JPH07158831A - Combustion method of sludge etc - Google Patents

Abstract

PURPOSE:To collectively effectually utilize energy and hence ensure energy saving by blowing gas turbine exhaust gas into a furnace for combusting dehy drated sludge and the like for promotion of combustion, and obtaining high pressure vapor with produced heat to drive a steam turbine and the gas turbine. CONSTITUTION:A gas turbine 1 is driven by a fuel, and a dynamo 2 is actuated with its driving force. Waste gas (about 550 deg.C, about 15% oxygen) in the gas turbine 1 is blown into a fluidized bed type incinerator 3 to promote combustion of sludge in the incinerator 3. More specifically, incinerator temperature is raised to a temperature of 800 deg.C or higher required for pyrolysis of harmful matter. Further, a heat exchanger 4 is disposed on a high temperature gas exhaust passage of the incinerator 3 to heat and vaporize water passing therethrough, and produced high pressure steam is fed to a steam turbine 5 for working to operate a dynamo 6. Exhaust gas from the incinerator 3 is exhausted from a smokestack 10 through cyclones 7, 8, and an electrical collector 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for incinerating sludge or the like which is designed to save energy.

[0002]

2. Description of the Related Art Generally, in order to treat sludge discharged from a sewage treatment facility, etc., it has been dumped to a landfill. However, it has become difficult to secure landfill sites in recent years, and the volume of sludge was reduced by incineration, etc., and sludge was reused by composting.

[0003]

A fluidized bed type or fluidized bed type incinerator for incinerating dewatered sludge or the like is a method of blowing hot air from the hot air oven into the incinerator, or a hot air oven for starting the incinerator. When hot air is sent from the preheater to start the operation, the air from the air preheater installed in the exhaust gas line of the furnace rises in temperature as the temperature of the furnace rises. It is operated by switching to and continuing the operation.

Since sludge contains odors, harmful substances, etc., it is necessary to burn them at a high temperature of, for example, 800 ° C. or more in order to decompose them. Therefore, the hot air to the incinerator is It requires a high temperature of about 500 ° C. and a blowing force for pushing hot air.

On the other hand, the gas turbine is used for power such as power generation, and the exhaust gas of the gas turbine has hot air of about 500 ° C. and wind power sent by the rotational force of the gas turbine.

In the fluidized bed furnace, the temperature in the furnace is raised to 800 ° C. or higher in order to thermally decompose the sludge, so that high temperature exhaust gas is emitted.

Therefore, an object of the present invention is to provide a method for incinerating sludge or the like that can achieve energy saving by constructing a system that effectively utilizes these energies.

[0008]

The method for incinerating sludge and the like according to the present invention is devised to achieve the above object.
The gas turbine exhaust gas is blown into a furnace for incinerating dewatered sludge or the like to promote combustion, high pressure steam is obtained by the heat generated by the combustion, and the steam is used as power of the steam turbine or the gas turbine.

[0009] Recent sludge has high calorie and calorie level of peat. By injecting hot air of about 500 ° C from the outside, the temperature can be raised to the temperature required for self-combustion and thermal decomposition of sludge. .

Further, the temperature of the turbine exhaust gas of 500 ° C. can be raised to 800 ° C. by incinerating the sludge to promote efficient use of energy.

[0011]

【Example】

Example 1 In FIG. 1, a generator is installed on a drive shaft of a gas turbine (1).
(2) is linked. The gas turbine (1) is driven by the supplied fuel, and the driving force drives the generator (2). The electric power generated by the operation of the generator (2) is used, for example, as a power source for various facilities in the sewage treatment plant.

The dry sludge was put into the fluidized bed type incinerator (3), and the exhaust gas (about 550 ° C., oxygen about 1) of the gas turbine (1)
5%) is blown into the incinerator (3) by utilizing the exhaust power of the gas turbine to accelerate the combustion of sludge in the incinerator, thereby increasing the temperature in the furnace to 800 ° C or higher required for pyrolyzing harmful substances. Up to the temperature of.

Feed water is passed through a heat exchanger (4) arranged in the hot exhaust gas discharge passage of the incinerator (3), high-pressure steam is obtained from this water, and this is sent to a steam turbine (5) to drive the turbine. Drive it. The generator (6) is driven by driving the steam turbine (5).

In FIG. 1, (7) and (8) are cyclones arranged in the discharge passage of high temperature exhaust gas from the incinerator (3), and (9)
Is an electric dust collector, (10) is a chimney, (11) is an incinerator ash conveyor, and (1
2) is incineration ash silo.

In this way, comprehensive effective utilization of energy is achieved and energy saving in the sewage treatment facility is achieved.

Example 2 A heat exchanger arranged in a high temperature exhaust gas discharge passage of an incinerator (3)
High pressure steam is obtained by (4) and sent to the gas turbine (1) to drive the turbine. The generator (2) is operated as described above by driving the gas turbine (1).

Except for this point, the same operation as in Example 1 is performed.

[0018]

The method of incinerating sludge and the like according to the present invention,
Gas turbine exhaust gas is blown into a furnace that incinerates dehydrated sludge, etc. to promote combustion, and high-pressure steam is obtained by the heat generated by combustion, and this steam is used as power for the steam turbine or the gas turbine. Energy saving in sewage treatment facilities can be achieved through effective use.

[Brief description of drawings]

FIG. 1 is a flow sheet showing a first embodiment of the present invention.

[Explanation of symbols]

 (1) …… Gas turbine (2) …… Generator (3) …… Incinerator (4) …… Heat exchanger (5) …… Steam turbine (6) …… Generator

Claims (1)

[Claims] 1. Use of a gas turbine exhaust gas blown into a furnace for incinerating dewatered sludge or the like to accelerate combustion, obtain high-pressure steam by heat generated by the combustion, and use the steam as power for a steam turbine or the gas turbine. A method for incinerating sludge, etc.