SU1703908A1 - Method of operation of boiler plant - Google Patents

Abstract

The invention relates to a power system and can be used in the combustion in boiler plants of solid sulfur-containing fuel having ash of the basic composition. The purpose of the invention is to increase the economics by reducing the ballast component of the ash. This is achieved by the fact that before returning the residue caught by the ash collector 2 ash into the furnace chamber 8, particles with a size larger than the maximum particle size of the fly ash are additionally separated from this ash residue. Thus, in the ashes returned to the furnace, a reduction in the ballast component is achieved, which makes it possible to increase the efficiency of the boiler plant. 1 il.

Description

UNION OF SOVIET

SOCIALIST

REPUBLIC

1703908 A1 (505 F 22 B 33/18 ____________.

STATE COMMITTEE

BY INVENTIONS AND DISCOVERIES

AT SCST USSR

DESCRIPTION OF THE INVENTION

TO AUTHOR'S CERTIFICATE '

(21) 4772161/06 (22) 12.19.90 (46) 01/07/92. Bull. No 1 (71) Tomsk Polytechnic Institute named after

S. M. Kirova (72) A.N. Merzlyakov, A.S. Zavorin and O.I. Budilov (53) 621.181.2 (088.8) (56) USSR Copyright Certificate

Ns 1574979, cl. F 22 B 33/18, 1988.

(54) METHOD OF OPERATION OF A BOILER PLANT (57) The invention relates to a power system and can be used for burning solid sulfur-containing fuel in boiler plants having basic ash. The purpose of the invention to increase efficiency by reducing the ballast component of the ash. This is achieved by the fact that before returning to the furnace chamber 8 the remainder of the ash caught by the ash collector 2, particles with a size exceeding the maximum particle size of fly ash are further separated from this ash residue. Thus, in the ash returned to the furnace, a decrease in the ballast component is achieved, which allows to increase the efficiency of the boiler plant. 1 ill.

1703908 A

The invention relates to a power system and can be used in thermal power plants when burning solid sulfur-containing fuels in boiler plants.

The aim of the invention is to increase efficiency by reducing the ballast component of the ash.

The drawing shows a schematic diagram of a boiler plant for implementing the proposed method.

The boiler installation comprises a boiler unit 1, an ash collector 2, a smoke exhaust 3, an air separator 4, a hopper 5 and a system for determining and comparing the maximum sizes of ash particles with an actuator 6. The boiler unit 1 includes a furnace containing a horizontal cyclone combustion chamber 7 and a vertical chamber 8 cooling screens 9 and placed in the lowering gas duct of the boiler unit 1 of the surface 10. connected to a vibrator 11 of known design. The boiler unit 1 is connected to the exhaust fan 3 through an ash collector 2. To an air separator 4, which is a vertically arranged cylindrical body with nozzles for removing small 12 and large 13 classes of particles, an ash collector 2 is connected through a supply nozzle 14 and through the nozzle 15 the air duct 16 with a regulating the valve 17. The pipe 15 is connected to the separator 4 below the connection point of the pipe 14. The pipe 12 of the separator 4 is connected by an ash pipe 18 through the discharge nozzle 19 to the furnace chamber 8, and the pipe 13 to the hopper 5. At the exit of the furnace and (in front of screen 9) a dust collection tube 20 of known construction is installed. An ash collector 21 and a maximum particle size detector 22 are connected in series with the dust collection tube 20. An ash collector and a maximum particle size detector 24 are connected in series to the ash duct 18. Fans 25 and 26 are connected to ash collectors 21 and 23, to detectors 22 and

- adjusters 27 and 28, connected to the block 29 of the comparison. The output unit 29 is connected to the control unit 30 of the actuator 6 of the valve 17.

The method of operation of the boiler installation is as follows.

In the cyclone combustion chamber 7 serves a crushed solid sulfur fuel having ash of the main composition, and an oxidizing agent. As a result of combustion, slag melt, fly ash and flue gases are formed. Liquid slag flows from chamber 7 to chamber 8. drains onto it underneath and is removed through a notch to a slag removal channel (not shown). Fly ash with the flue gases is discharged from the chamber 7 into the cooling chamber 8 and through the outlet window of the furnace through the convective gas duct of the boiler unit 1 enters the ash collector 2. The flue gases cleaned from ash are fed into the chimney 3 (not shown) and then discharged into the atmosphere. A portion of fly ash is deposited on surface 10, forming aeolian deposits. The deposits have a basic composition (in accordance with the composition of the ash of the combusted fuel) and, therefore, are intensively sulfated, desulfurizing the flue gases.

Periodically (as sulfate deposits) surface 10 is subjected to vibration cleaning provided by a vibrator

11. At the same time, large particles of sintered and sulfated ash (particles formed during the destruction of ash deposits) enter the dust collector together with the flue gases 2. At the outlet of the furnace, part of the volatile combustion products is taken from the stream with a dust pipe 20. The selected gases are removed from the dust collector 21 and fan 25 is discharged into the atmosphere.

The collected ash from the ash collector 21 is fed to the detector 22. The operator determines the maximum particle size in the collected ash and provides an electric signal proportional to the determined size to the collector 27. Ash and air are simultaneously fed into the air separator 4: ash - from the ash collector 2 through the nozzle 14, and air - from the compressed air line (not shown) through the duct 16 with the valve 17 through the nozzle 15. As a result, the ash is classified by size. Fine ash, together with the air supplied through the pipe 15, enters through the pipe 12 in the ash pipe 18 and then through the nozzle 19 is discharged into the chamber 8 of the furnace. Large particles of ash fall out of the separator 4 through the nozzle 13 into the collection hopper 5. From the ash pipe 18, a part of the air mixture, which is further supplied to the ash collector 23, is discharged by known technology.

From dust collector 23, dust-free gases are discharged by the fan 26 into the atmosphere, and the collected ash is fed to the detector 24. The operator determines the maximum particle size in the collected ash and provides an electric signal proportional to the determined size to the collector 28. The signals from the setters 27 and 28 are received in block 29 of the comparison. From block 29, a signal proportional to the difference between the signals of the setpoints 27 and 28, enters the control unit 30. The node generates a command and transfers it to the actuator 6. reversing it. The actuator 6. by opening or closing the valve 17, changes the volume of air 5 supplied to the separator 4 and thereby the boundary particle size by which the separated ash is divided. As a result, particles with a size exceeding the maximum particle size of 10 fly ash are separated from the ash furnace returned to the chamber 8.

The collection of large particles of ash is carried out in the hopper 5. The return of ash from the ash collector 2 into the chamber 8 of the furnace continues until then. until it is completely sulfated 15 and passes into the discharge of large particles. The waste thus obtained ·> slivoszhiganiya from the prefabricated hopper 5 can be used to obtain products related to energy production 20 necessary for the national economy (for example, can be used to organize sulfate production).

Example. When a fuel crusher 25 with a maximum particle size of 5 mm is fed into the cyclone combustion chamber 7 of the furnace, the maximum particle size in the fly ash is 0.8 mm, ‘and in the ash from the ash collector, 2 12 mm. Accordingly, particles larger than 0.8 mm are separated from the ash from the ash collector 2. The remaining ash with particle sizes not exceeding 0.8 mm is returned to the furnace cooling chamber 8.

Thus, in the ash returned to the furnace, a decrease in the ballast component is achieved.

Claims (1)

Claim The method of operation of the boiler plant by supplying solid fuel for combustion in the furnace, cleaning the flue gases from the ash, separating particles from the trapped ash with sizes larger than the maximum particle size of the fuel supplied to the furnace, and returning the trapped ash to the furnace, characterized in that. in order to improve efficiency by reducing the ballast component of the ash, before returning to the furnace from the residue of collected ash, particles that are larger than the maximum particle size of the fly ash should be additionally separated.