JP2005233594A - Incineration system for high moisture combustible waste, and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high moisture combustible waste incineration system superior in odor generation prevention, waste heat effective utilization, and drying capacity in incineration of high moisture combustible waste such as poultry manure. <P>SOLUTION: The incineration system is provided with a boiler 30 collecting waste heat of an incinerator 20 to generate steam S1, and a steam turbine 40 driven by the steam S1. A drier 10 is composed such that the waste Wa is dried by carrying out indirect heat exchange with steam S2 exhausted from the steam turbine 40, and it is composed such that at least one part of air A for combustion directly contacts and passes through the waste Wa before being supplied to the incinerator 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-moisture flammable waste incinerator excellent in terms of prevention of malodor generation, effective use of waste heat, and drying ability in incineration of high-moisture flammable waste such as chicken manure.

  Conventionally, for example, in an apparatus for drying and incinerating chicken manure, a high-temperature exhaust gas containing malodorous components is generated in the drying process, and the exhaust gas is burned, adsorbed or washed at a high or low temperature for the deodorization. Yes. In addition to drying and incineration of the chicken manure, not only hot water supply but also the generation of steam and the resulting power or power generation are performed for the purpose of effectively using waste heat.

  However, high-temperature combustion of malodorous exhaust gas is a new combustible material (fuel) for preparing flames and other ignition sources and for raising the temperature of the high-temperature exhaust gas in order to ignite and maintain the combustion of a large amount of exhaust gas. ), And low-temperature combustion of exhaust gas requires a low-temperature combustion device including an expensive, easy-to-degrade and clogged catalyst for promoting combustion of a large amount of exhaust gas at low temperature. is there.

  In addition, the adsorption (for example, Patent Document 1) requires cooling and temperature reduction (for example, less than 100 ° C.) of the large amount of exhaust gas, and the cooling and temperature reduction are performed by direct heat exchange and cleaning with cooling water. In this case, even if it causes the cooling water to evaporate, further increments of water vapor into the exhaust gas that already contains a large amount of water vapor are only allowed to saturate at the low temperature of the adsorption deodorization part. However, most of them have to rely on the temperature rise of the cooling water to the low temperature, and the temperature is raised by supplying a large amount of cooling water, which requires sewage treatment later, or by a separately provided chilled water tower, etc. There is a problem that a large burden of either cooling of the cooling water or concentration by evaporation of water that requires a large amount of heat is required. Although indirect heat exchange with cooling water is also conceivable, there are problems similar to the above as long as it depends on the temperature rise. ,

In view of the above, the inventor is investigating the drying of waste by indirect heating and the combustion of malodorous component gases in an incinerator to suppress the generation of malodorous component-containing exhaust gas. I learned that steam from waste heat recovery from incineration waste gas is used (for example, Patent Documents 2 and 3). However, for either purpose, the improvement of drying speed, downsizing of the dryer, and the steam partial pressure on the waste side, which is considered to have a serious impact on them, and for combustion before introduction into the incinerator There is no mention of the use of air.
JP 07-243626 A (

Claim 1

Thru

Claim 3

And FIGS. 2 to 4) JP 09-273707 A (

Claim 1

, Figures 1 and 3) JP-A-10-339416 (

Claim 1

Claim 2

And Figure 2)

  From the above, the present invention eliminates the disadvantages of the prior art described above, for example, in terms of prevention of malodor generation, effective use of waste heat, and drying capacity in incineration of high moisture flammable waste such as chicken manure. It is to provide an excellent high moisture flammable waste incinerator.

In order to achieve the above object, the high moisture flammable waste incinerator according to the invention of claim 1 is driven by the boiler 30 that recovers the waste heat of the incinerator 20 and generates the steam S1, and the steam S1. A steam turbine 40,
Waste dryers 10, 110, and 210 are configured such that the waste Wa is dried by indirect heat exchange with the steam S 2 discharged from the steam turbine 40 and / or the exhaust gas G 1 of the boiler 30. The dryers 10, 110, and 210 are configured to directly contact and pass through the waste Wa before at least a part of the combustion air A is supplied to the incinerator 20.

The invention of the high moisture flammable waste incinerator according to claim 2 includes a boiler 30 that recovers waste heat from the incinerator 20 and generates steam S1, and a steam turbine 40 driven by the steam S1. And
Air heaters 50, 150, 250 configured to indirectly exchange heat with at least part of the combustion air A with steam S2 discharged from the steam turbine 40 and / or exhaust gas G1 of the boiler 30, and the air Prior to the combustion air A1 heated by the heaters 50, 150, 250 being supplied to the incinerator 20, a dryer 310 configured to directly exchange heat with the waste Wa and to dry the waste Wa. It has.

  According to the invention of claim 1, since the dryers 10, 110, and 210 are of the indirect heat exchange type, the exhaust gas containing malodorous components does not mix with the steam S2 or the exhaust gas G1 of the incinerator 20 that is a heating medium. Since it consists mainly of water vapor from the water in the waste Wa and the combustion air A, it can be introduced as it is into the incinerator 20 without any trouble, and the malodorous component is introduced in the incinerator 20 introduced. Since it burns and is not brominated, it can be released into the atmosphere as it is.

  In addition, the surroundings of the waste Wa on the heat receiving side are in direct contact with it, and water vapor generated by at least a part of the passing combustion air A is taken out of the system (incinerator 20), thereby reducing the water vapor partial pressure. Therefore, even if the temperature of the waste Wa is not increased, the pressure difference with the water vapor pressure on the surface of the waste Wa, which is one of the drying driving force factors, increases and the combustion air A is not introduced. The drying rate is high compared to Therefore, if the conditions on the heating side are the same, the dryers 10, 110, and 210 may be small, or the degree of drying increases, the burden of moisture removal in the incinerator 20 is reduced, and the supply to the boiler 30 is reduced. The amount of heat increases and the output of the steam turbine 40 increases.

  When the heating medium is steam S2, the output of the steam turbine 40 is slightly reduced by that amount, but the burden on the condenser is reduced. Further, when the heating medium is the boiler exhaust gas G1 and the output of the steam turbine 40 is maintained as it is, the temperature of the boiler exhaust gas G1 directed to the drying of the waste Wa becomes lower, and compared with the condensation heat transfer of steam. In addition, since the heat transfer coefficient on the heating side is considerably low, the required heat transfer area of the dryer 110 is large, but since it is normal pressure, the structure is simple and there are few restrictions on strength, sealing, and the like. In addition, when both steam S2 and boiler exhaust gas G1 are used together as a heating medium of the dryer 210, both advantages are utilized.

  According to the invention of claim 2, the structure of the dryer 310 is remarkably simplified, and the heating medium in direct contact with the waste Wa is at least the combustion air A1 heated by the air heaters 50, 150, 250. In part, water vapor is mainly added from the water in the waste Wa, and can be introduced as it is into the incinerator 20 without any trouble. Moreover, malodorous components contained therein are combusted in the introduced incinerator 20. Because it is not brominated, it can be released into the atmosphere as it is.

  When the air heater 50 (heating medium is steam S2), the output of the steam turbine 40 is slightly reduced, but the burden on the condenser is reduced. Further, when the air heater 150 (the heating medium is the boiler exhaust gas G1) and the output of the steam turbine 40 is maintained as it is, the temperature of the boiler exhaust gas G1 directed to the heating of the combustion air A becomes low, Compared to steam condensation heat transfer, the heat transfer coefficient on the heating side is considerably low, so the required heat transfer area of the air heater 50 is large, but because of normal pressure, the structure is simple, There are few restrictions such as seals. On the other hand, when both steam S2 and boiler exhaust gas G1 are used together as the heating medium of the air heater 250, both are effectively utilized and the advantages of both are utilized.

BEST MODE FOR CARRYING OUT THE INVENTION

  The best mode for carrying out the high-moisture combustible waste incinerator according to the present invention will be described with reference to FIG. 1. First, the apparatus configuration will be described. Reference numeral 10 denotes an indirect heat exchange type high-moisture combustible waste Wa ( The dryer 20 is also abbreviated as “waste” including the dried product, and 20 is an incinerator for incinerating the waste Wa dried by the dryer 10, and the waste heat is recovered to generate steam S1. A boiler 30 is attached. A steam accumulator 31 stores the steam S1 and stabilizes its pressure and supply amount, 40 is a steam turbine driven by the steam S1, and 41 is a generator driven by the steam turbine 40. -A fan etc. may be sufficient. A condenser 42 is used in the dryer 10 to completely return the steam S2 partially condensed to water.

  In addition, Cy is a cyclone that separates dust contained in the exhaust gas G1 from the boiler 30 and the exhaust gas G2 from the dryer 10, F is a fan that attracts the exhaust gases G1, G2, etc., and P is condensed in the condenser 42 The pump pressurizes the water W and supplies it to the boiler 30. In addition, as the dryer 10, the waste type Wa is configured to be sent to the other end by an agitation / transport device provided inside, a rotary type in which the entire casing is rotated, and the incinerator. 20 may be any of a stationary type with an inclined grate, a cylindrical rotary furnace, or the like.

The action will be described. At one end of the dryer 10, for example, 1 t / h of chicken manure having a moisture content of 50% (low heating value 3,900 Kcal / kg) and about 250 ° C. and 4,000 Nm ³ / h of combustion air A are all present. On the other hand, in parallel to the space separating the waste Wa and the heat transfer surface, the steam turbine 40 worked, and the temperature and pressure were reduced to 3 kg / cm ² and 2.2 t / h. Steam S2 is introduced. While the waste Wa and the combustion air A pass through the dryer 10, they are separated from the steam S2 by the heat transfer surface and do not mix, but are in close thermal contact with each other through the heat transfer surface, It is discharged from the other end while performing effective heat exchange. Meanwhile, the steam S2 condenses and the waste Wa is heated and dried.

Further, the waste Wa having a moisture content of 25% is dried by gravity or an appropriate transport device (not shown), and the combustion air to which water vapor of about 41 Nm ³ / h is added is the fan F, the cyclone Cy. And then sent to one end of the incinerator 20. Among them, the waste Wa burns with the support of oxygen contained in the exhaust gas G2 mainly composed of air of the dryer 10 while moving toward the other end in the incinerator 20, and becomes ash As. Discharged. At that time, the malodorous component contained in the exhaust gas G2 also burns and is not brominated. The combustion gas of about 5,700 Nm ³ / h generated by the combustion of the waste Wa is sent to the attached boiler 30, gives the heat it has to the water W, and cools itself by 18.5 Kg / cm steam. S1 is generated, the temperature is lowered, and the boiler exhaust gas G1 is discharged to the atmosphere through the fan F and the cyclone Cy.

  The steam S1 generated in the boiler 30 is temporarily stored in the steam accumulator 31 and then sent to the steam turbine 40 to generate power and become low-temperature and low-pressure steam S2, which is sent to the dryer 10 as described above. It is done. Further, the steam containing the condensed water used in the dryer 10 is sent to the condenser 42, completely returned to the water W, pressurized by the pump P, and returned to the boiler 30 again. In addition, the motive power generated by the steam turbine 40 is converted into electric power by the generator 41 or is not shown, but is used as it is for driving a fan or a pump.

  Explaining the effect, the gas G2 discharged from the dryer 10 is mainly composed of water vapor and air A from the water in the waste Wa, and can be directly introduced into the incinerator 20 without any trouble. In addition, the malodorous component contained therein is burned in the introduced incinerator 20, is not brominated, and can be released into the atmosphere as it is. Steam S2, which is a heating medium, is returned to water completely by the condenser 42 without being mixed with the exhaust gas G2 and reused as water supply to the boiler 30 because the dryer 10 is an indirect heat exchange type. .

  In addition, the periphery of the waste Wa on the heat receiving side is in direct contact with it, and the water vapor generated by the passing air A is taken out of the system (incinerator 20), thereby reducing the partial pressure of the water vapor. Even if the temperature of Wa is not increased, the pressure difference with the water vapor pressure on the surface of waste Wa, which is one of the driving factors of drying, is increased, and the drying speed is compared with the case where combustion air A is not introduced. Is expensive. Therefore, if the conditions on the heating side are the same, the dryer 10 may be small, or the degree of drying increases, the burden of moisture removal in the incinerator 20 is reduced, and the amount of heat supplied to the boiler 30 increases. The output of the steam turbine 40 increases.

  An embodiment different from the above will be described with reference to FIG. 2. The waste Wa dryer 110 is configured such that the exhaust gas G1 of the boiler 30 is used as the heating medium instead of the exhaust steam S2 of the steam turbine 40. Except for the above, the other configurations are substantially the same as those described above. Note that the steam S2 condenses in the above-described dryer 10, whereas the exhaust gas G1 does not change in phase in the dryer 110, and the temperature is reduced. For this reason, the structure is slightly different from the above-described ones due to differences in heat transfer properties and the like, but there is no difference in the basic principle, and the operational effects are substantially the same as those described above.

  If the difference is raised, when the heating medium is steam S2, the output of the steam turbine 40 is slightly reduced and the burden on the condenser is reduced, whereas when the heating medium is the boiler exhaust gas G1, If the output of the steam turbine 40 is maintained as it is, the temperature of the boiler exhaust gas G1 directed to drying the waste Wa is low, and the heat transfer coefficient on the heating side is considerably higher than the condensation heat transfer of steam. Since it is low, the required heat transfer area of the dryer 110 becomes large. However, since it is a normal pressure, there is an advantage that the structure is simple and there are few restrictions such as strength and seal.

  Further, FIG. 3 will be described with respect to the compromise of the above two aspects. That is, in the dryer 210, the heating medium supply zone is divided into two so that the waste gas Wa is supplied with the exhaust gas G1 of the boiler 30 on the upstream side and the exhaust steam S2 of the steam turbine 40 on the downstream side. ing. The rest of the configuration other than that is the same as that of the above two embodiments, so there is no difference in the basic principle, and the operational effects are also substantially the same. ,

  When the difference is raised, (1) In the zone where the water content of the waste Wa is high and easy to dry, the exhaust gas G1 of the boiler 30 having low heat conductivity is used, and the water content of the waste Wa is low and difficult to dry. Then, by using steam S2 with high heat conductivity, the drying rate of the waste Wa in each zone is made as high as possible, so that the heat transfer area of the dryer 210 is relatively small, (2) The waste heat of the exhaust gas G1 of the boiler 30, which can be discarded as it is into the atmosphere, is effectively used, and the use of the steam S2 is saved correspondingly, and the reduction in the output of the steam turbine 40 is suppressed. It is.

  Next, another best mode for carrying out the high moisture flammable waste incinerator according to the present invention will be described with reference to FIG. When a device different from the above-described embodiment is lifted, 50 is an indirect heat exchange type air heater by the exhaust gas G1 of the boiler 30, and 310 is a direct heat exchange type by the combustion air A1 heated by the air heater 50. It is a dryer. Since the exhaust steam S2 of the steam turbine 40 is not used for drying the waste Wa, the energy of the steam S1 is converted to maximum power except for hot water supply and other heating not shown.

  To explain the operation, an indirect heat exchange type air heater 50 is separately required, but it is based on the existing technology and has no practical problem, so that the sensible heat of the exhaust gas G1 of the boiler 30 is used for combustion. Combustion air A1 that is effectively transmitted to and heated by at least a part of the air A is introduced as a heating medium into the direct heat exchange dryer 310, which is also based on existing technology and has no practical problems, Direct contact with waste Wa and effectively dry it.

  In addition, the heating medium in direct contact with the waste Wa is the air A1 heated by the air heater 50, and only the water vapor from the waste Wa is mainly added to the dryer 310 by the dryer 310. It can be introduced into the incinerator 20 as air, and it burns in the incinerator 20 into which malodorous components contained therein are introduced, is not brominated, and is released into the atmosphere. As described above, the dryer 310 is based on the existing technology and is a direct heat exchange type, so that the structure is remarkably simple, small, and inexpensive.

  Next, another embodiment will be described with reference to FIG. 5, except that the indirect heat exchange type air heater 150 with the steam S <b> 2 is used in place of the air heater 50 described above, the other configurations are the same as those described above. It is almost the same as the thing. According to this, since the heat transfer of the heating medium of the air heater 150 is due to the condensation of steam, the heat transfer property is remarkably excellent, and the heat transfer area is reduced. However, there is a problem that the output of the steam turbine 40 is reduced correspondingly, the temperature level of the steam S2 is relatively low, and high-temperature air cannot be obtained.

  The third aspect will be described with reference to FIG. 6. The air heater 250 is configured so that the exhaust gas G1 of the boiler 30 and the exhaust steam S2 of the steam turbine 40 are used in combination as the heating medium. According to this, the first low temperature region where the temperature of the air is still low is configured to be heated by steam S2, and the second high temperature region is heated by the boiler exhaust gas G1, and compared with that shown in FIG. However, the above-mentioned problem that the output of the steam turbine 40 is reduced and high-temperature air cannot be obtained is considerably improved.

It is a systematic diagram which shows the best form of the apparatus of this invention. It is a systematic diagram which shows another embodiment of FIG. It is a systematic diagram which shows the 3rd embodiment of FIG. It is a systematic diagram which shows the other example of the best form of the apparatus of this invention. It is a systematic diagram which shows another embodiment of FIG. It is a systematic diagram which shows the 3rd embodiment of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Dryer 110 Dryer 210 Dryer 310 Dryer 20 Incinerator 30 Boiler 31 Steam accumulator 40 Steam turbine 41 Generator 42 Condenser 50 Air heater 150 Air heater 250 Air heater A Air A1 Heated air As Ash Cy Cyclone F Fan G1 Exhaust gas G2 Exhaust gas P Pump S1 Steam S2 Steam W Water Wa Waste

Claims (2)

High moisture flammable waste comprising a boiler (30) that recovers waste heat from an incinerator (20) and generates steam (S1), and a steam turbine (40) driven by the steam (S1) Incinerator of
A dryer configured to dry waste (Wa) by indirect heat exchange with steam (S2) discharged from the steam turbine (40) and / or exhaust gas (G1) of the boiler (30). (10, 110, 210), and the dryer (10, 110, 210) includes at least a part of the combustion air (A) before being supplied to the incinerator (20). An incinerator for high moisture flammable waste, characterized in that it is configured to directly contact and pass through waste (Wa). High moisture flammable waste comprising a boiler (30) that recovers waste heat from an incinerator (20) and generates steam (S1), and a steam turbine (40) driven by the steam (S1) Incinerator of
Air heating configured so that at least part of the combustion air (A) indirectly exchanges heat with the steam (S2) discharged from the steam turbine (40) and / or the exhaust gas (G1) of the boiler (30). Prior to supplying the incinerator (20) with the air (A1) heated by the vessel (50, 150, 250) and the air heater (50, 150, 250), the waste (Wa) A high-moisture flammable waste incinerator comprising a dryer (310) configured to directly heat-exchange and dry the waste (Wa).

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