JPS6311942B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for drying and baking paint attached to treated materials such as iron plates and wire rods, and in which solvent evaporation gas generated in the drying oven is led to an incinerator and incinerated. The purpose is to control the amount of air supplied to the incinerator so that it is suitable for preventing bad odors and for thermal efficiency.

The gas containing organic solvents evaporated from the drying furnace of the painting line for iron plates, wire rods, etc. is led to an incinerator, deodorized by incineration, and released into the atmosphere. The heat is returned to the drying oven as hot air to effectively utilize the heat. In such equipment, the amount of hot air is determined in relation to the amount of evaporation of the organic solvent and is determined to avoid the explosion range of the organic solvent, and the temperature of the hot air is determined in relation to the amount of hot air to be the amount necessary to evaporate the organic solvent, etc. Determined as the amount of heat. Also, increasing the amount of air supplied to the incinerator to increase the oxygen concentration inside the incinerator will improve the incineration and deodorization effect, but on the other hand, increasing the amount of supplied air will increase the amount of gas discharged to the outside of the system. Since the amount of make-up air is not uniformly controlled, it is not possible to save energy because the loss of energy increases. This was a situation where there was a large amount of energy dissipation or energy loss.

The present invention has been made in view of the above, and an object thereof is to provide a method for controlling odor concentration of an incinerator that can maximize energy saving while satisfying deodorizing conditions. Embodiments of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a drying oven, through which the treated material 2 coated with paint passes continuously. 3 is an incinerator (incinerator), and the solvent evaporation gas generated in the drying furnace 1 is guided to the incinerator through a pipe 4. 5 is an auxiliary combustion fuel pipe supplied to the incinerator 3, and 6 is an air supply pipe. A part of the combustion exhaust gas generated in the incinerator 3 is returned to the drying furnace 1 through the pipe 7, and the rest is discharged into the atmosphere from the chimney 9 through the heat exchanger 8. 10 is a blower that supplies air heated by the heat exchanger 8 to the supply pipe 6, and 11 is an air flow control valve. An oxygen concentration measuring device 12 is attached to the combustion exhaust gas outlet of the incinerator 3,
The output of the measuring device 12 is input to a setting device 13. The setting device 13 controls the air flow control valve 11 so that the residual oxygen concentration in the combustion exhaust gas measured by the measuring device 12 falls within about 2%.

FIG. 2 is a diagram showing the relationship between the residual oxygen concentration and the odor concentration. As can be seen from the diagram, the odor concentration is lowest when the residual oxygen concentration is around 2%. This is because when the residual oxygen concentration is lower than 2%, there is a lack of oxygen and combustion becomes incomplete, so the deodorizing effect is also reduced, and when the residual oxygen concentration is higher than 2%, the incineration temperature It is presumed that the odor concentration increases due to the decrease in the deodorizing effect due to the decrease in the odor concentration.

As described above with respect to the embodiments, the present invention has the following features:
An oxygen concentration measuring device is attached to the combustion exhaust gas outlet of the incinerator, and the amount of air supplied to the incinerator is adjusted so that the measured value is constant or within a certain range. Incineration can be optimally controlled at all times, preventing pollution due to odor emission, and at the same time contributing to the effective use of thermal energy.

[Brief explanation of the drawing]

FIG. 1 is a piping and control system diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing the relationship between residual oxygen concentration and odor concentration. DESCRIPTION OF SYMBOLS 1... Drying oven, 2... Processing material, 3... Incinerator, 6... Air supply pipe, 11... Air flow control valve, 12... Oxygen concentration measuring device.

Claims (1)

[Scope of Claims] 1. The treated material with the paint adhered to it is continuously passed through a drying oven, and the evaporated solvent gas generated in the drying oven is guided to an incinerator and air is replenished to remove the evaporated solvent gas. In a continuous paint drying and baking device that incinerates and returns part of the combustion exhaust gas into the drying oven, an oxygen concentration measuring device is attached to the combustion exhaust gas outlet of the incinerator to measure the residual oxygen concentration in the combustion exhaust gas. A method for controlling odor concentration in an incinerator, characterized in that the amount of air supplied to the incinerator is adjusted so that the amount of air is a constant value or within a certain range. 2. The incinerator odor concentration control method according to claim 1, wherein the residual oxygen concentration in the combustion exhaust gas is around 2%.