JP2016063755A - Plant cultivation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plant cultivation system which can suppress reduction in a ratio of heat quantity which can be recovered with respect to heat quantity generated in a gas turbine or the like.SOLUTION: A plant cultivation system comprises: a power generator 1 which uses an internal combustion engine as a power source; an exhaust heat recovery device 2 which recovers heat from exhaust gas generated in the power generator 1; and a denitrification device 10 which removes nitrogen oxide in the exhaust gas, in which the system supplies carbon dioxide contained in exhaust gas to plants to raise the plants. The exhaust gas is supplied from the exhaust heat recovery device 2 to the plants via the denitrification device 10, the denitrification device 10 is a dry absorbent formed by impregnating KOH into a base material made of gypsum and active carbon powder, and the denitrification device 10 has a dilution chamber 7 as condensation suppressing means for suppressing internal condensation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to plant cultivation of a trigeneration system.

  In recent years, plant cultivation of a “trigeneration system” that effectively uses CO2 (carbon dioxide) in addition to electricity and heat generated in a cogeneration (cogeneration) system has been experimentally conducted.

  In an actual system, the exhaust gas of a gas turbine used as a generator in a cogeneration system contains nitrogen oxides that hinder plant growth in addition to carbon dioxide, which is useful for plant cultivation. A plant cultivation system incorporating a denitration device for removing oxides has been proposed (see, for example, Patent Document 1).

  The method for removing nitrogen oxides of this plant cultivation system is an ammonia catalytic reduction method, and requires a temperature of 170 ° C. or higher at which ammonia is consumed and the catalyst functions. It has a configuration arranged between them.

Japanese Patent No. 5073264

  In such a conventional plant cultivation system, the heat of the exhaust gas generated in the gas turbine is partially used in the denitration device and then recovered in the exhaust heat recovery device. On the other hand, there has been a problem that the ratio of the amount of heat that can be recovered becomes low.

  Then, this invention solves the said conventional subject, and it aims at providing the plant cultivation system which can suppress that the ratio of the calorie | heat amount which can be collect | recovered with respect to the calorie | heat amount generated with a gas turbine becomes low.

  In order to achieve this object, the present invention provides a generator using an internal combustion engine as a power source, an exhaust heat recovery device that recovers heat from the exhaust gas generated by the generator, and nitrogen in the exhaust gas. A denitration device that removes oxides, supplying carbon dioxide contained in the exhaust gas to a plant and growing the plant, wherein the exhaust gas is supplied from the exhaust heat recovery device to the plant The denitration device is supplied to the plant through a denitration device, and the denitration device is a dry absorbent obtained by impregnating a base material made of gypsum and activated carbon powder with KOH, and the denitration device has dew condensation suppression means for suppressing dew condensation inside The plant cultivation system is characterized by this, and the intended purpose is thereby achieved.

  According to the present invention, a dry absorbent is used for the denitration device, and the denitration device has a dew condensation suppressing means for suppressing dew condensation inside, so that the exhaust generated by the generator without using the denitration device. Since heat can be recovered from the gas, it is possible to obtain an effect of providing a plant cultivation system that can suppress a reduction in the ratio of the amount of heat that can be recovered to the amount of heat generated in the gas turbine.

  That is, since the dry absorbent can exhibit the nitrogen oxide removing function at room temperature, there is no need to arrange the denitration device between the gas turbine and the exhaust heat recovery device as in the conventional example, the gas turbine, the exhaust heat recovery device, It becomes possible to flow exhaust gas in the order of the denitration device.

  Therefore, since the heat of the exhaust gas immediately after it is generated by the gas turbine can be recovered by the exhaust heat recovery device, it is possible to suppress the ratio of the amount of heat that can be recovered with respect to the amount of heat generated by the gas turbine from the conventional example.

Whole block diagram of plant cultivation system of Embodiment 1 of the present invention 1 is an internal structure diagram of a denitration apparatus according to Embodiment 1 of the present invention. Side view of the denitration apparatus of Embodiment 2 of the present invention The perspective view of the denitration apparatus of Embodiment 3 of this invention

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is an overall configuration diagram of a plant cultivation system in the present invention. This system is a trigeneration system that supplies the cultivation room 14 with electricity generated by the generator 1, heat generated during power generation, and carbon dioxide.

  This system includes a generator 1, an exhaust heat recovery device 2, a recovery heat pipe 3, a return pipe 4, an outside air introduction pipe 5, an outside air introduction damper 6, a dilution chamber 7, a drain pipe 8, a filter 9, a denitration apparatus 10, and an inverter 11. A fan 12, a flow rate adjusting damper 13, a cultivation room 14, a CO2 meter 15, and a flow meter 16.

  First, heat is recovered from the exhaust gas generated by the generator 1 by the exhaust heat recovery device 2. In the exhaust heat recovery apparatus 2, heat exchange of exhaust gas and water is performed by a heat exchanger (not shown) to cool the exhaust gas and generate hot water.

  The generated warm water is supplied to the cultivation room 14 via the recovery heat pipe 3. The water whose temperature is reduced by supplying heat in the cultivation room 14 returns to the exhaust heat recovery device 2 via the return pipe 4 and becomes hot water again by the heat exchanger.

  The exhaust gas heat recovered by the exhaust heat recovery device 2 is removed from the nitrogen oxide in the exhaust gas by the denitration device 10 installed on the downstream side of the exhaust heat recovery device 2, and then carbon dioxide contained in the treated air is removed. Supply to the cultivation room 14.

  The flow rate and concentration of air containing carbon dioxide (hereinafter simply referred to as “carbon dioxide”) supplied to the cultivation room 14 are monitored by a flow meter 16 and a CO 2 meter 15, respectively. The flow rate of carbon dioxide is adjusted by changing either or both of the frequency of the inverter 11 that drives the fan 12 and the opening of the flow rate adjusting damper 13.

  The concentration of carbon dioxide is adjusted by introducing outside air into the exhaust gas, and the amount of outside air introduced into the dilution chamber 7 is adjusted by adjusting the opening of the outside air introducing damper 6 provided in the outside air introducing pipe 5. The exhaust gas and the outside air are mixed in the dilution chamber 7 and adjusted to a predetermined carbon dioxide concentration.

  In addition, when the carbon dioxide concentration and the flow rate for each operating condition can be grasped in advance, the CO2 meter 15 and the flow meter 16 are not necessarily installed.

  Here, the denitration apparatus 10 which is a feature of the present application will be described with reference to FIG.

  The denitration apparatus 10 stores a dry absorbent 21 in a housing. The dry absorbent 21 is obtained by impregnating a base material containing gypsum and activated carbon powder with KOH. Nitrogen oxides in the exhaust gas are adsorbed by the fine pores of the activated carbon, and are removed by changing the adsorbed nitrogen oxides into salts by a chemical reaction with KOH.

  In addition, although the flow of a wind is illustrated with the arrow, in order to enlarge the ventilation part (opening part) area as much as possible, the dry absorbent 21 is generally arranged in a pleat shape as shown in FIG. It is.

  This dry absorbent is normally used in a room temperature environment such as a tunnel, and the temperature reduction of exhaust gas in the denitration apparatus 10 does not cause a problem.

  However, when applied to the plant cultivation system of the present application, heat recovery is performed by a heat exchanger or the like in the exhaust heat recovery device 2, but the situation where the exhaust gas on the downstream side is still at room temperature or higher, for example, 70 ° C. or higher is also conceivable. .

  That is, since the dry absorbent is vulnerable to moisture, dew condensation occurs due to a decrease in the temperature of the exhaust gas in the denitration apparatus 10, and when the condensed water adheres to the dry absorbent, the adsorption of nitrogen oxides is hindered. There arises a new problem that the removal performance is lowered.

  In order to solve this problem, dew condensation suppression means, which is another feature of the present application, is required.

  Below, the specific example of a dew condensation suppression means is demonstrated.

  Since the dilution chamber 7 described above mixes exhaust gas and outside air to adjust the carbon dioxide concentration, the temperature and humidity of the exhaust gas after mixing is lowered, and includes the outside air introduction pipe 5 and the outside air introduction damper 6. Therefore, it also has a function of suppressing dew condensation in the denitration apparatus 10.

  That is, the high-temperature exhaust gas is cooled by the low-temperature outside air, so that dew condensation occurs in the dilution chamber 7 before flowing into the denitration apparatus 10.

  Condensed water generated from the exhaust gas cooled by the outside air is discharged out of the system through the drain pipe 8. A part of the condensed water remaining in the exhaust gas and transported together with the exhaust gas is removed by the filter 9.

  Thus, by reducing the temperature of the exhaust gas in the dilution chamber 7, dew condensation in the denitration apparatus 10 is suppressed, and the dry absorbent can be used in an environment higher than normal temperature.

(Embodiment 2)
FIG. 3 shows a configuration diagram of a denitration apparatus 10 as another embodiment of the dew condensation suppressing means. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The denitration apparatus 10 includes a recovery heat pipe 3 that circulates a part of the hot water generated by the exhaust heat recovery apparatus 2 on any or all of the side surface, top surface, and bottom surface of the casing as a heat retention device. Heat is supplied to the denitration apparatus 10 and the water whose temperature has dropped is returned to the exhaust heat recovery apparatus 2 via the return pipe 4.

  As a result, the temperature of the exhaust gas flowing into the denitration apparatus 10 can be heated to the same level or higher, and even if the temperature of the exhaust gas flowing into the denitration apparatus 10 is equal to or higher than normal temperature, the exhaust gas temperature in the denitration apparatus 10 is prevented from lowering and dew condensation occurs. It is possible to suppress the performance deterioration of the dry absorbent 21 due to the occurrence of the above.

  In FIG. 3, hot water is supplied from the recovery heat pipe 3 to the denitration apparatus 10, but when the water in the return pipe 4 has a temperature higher than room temperature, water is supplied from the return pipe 4 to the denitration apparatus 10. In addition, it is possible to keep the required heat, and it is possible to further suppress the reduction in the proportion of the amount of heat that can be recovered.

(Embodiment 3)
FIG. 4 shows a perspective view of a denitration apparatus 10 as still another embodiment of the dew condensation suppressing means. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The denitration device 10 includes a heat insulating material 31 as a heat insulating device on all of the outer peripheral portions (side surface, top surface, and bottom surface) of the housing. When the temperature difference between the exhaust gas and the outside air is small, the heat insulating material 31 may be provided only on one of the outer peripheral portions (side surface, top surface, bottom surface) of the housing.

  The heat insulating material is made of, for example, board type glass wool, and has a thickness of about 50 to 100 mm and a density of about 20 to 50 kg / m 3.

  Thereby, the transmission (release) of heat to the periphery of the denitration apparatus 10 can be prevented, the exhaust gas temperature in the denitration apparatus 10 can be prevented from lowering, and as a result, the performance degradation of the dry absorbent 21 due to the occurrence of condensation can be suppressed. .

  Note that the dew condensation suppressing means of the above-described first to third embodiments can be used alone or in combination.

  Since the plant cultivation system concerning this invention can suppress that the ratio of the calorie | heat amount which can be collect | recovered with an exhaust heat recovery apparatus becomes low, it is useful as plant cultivation etc. of a "trigeneration system".

DESCRIPTION OF SYMBOLS 1 Generator 2 Waste heat recovery device 3 Recovery heat piping 4 Return piping 5 Outside air introduction piping 6 Damper for outside air introduction 7 Dilution chamber 8 Drain piping 9 Filter 10 Denitration device 11 Inverter 12 Fan 13 Damper for flow adjustment 14 Cultivation room 15 CO2 meter 16 Flow meter 21 Dry absorbent 31 Heat insulation material

Claims (6)

A generator powered by an internal combustion engine;
An exhaust heat recovery device that recovers heat from the exhaust gas generated by the generator;
A denitration device for removing nitrogen oxides in the exhaust gas,
A plant cultivation system for supplying carbon dioxide contained in the exhaust gas to a plant and growing the plant,
The exhaust gas is supplied from the exhaust heat recovery device to the plant via the denitration device,
The denitration device is a dry absorbent obtained by impregnating a base material made of gypsum and activated carbon powder with KOH,
The denitration apparatus has a dew condensation suppressing means for suppressing dew condensation inside. 2. The plant cultivation system according to claim 1, wherein dew condensation suppression means is provided on the denitration apparatus and / or upstream thereof. The plant cultivation system according to claim 2, wherein the dew condensation suppressing means is a dilution chamber provided between the exhaust heat recovery device and the denitration device for diluting the exhaust gas with outside air. The plant cultivation system according to claim 2 or 3, wherein the dew condensation suppressing means is a heat retaining device for retaining the denitration device. The plant cultivation system according to claim 4, wherein the heat recovered by the exhaust heat recovery device is used as a heat source of the heat retention device. The plant cultivation system according to any one of claims 2 to 5, wherein the dew condensation suppressing means is a heat insulating device that insulates the outer shell of the denitration device.

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