JP2769271B2 - Garbage incineration equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION In recent years, in order to effectively use the heat energy generated in a refuse incinerator, a generator that generates heat by exchanging heat contained in exhaust gas generated from the incinerator with a waste heat boiler has been developed. Municipal garbage incinerators equipped have been attracting attention.
The present invention includes a waste heat boiler that recovers waste heat from exhaust gas generated in an incinerator and generates steam, and a power generation device that drives a turbine with the generated steam to generate power, and the power generation device The present invention relates to a refuse incinerator provided with a combustion type superheater for superheating steam in a steam supply passage to a steam supply passage.

[0002]

2. Description of the Related Art Conventionally, air sucked from a dust pit for collecting dust is heated by steam generated in the waste heat boiler and supplied to an incinerator as air for primary combustion.

[0003]

However, in the case of using the steam generated in the waste heat boiler, it is necessary to sufficiently heat the air for primary combustion when the quality of the waste is poor and the amount of generated steam is reduced. However, there was a disadvantage that the combustion state was not sufficiently improved. An object of the present invention is to solve the conventional drawbacks described above, to effectively utilize the heat energy of the exhaust gas of the combustion type superheater, and to provide an immediate effect for avoiding a decrease in the combustion state at the time of deteriorating the refuse quality of the incinerator. An object of the present invention is to provide a garbage incinerator having a certain measure.

[0004]

In order to achieve this object, a first characteristic configuration of a refuse incinerator according to the present invention is to heat primary combustion air supplied to the incinerator with exhaust gas from the combustion type superheater. In that a heat exchanger is provided. The second characteristic configuration is to provide a heat exchanger using exhaust gas from the combustion type superheater as a heat source, and to mainly supply air heated by the heat exchanger when the combustion state of the incinerator deteriorates. In addition, control means is provided for supplying air to the incinerator as primary combustion air, and when the combustion state of the incinerator is good, supplying the air mainly as combustion air to the combustion superheater.

[0005]

According to the first characteristic configuration, the primary combustion air supplied to the incinerator is heated by using a heat exchanger utilizing the heat energy of the exhaust gas of the combustion type superheater,
Even if the combustion state in the incinerator deteriorates, continuous deterioration of the combustion state is avoided by stably supplying high-temperature primary combustion air. According to the second feature, the supply destination of the air superheated by the heat exchanger is controlled by the control means. In other words, when the combustion state of the incinerator deteriorates, it is mainly supplied to the incinerator as primary combustion air to quickly recover a good combustion state, and when the combustion state of the incinerator is good, It is mainly intended to improve the fuel efficiency of the combustion type superheater by supplying it as combustion air to the combustion type superheater.

[0006]

According to the present invention, it is possible to effectively utilize the thermal energy of the exhaust gas of the combustion type superheater to avoid a decrease in the combustion state when the incinerator degrades the refuse quality, and to generate a stable power. It has become possible to provide a garbage incinerator having an immediate action.

[0007]

Embodiments will be described below. Garbage incineration equipment
As shown in FIG. 1, a stoker-type incinerator 1 for incineration of municipal garbage, an exhaust gas treatment device 2 for purifying exhaust gas generated from the incinerator 1, and a power generation device 3 for generating electricity using heat of the exhaust gas And so on.

The incinerator 1 includes a hopper 4 for receiving the incinerated material, a pusher Pu for injecting municipal garbage, which is an incinerated material in the hopper 4, from the lower end into the furnace, and an incinerator charged by the pusher Pu. A stoker S for drying, burning and ashing is provided while the material is stirred and conveyed, and a secondary combustion space 7 is formed in the upper space of the stoker S in order to complete the combustion of the unburned gas. A waste heat boiler for providing a secondary combustion air supply section 9 for supplying secondary combustion air to the space 7 facing the space 7 and for recovering thermal energy of the combustion exhaust gas in a space 8 downstream of the space 7. 6 are provided.

The exhaust gas treatment device 2 comprises a bag filter 12, a smoke washing device 13 and the like provided in the middle of a flow path from an exhaust gas passage 10 provided downstream of the space 8 to a chimney 11.

The power generator 3 comprises a steam turbine 14 and a generator 15 connected to its output shaft.
About 100 kgf / c generated from the waste heat boiler 6
High-pressure steam of m ₂ , 310 ° C. is led to a combustion type superheater 17 via a steam supply line 16 which is a main steam path, and after being superheated to about 500 ° C. by the combustion type superheater 17, is supplied to the steam turbine 14. I do. The steam supplied to the steam turbine 14 and used for generating all the energy is cooled by a cooler 18 through an exhaust path 14c and collected, and the waste heat boiler 6
Circulated through a condensate channel 25 circulating through A part of the steam supplied to the steam turbine 14 is extracted from the extraction passages 14 a and 14 b after a part of the energy is supplied to the power generation, and is supplied to the feed water preheater 19 provided in the condensate passage 25.
It is led to.

A branch 20 is provided in the steam supply path 16, and a pressure reducing mechanism 20a comprising a pressure reducing valve for reducing a part of the steam generated in the waste heat boiler 6 to 40 kgf / cm ₂ is provided in the branch 20. , An accumulator A for accumulating depressurized steam, an air passage 21 for venting the steam from the accumulator A, and a bleed passage 14 a for the turbine 14.
And are connected.

In the waste heat boiler 6, not only does the steam amount of several percent fluctuate frequently in a cycle of several seconds, but also,
When the incineration condition in the incinerator 1 is good (flammable garbage is stably supplied), the amount of steam generated in the waste heat boiler 6 increases as a whole, and the incineration condition deteriorates (moisture content). (A large amount of unburnable refuse is supplied), the amount of steam generated in the waste heat boiler 6 is reduced as a whole, and the steam amount fluctuates by several tens of percent due to a period of tens of minutes. Therefore, when surplus steam is generated in response to a change in the steam amount of several tens percent due to a period of tens of minutes, the surplus steam is adjusted by adjusting the flow control valve 22 provided in the steam supply path 16 to the accumulator. If the generated steam is insufficient in the waste heat boiler 6, the accumulation of the steam in the accumulator A is stopped, and the extraction amount adjusting valve 23 provided in the extraction passage 14 a of the turbine 14 is operated. The amount of heat supplied to the turbine 14 is squeezed to effectively use the power for power generation, and the ventilation amount adjustment valve 24 provided in the ventilation path 21 is opened to release the steam (24 kgf / cm ₂ ) accumulated in the accumulator A. The air is supplied to the bleed passage 14a.

The combustion type superheater 17 includes a gas burner 17
a from the combustion flow of the fuel gas supplied from
d, which superheats the steam from the waste heat boiler 6 passing therethrough. A water spray mechanism 17f for correcting and stabilizing the steam flow rate by means of water spray is provided, while cooling for protecting the side wall of the heat exchange section. A part of its own exhaust gas is circulated and supplied as a gas through a cooling circuit 17c provided with a flow control damper 17e, and the remaining exhaust gas is used for secondary combustion of the incinerator 1 through a combustion air supply path 30. Supply as air. The combustion air supply path 30 is branched, and a part of the exhaust gas at about 400 ° C. is led to the heat exchanger 31 so that air at room temperature is heated to about 250 ° C.
To increase the combustion efficiency of the combustion type superheater 17 by supplying the air as combustion air to the combustion type superheater 17, and a part of the air heated by the heat exchanger 31 is removed from the incinerator. A combustion air supply passage 32 for supplying as primary combustion air is provided. The combustion air supply passage 32 is provided with a damper 33 for adjusting the flow rate. The damper 33 is opened based on a value of a steam amount sensor 17b provided at a steam inlet to the combustion type superheater 17. Control means 3 for controlling the degree of temperature so as to quickly avoid deterioration of the combustion state in the incinerator 1 and control the combustion state to be stable.
4 are provided. In other words, when the decrease in the generated steam amount is detected by the steam amount sensor 17b, the dust quality is reduced, or
Judging that the combustion state has deteriorated due to the decrease in the amount of dust, the opening degree of the damper 33 for adjusting the flow rate is largely adjusted, and the amount of dust supplied is increased by the transport control means (not shown).
The amount of fuel supplied to the gas burner 17a is increased, the fluctuating steam amount is stabilized by water spray, and when the increase in the amount of generated steam is detected by the steam amount sensor 17b, it is determined that the combustion state is good, and the flow rate adjustment is performed. The opening degree of the damper 33 is maintained or adjusted to a small value, and low fuel consumption combustion is aimed at by reducing the amount of fuel supplied by supplying high-temperature combustion air to the gas burner 17a. That is, the damper 33, the steam amount sensor 17b, and the control means 34 constitute a primary combustion air supply amount adjusting means C.

The case where a part of the air heated by the heat exchanger 31 is used as the primary combustion air of the incinerator 1 has been described. In this case, in addition to the primary combustion air described above,
A supply path 35 for supplying the primary combustion air at normal temperature to the stoker S is provided.

In the above embodiment, the control means 34 supplies the air superheated by the heat exchanger 31 to the incinerator 1 as primary combustion air when the combustion state of the incinerator 1 deteriorates. Although it has been described that when the combustion state of the incinerator 1 is good, the incinerator 1 is controlled to be supplied as combustion air to the combustion type superheater 17, but the distribution is not particularly limited. It can be set appropriately according to the scale of the furnace 1 and the scale of the combustion type superheater 17.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a garbage incinerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Incinerator 3 Power generator 6 Waste heat boiler 14 Turbine 16 Steam supply path 17 Combustion superheater 31 Heat exchanger

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-63904 (JP, U) JP-A-3-96549 (JP, U) JP-B 54-35601 (JP, B2) (58) Survey Field (Int.Cl. ⁶ , DB name) F22B 1/18

Claims (2)

(57) [Claims] A waste heat boiler (6) for recovering waste heat from exhaust gas generated in an incinerator (1) to generate steam and a power generator (3) for driving a turbine (14) with the generated steam to generate power. ), Wherein a combustion type superheater (17) for superheating steam in the passage is provided in a steam supply path (16) from the waste heat boiler (6) to the power generator (3). Te, the exhaust gas from the combustion superheater (17) heat exchanger for heating air (31) and is provided, on the incinerator (1)
Said heat exchanger (31)
The incinerator as the primary combustion air
A garbage incinerator configured to supply to (1) . 2. A waste heat boiler (6) for recovering waste heat from exhaust gas generated in an incinerator (1) to generate steam, and a power generator (3) for generating electricity by driving a turbine (14) by the generated steam. ), Wherein a combustion type superheater (17) for superheating steam in the passage is provided in a steam supply path (16) from the waste heat boiler (6) to the power generator (3). A heat exchanger (31) that uses exhaust gas from the combustion type superheater (17) as a heat source; and heats the air heated by the heat exchanger (31) to the combustion state of the incinerator (1). If the incinerator (1) deteriorates, it is mainly supplied to the incinerator (1) as primary combustion air. If the combustion state of the incinerator (1) is good, the air is mainly supplied to the combustion type superheater (17). A refuse incineration device provided with control means (34) for supplying the air as combustion air.