JP6552762B1 - Combined plant and excess heat recovery method for combined plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover surplus heat of exhaust gas containing purified carbon dioxide supplied from an exhaust gas purification facility to a plant cultivation facility and use this heat in the power generation facility to increase energy efficiency, and to increase the running cost of the power generation facility Reduce the amount of SOLUTION: A boiler 5 that recovers heat from an exhaust gas G containing carbon dioxide generated by burning fuel and generates steam S; a economizer 6 that further recovers heat from the exhaust gas G; The steam turbine 11, the generator 12 that generates power by driving the steam turbine 11, the condenser 13 that converts the exhaust steam S ′ discharged from the steam turbine 11 into the condensate W, and the condensate W from the condenser 13 is removed. A power generation facility 1 including at least a deaerator 14 that performs air treatment, an exhaust gas duct 31 that flows exhaust gas G generated in the power generation facility 1 to the plant cultivation facility 2, and an exhaust gas purification processing unit that purifies the exhaust gas G flowing in the exhaust gas duct 31 32, an exhaust gas purification facility 3 having at least one boiler water used in the power generation facility 1 between the power generation facility 1 and the exhaust gas purification facility 3. And the exhaust gas G, which is purified by the exhaust gas purification processing unit 32 and heated at a higher temperature than the boiler water, heats the boiler water by the excess heat of the exhaust gas, and this heated boiler water Is provided with a surplus heat recovery device 4 for returning the power to the power generation facility 1. [Selection] Figure 3

Description

  The present invention relates to a power generation facility that generates electricity by burning fuel such as biomass, fossil fuel, waste and the like, and an exhaust gas purification facility that supplies exhaust gas containing carbon dioxide obtained by purifying exhaust gas generated by the power generation facility to plant cultivation facilities In particular, there are power generation facilities that use biomass such as woody biomass, plant biomass, and livestock biomass as fuel, and exhaust gas generated in the power generation facility. At least a part of it is purified to remove substances (for example, sulfur oxides, nitrogen oxides, carbon monoxide, ethylene, etc.) that impair plant growth from the exhaust gas, and the exhaust gas containing carbon dioxide to plant cultivation facilities The present invention relates to a combined plant including an exhaust gas purification facility to be supplied and a method of recovering excess heat from the combined plant.

  Generally, in plant cultivation facilities such as greenhouses and plant factories that grow plants such as agricultural crops and horticultural plants, when the outside temperature is low as in winter or at night, biomass, heavy oil, kerosene, etc. are used for temperature control. The hot water and the warm air obtained by burning the fuel are supplied to the plant cultivation facility to keep the temperature in the plant cultivation facility at a predetermined temperature.

  In addition, in plant cultivation facilities, in order to promote growth, yield and quality of plants such as agricultural crops and horticultural plants, plant exhaust gas containing carbon dioxide generated by combustion of fuel such as biomass, heavy oil and kerosene It is supplied to the facility to promote photosynthesis of plants.

  By the way, in plant cultivation facilities, substances that impede plant growth, such as sulfur oxides, nitrogen oxides, carbon monoxide, and ethylene, in exhaust gas generated by combustion of fuels such as biomass, heavy oil, and kerosene. Therefore, for example, as shown in Patent Documents 1 to 5, substances that impede plant growth are removed from exhaust gas, and exhaust gas containing carbon dioxide is supplied to plant cultivation facilities. ing.

  The Patent Document 1 includes a combustion furnace that burns biomass, a heat exchanger that obtains heat by heat exchange between the exhaust gas discharged from the combustion furnace and supplies heat to the plant production facility, and the exhaust gas. A sulfur oxide removing device for removing sulfur oxide, a dust collecting device for collecting soot and dust contained in exhaust gas, a nitrogen oxide removing device for removing nitrogen oxide contained in combustion exhaust gas, and a combustion exhaust gas A carbon dioxide-containing gas and heat supply device equipped with a carbon monoxide and ethylene removal device for removing carbon monoxide and ethylene contained therein, and a purified gas supply device for supplying purified exhaust gas to a plant for crop production And the delivery method is described.

  Patent Document 2 also includes means for reducing nitrogen oxides and sulfur oxides in exhaust gas discharged from a kerosene combustion type warming machine to a concentration that does not affect plant growth, and contained in the exhaust gas. A device for supplying carbon dioxide to a horticultural facility comprising means for collecting and concentrating carbon dioxide, means for storing concentrated carbon dioxide, and means for supplying the stored carbon dioxide into the horticultural facility is described. ing.

  Further, in Patent Document 3, a carbonization furnace that carbonizes and gasifies woody biomass to generate carbides and decomposition gas, a waste heat boiler that burns decomposition gas from the carbonization furnace, and steam generated by the waste heat boiler Exhaust gas processing equipment such as a steam turbine and a generator that generates electricity using the exhaust gas, a dust collector that processes the exhaust gas discharged from the waste heat boiler, and facility horticulture equipment etc. into which the exhaust gas treated in the exhaust gas processing equipment is introduced. The biomass utilization system provided is described.

  Further, Patent Document 4 discloses a high-temperature combustion gas generator that burns biomass, a boiler that generates steam or hot water from exhaust gas discharged from the high-temperature combustion gas generator, and sulfur oxides in the exhaust gas discharged from the boiler. And a combustion gas processing apparatus for reducing or removing nitrogen oxides and the like, and a combustion gas utilization system including a green house and the like into which an exhaust gas containing carbon dioxide processed by the combustion gas processing apparatus is introduced.

  Furthermore, Patent Document 5 includes a combustion furnace that burns fuel, a boiler that generates steam using combustion heat of the combustion furnace, and a steam turbine and a generator that generate electric power using steam generated by the boiler. An exhaust gas supply system and an exhaust gas supply method including an exhaust gas high-precision purification facility that removes components harmful to plants contained in exhaust gas containing carbon dioxide supplied to a plant growing facility are described.

JP, 2016-036334, A Unexamined-Japanese-Patent No. 2012-016322 JP, 2006-191876, A WO 2009/038103 Unexamined-Japanese-Patent No. 2017-093393

  However, the carbon dioxide-containing gas and heat supply apparatus and method described in Patent Document 1, the carbon dioxide supply apparatus to a horticultural facility described in Patent Document 2, and the combustion gas utilization system described in Patent Document 4 are: Since none of them have a power generation device, the electricity used in the plant cultivation facility has to be supplied by the power from the electric power company, and there is a problem that the running cost becomes high.

  On the other hand, since the biomass utilization system described in Patent Document 3 and the exhaust gas supply system and exhaust gas supply method described in Patent Document 5 both include a power generation device, the power generated by the power generation device is used as a fan in the system or It can be used as a power source of equipment such as lighting, and the running cost in the facility horticultural equipment and plant growing equipment can be reduced.

  However, the biomass utilization system described in Patent Document 3 and the exhaust gas supply system and exhaust gas supply method described in Patent Document 5 do not effectively recover the excess heat possessed by the exhaust gas, but the facility exhausts the facility horticultural equipment or There is a problem that energy efficiency is poor because it is supplied to plant growing facilities.

  The present invention has been made to solve the above-described problems, and recovers excess heat of exhaust gas containing purified carbon dioxide supplied from an exhaust gas purification facility to a plant cultivation facility. It is a main object of the present invention to provide a combined plant and a method of recovering surplus heat of the combined plant, which is utilized in a power generation facility to increase energy efficiency and reduce the running cost of the power generation facility.

  In order to achieve the above object, a combined plant according to one aspect of the present invention is a boiler that recovers heat from exhaust gas containing carbon dioxide generated by burning fuel and generates steam, and a fuel saving device that further recovers heat from exhaust gas And a steam turbine driven by the steam of the boiler, a generator that generates electricity by driving the steam turbine, a condenser that condenses the exhaust steam discharged from the steam turbine, and a degassing process of the condensate from the condenser Power generation equipment including at least a deaerator, and an exhaust gas purification equipment having an exhaust gas duct for flowing exhaust gas generated from the power generation equipment to a plant cultivation facility and an exhaust gas purification processing unit for purifying exhaust gas flowing in the exhaust gas duct. In the combined plant, between the power generation facility and the exhaust gas purification facility, purification treatment is performed by at least a part of water for a boiler used in the power generation facility and the exhaust gas purification processing unit Heat exchange with the exhaust gas whose temperature is higher than that of the condensate, heating water for the boiler with the excess heat of the exhaust gas, and providing a surplus heat recovery system for returning the heated water for the boiler to the power generation facility It is characterized by

  In one embodiment, the surplus heat recovery apparatus is branched to a water supply line through which water for a boiler flows, and a water branch line that branches at least a part of water for a boiler flowing through the water supply line; It is interposed in the exhaust gas duct through which the exhaust gas purified by the purification processing unit flows, and heat exchange is performed between the boiler water supplied from the water branch line and the exhaust gas that is purified and has a higher temperature than the boiler water. A gas cooler heating the boiler water with exhaust gas and cooling the exhaust gas with the boiler water, and boiler water heated by the gas cooler downstream of the connection point between the water supply line and the water branch line And a water return line to be returned to the water supply line of

  In one embodiment, a water circulation line for returning a part of boiler water heated by the gas cooler and flowing through the water return line to the water branch line between the water branch line of the surplus heat recovery apparatus and the water return line Is preferably provided.

  In one embodiment, the surplus heat recovery device is a flow control valve that controls the flow rate of boiler water that is heated by the gas cooling device and returns from the water circulation line to the water branch line, and an exhaust gas duct downstream of the gas cooling device And a temperature detection controller for controlling the flow control valve by detecting the temperature of the purified exhaust gas flowing inside or the temperature of the water for the boiler flowing into the gas cooling device, the flow control valve Preferably, the control is performed based on the detected temperature from the temperature detection controller so that the gas cooling device is at a temperature that does not cause corrosion by the acid drain.

  In one embodiment, the flow control valve is preferably provided at a connection point between a water return line through which water for a boiler flows and a water circulation line or a water circulation line.

  In one embodiment, the water for the boiler is preferably a condensate discharged from a condenser, a makeup water supplied to a deaerator, or a boiler water supplied to a economizer .

  In one embodiment, the water supply line includes a condensate supply line that supplies condensate discharged from a condenser to a deaerator, a makeup water supply line that supplies makeup water to the deaerator, and deaeration. It is preferable to include a boiler feed water supply line for supplying boiler feed water from the vessel to the economizer.

  In one embodiment, the exhaust gas duct downstream of the gas cooling device is connected to a gas cooling ventilator that supplies air in the exhaust gas duct to lower the temperature of the purified exhaust gas to a predetermined temperature. Is preferred.

  In one embodiment, the exhaust gas purification facility is provided in an exhaust gas duct on the downstream side of the exhaust gas purification processing unit, and an exhaust gas supply ventilator that attracts the exhaust gas generated in the power generation facility into the exhaust gas duct; An exhaust gas circulation duct that connects the exhaust gas duct on the upstream side and the exhaust gas duct on the downstream side of the exhaust gas supply ventilator and returns the exhaust gas purified by the exhaust gas purification processing unit to the exhaust gas duct upstream of the exhaust gas purification processing unit; An exhaust gas flow control damper is further provided on an exhaust gas duct downstream of a connection between the circulation duct and the exhaust gas duct through which the purified exhaust gas flows, and which controls the flow rate of the exhaust gas supplied to the plant cultivation facility Is preferred.

  In one embodiment, the fuel is preferably a biomass fuel.

  A surplus heat recovery method of a combined plant according to an aspect of the present invention includes: a boiler that recovers heat from exhaust gas containing carbon dioxide generated by burning a fuel to generate steam; an economizer that further recovers heat from exhaust gas; Steam turbine driven by the steam of the boiler, a generator that generates electricity by driving the steam turbine, a condenser that condenses the exhaust steam discharged from the steam turbine, degassing that degasses the condensate from the condenser A combined plant comprising a power generation facility including at least a gas unit, an exhaust gas duct for flowing exhaust gas generated by the power generation facility to a plant cultivation facility, and an exhaust gas purification processing unit for purifying exhaust gas flowing in the exhaust gas duct And a process for extracting at least a portion of water for a boiler used in a power generation facility, and a process for purifying water and an exhaust gas for the extracted boiler. And heat-exchanged with the exhaust gas whose temperature is higher than that of the water for the boiler to heat the water for the boiler with the excess heat of the exhaust gas, and generate the water for the boiler heated by the excess heat of the exhaust gas And returning the equipment.

  In one embodiment, in the step of returning the water for the boiler heated by the excess heat of the exhaust gas to the power generation facility, the water for the boiler before heating a part of the heated water for the boiler by the excess heat of the exhaust gas It is characterized in that it further includes the step of returning.

  According to the combined plant of the present invention, a power generation facility for generating power by burning fuel and an exhaust gas purification facility for purifying exhaust gas generated in the power generation facility, the power generation facility is disposed between the power generation facility and the exhaust gas purification facility. Heat exchange is performed between at least a part of boiler water used internally and the exhaust gas that is purified by the exhaust gas purification processing unit of the exhaust gas purification facility and has a temperature higher than that of the boiler water Since there is a surplus heat recovery device that heats up the surplus heat and returns the heated boiler water to the power generation device, the surplus heat of the exhaust gas supplied from the exhaust gas purification facility to the plant cultivation facility is generated by the power generation facility. Can be recovered to the side, energy efficiency can be increased, fuel in the power generation facility can be reduced, and running cost can be reduced.

  Further, according to the combined plant of the present invention, the surplus heat recovery device comprises a water branch line for drawing out a portion of water for a boiler used in a power generation facility, and water for a boiler supplied from the water branch line. A gas cooling device for exchanging heat with the exhaust gas purified by the exhaust gas purification processing unit, a water return line for returning the boiler water heated by the exhaust gas by the gas cooling device to the deaerator side of the power generator, and gas cooling A water circulation line for returning a part of boiler water heated by the apparatus and flowing in the water return line back to the water branch line, the temperature of the boiler water flowing into the gas cooling apparatus The temperature can be raised to a temperature at which no acid drain is generated, and corrosion by the acid drain of the gas cooling device can be prevented.

  Furthermore, according to the combined plant of the present invention, the excess heat recovery device controls the flow rate of the condensate returning from the water circulation line to the water branch line, and the exhaust gas flowing through the exhaust gas duct downstream of the gas cooling device. The temperature detection controller which detects the temperature or the temperature of the water for the boiler flowing into the gas cooling device to control the flow control valve, and the temperature of the gas cooling device does not cause corrosion by the acid drain In addition, since the flow rate control valve is controlled by the temperature detection controller, corrosion due to the acid drain of the gas cooling device can be more reliably prevented.

  Furthermore, according to the combined plant of the present invention, gas cooling is performed to supply the air in the atmosphere to the exhaust gas duct downstream of the gas cooling device to reduce the temperature of the purified exhaust gas to a predetermined temperature. Since the ventilator is connected, the exhaust gas of the temperature suitable for the growth of the plant in a plant cultivation facility can be supplied to a plant cultivation facility.

Furthermore, according to the combined plant of the present invention, an exhaust gas duct for flowing the exhaust gas generated by the power generation facility to the plant cultivation facility, an exhaust gas purification processing unit for purifying exhaust gas flowing through the exhaust gas duct, and a downstream side of the exhaust gas purification processing unit The exhaust gas supply ventilator installed in the exhaust gas duct, the exhaust gas circulation duct for returning the exhaust gas purified by the exhaust gas purification processing unit to the exhaust gas duct upstream of the exhaust gas purification processing unit, the exhaust gas supply ventilator and the exhaust gas circulation duct Since the exhaust gas flow rate control damper provided downstream of the exhaust gas duct is provided, only the necessary amount of exhaust gas containing carbon dioxide can be supplied to the plant cultivation facility, and excess exhaust gas is circulated by the exhaust gas circulation duct. Thus, it can be returned to the exhaust gas duct upstream of the exhaust gas purification processing section.
As a result, according to the combined plant of the present invention, even if the exhaust gas has a high concentration of harmful components generated in the power generation facility, it is diluted by the exhaust gas that has been purified and circulated before flowing into the exhaust gas purification treatment unit. As a result, the concentration of harmful components is reduced, and it becomes easier to purify the exhaust gas in the exhaust gas purification treatment section, and the exhaust gas purification performance is improved. In addition, when all the exhaust gas purified by the exhaust gas purification processing unit is returned to the upstream side of the exhaust gas purification processing unit by the exhaust gas circulation duct, the exhaust gas is repeatedly purified by the exhaust gas purification processing unit. The concentration of harmful components in the exhaust gas can be reliably reduced to a reference value or less.

  Furthermore, according to the combined plant of the present invention, since biomass fuel is used as the fuel, the amount of carbon dioxide emissions can be reduced.

  According to the surplus heat recovery method for a combined plant of the present invention, a purification process is performed in the step of extracting at least part of boiler water used in the power generation facility, and the extracted boiler water and exhaust gas purification processing unit. Heat exchanging with exhaust gas having a temperature higher than that of boiler water to heat the boiler water with surplus heat of the exhaust gas, and returning the boiler water heated with the surplus heat of the exhaust gas to the power generation facility; Therefore, it is possible to recover the excess heat of the exhaust gas supplied from the exhaust gas purification equipment to the plant cultivation facility to the power generation equipment side, increase energy efficiency, and use the fuel of the power generation equipment. This can reduce the running cost.

  Further, according to the surplus heat recovery method of the combined plant of the present invention, in the step of returning the water for the boiler heated by the excess heat of the exhaust gas to the power generation facility, a part of the heated water for the boiler is surplus for the exhaust gas. Since the process of returning to the boiler water before heating with heat is further included, the temperature of the boiler water at the time of heat exchange between the boiler water and the exhaust gas can be raised to a temperature at which the acid drain does not occur. It is possible to prevent the corrosion of the equipment by the acid drain.

It is a schematic system diagram which shows an example of the complex plant which concerns on embodiment of this invention, and shows the structure of the power generation equipment of a complex plant. It is a schematic system diagram which similarly shows an example of a complex plant and shows the structure of the exhaust gas purification equipment of a complex plant. It is a schematic explanatory drawing of the surplus heat recovery device which recovers the surplus heat of the exhaust gas purified by exhaust gas purification equipment to the power generation equipment side using the condensate of the steam turbine of a power generation device. It is a schematic explanatory drawing which shows the other example of the excessive heat recovery device which collect | recovers the excessive heat of the waste gas purified by exhaust gas purification equipment to the electric power generation equipment side using makeup water to a deaerator. It is a schematic explanatory drawing which shows the further another example of the surplus heat collection | recovery apparatus which collect | recovers the surplus heat of the waste gas purified in the exhaust gas purification equipment to the power generation equipment side using boiler feed water to the economizer.

  Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

  1 to 3 show an example of a complex plant according to an embodiment of the present invention. The complex plant generates steam S by recovering heat from exhaust gas G generated by burning fuel, and uses the steam S. The power generation facility 1 that generates power and the exhaust gas G generated by the power generation facility 1 is partly (or all) purified, and the exhaust gas G containing the purified carbon dioxide is converted into plant cultivation facilities 2 (agricultural crops and An exhaust gas purification facility 3 for supplying plants such as horticultural plants to a greenhouse or plant factory) is provided, and between the power generation facility 1 and the exhaust gas purification facility 3, the carbon dioxide purified by the exhaust gas purification facility 3 A surplus heat recovery device 4 that recovers at least a part of surplus heat of the exhaust gas G containing carbon to the power generation equipment 1 side is provided.

  Here, surplus heat is the amount of heat remaining after subtracting the amount of heat used in the plant cultivation facility 2 from the amount of heat of the exhaust gas G purified by the exhaust gas purification facility 3.

  As shown in FIG. 1, the power generation facility 1 of the combined plant includes a boiler 5 that generates heat S from a high-temperature exhaust gas G obtained by fuel combustion and generates steam S, and boiler feed water using the exhaust gas G discharged from the boiler 5. An economizer for heating W ″, an air preheater 7 for preheating secondary combustion air supplied to the boiler 5 with the exhaust gas G, and a dust collector 8 for collecting the soot and dust in the exhaust gas G (for example, bugs) Driven by the steam S from the boiler 5 and the induction fan 9 for inducing the exhaust gas G in the boiler 5 and the exhaust pipe 10 such as a chimney for discharging the exhaust gas G passing through the induction Steam turbine 11, a generator 12 for generating electric power by driving the steam turbine 11, a condenser 13 for converting exhaust steam S 'discharged from the steam turbine 11 into condensed water W, and a condenser 13 Revival A deaerator 14 which heats and degass W by the extracted steam S ′ ′ from the steam turbine 11, a condensate pump 15 which supplies condensed water W from the condenser 13 to the deaerator 14 and a deaerator The boiler feed pump 16 etc. which supply the condensed water W from 14 to the economizer 6 are provided.

  Moreover, the boiler 5 of the power generation facility 1 recovers heat from high temperature exhaust gas G obtained by combustion of fuel such as biomass, fossil fuel, waste and the like to generate steam S.

  In the present embodiment, a traveling stoker boiler that uses biomass such as wood-based biomass, plant-based biomass, and livestock-based biomass as fuel is used for the boiler 5.

  As shown in FIG. 1, the traveling stalker boiler includes a traveling stalker 17, a combustion chamber 18, a steam drum 19, a water drum 20, a water tube group 21, a primary superheater 22, a secondary superheater 23, and the like. The high-temperature exhaust gas G generated in the traveling stoker 17 or the combustion chamber 18 generates steam S, and the generated steam S is further heated in the primary superheater 22 and the secondary superheater 23.

  In FIGS. 1 to 3, reference numeral 24 denotes a steam supply line for supplying steam S to the steam turbine 11, 25 denotes an exhaust steam line connecting the steam turbine 11 and the condenser 13, and 26 denotes the condenser 13 and degassing. Condenser feed line connecting the boiler 14, 27 an ejector condenser or ground condenser interposed in the condensate feed line 26, 28 connect the deaerator 14 with the economizer 6 and the economizer 6 with the boiler 5 respectively A boiler feed water supply line 29 is a bleed steam supply line connecting the steam turbine 11 and the deaerator 14, and 30 is a makeup water supply line for feeding a makeup water W ′ to the deaerator 14.

  Further, a condensate feed line 26 for feeding the condensate W discharged from the condenser 13 to the deaerator 14, a makeup water feed line 30 for feeding the makeup water W ′ to the deaerator 14, and the deaerator The boiler feed water supply line 28 that supplies the boiler feed water W ″ to the economizer 14 from 14 is referred to as a water supply line.

  Thus, according to the power generation facility 1, the steam S generated in the boiler 5 is superheated by the primary superheater 22 and the secondary superheater 23 of the boiler 5 and then supplied to the steam turbine 11 to be supplied to the steam turbine 11. To generate power by the generator 12.

  Exhaust steam S ′ discharged from the steam turbine 11 is converted to the condensed water W by the condenser 13 and then supplied to the deaerator 14 by the condensate pump 15 through the ejector condenser 27 or the ground condenser 28. The deaerator 14 is appropriately supplied with makeup water W ′ from which impurities have been removed.

  The condensate W supplied to the deaerator 14 is heated and deaerated by the extracted steam S ″ from the steam turbine 11 (or steam S obtained by extracting a part of the steam S supplied to the steam turbine 11). After that, it is sent to the economizer 6 by the boiler feed pump 16, and is heated by the exhaust gas G and supplied to the boiler 5 here.

  On the other hand, the exhaust gas G discharged from the boiler 5 is sequentially led to the economizer 6 and the air preheater 7, and heats the boiler feed water W ′ ′ by the economizer 6 and secondary combustion air by the air preheater 7. After preheating, it flows into the dust collector 8 where dust in the exhaust gas G is removed, and is discharged into the atmosphere from the stack 10 such as a chimney through the induction fan 9. At this time, part of the exhaust gas G Is withdrawn from the stack 10 such as a chimney and supplied to the exhaust gas purification equipment 3 to be described later.

  In the present embodiment, about 20% of the exhaust gas G that has passed through the induction ventilator 9 is supplied to the exhaust gas purification facility 3.

  The exhaust gas purification facility 3 of the complex plant extracts a part of the exhaust gas G generated by the power generation facility 1 (about 20% of the exhaust gas G), and a substance (for example, sulfur oxide, After removing nitrogen oxides, carbon monoxide, ethylene, etc.), exhaust gas G containing purified carbon dioxide is supplied to the plant cultivation facility 2.

  That is, as shown in FIG. 2, the exhaust gas purification facility 3 includes an exhaust gas duct 31 for flowing a part of the exhaust gas G generated by the power generation facility 1 to the plant cultivation facility 2 and an exhaust gas purification processing unit interposed in the exhaust gas duct 31. 32, an exhaust gas supply ventilating device 33 interposed in the exhaust gas duct 31 downstream of the exhaust gas purification processing unit 32, an exhaust gas duct 31 upstream of the exhaust gas purification processing unit 32, and exhaust gas downstream of the exhaust gas supply ventilator 33 The exhaust gas circulation duct 34 connecting with the duct 31, the exhaust gas circulation damper 35 interposed in the exhaust gas circulation duct 34, and the connection portion between the exhaust gas circulation duct 34 and the exhaust gas duct 31 through which the purified exhaust gas G flows Exhaust gas flow control damper 36 interposed in the exhaust gas duct 31 on the side of the exhaust gas, and an exhaust gas blocking damper interposed in the exhaust gas duct 31 downstream of the exhaust gas flow control damper 36 And 37, and the exhaust gas analyzer 38 provided in the exhaust gas duct 31 between the exhaust gas purification unit 32 and the exhaust gas supply ventilator 33, a control unit 39 for controlling the respective dampers 35 and 36.

  Here, the upstream side is the upstream side in the flow direction of the exhaust gas G, and the downstream side is the downstream side in the flow direction of the exhaust gas G.

  The upstream end of the exhaust gas duct 31 is branched in the middle of an exhaust pipe 10 such as a chimney of the power generation facility 1, and the downstream end is connected to the plant cultivation facility 2, This is for flowing a part of the exhaust gas G discharged from the facility 1 to the plant cultivation facility 2.

  In the present embodiment, about 20% of the exhaust gas G discharged from the exhaust stack 10 such as a chimney is made to flow to the plant cultivation facility 2. Further, at the upstream end of the exhaust gas duct 31, an exhaust gas supply damper 40 is interposed which supplies the exhaust gas G from the exhaust cylinder 10 such as a chimney to the exhaust gas duct 31 side.

  The exhaust gas purification processing unit 32 removes substances (for example, sulfur oxides, nitrogen oxides, carbon monoxide, ethylene, and the like) that cause damage to the growth of plants from the exhaust gas G, and purifies them. , A neutralizer input unit 42, an activated carbon input unit 43, a gas reheater 44, a carbon monoxide / ethylene removal device 45, and a nitrogen oxide removal device 46.

  The dust collector 41 removes soot dust, acid gas and dioxins contained in the exhaust gas G, and a bag filter is used for the dust collector 41. When the temperature of the exhaust gas G is 200 ° C. or less, the bag filter uses a filter cloth formed of tetrafluoroethylene resin or glass fiber, and when the temperature of the exhaust gas G is higher than the temperature, Ceramic filters are used.

  The neutralizing agent feeding portion 42 is for blowing a neutralizing agent for neutralizing the exhaust gas G containing an acid gas such as HCl or the like into the exhaust gas duct 31 on the upstream side of the dust collector 41, and is illustrated Although not provided, a medicine storage tank, a medicine quantitative supply device, a transport blower and the like are provided. When the temperature of the exhaust gas G is 200 ° C. or lower, this neutralizing agent input unit 42 uses an inexpensive neutralizing agent such as slaked lime, and when the temperature of the exhaust gas G is high (in the case of about 300 ° C.) Use expensive neutralizer such as baking soda.

  In the present embodiment, since the temperature of the exhaust gas G is about 160 ° C. on the upstream side of the exhaust gas duct 31, the neutralizing agent charging unit 42 blows slaked lime into the exhaust gas duct 31.

  The activated carbon charging unit 43 blows activated carbon into the exhaust gas duct 31 on the upstream side of the dust collector 41, makes dioxins and heavy metals adsorbed on the activated carbon, and promotes removal processing of dioxins and the like in the dust collector 41 (bug filter). Yes, although not shown in the figure, an activated carbon storage tank, an activated carbon quantitative supply device, a transport blower and the like are provided.

  The gas reheater 44 heats the exhaust gas G discharged from the dust collector 41 to a temperature suitable for purification processing by the carbon monoxide / ethylene removal device 45 or the nitrogen oxide removal device 46, and a heating source , Steam S from the steam drum 19 of the boiler 5 is used.

  The carbon monoxide / ethylene removal device 45 removes carbon monoxide contained in the exhaust gas G and removes ethylene by oxidizing carbon monoxide using an oxidation catalyst in the device. . Instead of the oxidation catalyst, an adsorbent that removes carbon monoxide and ethylene contained in the exhaust gas G may be used.

  The nitrogen oxide removing device 46 is for blowing ammonia into the exhaust gas G from the ammonia injector 47 and decomposing nitrogen oxides in the exhaust gas G into nitrogen gas in the presence of ammonia on the surface of the NOx removal catalyst in the device. is there. The amount of blown ammonia is set so that the concentration of nitrogen oxide on the downstream side of the nitrogen oxide removing device 46 is detected, and the concentration of nitrogen oxide is equal to or less than a predetermined concentration.

  The exhaust gas supply ventilator 33 is interposed in the exhaust gas duct 31 on the downstream side of the nitrogen oxide removing device 46, attracts a part of the exhaust gas G from the exhaust cylinder 10 such as a chimney, and the exhaust gas G is drawn into the exhaust gas duct 31. To flow the The exhaust gas supply ventilator 33 includes a motor having a variable speed control mechanism, and is variably controlled by the first flow rate instruction controller 49.

  The first flow rate indicating controller 49 receives the measured value of the exhaust gas G flow rate in the exhaust gas duct 31 from the first flow sensor 49a provided in the exhaust gas duct 31 on the downstream side of the dust collector 41, and uses this value as a predetermined value. To the exhaust gas supply ventilator 33 (or a signal for maintaining this value within a desired range).

  The exhaust gas circulation duct 34 connects the exhaust gas duct 31 on the upstream side of the dust collector 41 and the exhaust gas duct 31 on the downstream side of the exhaust gas supply ventilating machine 33, and an exhaust gas G containing carbon dioxide purified by the exhaust gas purification processing unit 32. Is returned to the exhaust gas duct 31 upstream of the exhaust gas purification processing unit 32 (upstream of the dust collector 41).

  The exhaust gas circulation damper 35 controls the flow rate of the purified exhaust gas G that is returned to the upstream side of the exhaust gas purification processing unit 32 by adjusting the opening thereof and adjusting the opening area of the exhaust gas circulation duct 34. . The exhaust gas circulation damper 35 is controlled by the second flow rate instruction controller 50.

  The second flow rate indicating controller 50 receives the measured value of the exhaust gas G flow rate in the exhaust gas duct 31 from the second flow sensor 50a provided in the exhaust gas duct 31 on the downstream side of the exhaust gas cutoff damper 37, and sets this value to a predetermined value. A signal for maintaining the value of (or a signal for maintaining the value within a desired range) is sent to the exhaust gas circulation damper 35 and the exhaust gas flow control damper 36.

  The exhaust gas flow rate control damper 36 controls the flow rate of the exhaust gas G containing carbon dioxide supplied from the exhaust gas duct 31 to the plant cultivation facility 2 by adjusting the opening degree and adjusting the opening area of the exhaust gas duct 31 It is. The exhaust gas flow rate control damper 36 is controlled by the second flow rate instruction controller 50 so that the flow rate of the exhaust gas G supplied from the exhaust gas duct 31 to the plant cultivation facility 2 becomes a predetermined flow rate.

  The exhaust gas blocking damper 37 blocks the flow of the purified exhaust gas G supplied from the exhaust gas duct 31 to the plant cultivation facility 2.

  The exhaust gas analyzer 38 measures the concentration of each component (carbon monoxide, carbon dioxide, oxygen, sulfur oxide, nitrogen oxide, hydrogen chloride, etc.) in the exhaust gas G purified by the exhaust gas purification processing unit 32. It is a thing.

  The control unit 39 controls the flow rate of the exhaust gas G containing carbon dioxide so that the carbon dioxide concentration in the plant cultivation facility 2 becomes constant, and the control unit 39 controls the concentration of carbon dioxide in the plant cultivation facility 2 and carbon dioxide The signal of the required amount is received, and the opening degree of the exhaust gas flow control damper 36 is adjusted to control the flow rate of the exhaust gas G containing carbon dioxide. Further, the control unit 39 receives a detection signal of each component concentration in the exhaust gas G from the exhaust gas analyzer 38, and controls the exhaust gas circulation damper 35 and the exhaust gas flow rate control damper 36, respectively.

  Thus, according to the exhaust gas purification system 3, the exhaust gas duct 31, the exhaust gas flow rate control damper 36, and the exhaust gas blocking damper 37 are opened, and the exhaust gas supply ventilator 33 is driven. A portion of the exhaust gas G discharged from the exhaust stack 10 is drawn to the exhaust gas duct 31 side, and the drawn exhaust gas G is purified by the exhaust gas purification processing unit 32 interposed in the exhaust gas duct 31 to the plant cultivation facility 2 Can be supplied.

  That is, the exhaust gas G drawn into the exhaust gas duct 31 from the exhaust cylinder 10 such as a chimney flows to the dust collector 41 side in the exhaust gas duct 31, and the neutralizing agent input part 42 into the exhaust gas G on the upstream side of the dust collector 41. , Slaked lime and other neutralizing agents, and activated carbon is blown from the activated carbon charging section 43. At this time, the temperature of the exhaust gas G is approximately 160 ° C.

  The exhaust gas G into which the neutralizing agent and activated carbon have been blown flows into the dust collector 41, where the dust in the exhaust gas G, the reactive products of the neutralizing agent and acid gas, and the dioxins adsorbed on the activated carbon are removed. .

  Exhaust gas G from which dust, acid gas and dioxins have been removed by the dust collector 41 flows into the gas reheater 44 where it is suitable for purification treatment with the carbon monoxide / ethylene removal device 45 or the nitrogen oxide removal device 46 It is heated to a low temperature. At this time, the exhaust gas G is heated to about 200 ° C. by the gas reheater 44.

  The exhaust gas G heated by the gas reheater 44 sequentially flows into the carbon monoxide / ethylene removal device 45 and the nitrogen oxide removal device 46, and the carbon monoxide / ethylene removal device 45 removes the exhaust gas G by the oxidation catalyst. Carbon monoxide and ethylene are removed, and nitrogen oxide in exhaust gas G is decomposed by decomposing nitrogen oxides in exhaust gas G into nitrogen gas in the presence of ammonia on the surface of the NOx removal catalyst in nitrogen oxide removal apparatus 46. Things are removed. The temperature of the exhaust gas G that has passed through the carbon monoxide / ethylene removal device 45 and the nitrogen oxide removal device 46 is about 190 ° C.

  Thus, the exhaust gas G containing carbon dioxide purified by the exhaust gas purification processing unit 32 is supplied to the plant cultivation facility 2 by the exhaust gas supply ventilator 33. Further, according to the properties of the exhaust gas G exiting the exhaust gas supply ventilator 33, a part of the exhaust gas G or all the exhaust gas G is returned to the exhaust gas duct 31 on the upstream side of the exhaust gas purification processing unit 32 by the exhaust gas circulation duct 34. .

  Since the exhaust gas purification system 3 is provided with the exhaust gas flow control damper 36 on the downstream side of the exhaust gas purification processing unit 32, the exhaust gas flow control damper 36 significantly changes the supply amount of the exhaust gas G supplied to the plant cultivation facility 2 Even in this case, the drift of the exhaust gas G is less likely to occur inside the dust collector 41, the carbon monoxide / ethylene removal device 45, and the nitrogen oxide removal device 46 of the exhaust gas purification processing unit 32. Exhaust gas purification performance is exhibited stably.

  In addition, since the exhaust gas purification facility 3 includes the exhaust gas circulation duct 34 for returning the exhaust gas G purified by the exhaust gas purification processing unit 32 into the exhaust gas duct 31 on the upstream side of the exhaust gas purification processing unit 32, the plant cultivation facility 2 The amount of exhaust gas G corresponding to the amount of carbon dioxide required for the operation can be supplied to the plant cultivation facility 2 by the exhaust gas flow control damper 36, while the remaining purified exhaust gas G (surplus exhaust gas G) is supplied. The exhaust gas can be returned to the exhaust gas duct 31 on the upstream side of the exhaust gas purification processing unit 32 by flowing through the exhaust gas circulation duct 34.

  As a result, the concentration of each harmful component in the exhaust gas G on the upstream side of the exhaust gas purification processing unit 32 is lower than the concentration of each harmful component in the exhaust gas G discharged from the power generation facility 1. The exhaust gas G can be easily purified by the processing unit 32. Further, even when the concentration of any component in the exhaust gas G discharged from the power generation facility 1 is increased, the exhaust gas G is diluted by the purified exhaust gas G circulated by the exhaust gas circulation duct 34. This reduces the concentration of the component, making it easier to purify the exhaust gas G in the exhaust gas purification processing unit 32.

  Furthermore, since the exhaust gas purification facility 3 connects the exhaust gas circulation duct 34 to the exhaust gas duct 31 on the upstream side of the exhaust gas flow control damper 36, regardless of the opening degree of the exhaust gas flow control damper 36, in the exhaust gas circulation duct 34 The exhaust gas G can always flow, the condensation of moisture in the exhaust gas G hardly occurs in the exhaust gas duct 31, and corrosion in the exhaust gas duct 31 due to condensation of moisture in the exhaust gas G can be prevented.

  Furthermore, in the exhaust gas purification facility 3, the exhaust gas flow rate when the concentration of at least one component among harmful components in the exhaust gas G exceeds the predetermined reference value after the purification treatment of the exhaust gas G by the exhaust gas purification processing unit 32. The control damper 36 or the gas blocking damper 37 or both of the dampers 36 and 37 are closed to stop the supply of the exhaust gas G to the plant cultivation facility 2 and all the exhaust gas G is circulated in the exhaust gas purification processing unit 32 by the exhaust gas circulation duct 34 Let Then, the exhaust gas G is repeatedly purified by the exhaust gas purification processing unit 32 and is purified until the concentration of each harmful component in the exhaust gas G is equal to or lower than a reference value. Supplying the flue gas G containing carbon dioxide to the plant cultivation facility 2 promptly by resuming the supply of the exhaust gas G to the plant cultivation facility 2 when each harmful component in the exhaust gas G becomes less than a predetermined reference value be able to.

  Further, when the exhaust gas purification equipment 3 stops supplying the exhaust gas G to the plant cultivation facility 2 for a predetermined time or more, such as at night, the gas cutoff damper 37 or the exhaust gas flow control damper 36 or both dampers 36, 37 is closed, and the exhaust gas supply ventilator 33 is driven to flow the exhaust gas G purified and processed by the exhaust gas purification processing unit 32 into the exhaust gas circulation duct 34 to circulate in the exhaust gas purification processing unit 32 and further exhaust gas reheater By heating the exhaust gas G by 44, condensation of water in the exhaust gas G becomes difficult to occur in the exhaust gas duct 31 or in the exhaust gas circulation duct 34, and the inside of the exhaust gas duct 31 or exhaust gas circulation duct 34 due to the condensation of water in the exhaust gas G It can prevent internal corrosion. Moreover, even after the supply of the exhaust gas G to the plant cultivation facility 2 is stopped for a predetermined time or more, if the dampers 36 and 37 are opened, the exhaust gas G containing carbon dioxide is supplied to the plant cultivation facility 2 in a short time. Can.

  Between the power generation facility 1 and the exhaust gas purification facility 3 of the combined plant, at least a part of the boiler water used in the power generation facility 1 and the exhaust gas purification facility 3 are purified by the boiler water. A surplus heat recovery device 4 is provided which heats the boiler exhaust water with the excess heat of the exhaust gas G by heat exchange with the exhaust gas G having a high temperature, and supplies the heated boiler water to the power generation facility 1 There is.

  The boiler water used in the power generation facility 1 refers to the condensate W discharged from the condenser 13, the makeup water W 'supplied to the deaerator 14 or the economizer 6 It refers to the boiler feed water W ′ ′ supplied to.

  As shown in FIG. 3, the surplus heat recovery device 4 is connected in a branched manner to a water supply line in which water for a boiler flows, and a water branch line 51 for branching at least a part of water for a boiler flowing in the water supply line And the exhaust gas duct through which the exhaust gas G purified by the exhaust gas purification processing unit 32 flows, and the water for the boiler supplied from the water branch line 51 for purification and the temperature is higher than the water for the boiler A gas cooling device 52 that heat-exchanges the water for the boiler with the exhaust gas G and cools the exhaust gas G with the water for the boiler, and a gas cooling device feed water pump 53 interposed in the water branch line 51. Water return line 54 for returning boiler water heated by the gas cooling device 52 to the water supply line downstream of the connection point between the water supply line and the water branch line 51; 4, a water circulation line 55 for returning a part of boiler water to the water branch line 51, a flow control valve 56 for controlling the flow rate of boiler water returning from the water circulation line 55 to the water branch line 51, and a flow control valve And 56. A first temperature detection controller 57 that controls 56.

In the present embodiment, the condensate W discharged from the condenser 13 is used as boiler water.
Further, in the present embodiment, the water supply line is a condensed water supply line 26 that supplies the condensed water W discharged from the condenser 13 to the deaerator 14.

  Specifically, the water branch line 51 is branchedly connected to a condensed water supply line 26 which supplies condensed water W discharged from the condenser 13 at one end to the deaerator 14 and the other end The part is connected to the gas cooling device 52, and at least a part of the condensate W flowing through the condensate supply line 26 is branched to the gas cooling device 52 side. The water branch line 51 is formed by metal piping.

  The gas cooling device 52 is interposed in the exhaust gas duct 31 through which the exhaust gas G containing carbon dioxide purified by the exhaust gas purification processing unit 32 of the exhaust gas purification facility 3 flows, and is supplied from the condensate branch line 51 The water W and the exhaust gas G purified by the exhaust gas purification processing unit 32 and having a temperature higher than that of the condensate W are heat exchanged, and the condensate W is heated by the excess heat of the exhaust gas G. The exhaust gas cooling device 52 includes a casing 52a interposed in the exhaust gas duct 31 downstream of the gas blocking damper 37, and a heat transfer pipe 52b disposed in the casing 52a, and the upstream of the heat transfer pipe 52b A water branch line 51 is connected to the side end, and a water return line 54 is connected to the downstream end of the heat transfer tube 52b.

  The gas cooling device feed pump 53 is interposed in the water branch line 51, and guides at least a part of the condensate W flowing through the condensate feed line 26 to the water branch line 51 to supply it to the gas cooling device 52 It is.

  One end of the water return line 54 is connected to the downstream end of the heat transfer pipe 52 b of the gas cooling device 52, and the other end is downstream of the connection point between the condensate supply line 26 and the water branch line 51. The condensed water W, which is connected to the condensed water supply line 26 and heated by heat exchange in the gas cooling device 52, is connected to the condensed water supply line downstream of the connection point between the condensed water supply line 26 and the water branch line 51. Return to 26. The water return line 54 is formed by metal piping.

  The water circulation line 55 is provided between the water branch line 51 and the water return line 54, and branches a part of the heated condensate W flowing through the water return line 54 through the gas cooling device 52. It is returned to the line 51. The water circulation line 55 is formed by a metal pipe, one end of which is connected to the water branch line 51 on the upstream side of the water supply pump 53 of the gas cooling device, and the other end is provided in the water return line 54. Are connected to the flow control valve 56.

  The flow rate control valve 56 is provided at the connection between the water return line 54 and the water circulation line 55, and controls the flow rate of the heated condensate W returned from the water circulation line 55 to the water branch line 51. As the flow control valve 56, a three-way valve capable of flow control is used.

  The first temperature detection controller 57 detects the temperature of the exhaust gas G on the downstream side of the gas cooling device 52 with the first temperature sensor 57a, and based on the detection signal from the first temperature sensor 57a, the flow rate control valve. The control signal is transmitted to 56 to control the flow control valve 56. The temperature of the condensate W flowing into the gas cooling device 52 from the condensate branch line 51 causes the gas cooling device 52 to be corroded by acidic drain. The flow control valve 56 is controlled so that the temperature does not reach.

  In the exhaust gas purification facility 3, the temperature of the exhaust gas G containing carbon dioxide purified by supplying air in the exhaust gas duct 31 to the exhaust gas duct 31 on the downstream side of the gas cooling device 52 is set in the plant. A gas-cooled ventilator 58 for reducing the temperature to a predetermined temperature suitable for the growth of plants in the cultivation facility 2 is connected.

  The gas cooling ventilator 58 includes a motor having a variable speed control mechanism, and is variably controlled by the second temperature instruction controller 59.

  The second temperature indicating controller 59 is a measurement value of the exhaust gas G temperature in the exhaust gas duct 31 from the second temperature sensor 59a provided in the exhaust gas duct 31 downstream of the location where the gas cooling ventilator 58 is connected. And a signal for maintaining this value at a predetermined value (or a signal for maintaining this value within a desired range) is sent to the gas cooling ventilator 58.

  According to the surplus heat recovery device 4, the exhaust gas G purified by the exhaust gas purification facility 3 is driven by the gas cooling device feed pump 53 so as to recover the condensate from the condenser 13 of the power generation facility 1. It can be cooled by W and the excess heat possessed by the exhaust gas G can be recovered to the power generation facility 1 side.

  That is, part of the condensate W discharged from the condenser 13 and flowing through the condensate supply line 26 is drawn from the condensate supply line 26 by the drive of the gas cooling device feed pump 53 and flows to the water branch line 51.

  In the present embodiment, the amount of condensate W discharged from the condenser 13 is about 36.5 tons per hour. The amount of condensate W taken out from the condensate supply line 26 is about 12.7 tons per hour. Furthermore, the temperature of the condensate W flowing from the condensate supply line 26 to the water branch line 51 is about 54 ° C.

  Condensate W that has flowed into the water branch line 51 flows into the heat transfer pipe 52 b of the gas cooling device 52 through the gas cooling device feed water pump 53. At this time, if the temperature of the condensate W flowing into the heat transfer tube 52b of the gas cooling device 52 is too low, an acidic drain is generated in the gas cooling device 52 to corrode the heat transfer tube 52b and the casing 52a of the gas cooling device 52. Sometimes. Therefore, before the condensed water W flows into the gas cooling device 52, part of the condensed water W heated by the gas cooling device 52 is returned to the water branching line 51 from the water circulation line 55, and the condensed water W flowing in the water branching line 51 To prevent the generation of acid drain in the gas cooler 52.

  In the present embodiment, the condensate W at about 90 ° C. is returned to the water branch line 51 from the water circulation line 55, and the temperature of the condensate W flowing through the water branch line 51 becomes about 80 ° C. at the inlet side of the gas cooling device 52. It's adjusted.

  The condensate W raised to a temperature of about 80 ° C. flows from the water branch line 51 into the heat transfer pipe 52b of the gas cooling device 52, and flows through the inside of the casing 52a of the gas cooling device 52 while passing through the heat transfer pipe 52b. Heat is exchanged with the treated exhaust gas G, and heat is recovered from the exhaust gas G and heated.

In this embodiment, the condensate W that has exited the gas cooling device 52 is heated by the exhaust gas G of about 190 ° C. that passes through the gas cooling device 52, and becomes condensate W of about 90 ° C. Further, the flow rate of the purified exhaust gas G passing through the gas cooling device 52 is about 14,000 m ³ N / h.

  The condensate W heated to about 90 ° C. by the gas cooling device 52 flows into the water return line 54, passes through the flow rate control valve 56, and is supplied from the water return line 54 to the condensate supply line 26. The mixture is mixed with the condensed water W flowing to raise the temperature of the condensed water W. Further, part of the condensate W flowing through the water return line 54 flows from the flow control valve 56 to the water circulation line 55, and is mixed with the condensate W flowing from the water circulation line 55 through the water branch line 51 to obtain the temperature of the condensate W increase. At this time, the flow control valve 56 detects the temperature of the exhaust gas G on the outlet side of the gas cooling device 52 by the temperature sensor 57a of the temperature detection controller 57, and this temperature does not cause corrosion due to acidic drain of the gas cooling device 52. The condensate W, which is controlled by the control signal from the temperature detection controller 57 and heated to about 90 ° C. by the gas cooling device 52, returns to the water branch line 51 via the water circulation line 55 so that the temperature is reached. I have to.

  The heated condensate W supplied from the water return line 54 to the condensate feed line 26 is mixed with the condensate W flowing through the condensate feed line 26 to raise the temperature of the condensate W, and then the deaerator 14 is produced. Supplied to

  In the present embodiment, the condensate W at about 54 ° C. flowing through the condensate feed line 26 is mixed with the condensate W at about 90 ° C. supplied from the water return line 54 to become the condensate W at about 67 ° C. Is supplied to the deaerator 14.

  As described above, the above-described combined plant includes the power generation facility 1 and the exhaust gas purification facility 3 that purifies and processes the exhaust gas G generated by the power generation facility 1, and between the power generation facility 1 and the exhaust gas purification facility 3, the power generation facility 1 Heat exchange is performed between at least a portion of the condensate W discharged from the condenser 13 and the exhaust gas G which is purified by the exhaust gas purification facility 3 and whose temperature is higher than that of the condensate W. Since the surplus heat recovery device 4 that heats the heat and supplies the heated condensate W to the deaerator 14 is provided, the surplus in the exhaust gas G supplied from the exhaust gas purification equipment 3 to the plant cultivation facility 2 The heat can be recovered to the power generation facility 1, the energy efficiency can be improved, and the fuel of the power generation facility 1 can be reduced to reduce the running cost.

  FIG. 4 shows another example of the surplus heat recovery device 4. The surplus heat recovery device 4 is provided between the power generation facility 1 and the exhaust gas purification facility 3, and the makeup water W supplied to the deaerator 14. Heat was exchanged between at least a part of the exhaust gas G and at least a part of the exhaust gas purification facility 3 and the exhaust gas G having a temperature higher than that of the makeup water W 'was heated to heat the makeup water W' with excess heat of the exhaust gas G The makeup water W ′ is to be supplied to the deaerator 14.

  That is, the surplus heat recovery device 4 shown in FIG. 4 includes a water branch line 51, a gas cooling device 52, a gas cooling device feed pump 53, a water return line 54, a water circulation line 55, and a flow control valve 56. A first temperature detection controller 57 is provided, and the upstream end of the water branch line 51 is communicatively connected to the makeup water supply line 30, and the downstream end of the water return line 54 is a water branch line 51. Are connected to the make-up water supply line 30 downstream of the connection place of the make-up water supply line 30 in a continuous manner.

  The excess heat recovery apparatus 4 shown in FIG. 4 has excess heat recovery shown in FIG. 3 except that the connection point at the upstream end of the water branch line 51 and the connection point at the downstream end of the water return line 54 are changed. The structure is the same as that of the device 4, and the same reference numerals are assigned to the same parts and members as the surplus heat recovery device 4 shown in FIG. 3.

  The complex plant provided with the surplus heat recovery device 4 shown in FIG. 4 can also recover the surplus heat of the exhaust gas G supplied from the exhaust gas purification equipment 3 to the plant cultivation facility 2 to the power generation equipment 1 side. While being able to improve efficiency, the fuel of the power generation facility 1 can be reduced, and the running cost can be reduced.

  FIG. 5 shows still another example of the surplus heat recovery device 4. The surplus heat recovery device 4 is provided between the power generation facility 1 and the exhaust gas purification facility 3, and boiler feed water supplied to the economizer 6. Heat exchange is performed between at least a part of W ′ ′ and the exhaust gas G that is purified by the exhaust gas purification facility 3 and the exhaust gas G whose temperature is higher than that of the boiler feed water W ′ ′. The boiler feed water W ′ ′ is supplied to the economizer 6.

  That is, the surplus heat recovery device 4 shown in FIG. 5 includes a water branch line 51, a gas cooling device 52, a gas cooling device feed pump 53, a water return line 54, a water circulation line 55, a flow control valve 56, The first temperature detection controller 57 is provided, the upstream end of the water branch line 51 is connected to the boiler feed water supply line 28 and the downstream end of the water return line 54 is connected to the water branch line 51. And the boiler water supply line 28 downstream of the connection point of the boiler water supply line 28.

  The surplus heat recovery device 4 shown in FIG. 5 has the surplus heat recovery shown in FIG. 3 except that the connection location of the upstream end of the water branch line 51 and the connection location of the downstream end of the water return line 54 are changed. The structure is the same as that of the device 4, and the same reference numerals are given to the same parts and members as the excess heat recovery device 4 shown in FIG.

  The combined plant provided with the excess heat recovery device 4 shown in FIG. 5 can also recover the excess heat possessed by the exhaust gas G supplied from the exhaust gas purification facility 3 to the plant cultivation facility 2 to the power generation facility 1 side. While being able to improve efficiency, the fuel of the power generation facility 1 can be reduced, and the running cost can be reduced.

  In the above embodiment, the power generation facility 1 includes the boiler 5, the economizer 6, the air preheater 7, the dust collector 41, the induction fan 9, the exhaust pipe 10, the steam turbine 11, the generator 12, and the condenser. 13, although the deaerator 14, the condensate pump 15, the boiler feed pump 16, etc. are provided, the configuration of the power generation facility 1 is not limited to that according to the above embodiment, and at least the fuel is burned. As long as the combustion apparatus, the boiler 5, the steam turbine 11, the generator 12, the condenser 13, and the deaerator 14 are provided, any configuration may be adopted.

  In the above embodiment, a traveling stoker boiler that uses biomass as fuel is used as the boiler 5, but in other embodiments, the boiler 5 has other types of stepped stoker boilers, fluidized bed boilers, circulation A fluidized bed boiler, a heat generation boiler or the like may be used. However, when a waste heat boiler is used, a combustion apparatus such as a combustion furnace for burning fuel is incorporated in the power generation facility 1.

  Furthermore, in the above embodiment, biomass is used as the fuel. However, in other embodiments, fossil fuel such as oil, coal, natural gas, or waste such as municipal waste is used as the fuel. You may do it.

  Furthermore, in the above embodiment, the exhaust gas purification processing unit 32 of the exhaust gas purification facility 3 includes the dust collector 41, the neutralizer input unit 42, the activated carbon input unit 43, the gas reheater 44, and the carbon monoxide / ethylene removal device 45. However, the configuration of the exhaust gas purification processing unit 32 is not limited to that according to the above embodiment, and removes substances that impede plant growth from the exhaust gas G. As long as it can be purified and processed, it may be of any configuration.

  Furthermore, in the above embodiment, in the combined plant, the power generation facility 1 and the exhaust gas purification facility 3 are separately installed, and a part of the exhaust gas G discharged from the power generation facility 1 is extracted. Although the purification treatment was performed by the purification facility 3 and supplied to the plant cultivation facility 2, when all the exhaust gas G discharged from the power generation facility 1 is purified and supplied to the plant cultivation facility 2, the power generation facility 1 The exhaust gas purification system 3 may be incorporated into the exhaust gas discharge path of

  Furthermore, in the above embodiment, the excess heat recovery device 4 is provided with the flow control valve 56 at the connection point between the condensate return line 54 and the condensate circulation line 55, but in the other embodiments, the flow control valve 56 may be interposed in the condensate circulation line.

  Furthermore, in the above embodiment, the temperature of the exhaust gas G on the downstream side of the gas cooling device 52 is detected by the first temperature sensor 57a of the first temperature detection controller 57, and the detection from the first temperature sensor 57a Although the flow control valve 56 is controlled based on the signal, in another embodiment, although not shown, water for a boiler flowing into the gas cooling device 52 (condensed water W, makeup water W 'or The temperature of the boiler feed water W ′ ′) is detected by the first temperature sensor 57 a of the first temperature detection controller 57 so that the temperature does not cause corrosion by the acid drain of the gas cooling device 52. The flow control valve 56 may be controlled by a control signal from the controller 57.

1 Power generation equipment 2 Plant cultivation equipment 3 Exhaust gas purification equipment 4 Excess heat recovery device 5 Boiler 11 Steam turbine 12 Generator 13 condenser 13 Deaerator 31 Exhaust gas duct 32 Exhaust gas purification treatment Part 33: Exhaust gas supply ventilator 34: Exhaust gas circulation duct 35: Exhaust gas circulation damper 36: Exhaust gas flow control damper 51: Water branch line 52: Gas cooler 54: Water return line 55: Water circulation line 56: Flow control valve 57: 1 is a temperature detection controller 58 is a gas cooling ventilator G is exhaust gas S is steam S 'is exhaust steam W is condensate W' is makeup water W "is boiler feed water

Claims (12)

  Boiler that recovers heat from exhaust gas containing carbon dioxide generated by burning fuel, steam generator that recovers further heat from exhaust gas, steam turbine driven by boiler steam, power generation by driving steam turbine Power generation equipment including at least a generator, a condenser for condensing exhaust steam discharged from the steam turbine, and a deaerator for degassing the condensed water from the An exhaust gas duct that flows to a plant cultivation facility, and an exhaust gas purification facility that has an exhaust gas purification treatment unit that purifies exhaust gas that flows in the exhaust gas duct, and a power plant that generates power between the power generation facility and the exhaust gas purification facility. Heat exchange is performed between at least part of the boiler water used in the facility and the exhaust gas that has been purified by the exhaust gas purification processor and has a temperature higher than that of the boiler water. Of water use by heating with excess heat of the exhaust gas, combined plant, characterized in that a surplus heat recovery system for returning the water for the heated boiler power plant.   The surplus heat recovery apparatus is branched to a water supply line through which water for a boiler flows, and is purified by a water branch line that branches at least a part of water for a boiler flowing through the water supply line, and an exhaust gas purification processing unit The boiler water supplied from the water branch line is installed in the exhaust gas duct through which the treated exhaust gas flows, and the boiler water is purified and heat-exchanged with the exhaust gas whose temperature is higher than that of the boiler water. A gas cooler that heats with exhaust gas and cools the exhaust gas with boiler water, and boiler water heated by the gas cooler in a water supply line on the downstream side of the connection point between the water supply line and the water branch line The combined plant according to claim 1, further comprising a return water return line.   A water circulation line is provided between the water branch line of the surplus heat recovery device and the water return line to return part of the boiler water heated by the gas cooling device and flowing through the water return line to the water branch line. The complex plant according to claim 2, wherein   The surplus heat recovery system comprises a flow control valve for controlling the flow rate of boiler water which is heated by the gas cooling device and returned from the water circulation line to the water branch line, and purification treatment flowing in the exhaust gas duct downstream of the gas cooling device A temperature detection controller for detecting the temperature of the discharged exhaust gas or the temperature of water for the boiler flowing into the gas cooling device to control the flow control valve, the flow control valve being a gas cooling device The complex plant according to claim 3, wherein the combined plant is controlled based on a temperature detected from the temperature detection controller so that the temperature does not cause corrosion due to acidic drain.   The combined plant according to claim 4, wherein the flow rate control valve is provided at a connection point between a water return line through which boiler water flows and a water circulation line or a water circulation line.   The water for the boiler may be condensed water discharged from the condenser, or makeup water supplied to the deaerator, or boiler water supplied to the economizer. The complex plant in any one of -5.   The water supply line includes a condensed water supply line that supplies condensed water discharged from a condenser to a deaerator, a makeup water supply line that supplies makeup water to a deaerator, and a deaerator to an economizer The combined plant according to claim 2, further comprising: a boiler water supply line for supplying boiler water to the water supply line.   The exhaust gas duct on the downstream side of the gas cooling apparatus is connected with a gas cooling ventilator that supplies the air in the exhaust gas duct to lower the temperature of the purified exhaust gas to a predetermined temperature. The complex plant in any one of Claims 2-4.   The exhaust gas purification equipment is provided in an exhaust gas duct downstream of the exhaust gas purification processing section, and exhaust gas supply ventilator for attracting exhaust gas generated in the power generation equipment into the exhaust gas duct, and an exhaust gas duct upstream of the exhaust gas purification processing section. And an exhaust gas duct on the downstream side of the exhaust gas supply ventilator, and an exhaust gas circulation duct for returning the exhaust gas purified by the exhaust gas purification processing unit to the exhaust gas duct on the upstream side of the exhaust gas purification processing unit, and the exhaust gas circulation duct and the purification process And an exhaust gas flow control damper for controlling the flow rate of the exhaust gas supplied to the plant cultivation facility, which is interposed in the exhaust gas duct downstream of the connection part with the exhaust gas duct through which the exhaust gas flows. The complex plant according to claim 1.   The combined plant according to claim 1, wherein the fuel is biomass fuel.   Boiler that recovers heat from exhaust gas containing carbon dioxide generated by burning fuel, steam generator that recovers further heat from exhaust gas, steam turbine driven by boiler steam, power generation by driving steam turbine Power generation equipment including at least a generator, a condenser for condensing exhaust steam discharged from the steam turbine, and a deaerator for degassing the condensed water from the An exhaust gas duct flowing to a plant cultivation facility and an exhaust gas purification facility having an exhaust gas purification processing section for purifying exhaust gas flowing in the exhaust gas duct, and a surplus heat recovery method for a combined plant, which is used in a power generation facility The process of withdrawing at least a portion of the water for the boiler, the water for the withdrawn boiler and the exhaust gas purification processing unit, the exhaust gas having a temperature higher than that of the water for the boiler being purified And heat-exchanged the boiler water with excess heat of the exhaust gas, and returning the boiler water heated by the excess heat of the exhaust gas to the power generation facility. Surplus heat recovery method.   In the step of returning the boiler water heated by the excess heat of the exhaust gas to the power generation facility, the method further includes the step of returning a part of the heated boiler water to the boiler water before heating by the excess heat of the exhaust gas. The surplus heat recovery method for a complex plant according to claim 11.