JPS58168807A - Incinerator for sludge - Google Patents

Abstract

PURPOSE:To prevent wearing of an incinerator and a dryer due to excessive feeding of auxiliary fuel, as well as to save the consumption of auxiliary fuel, by automatically introducting the auxiliary fuel so that its introducing rate is suitable to the amount of sludge. CONSTITUTION:A level gauge 10 is provided to a dry sludge tank 4. When the level gauge 10 for dry sludge in the tank 4 falls down lower than a predetermined level, the feeding speed of auxiliary fuel from a hopper 6 is increased by a controller 11. When the level is heightened, the introducing speed is slowed down. On the other hand, a temperature detector 12 is provided to the passage of exhaust gas, discharged from a dryer 1. When the temperature of the exhaust gas becomes lower than a predetermined temperature, the blast rate to an incinerator 2 is increased by increasing the opening of a flow-rate controller 9 by a controller 13, while the blast rate is decreased when the temperature of exhaust gas is high. With such an arrangement, wasteful consumption of auxuliary fuel can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for pre-drying and incinerating sludge that cannot self-combust due to its high moisture content and low calorific value, and in particular for dewatered sludge. The method is characterized in that the exhaust gas from the dewatered sludge is used for pre-drying, and the amount of heat insufficient for pre-drying is compensated for by adding granular auxiliary fuel to the dehydrated sludge. It is something to do.

Normally, organic sludge is dehydrated, pre-dried, and then incinerated for disposal. In this case, the amount of heat required to pre-dry the dehydrated sludge uses the heat generated when the pre-dried sludge is incinerated, but since dehydrated sludge contains 70 to 90% water. Depending on the amount of heat generated by the recycled paper components in the sludge, it may not be possible to dry the dehydrated sludge to a combustible state. In such cases, a method of adding combustible powder such as wood powder or powdered charcoal to the sludge as an auxiliary fuel is sometimes adopted, but conventionally,
It was not possible to determine the appropriate amount of auxiliary fuel to be added, that is, the minimum amount sufficient to dry the dehydrated sludge.
Measures were taken such as adding extra auxiliary fuel and cooling the excess heat by spraying water.

The present invention has been made in view of the above points, and includes:
Auxiliary fuel is automatically added to the sludge in an appropriate amount, reducing the amount of auxiliary fuel consumed through kneading, and reducing wear and tear on the burner and dryer due to excessive addition of auxiliary fuel. It is something.

Hereinafter, the present invention will be specifically explained based on the drawings.

In the figure, symbol l is a dryer, and symbol 2 is an incinerator. Dryer 1 pre-dries dehydrated sludge to a combustible state. Incinerator 2 incinerates the dried sludge, and dryer l It serves as a source of hot air for the air. The dryer 1 is no different from a normal dryer of this type, and, for example, a horizontal rotary drum dryer is used. 3 is a sludge supply hopper for supplying dehydrated sludge to the dryer 1. It is. This supply hole <3 is formed so as to be able to supply dehydrated sludge to the dryer l at a uniform rate; The dehydrated sludge is supplied at a speed corresponding to the rotational speed of the screw.The dehydrated sludge is brought into contact with the hot air blown from the incinerator 2 in the dryer IIl. The sludge is dried to a predetermined moisture content, discharged outside the premises, and put into a dry sludge tank 4. On the other hand, the highly humid exhaust gas discharged outside the machine is discharged into the atmosphere through exhaust gas treatment equipment. Reference numeral 6 is an addition hopper for adding auxiliary fuel to the sludge.Although not shown in the figure, it is formed in such a way that the amount of addition can be automatically adjusted. Although the configuration is shown in which the auxiliary fuel is added to the dryer Ill along with the dehydrated sludge, there is no problem in constructing the pigeon coop so that the auxiliary fuel is added to the dried sludge discharged from the dryer Ill.
The reason why the addition hopper 6 is configured as shown in the figure is that the auxiliary fuel is used as a drying aid for the dehydrated sludge to enhance the drying effect of the sludge. That is, when the dehydrated sludge is viscous and easily forms into a Jll shape in the dryer 411, it is necessary to loosen it. In such cases, by mixing granular auxiliary fuel with dehydrated sludge, it is possible to obtain a dispersion effect on the sludge in the dryer and dry it. Since the powdered auxiliary fuel is trapped inside and discharged from the dryer, the combustion in the furnace is uniform, which resulted in 8 points.

The dried sludge containing the 9 auxiliary fuel charged into the dry sludge tank 4 is transferred to the supply hopper 7 and then fed into the incinerator 2.
The incinerator 2 is different from a normal granular material incinerator of this type.

- As an example a fluidized bed incinerator is used. Air blower 7 an 8
The amount of combustion air supplied to the incinerator 2 from
High-temperature hot air is introduced into the drying process II.
It is composed of K. The incineration capacity of the incinerator 20 is such that it can generate the amount of heat necessary for drying the drying process, at least not less than 0.
In addition, when this device is operated in a steady state, (1) dehydrated sludge is fed into the dryer IK at a constant speed),
The auxiliary fuel is added to the sludge (at a constant rate) to achieve the minimum mixing ratio required.◎ By the way, this device is capable of adding the auxiliary fuel to the dehydrated sludge in terms of the addition rate. The sludge is lined with side ropes to keep the appropriate amount of sludge. That is, the dry sludge tank 4 is equipped with a level gauge 10, and when the dry sludge in the tank 4 drops below a predetermined level, the side sound device U speeds up the addition speed of auxiliary fuel from the addition hopper 6. As the level increases, the addition rate is slowed down. In addition, temperature detection *U is installed on the exhaust path of the exhaust gas discharged from the dryer l, and the exhaust gas otm
When t falls below a predetermined temperature, the flow rate adjustment device @9t) increases the amount of air blown to the incinerator 2 by increasing the abdominal opening, and decreases the amount of air blown when the temperature of the exhaust gas rises. Here, we replaced the moisture detection after drying with the temperature detection of the exhaust gas, but if the temperature of the dried sludge or the moisture can be measured on a skewer, there is no need to insist on detecting the exhaust gas temperature. There is no objection, and if the moisture content of the dried sludge on tatami mats is high, the amount of air blown to the incinerator should be increased, and if the amount of air blown to the incinerator is low, it should be reduced.
The incinerator is equipped with a temperature detector 14, and when the temperature inside the furnace falls below a predetermined temperature, the side cable device 11jl
Increase the amount of dried sludge input into the supply hopper 7,
When the temperature rises above a predetermined temperature, the input amount is reduced, and the temperature inside the furnace is kept constant regardless of the change in the amount of air fed into the incinerator 2, so that hot air at a constant temperature is sent to the dryer S. In addition, a 4-level gauge 1 is provided in the supply hollow puff, and 01 in the hopper is configured.
When the 1L dried sludge becomes less than a certain amount, the dried sludge in the dry sludge tank 4 is sent to the supply hose buff. First, it is assumed that the device is operating in a steady state. In this state, it is assumed that dehydrated sludge, which has a higher water content than normal, is fed into the dryer l from the sludge supply hopper 3. Then, the temperature of the exhaust gas decreases by the amount of water in the sludge 011 (C)e.

The temperature detector U detects the temperature [0 drop, and the side cable device 11
3 is activated and the flow rate adjustment device msc+1 is increased by 1 to increase the amount of air O fed into the incinerator 2. Then, the temperature inside the furnace decreases accordingly, so the tube temperature detector 1
4, the side cable system @Ut is activated to increase the amount of dried sludge O input to the incinerator 2, thereby increasing the temperature inside the furnace.As a result, the amount of heat supplied to the dryer 1 is increased. To increase.

On the other hand, compared to the dryer IK, there is dry dirt! When the O input amount increases, the dried sludge O level in the dry sludge mentor 4 decreases by that amount, so the side cable device lu operates to increase the amount of auxiliary fuel added. II.

On the other hand, when the dehydrated sludge 0** water content is low, the amount of air fed into the incinerator 2 decreases and the input speed of dried sludge slows down, so the level of dried sludge in the dried sludge tank 4 increases, Therefore, the amount of auxiliary fuel added decreases.

In this way, the amount of auxiliary fuel added increases or decreases as the dehydrated sludge O gold and water content changes, and auxiliary fuel suitable for incineration is mixed with S<~X pollution, and waste of auxiliary fuel is incinerated. is nothing (0 that is 0 that fades)

[Brief explanation of the drawing]

The figure is a system diagram showing one embodiment of the present invention.

Claims (1)

[Claims] Equipped with an incinerator and a dryer, the dryer is charged with dehydrated sludge and auxiliary fuel to pre-dry it, the dried material is incinerated, and the resulting combustion gas is used as a heat source for drying the dryer. In a sludge incinerator, a control device detects the temperature of exhaust gas discharged from the dryer and adjusts the amount of air fed into the incinerator, and a control device detects the temperature inside the incinerator and supplies dried sludge to the incinerator. Sludge comprising: a control device that adjusts the amount of auxiliary fuel to control the furnace temperature to a predetermined temperature; and a control device that detects the level of dried sludge in a dry sludge tank and controls the amount of auxiliary fuel added. Incinerator.