JPS5945027B2 - Heat treatment method for powdered lignite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for destroying solid carbon-containing materials by decomposition thereof, and more particularly to a method for heat treating fine particles and charcoal.

The present invention is particularly useful in the energy and chemical industries and can be used in the co-production of high calorie solid and synthetic liquid fuels as well as other gaseous and liquid products that are subsequently processed into industrial and chemical feedstocks.

Methods of pyrolyzing or thermally treating particulate solid fuels are well known in the art to produce useful products including solid and liquid products and lower grade products such as heavy tar and pyrolysis condensate.

The combustion heat of heavy tar of about 8400 kcal/kg is the combustion heat of the generated product (the combustion heat is 6400 ~
Although it is known to be higher than 6700 kcal/ky), significant problems exist with its use.

The problem stems from the fact that under normal conditions, tar is a sticky, viscous substance that is not fluid enough to be pumped through a piping system (nor is it solid enough to be loaded onto a vehicle and sent to the consumer). .

Therefore, when heavy tar is used as a liquid boiler fuel, it must be converted to a liquid by heating, which naturally requires additional capital and operating costs.

Moreover, there is the problem of sending heavy tar to consumers.

Therefore, the combustion heat due to the heat treatment of the fuel is 8400 kca
l/kg of product cannot be practically used as fuel.

The pyrolysis condensate also contains about 4.5% phenol dissolved therein, which is a useful product.

However, in order to separate phenol from pyrolysis condensate, complex procedures have to be resorted to, which also require significant capital and operating costs.

Furthermore, after decomposing the phenol from the pyrozene water, it must be purified before being disposed of in the wastewater pond.

As the world's natural energy sources become scarce, the processing of large amounts of low-grade fuels is becoming important.

In particular, the problem of utilizing heavy tar and pyrolysis condensate, which are low-grade products produced in the heat treatment of fuel, becomes more important.

In the i stage, coal is heated to 200-500℃ using a gaseous heat carrier.
temperature for less than 1 second, then the heat carrier is separated from the coal, and in a second stage the coal undergoes intense thermal decomposition by the gaseous heat carrier to form a steam-gas suspension consisting of a solid part and a steam-gas part. heating to a temperature of 500-800°C in less than 1 second to form a vapor-gas fraction, yielding gas, useful liquid products, and lower grade products such as heavy tars and pyrolysis condensate water. Processes for heat treatment of finely divided and charcoal are known in the art (Inventor's Certificate No. 3352)
No. 67).

The realization of the process described above also allows the production of low-grade products such as heavy tars and pyrolysis condensate water, for which there are still unresolved problems in their application, as well as other useful products.

The present invention contemplates a method of thermally treating fine-grained and charcoal, which allows the production of a solid product with a higher heat of combustion than that produced by conventional methods, with a power input equal to that of conventional methods. Guaranteed.

In the first step, the present invention uses coal as a gaseous heat carrier to
heating to a temperature of 500° C. for less than 1 second, after which the waste heat carrier is separated from the coal; in the second stage, intense pyrolysis of the coal takes place with the gaseous carrier, containing a solid part and a steam-gas part; 500-8 at which a vapor-gas suspension is formed
Heating to a temperature of 00°C in less than 1 second, condensing the vapor-gas part to obtain gas, useful liquid products and also separating low-grade products such as heavy tars and pyrolysis condensate water therefrom. According to the present invention, in the second heating stage, the heat treatment low grade products of the fine particulate and charcoal are introduced into the flow of a gaseous carrier containing air oxygen. Sprayed.

It is advantageous to feed heavy tar into the stream of gaseous heat carrier, the oxygen content of which is sufficient to carry out the pyrolysis treatment of the heavy tar at a predetermined temperature.

The pyrolysis of the heavy tar liberates volatile components which are combusted, thereby increasing the temperature of the gaseous heat carrier.

In addition, a solid portion is formed which is a high calorie fuel.

It is good practice to feed pyrolysis condensate water into the stream of the gaseous heat carrier, along which the gaseous heat carrier is first fed with pyrolysis condensate water and then with heavy tar.

This prevents the need to purify the pyrolysis condensate before disposal to the pool.

Furthermore, the organic solvent dissolved in the pyrolysis condensate water can be converted into useful products.

The invention will now be described with reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings.

When realizing the method for thermally treating coal in granular form, an apparatus is used which includes a chamber 1 for the first stage heating of the coal.

The device has a hopper 2 which communicates with a chamber 1 through a turnstile feeder 3.

Connecting pipe 4 of a device (not shown) for supplying a gaseous heat carrier
touches chamber 1 in the tangential direction.

For the discharge of the waste gas heat carrier, a pipe 5 is installed coaxially in the chamber 1 and communicating with a cyclone (not shown).

A chamber 7 used for second stage heating of the fuel is connected to chamber 1 through a feeder 6.

Adjacent to the chamber 7 used for the second stage heating of the coal there is a device 8 for conveying a gaseous heat carrier to the chamber 7, the stream of gaseous heat carrier being fed with a low grade product.

The device 8 is a piping system 9 tangentially adjoining the chamber 7 used for the second stage heating of the coal.

The piping system 9 is equipped with a chamber 10 in which fuel is combusted to form a stack gas, a chamber 11 for supplying pyrolysis condensate through an atomizer 12 and a chamber 13 for supplying heavy tar through an atomizer 14.

A burner 15 is installed in the chamber 10, which is used to burn fuel mixed with air and oxygen.

and for discharging the steam-gas mixture resulting from the pyrolysis of the coal, the chamber 7 used for the second stage heating of the fuel is provided with a pipe 16 located coaxially therein and communicating through a piping system to a cyclone (not shown). be done.

Furthermore, the chamber 7 used for the second stage heating of the charcoal is equipped with a turnstile regulating device 17, which is used to discharge the solid product obtained from the chamber 7 as well.

According to the present invention, a method of heat treatment of fine particles and charcoal is realized as follows.

The fine granular charcoal having a particle size of less than 1 u is preheated to about 110°C for drying, and then transferred to the hopper 2 by the feeder 3.
The dry charcoal is fed into the chamber 1 used for the first stage of heating.

At the same time, an oxygen-free heat carrier in the form of a stack gas having a temperature not lower than 500° C. is introduced into chamber 1 through connecting pipe 4 .

The heat carrier then enters tangentially into the chamber 1 used for the first stage heating of the charcoal and attracts the fine-grained charcoal particles.

Under the action of centrifugal force and gravity, the charcoal particles are thrown towards the walls of the chamber and descend in the vortex.

The fine granules and charcoal are heated to a temperature of 200 to 500°C by a heat carrier.

The exhaust gaseous heat carrier cooled to a temperature of approximately 350° C. is discharged through pipe 5 into a cyclone (not shown).

The finely divided and charcoal fraction carried by the heat carrier is separated therefrom in a conventional manner.

The feeder 6 is connected to a chamber 1 used for heating the charcoal in the first stage and a chamber 7 used for heating the charcoal in the second stage.
supply to.

Simultaneously with the coal, a gaseous heat carrier is fed through the device 8 into the chamber γ used for the second stage of heating.

According to the invention, a low-grade product is supplied to the gaseous heat carrier obtained by combustion of a gaseous fuel and by the formation of a stack gas.

This procedure is performed as follows. Combustible gas or other fuel mixed with air oxygen is supplied to the burner 15.

More than 50% of the combustible gas is combusted in the chamber 10, thereby forming a gaseous heat carrier containing air oxygen.

Approximately 50% of the combustible material burns in chamber 10 and forms a heat carrier, so that the temperature in this chamber reaches approximately 1200.degree.

It should be noted that the combustion process and temperature in the chamber 10 in which the formation of the heat carrier takes place is regulated in a conventional manner and with conventional equipment, and will therefore be clear to a person skilled in the art.

From chamber 10, where the formation of the heat carrier takes place, the gaseous heat carrier enters chamber 11, which is used for pyrolysis condensate treatment.

At the same time, pyrolysis condensate water is fed through the atomizer 12 to the stream of gaseous heat carrier.

In the chamber 11 used for the treatment of the pyrolysis condensate water evaporation and the oxidative pyrolysis of the organic substances dissolved therein, in particular phenol, take place.

During thermal decomposition of organic substances, some of them are converted, others are burned, and other parts are deposited as carbon on the fine particles of coke obtained.

Due to the treatment of pyrolysis condensate, the temperature of the gaseous heat carrier is approximately 1
000℃.

A gaseous heat carrier having a temperature of 1000° C. is fed to the chamber 13 in which the treatment of heavy tar takes place.

Heavy tar constituting the liquid after being heated is continuously fed into the chamber 13 through an atomizer 14 .

Owing to the high temperature and the oxidizing medium (the gaseous heat carrier stream contains oxygen), an oxidative pyrolysis of the heavy tar takes place in the chamber 13.

In this case, a partial conversion of the liquid organic compound occurs and the gas is combusted.

As a result of the afterburning of the gas and the partial combustion of the combustible material separated after decomposition of the heavy tar, the temperature of the heat carrier increases to 1200°C.

The gaseous heat carrier, together with the pyrolysis condensate and the particles contained therein obtained as a result of the heat treatment of the heavy tar, enters the chamber 7 used for the second stage heating of the coal, where the gaseous heat carrier is The oxygen has completely reacted and the heat carrier mixes with the charcoal being treated and supplied by the feeder 6.

The solid particles of charcoal are then rotated by the gas flow and moved from the center of the chamber 7 to its periphery through the hot gaseous heat carrier.

The gaseous heat carrier gives the heat to the charcoal and transfers it to 500~
Heat to a temperature of 800°C.

In this case, intense thermal decomposition of the charcoal takes place, resulting in a steam-gas suspension containing a solid product in particulate form (coke) and a steam-gas mixture.

The solid product obtained is discharged by means of a turnstile conditioning device 17 from the chamber 7 used for the second stage heating of the charcoal.

At the same time, the resulting vapor-gas mixture is discharged through tube 16 to a cyclone (not shown) to remove solid particles.

The purified vapor-gas suspension is sent to condensation to produce useful liquid products from which lower grade products in the form of heavy tars and pyrolysis condensate water are separated.

The low-grade products such as heavy tar and pyrolysis condensate thus obtained are sent to chambers 11 and 13, respectively, and fed into the stream of gaseous heat carrier.

Example: Calorific value: 3500 kcal/9, water content: 32-3
8%, ash content 8% and sulfur content 0.5% and the charcoal was pulverized to a particle size of less than 1 mm and preheated to a temperature of 110°C.

The resulting charcoal was sent to chamber 1 for heating in a vortex by a gaseous heat carrier such as a stack gas having a temperature below 500°C.

In less than 1 second (approximately 0.3 seconds), the coal was heated to a temperature of 200-500° C., the temperature at which thermal decomposition of the coal begins.

The coal was heated so quickly that its composition remained virtually unchanged.

This is because 1 ton of coal being treated produced only 20 kg of lumps consisting of pyrolysis condensate, gas and associated coal.

An exhaust gaseous heat carrier having a temperature of approximately 350° C. was separated from the heated coal.

The coal heated to the temperature of the onset of pyrolysis was sent to the chamber 7 used for the second stage heating of the coal, where it was heated by a gaseous heat carrier having a temperature of about 1000°C.

In a period of 0.3 seconds, the charcoal was heated to a temperature of 500-800°C.

According to the invention, 500 kg of pyrolysis condensate water per 10 kg of combustible gas per 10 kg of gaseous heat carrier stream containing 100 kg of air.
kg was supplied.

Simultaneously with the combustion of the gas, evaporation of water and separation and oxidative pyrolysis of the organic substances dissolved in the water took place.

Thus, although the evaporation of water generally requires about 600 kcal/kg, in this case due to the combustion of the phenol dissolved in the pyrolysis condensate, the energy consumption for evaporation is only 150-200 kcal/kg. It was just that.

Moreover, thermal decomposition of phenol resulted in the formation of insoluble residues.

75 kg of finely divided heavy tar were charged into chamber 13 through an atomizer 14 in order to feed the gaseous heat carrier.

Due to the high temperature and the oxidizing medium (the gaseous heat carrier stream contained air oxygen), thermal decomposition of the heavy tar, partial conversion of the liquid organic compounds and combustion of the heat carrier gas occurred.

Thermal decomposition of heavy tar resulted in the formation of solid parts in the form of coke particles.

In this case, the separated combustibles were partially combusted, so that the temperature of the gaseous heat carrier rose to approximately 1200.degree.

The heat carrier containing the products of the heat treatment of the fuel is therefore sent to the chamber 7 used for the second stage of heating, in which chamber the coal is heated to a temperature of 500-800 °C in which the coal is decomposed by the gaseous heat carrier obtained.
, thus producing a vapor-gas suspension containing solid product in particulate form and a vapor-gas mixture.

The vapor-gas mixture (= parts) was sent to purification condensation to obtain gas, useful liquid products, and from which low-grade products such as heavy tar and pyrolysis condensate water were separated.

The resulting low grade product was fed to chambers 11 and 13 for processing.

The solid product obtained at the same time was removed by means of a conditioning device 17 and from the chamber 7 used for the second stage heating of the charcoal.

The implementation of the proposed method, pyrolysis treatment of heavy tar and pyrolysis condensate, yielded 60-80% solid product, ie 75 to 50 kg of heavy tar.

A solid product with a heating capacity of approximately 8200-8400 kcal/kg was deposited on the finely divided and charcoal heat-treated product.

The products thus obtained also include charcoal heat treatment products and heavy tar pyrolysis products.

The exothermic capacity of the above first product is about 6400-6700
kcal/kg, and the calorific capacity of the above second product is about 8200-8400 kcal 7kg, so the overall calorific capacity is about 6930 kcal 7kg, which is 6400-670 kcal obtained by the conventional method.
0 kcal 230 kcalAg higher than the solid product with a calorific capacity of 7 kg.

This results in an 18% increase in solids fraction. Also, the yield of solid products with increased heating capacity is achieved without any increase in power consumption, ie by combustion of combustibles that are part of the composition of the low-grade products.

Charcoal as the fuel for the process and is for illustrative purposes only in this particular example.

However, it will be apparent to those skilled in the art that any other fuel can be used as the processing material.

With this in mind and in accordance with conventional conditions, processing of the charge fuel and low grade products is carried out at operating conditions of temperature and time maintained in a conventional manner.

[Brief explanation of drawings]

The figure shows equipment for heat treatment of fine grains and charcoal. 1... First stage heating chamber, 7... Second stage heating chamber, 10... Stack gas formation chamber, 11
...Pyrolysis condensed water supply chamber, 13...Heavy tar supply chamber.

Claims (1)

[Claims] 1. In the first stage, powdered lignite is heated to 200-500"C in less than one second by means of a gaseous heat carrier.
, and then the heat carrier is separated from the lignite, and then in a second step the lignite is heated by the gaseous heat carrier to a temperature of 500-800° C. in less than 1 second, and this heating The lignite is violently pyrolyzed to produce a vapor-gas suspension containing a solid part and a vapor-gas part, then the vapor-gas part is condensed to obtain gas and liquid products, and then the liquid In a process for heat treatment of powdered lignite, which involves separating lower products such as heavy tar and heat-generated water from the product, the second stage of heating separates the lower products of the heat treatment of powdered lignite. A process for the heat treatment of pulverized brown coal, characterized in that it is sprayed into a stream of gaseous carrier containing atmospheric oxygen. 2. A method according to claim 1, characterized in that heavy tar is fed into the stream of gaseous heat carrier to cause its thermal decomposition. 3. The gaseous heat carrier is supplied with thermally generated water, and the gaseous thermal carrier is supplied first with the thermally generated water and then with the heavy resin along the flow, or The method described in Section 2.