JPS6080021A - Burning control device of refuse incinerator - Google Patents

Abstract

PURPOSE:To reduce the NOX concentration less than the designed value without deteriorating the burning safety by a method wherein the reducing limit of an air quantity is controlled to be not less than the lower limit value of the O2 concentration when an exhaust NOX concentration is reduced by adjusting a burning air quantity. CONSTITUTION:An NOX constant control device 3, an O2 constant control device 6 and an O2 constant control device 8 are controllers for outputting operational signals to control so that the deviation between an NOX concentration setting value 1, a normal O2 concentration setting valve 4, a lower limit O2 concentration setting value 7 and an NOX determined value 2, an O2 determined value 5 are made to be zero. The output operational signals from the NOX constant control device 3 and the O2 constant control device 6 are made to be selected and outputted the lower value of a burning air quantity by a lower signal selector 9. Further, the output is inputted to a higher signal selector 10 together with the output operational signal of the O2 constant control device 8. Thereupon, a higher value is selected in the same manner, finally, a burning air quantity operational signal 11 is outputted, thus, the actual air quantity control is performed.

Description

[Detailed Description of the Invention] In recent years, there has been a need for garbage incinerators to suppress the NO% concentration of exhaust gas to a predetermined value or less using combustion control alone without adding denitrification equipment. It was difficult to respond appropriately to the ever-changing combustion conditions by making changes alone. Therefore, it has been desired to automate this process.

On the other hand, the amount of combustion air is a means of reducing NOx concentration, and the correlation between NOx and oxygen concentration supports its effectiveness as an operating end.
Because it is directly linked to changes in combustion conditions and is dangerous,
Automation was slow.

The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and provides a waste incinerator combustion control device that can reduce NO8 concentration to a predetermined value or less without impairing combustion stability. The exhaust N is reduced by adjusting the amount of combustion air.
Regarding a waste incinerator combustion control device that aims to maintain stable combustion by limiting the air volume reduction limit to not fall below the lower limit of OL concentration when reducing the OL concentration by 1 degree, the signal selector is 0 control and λ NO2 control by selecting the optimal signal from the operation signals from the normal 0 control loop, lower limit OL control loop, and NOx control loop and adjusting the amount of combustion air. It was designed to be able to achieve both.

An embodiment of the present invention will be described below with reference to the drawings. In the embodiment shown in the drawings, the NOx constant control device 3, the OL constant control device N6, and the OL constant control device 8 each have a NoX concentration setting value 1 and a normal OL concentration setting value 4. , lower limit O1 concentration setting value 7
This is a controller that outputs an operation signal so that the deviation between the NOx actual measurement value 2 and the OL actual measurement value 5 becomes zero. The output operation signals of the NOx constant control device 3 and the NOx constant control device 6 are selected by a low signal selector 9 to output the low combustion air amount.

This output is also 0. The output operation signal of the constant control device 8 is input to the high signal selector lO, and the high signal is similarly selected.
It is output as the final combustion air amount operation signal 11, and the actual air amount operation is performed.

Here, for example, NOx concentration setting value 1 is 1ooppm.

Normally 0□Density set value 4 is set to 7%, and lower limit 0□Density set value 7 is set to 6%. Normally, the air amount is adjusted so that 0□ is around 7%, and when NOx is about to exceed 1100 pp, a low air amount signal is passed through the low signal selector 9 in order to reduce this. If this trend continues, the O concentration will not be able to maintain 7% and will fall, and when it attempts to exceed 6%, the high air volume signal to maintain 6% will be sent to the high signal selector. 10 and is output as a final operation signal.

By performing the above control operations, 0. 02 high operation and No. within the range that does not fall below 6%.

Compatible with upper limit control. Note that this 6% is the minimum value that maintains safe combustion, and has priority over NOx control.

[Brief explanation of drawings]

The drawing is a block diagram showing an embodiment of the invention. Explanation of main parts of the diagram 1 - NOx concentration set value 2 - NOx actual measured value 3 - NOx constant control device 4 - Normal OL concentration set value 5 - OL actual measured value 6.8 - 〇, constant control device 7 - Lower limit OL concentration setting value 9 - Low signal selector 10 - High signal selector 11 - Combustion air amount operation signal Patent applicant: Mitsubishi Heavy Industries, Ltd. N + Procedural amendment November 21, 1980 Commissioner of the Japan Patent Office Kazu Wakasugi Husband 1, Indication of the case, Patent Application No. 58-187747, 2, Name of the invention, Waste incinerator combustion control device 3, Relationship with the person making the amendment, Patent applicant address: 5, Marunojiju-chome, Chiyoda-ku, Tokyo 1 name
(620) Mitsubishi Heavy Industries, Ltd. 4, Agent Address: Mitsubishi Heavy Industries, Ltd., 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Name (6124) Patent Attorney Akatsuki Uesaka, 2 others 5, Sub-Agent

Claims (1)

[Claims] By using a signal selector to select the optimal signal from the operation signals from the normal OL control loop, lower limit O control loop, and No. 8 control loop, and adjusting the amount of combustion air, A garbage incinerator combustion control device characterized by being able to perform both control and NOx control.