidized drying.

In the cyclone separator 2, after the coke oven flue gas and the coal with smaller particle size from the vibrating fluidized bed 1 and the coal that enters the cyclone separator 2 from the raw coal inlet 8 undergo heat and moisture exchange, the coal with smaller particle size is carried The coal material and a small amount of coarse coal material enter the gravity separator 4 and the bag filter 5. In the gravity separator 4, the coarse particle coal material is separated by the action of the bin wall vibrator 6. In the bag filter 5, the particle size The smaller coal material is separated, and the separated coal fine material is discharged through the closed format feed valve 9-3 at the bottom of the bag filter 5, and the purified flue gas is discharged into the atmosphere through the fan 7 and the muffler 11; the cyclone separator In 2, larger particle coal material or part of aggregates enter the vibrating fluidized bed 1 to dry and then discharge into the coal preparation and transportation belt through the fluidized bed terminal coal material outlet 12.

As shown in Figure 1, a drying device for coal humidity adjustment using coke oven flue gas, including an adjustable vibrating fluidized bed 1, a cyclone separator 2, and an insulating pipeline 3, the outlet of the cyclone separator 2 is in phase with the vibrating fluidized bed 1 Connection, the upper part of the vibrating fluidized bed 1 communicates with the cyclone separator 2 through the insulation pipe 3; .

An airtight format feed valve 9-1 is provided between the inlet of the cyclone separator 2 and the raw coal inlet 8, and an airtight format feed valve 9-2 is provided at the outlet of the coal material connected between the cyclone separator 2 and the vibrating fluidized bed 1. The cyclone separator 2 is also connected with the gravity separator 4 and the bag filter 5 through pipelines, and the lower part of the bag filter 5 is provided with a closed format feeding valve 9-3.

The outlet of the bag filter 5 is connected to the fan 7, and the outlet of the fan 7 is connected to the muffler 11; the coal material outlet 12 of the terminal of the vibrating fluidized bed 1 is connected to the coal preparation and transportation belt.

The vibrating fluidized bed used in the present invention has an adjustable amplitude and vibration frequency, and has the function of frequency modulation and vibration adjustment, so as to adjust the fluidization time of coal material. The airtight feed valve body used is smooth, not easy to stick coal, and has good airtightness.

The invention maximizes the use of waste heat of unsaturated coke oven flue gas, improves drying efficiency, reduces energy consumption, and reduces humidity of coking coal, thereby improving coke quality and greatly improving economic benefits.

Claims (1)

1. drying process that utilizes coke oven flue gas to carry out the coal damping, it is characterized in that, coal charge enters vibrated fluidized bed again through cyclonic separator earlier, in vibrated fluidized bed, undersaturated coke oven flue gas carries out the damping drying to coal charge, coke oven flue gas and coal charge carry the less coal charge of grade and leave vibrated fluidized bed after carrying out the wet exchange of heat fully, enter cyclonic separator through utilidor; In cyclonic separator, flue gas is strong turbulent motion state, and in flowing with the coal charge intense mixing, carry out the wet exchange of strong heat; The coal charge that is entered cyclonic separator by the raw coal entrance can at first carry out the wet exchange of heat with the flue gas that still has functions/drying that comes out from fluidized-bed in cyclonic separator, make raw coal carry out entering vibrated fluidized bed behind the preliminarily dried in cyclonic separator;

In vibrated fluidized bed, carry out the hot coke oven flue gas that wets after exchanging fully with coal charge, enter cyclonic separator through utilidor; In cyclonic separator, the less coal charge of the grade that coke oven flue gas and fluidized-bed come out and undertaken that heat is wet and exchange by the coal charge that the raw coal entrance enters cyclonic separator after, carry the less coal charge of grade and a small amount of coarse particles coal charge enters gravity separator and sack cleaner, in gravity separator, the coarse particles coal charge is separated, coal charge in sack cleaner that grade is less separates, and the stack gas after purifying enters atmosphere through blower fan and sourdine; Larger particles coal charge or part granule enter vibra fluidized bed drying and enter fully in the coal fortune coal belt by the outlet of fluidized-bed terminal coal charge in the cyclonic separator;

Described undersaturated coke oven flue temperature degree is 200-400 ℃, the entrance of described cyclonic separator be the coal charge entrance also be the waste gas inlet that is entered cyclonic separator by the coke oven flue gas that vibrated fluidized bed comes out, the entrance of described cyclonic separator is that coal charge entrance or waste gas inlet are oblique tangential entrance down, and described vibrated fluidized bed is amplitude and vibrational frequency adjustable structure;

Realize the device of described drying process, involving vibrations fluidized-bed, cyclonic separator, utilidor, the cyclonic separator outlet is connected with vibrated fluidized bed, and vibrated fluidized bed top is communicated with cyclonic separator by utilidor; Utilidor and cyclonic separator junction are that the coal charge entrance of cyclonic separator waste gas inlet and cyclonic separator is same;

Be provided with airtight form feed valve one between the entrance of described cyclonic separator and the raw coal entrance, the coal charge exit that described cyclonic separator is connected with vibrated fluidized bed is provided with airtight form feed valve two; Described cyclonic separator also is connected with gravity separator, sack cleaner by pipeline, and the sack cleaner outlet connects blower fan, and the blower fan outlet connects sourdine; Vibrated fluidized bed terminal coal charge outlet is transported the coal belt and is connected with being equipped with coal, and described sack cleaner bottom is provided with airtight form feed valve three.

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