JPH0331968B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a waste combustion furnace capable of burning waste such as sewage sludge and municipal waste under appropriate temperature conditions.

(Prior art) Fluidized bed combustion furnaces and stoker furnaces are widely used as waste combustion furnaces used for the above purposes, but in recent years, efforts have been made to reduce the moisture content and increase the calorific value of sewage sludge. Significant problems such as ash fusion, unstable combustion patterns, and increased _NOx emissions were occurring due to increased combustion temperature. For this reason, as seen in fluidized bed boilers, measures have been taken to provide water pipes, water pipe walls, etc. in the furnace to absorb excess heat and reduce the combustion temperature. However, in furnaces that have a large combustion space inside the furnace, such as fluidized bed combustion furnaces and stoker furnaces, even if the heat balance of the entire furnace is balanced, there will be local energy surplus and energy deficit areas within the combustion space. This tends to lead to uneven temperature distribution.
In connection with the fact that the properties of waste are not constant,
Many problems remained, including deterioration of exhaust gas properties such as increased _NOx and increased amount of unburned gas, and difficulty in control.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems and stabilizes the combustion state in the combustion space even when the calorific value or moisture content of waste changes. It was completed with the aim of creating a waste combustion furnace that can be controlled, improve exhaust gas properties, and prevent damage to the furnace due to localized high temperatures.

(Means for Solving the Problems) The present invention includes a combustion regulating body that divides the combustion space into a plurality of upper and lower parts, and is installed inside a combustion space in which waste is burned so that its vertical position can be changed. It is characterized by:

(Example) Next, the present invention will be explained in more detail with reference to an example of a fluidized bed combustion furnace shown in the drawings.

In the first embodiment shown in FIG. 1, 1 is a furnace body of a fluidized bed combustion furnace equipped with an air inlet 2 at the bottom;
4 is a floor surface equipped with a large number of air injection holes, 4 is a burner, and 5 is a combustion space where waste is burned. 6
is a combustion adjustment body mounted inside this combustion space 5 so as to be able to change its position in the vertical direction. This combustion adjustment body 6 is for dividing the combustion space 5 into a plurality of upper and lower parts. As the combustion regulating body 6, a flat or rod-shaped body made of a material with excellent heat resistance such as ceramics, refractories, or metals can be used, but the internal structure may be made of a ceramic honeycomb structure or an aggregate of heat-resistant metal fibers. It is most preferable to use a heat-resistant material through which combustion gases can pass. In this embodiment, such a combustion adjustment body 6 is suspended from the ceiling of the furnace body 1 by a rod 7, and by raising and lowering this rod 7, the vertical position of the combustion adjustment body 6 is adjusted within the combustion space 5. It is made so that it can be changed.

In the second embodiment shown in FIG. 2, a structure is adopted in which a plurality of flat combustion adjusting bodies 6 can be inserted into portions at different heights inside the combustion space 1. Since the insertion depth of each combustion regulator 6 can be freely changed, for example, if only the lower combustion regulator 6 is inserted deeply and the middle and upper stages are pulled out, the combustion regulator 6 is set at a low position. Conversely, if only the upper one is inserted deeply, the combustion adjustment body 6 is set at a high position.

Further, in the third embodiment shown in FIG. 3, the bases of the plurality of combustion adjusting bodies 6 are pivoted at different height positions within the combustion space 5, and they can be stood up vertically or laid down horizontally. By doing so, the combustion adjustment body 6 has a structure in which the height at which the combustion space 5 is partitioned can be changed. Incidentally, such a combustion regulator 6 may carry a catalyst so as to be able to remove toxic substances in the exhaust gas.

(Function) With this configuration, the combustion space 5 in which waste is burned can be divided vertically into a plurality of areas by the combustion adjustment body 6, so the combustion adjustment body 6 can be used to control local high temperatures. If the combustion gas is set slightly below the area where it is likely to occur, the combustion gas will be cooled by absorbing the heat amount by the combustion adjustment body 6, and the heated combustion adjustment body 6 will emit radiant heat into the combustion space 5, causing the furnace to heat up. The entire interior will be heated evenly. As a result,
The temperature of a low temperature area due to energy shortage in the combustion space 5 is increased, and a local high temperature area due to energy surplus is cooled, thereby making the temperature distribution uniform. Further, since the combustion space 5 can be divided into a plurality of upper and lower sections by the combustion adjustment body 6, combustion control for each section can be easily performed. Moreover, in the present invention, the combustion adjustment body 6 is configured to be able to change its vertical position, so that it can be set at the optimal height even if the properties of the waste, such as the calorific value or moisture content, change. This makes it particularly suitable for use in facilities that handle waste of variable properties, such as sewage treatment plants and garbage treatment plants.

In this way, in the waste combustion furnace of the present invention, the combustion state can be stably controlled, so that _NO
This prevents an increase in the amount of gas and unburned gas, and also prevents damage to the furnace wall. Note that the present invention can be freely combined with a conventional water pipe wall, and as described above, a catalyst can be supported on the combustion adjustment body 6 to improve the exhaust gas properties. Further, although only a fluidized bed combustion furnace is shown in the embodiment, the present invention is of course applicable to other types of combustion furnaces such as a stoker furnace and a fluidized bed boiler.

(Effects of the Invention) As is clear from the above description, the present invention can stably control the combustion state in response to changes in the properties of waste, thereby reducing the amount of _NOx generated. , it is possible to reduce the amount of gas in advance, and it is also possible to prevent damage to the furnace wall due to localized high temperatures. Therefore, the present invention greatly contributes to the development of industry as a waste combustion furnace that eliminates the problems of the conventional methods.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view schematically showing a first embodiment of the present invention, FIG. 2 is a cross-sectional view of the second embodiment, and FIG. 3 is a cross-sectional view of the third embodiment. be. 5: Combustion space, 6: Combustion adjustment body.

Claims (1)

[Claims] 1. A combustion adjustment body 6 that divides the combustion space 5 into a plurality of upper and lower parts is installed inside the combustion space 5 for burning waste so that its position in the vertical direction can be changed. waste combustion furnace. 2. The waste combustion furnace according to claim 1, wherein the combustion regulating body 6 is made of a heat-resistant material through which combustion gas can pass.