JPS59125315A - Method and device for recovery of potential heat of material drained from fluidized-bed combustion furnace - Google Patents

Abstract

PURPOSE:To achieve energy saving and to enable a blower, which is used only during the starting and is brought to a stop after the starting, to be normally operated even after the starting, by a method wherein the potential heat of a drained material is recovered as the air for combustion for use in a fluidized- bed combustion furnace. CONSTITUTION:A booster blower 15 is provided, or a controller 16 for the number of revolutions is provided for a main blower 12, and even in case a blower for the starting is not provided, the controller 16 for the number of revolutions or the booster blower 15 is employed during the starting, the air for combustion is fed to a fluidized-bed combustion furnace 6 from the main blower 12 through an air duct 13, an air preheater 14, an air duct 3, an air heating furnace 4, and an air duct 5. During normal operation, a drained material is fed to a heat exchange vessel 8, and meanwhile, the air for combustion is fed to the heat exchange vessel 8 from the main blower through an air duct 9 to heat-exchange it with the drained material, the air for combustion, heat-exchange through an air duct 10, is fed to the fluidized-bed combustion furnace 6, and a part thereof is supplied to the fluidized-bed combustion furnace 6 through a bypass air duct 17.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a fluidized bed combustion furnace to burn and polish a pulp waste liquid containing a powder component and a fluidized medium such as iron oxide, and convert the in-furnace generated material into IM, @lJ bed combustion bed. When extracting the alkaline liquid from the furnace, a heat exchanger tank is provided to recover the heat retained in the extracted material produced in the furnace (hereinafter referred to as extracted material) as combustion air for the fluidized bed combustion furnace. Part 1 relates to a device for recovering heat retained in the extracted material.

Conventionally, the extracted material was cooled and extracted using cooling water or air, and the retained heat was not recovered from the extracted material using combustion air.

” In view of the above, the present invention provides for the extraction of material at 800 to 100
The retained carbon is recovered as combustion air for the fluidized bed combustion furnace, achieving energy savings and being used only during startup.
The startup ventilation fan, which had been stopped after startup, will not be used continuously even after startup.

If a starter ventilator or booster ventilator is not installed, a king ventilator or other ventilator may be used.

The first aspect of the present invention is a method in which a pulp waste liquid and a fluidized reaction medium are subjected to a combustion reaction in a fluidized bed combustion furnace, and the generated reactants in the furnace are extracted. A fluidized bed combustion furnace that exchanges heat with air and supplies the combustion air to the fluidized bed combustion furnace to recover the heat retained in the extracted material, cool the extracted material, and take it out from the heat exchanger tank. The second is a heat recovery method for materials, and the second is a method that is equipped with a starting draft fan, a starting hot blast furnace, or combustion equipment, and is further equipped with a starting draft fan or Goosef draft fan and a rotation speed control device, etc. or fluidized bed combustion furnace equipment [
Equipped with a heat exchanger tank, the heat exchanger tank is connected to a starting draft fan or live draft fan, and the heat exchanger tank and fluidized bed combustion P7 are each connected by air passages, and after the fluidized bed combustion furnace is started, the combustion air is and the extracted material led to the heat exchanger tank from the extraction pipe provided in the fluidized bed combustion furnace, and the heat-exchanged combustion air is supplied as combustion air to the fluidized bed combustion furnace. The present invention provides a retained heat recovery device for extracted material from a fluidized bed combustion furnace.

In general, pulp waste liquid is a highly water-containing fuel and has a low calorific value (on an absolute dry high level basis) of 3000 to 3500 K (:(Ll/=9), which results in better combustion when the heat retained in the combustion air is increased.

When a causticizing reactant produced by a combustion reaction of pulp waste liquid and a reaction medium in a fluidized bed combustion furnace is supplied to a hydrolysis process, the temperature of the extracted material is SOO to 1000°C.

When the alkali solution and the reaction medium are separated and recovered from the extracted material, the leakage rate of dissolved M is about 150"C: or less.

Therefore, in the case of an unexploded JU, the extracted material is preserved, and as much heat as possible is recovered using the combustion air of the fluidized bed combustion furnace, and the extracted material is also cooled.

In addition, in a fluidized bed combustion furnace, in order to raise the temperature of the fluidized medium to a predetermined temperature of 300 to 800' (J), a hot blast furnace or combustion equipment is installed, and hot air of 400 to 900''C is used for fluidized bed combustion. It is preferable to supply the furnace to the furnace and shorten the startup time as much as possible. In this case, the ventilation pressure loss for startup will be greater than during constant operation (300 to 700 ram).
q5・Enter ItK is dealt with by providing a rotation control device light, etc. to the starting ventilator, Goosef ventilator, or king ventilator.

However, it is common for these ventilators or equipment to be stopped after the start-up of the moving bed combustion/decommissioning system and not to be used during regular operation.

The present invention makes it possible to use the idle ventilation fan or devices even during continuous operation, thereby increasing the discharge pressure of the ventilation fan or installing a new ventilation fan. It's not necessary.

Next, we will explain ``misfire'' using the drawings.

Figure 1 is a flowchart of a conventional fluidized bed combustion furnace device, in which the startup fan (1) is operated only at startup, and the combustion air is heated in the hot blast furnace (4), and the air is heated through the air duct (2). f3) and (5) to the fluidized bed combustion furnace (6), and during regular operation, the combustion air is passed through the air preheater (14) from the king fan (12) to the air passage (13), (15) then fluidized bed combustion furnace (6)
through the extraction pipe (7) from the fluidized bed combustion furnace,
It was supplied to the dissolution tank 0).

Fig. 2 is a flow sheet of an embodiment of the present invention that is equipped with a starting ventilator that is always used, and Fig. 2 is another embodiment of the present invention in which a rotation control device is provided for a Toosuf ventilator and a king ventilator. This is a flow sheet of the process.

In Fig. 1, at startup, the startup fan fl) is used to generate hot air in the hot blast furnace (4) through the air ducts i2) and [3), and the combustion air is supplied to the fluidized combustion furnace (6). do.

When the system starts to operate normally, it conventionally operates as shown in Figure 1 above, but in the case of a misfire, the fluidized combustion Ff
The material extracted from 61 is passed through the extraction pipe (7) to the newly installed heat exchanger tank (s).The VC is guided, and the active ventilation fan m is constantly operated to supply combustion air from the startup ventilation fan to the wind temperature. (2) and the unexploded EII [thus, the newly installed air duct (1)), K is introduced into the heat exchanger tank (8), and heat exchanged with the extracted material, and the fluid pressure is passed through the air duct (10). It is supplied as heated combustion air to the combustion furnace (6).

Therefore, in the case of Fig. 2, the amount of ventilation from the starting ventilation fan (1) is used as most or part of the combustion air.
This has the advantage of reducing the amount of ventilation from the main fan during constant operation.

Figure 3 shows whether the booster fan (15) is equipped or
If the E ventilation fan (12) is equipped with a rotation speed control device (16) and a startup ventilation fan is not provided, the rotation speed control device @
Use (161 or Boo, Suffu Ventilation!!i 115) 1. From the main ventilation fan (12), air duct [+ + (), air preheater (14), air duct (3), hot air stove (4), air duct (5
), the combustion air is supplied to the fluidized combustion furnace [(il K), but in the case of continuous operation, the extracted material is guided to the heat exchanger tank (8) as in the case of Fig. 2, and the Rikio ventilation Combustion air from the machine is led through the air duct (9) to a heat exchanger tank (8), where it is exchanged with the extracted material.The combustion air that has been heat exchanged through the air duct (10) is used for fluidized bed combustion. Furnace +6 [supplied. A portion is supplied to the fluidized bed combustion furnace (6) by /kuinokusu wind duct (lη).

Incidentally, in the case where the starting ventilator (1) or the booster ventilator (15) is not installed, the uninvented invention can be similarly implemented using only the main ventilator (12) or other ventilators.

The effects of [non-explosion] are summarized as follows.

(r) Whether equipped with a starting draft fan or not, provide an air passage leading to the main draft fan and the heat exchanger tank;
800 by exchanging combustion air with the extracted material.
It becomes possible to recover the heat retained in the extracted material at ~1000°C, which has a large energy saving effect and also allows cooling of the extracted material.

(11) Furthermore, it is possible to reduce the capacity of the main ventilator by constantly operating the starter ventilator or booster ventilator, etc., without having to take a break.

[Brief explanation of the drawing]

Figure 1 is a flow sheet of a fluidized bed combustion furnace device by Xumai, and Figure 2 is a flow sheet of an example of a fluidized bed combustion furnace device equipped with a starting ventilator used in Honbatsu. FIG. 3 shows a flow sheet of another embodiment of a fluidized bed combustion furnace using a non-explosion jK equipped with a rotational speed control device in the Gouster ventilator or the main ventilator. 1. Starting ventilation fan 4° ~ Furnace 6, Combustion furnace 7° Extraction pipe 8, Heat exchanger tank 12° Main ventilation 14° Air preheater 15° Booster ventilation 1G, Rotation speed control device #'- 'j rrl Applicant Kawasaki Heavy Industries, Ltd. Figure 3 Figure 1 Figure 2 Continued from page 1 0 Inventor Yukichi Takeshita 4-1 Shimaya-cho, Konohana-ku, Osaka - Example -

Claims (1)

[Claims] 1. Bulge 1. Light liquid? In this method, the retained heat of the extracted in-furnace reactant (hereinafter referred to as extracted material) is transferred to a heat exchanger tank by causing a combustion reaction with a perturbation reaction medium in a flowing O1 bed combustion furnace and extracting the generated in-furnace reactant. The heat is recovered and the combustion air is supplied to the fluidized bed combustion furnace, and the extracted material is cooled and recovered from the heat exchanger tank. A method for recovering heat retained in the extracted material from fluidized bed combustion, which is characterized by: 2. Equipped with a king ventilation fan, a hot air flow generator for startup, or combustion equipment,
In addition, a starting ventilator, a goosef ventilator, or a rotation speed control fan.
Equipped with or without equipment etc. and are connected by a wind duct, and after starting the fluidized bed combustion furnace,
Combustion air is heat exchanged with the extracted material led from the extraction pipe provided in the fluidized bed combustion furnace to the heat exchanger tank, and the heat exchanged combustion air is used as the combustion air of the fluidized bed combustion furnace. A heat recovery device for the extracted material from the fluidized bed combustion furnace.