JP2011257121A - Thermal storage system and hot water supply system equipped with the thermal storage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal storage system which can effectively use heat stored at a relatively low temperature of about 150-450°C.SOLUTION: In the thermal storage system 1 which is connected to a combustion system 1 accompanied by an exhaust gas at a given temperature of a 150-400°C band to effectively use exhaust heat from the combustion system 1, the thermal storage system is composed mainly of: a heat collection furnace 20 which is connected to an exhaust gas line of the combustion system 1 to catch heat of the exhaust gas from the combustion system; a thermal storage furnace 10 for storing heat from the heat collection furnace 20; and a heat transport circuit 30.

Description

The present invention relates to a heat storage system. More specifically, the present invention relates to a heat storage system that stores and effectively utilizes gas (exhaust heat) accompanied by heat from a combustion system such as a boiler.
The present invention further relates to a hot water supply system including the heat storage system.

  In recent years, interest in the effective use of energy has increased, and cogeneration systems and trigeneration systems have been developed as new energy supply systems that use exhaust heat from internal combustion engines, external combustion engines, etc. to extract power, heat, and cold energy to increase overall energy efficiency. Technologies for the system have been proposed. Tri-generation means an energy supply system that effectively uses carbon dioxide generated in addition to heat and electricity produced from a heat source for cogeneration (= electric heat combined use) in greenhouse cultivation and the like. It is a coined word. In recent years, the Kyoto Protocol has come into effect.

  For example, Patent Document 1 discloses a technique relating to a cogeneration system in which hot water in a hot water storage tank having a temperature higher than a set temperature is effectively used when hot water is filled in a bathtub, and the temperature is adjusted by pouring cold water. As a waste heat utilization system that effectively reduces gas replenishment and improves energy saving, a heat source unit, a cooling water pump that circulates cooling water that cools the heat source unit, and an appropriate temperature for the cooling water A waste heat recovery heat exchanger that cools the waste heat recovery heat exchanger, and a waste heat recovery pump that circulates waste heat recovery water that recovers waste heat using the cooling water as a heat source in the waste heat recovery heat exchanger, A cogeneration system comprising a hot water storage tank for storing exhaust heat recovery water from the cogeneration unit, and a recuperation boiler that replenishes the bath, and a waste heat utilization unit. In the system, in the hot water filling of the bathtub, supply means for supplying hot water in the hot water storage tank or supplying unheated water that is not heated from a predetermined water supply line, detection means for detecting the temperature and water level in the bathtub, and There has been proposed an exhaust heat utilization system provided with a control means for adjusting a hot water filling temperature to a bathtub using the detection means and the supply means.

  Patent Document 2 discloses a hot water boiler that uses hot exhaust gas as a heat source, a hot water boiler that uses hot exhaust gas as a heat source, and a cogeneration system that enables heating and cooling and hot water supply by combining a hot water boiler that uses hot exhaust gas and an absorption chiller / heater. A hot water heater that uses hot water as a heat source, an absorber, a low-temperature regenerator, a high-temperature regenerator, a condenser, an evaporator, and a solution channel and a refrigerant channel that connect these devices, and hot water and fuel from the hot water boiler A hot water supply heat exchanger connected to the steam section of the high-temperature regenerator, and the hot water supply heat exchanger is provided with a hot water supply heat absorption type absorption chiller / heater having a heat source as a heat source. A system having a flow path for passing hot water has been proposed.

  On the other hand, as a power generation system using waste heat, in Patent Document 3, the power generation method of waste heat utilization electric power is a method in which hot water obtained by exhaust heat recovery means for recovering thermal energy of exhaust gas as hot water is used in a plurality of stages of flashers. When the steam obtained by the flasher is supplied to the steam turbine to drive the generator, the wet steam discharged from the steam turbine is supplied to the condenser and returned to the water. An adsorption chiller is used as a means for cooling the discharged cooling water and supplying it to the condenser, and as a heat source water for heating the adsorbent of the adsorption chiller, the final stage of the plurality of stages of flashers. A method for obtaining electric power using hot water discharged from the flasher is described.

  JP 2003-120322 A   JP 2002-372337 A   JP 2010-106764 A

  However, the conventional cogeneration systems disclosed in Patent Documents 1 and 2 are configured from devices premised on the cogeneration system in advance, and it is difficult to effectively use the exhaust heat of the existing combustion system.

  The technique described in Patent Document 3 is intended for large-scale combustion systems that generate a large amount of exhaust heat, and the combustion efficiency of various combustion systems such as small incinerators, boilers, and oil refineries is generally It is said that it is said that it is 70-80%, and the present condition is that the technique which utilizes effectively the gas exhausted in the atmosphere of the temperature of about 150 to 400 degreeC generated from the discharge port of a combustion system is not established.

  Accordingly, an object of the present invention is to provide a heat storage system that can effectively use heat stored at a relatively low temperature of about 150 ° C. to 450 ° C.

  Another object of the present invention is to provide a hot water supply system connected to an existing hot water supply boiler using the heat storage system.

The present invention has been made in view of the above problems, and relates to the following items.
(1) A heat storage system for effectively using the exhaust heat by connecting to a combustion system with exhaust gas having a predetermined temperature in a range of 150 to 400 ° C., and connecting the exhaust gas line of the combustion system to exhaust gas from the combustion system A heat storage furnace comprising: a heat collection furnace that captures the heat of the heat collection furnace; a heat storage furnace that stores heat from the heat collection furnace; and a heat transport circuit that transports the heat captured by the heat collection furnace. system.

(2) The heat storage system according to (1), wherein the heat collecting furnace is made of diatomaceous earth formed at a density that does not impair the flow rate of the exhaust gas.

(3) The regenerative furnace includes a closed gas circulation passage having a gas inlet to be introduced into the regenerator, an outlet for discharging a non-combustible gas having a high expansion coefficient that has been given heat by the regenerator, and the gas. A piston motor that is provided on the gas outlet side of the circulation channel and converts the pressing force of the expanded gas into a rotational force, a generator that generates electric power based on the rotational motion from the piston motor, and the gas from the piston motor The heat storage system according to (1) or (2), comprising a power generation system including a cooling device for cooling.

(4) The heat storage system according to (3), further including a speed increasing device that increases a rotational speed converted by the piston motor between the piston motor and the generator.

(5) A cogeneration system including the heat storage system according to any one of (1) to (4) and a combustion system with exhaust gas having a predetermined temperature in a range of 150 to 400 ° C.

(6) A heat storage system for connecting to a feed water boiler with exhaust gas having a predetermined temperature in a range of 150 to 400 ° C. to increase fuel consumption of the boiler, connected to the exhaust gas line of the boiler, A heat collecting furnace for capturing the heat of exhaust gas, a heat storage furnace for storing heat from the heat collecting furnace, a heat transport circuit for transporting the heat captured by the heat collecting furnace, a water supply port for supplying water, A water supply tank having a drain outlet for supplying warm water to the boiler, wherein the water supply tank and the heat storage furnace are configured to transfer the heat stored in the heat storage furnace to the water supply tank. A heat storage system having a transport circuit and supplying water heated by the heat from the heat storage furnace via the second heat transport circuit to the boiler.

(7) The regenerative furnace includes a closed-system gas circulation flow path having a gas inlet to be introduced into the regenerator, an outlet for discharging a non-combustible gas having a high expansion coefficient that has been given heat by the regenerator, and the gas A piston motor that is provided on the gas outlet side of the circulation channel and converts the pressing force of the expanded gas into a rotational force, a generator that generates electric power based on the rotational motion from the piston motor, and the gas from the piston motor A heat storage system according to (6), comprising a power generation system including a cooling device for cooling.

(8) A water supply system including a water supply boiler with exhaust gas having a predetermined temperature in a 150 to 400 ° C. band, and the heat storage system according to (6) or (7).

According to the heat storage system of the present invention, heat can be easily stored with an existing combustion system, and exhaust heat can be effectively utilized.
Further, when the heat storage system of the present invention and the combustion system are combined, a cogeneration system can be easily constructed.
Furthermore, when the heat storage system of the present invention is combined with a boiler for hot water supply, it becomes possible to improve the fuel efficiency of gas, heavy oil and the like.

  Drawing which shows schematic structure of the thermal storage system of this invention.   Drawing which shows the example of use of the thermal storage system of this invention.   Drawing which shows an example which provided the electric power generation system in the thermal storage system of this invention.   The figure which shows an example which applied the electrical storage system of this invention to the hot-water supply system.   The drawing which shows an example which applied the electrical storage system of this invention to the oilification plant.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
First, the outline of the present invention will be described with reference to FIG.

  As shown in FIG. 1, the heat storage system of the present invention is a heat storage system that is connected to the combustion system 1 with exhaust gas having a predetermined temperature in the 150 to 400 ° C. band to effectively use the exhaust heat from the combustion system 1. The heat storage system 1 is connected to the exhaust gas line of the combustion system 1 to capture the heat of the exhaust gas from the combustion system, the heat storage furnace 10 to store the heat from the heat collection furnace 20, and heat transport. It is mainly composed of the circulation path 30.

  The combustion system 1 with exhaust gas having a predetermined temperature in the 150 to 400 ° C. band can be a combustion device, a combustion furnace, a reaction device, a boiler, or the like that is generally used in a factory, and is not particularly limited. The combustion system of the present invention may generate exhaust gas (hereinafter referred to as exhaust heat) at a predetermined temperature continuously for 24 hours, but the heat storage system of the present invention is applied to a combustion system that exhausts heat intermittently. This is preferable because stable heat can be captured and stored.

  The heat storage system according to the present invention captures heat captured by the heat collecting furnace 20 continuously or intermittently from the exhaust heat exhausted from the combustion system 1 to the heat storage furnace 10 via the heat transport circuit 30. This system stores heat.

  The heat storage furnace 10 is not particularly limited as long as it is a material that can stably store heat in the 150 to 400 ° C. band. For example, as described in the solar heat storage system in the solar heat storage system previously proposed by the present inventors (Japanese Patent Application No. 2001-134327, applicant Yozo Kato et al.), The heat storage furnace 10 is a heat insulating material that covers the heat storage oil and its surroundings. It can consist of.

  The heat collecting furnace 20 is preferably a material that can capture only heat without impairing the flow rate of the exhaust gas from the combustion system 1. According to the study of the present inventor as such a material, it is preferable to use diatomaceous earth from the viewpoint that it stably exhibits an effect as a heat insulating material for a furnace material, is lightweight, easily available, and easy to process.

The heat transport circuit 30 in the present invention is a heat exchange flow path that receives the heat captured by the heat collecting furnace 20 and transports it to the heat storage furnace 10, and medium oil is accommodated in the flow path. As such medium oil, the specific gravity described in the solar heat storage system previously proposed by the present inventors (Japanese Patent Application 2001-134327, applicant Yozo Kato et al.) Is 1 to 2.5 g / cm ³ . Medium oil is preferred. However, it is not particularly limited as long as it is a medium oil having similar actions and effects.

  The heat storage system of the present invention configured as described above can be easily combined with the existing combustion system 1 and can efficiently capture the heat exhausted as exhaust gas and store it in the heat storage furnace. Become. The heat stored in the regenerative furnace 10 can be applied to various applications as shown in FIG. 2, for example, as is well known in the art. That is, the stored heat can be used as hot water for hot water supply, floor heating, greenhouse heating, etc. by exchanging heat with water in addition to power generation, and can also be recycled as a heat source for factories and the like.

  Further, by combining with an existing combustion system, the heat storage system of the present invention can easily construct a cogeneration system.

  Next, a specific embodiment of the present invention will be described with reference to FIG. The example shown in FIG. 3 shows the example which combined the thermal storage system of this invention with the unique electric power generation system.

  The heat storage system shown in FIG. 3 includes a heat storage furnace 10 that stores heat from the heat collection furnace 20, a gas inlet 12in that is introduced into the heat storage furnace 10, and an outlet 12out that discharges the gas given heat in the heat storage furnace. A closed-system gas circulation passage 12, a gas outlet 12 out side of the gas circulation passage 12, and a piston motor 13 a that converts the pressing force of the expanded gas into a rotational force; It is mainly comprised from the generator 13b which produces electric power based on rotational motion, and the cooling device 14 which cools the gas from the piston motor 13a, Preferably it is between the piston motor 13a and the generator 13b, and the speed increasing device 13c. Is provided.

  In this embodiment, a power generation system is provided as the secondary side, but in addition to the power generation system, it is also possible to use heat stored by a conventionally known usage method.

  In the present invention, as shown in FIG. 3, a heat storage furnace 10 that stores heat from a heat collecting furnace 20 that collects exhaust heat discharged from the combustion system 1 as a heat source via a heat transport circulation path 30, and a heat storage furnace 10. A closed-system gas circulation passage 12 having a gas inlet 12in to be introduced into the inside and an outlet 12out for discharging the gas applied with heat in the regenerative furnace 10 is provided, and the power generation system is provided on the gas outlet 12out side of the circulation passage 12 13 is provided, and a cooling device 14 for cooling the gas is provided on the inlet 12in side.

  A gas having a high expansion coefficient, for example, alternative chlorofluorocarbon, is hermetically sealed in the circulation flow path 12, and the gas heated in the regenerative furnace 10 expands by heat and enters the power generation system 13 and then the cooling device 14. After cooling, the heat storage furnace 10 is reentered and heat is applied.

  The power generation system 13 includes a piston motor 13a and a generator 13b, preferably a speed increasing device 13c provided between the piston motor 13a and the generator 13b.

  The piston motor 13a is a device that presses the piston with gas thermally expanded by the heat storage furnace 10 and converts it into rotational energy. In the present invention, the piston motor 13a is one-way to the generator 13b side by an expansion valve (not shown). Pressure is constantly applied. And the piston motor 13a has the structure which converts this pressure into rotational energy, and sends it to the generator 13b side.

  The speed increasing device 13c is a device that increases the rotational energy (number of rotations) converted by the piston motor 13a. For example, the speed increasing device 13c increases the rotational energy input at 1000 rpm to 3000 rpm and inputs the rotational energy to the generator 13b. .

  The generator 13b is a generator that generates electric power based on the rotational energy accelerated by the piston motor 13a, preferably the speed increasing device 13c.

  By comprising in this way, it becomes possible for the gas expanded by heat provision on the outlet 12out side of the circulation channel 12 to constantly press the piston motor 13a and convert it into rotational energy to generate electric power. Therefore, it is possible to generate power very efficiently by providing the speed increasing device 13c. Therefore, it is possible to efficiently generate the heat (exhaust heat of combustion hair) stored in the heat storage system of the present invention.

  According to the study by the present inventors, the amount of power generation depends on the capacity of the piston motor, but when a commercially available piston motor is used, it depends on the amount of heat stored in the regenerative furnace 10 and is from several tens KW / h to several thousand KW / h. It was found that power can be generated efficiently to the extent.

  The thermally expanded gas is cooled by the cooling device 14, enters the regenerative furnace 10 again, and expands by applying heat.

  In the power generation in the heat storage system having such a configuration, first, gas is passed through the heat storage furnace 10 to apply heat stored in the heat storage furnace 10 to the gas having a high expansion coefficient. Thereby, gas with a high expansion coefficient expand | swells by heat provision. Next, the gas expanded by applying heat is continuously applied to the piston motor 13a to convert the pressure due to expansion into rotational energy. Preferably, the converted rotational energy is increased by the speed increasing device 13c and applied to the generator 13b to generate power. The heat-applied gas is cooled and reapplied.

  With this configuration, the stored thermal energy is continuously applied to a gas with a high expansion coefficient and expanded, and this is converted into rotational energy for power generation. Power generation can be performed.

  Next, the example which applied the thermal storage system of this invention to the hot water supply system based on FIG. 4 is shown. In the embodiment shown in FIG. 4, in the embodiment shown in FIG. 1, the point that the combustion system 1 is specified as a hot water supply boiler and the hot water supply tank 40 are provided, and the water in the hot water supply tank 40 is transferred to the heat from the regenerator 10. 1 has the same configuration as that of the embodiment shown in FIG. 1 except that the heating is performed via the heat transport circulation channel 40. Therefore, the same members are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, it is also within the scope of the present invention to provide, for example, the power generation system shown in FIG. 3 in the embodiment shown in FIG.

  The water supply boiler 1 ′ generally heats normal temperature water using heavy oil, gas, or the like as fuel and supplies it to hot water. The heat storage system of the present embodiment is a system that improves the fuel consumption of the feed water boiler 1 'by connecting to the exhaust gas line of such a feed water boiler 1'. The heat collection furnace 20, the heat storage furnace 10, and heat transport It is mainly comprised from the circulation path 30 and the water supply tank 40 for supplying water to the water supply boiler 1 '.

  The heat storage system according to the present embodiment shown in FIG. 4 stores the exhaust heat from the water supply boiler 1 ′ in the heat storage furnace 10 as in the heat storage system shown in FIG. 1. And in the heat storage system which concerns on this embodiment, the water supply tank 40 has the water supply port 41 and the waste_water | drain port 42, and the water supply tank 40 and the heat storage furnace 10 are the water supply tank 40 which stored the heat stored in the heat storage furnace 10. A second heat transport circuit 50 for transporting to

  Then, the low-temperature water supplied from the water supply port 41 is heated by the heat stored in the water supply tank 40 and stored in the heat storage furnace 10 via the second heat transport circuit 50. Yes. The heat storage system of this embodiment supplies the warm water heated in this way to the water supply boiler 1 ′ from the drain outlet 42.

  With this configuration, the water supplied to the water supply tank 40 is always heated by ΔT by the heat stored in the regenerative furnace 10 via the second heat transport circuit 50. Therefore, when combined with the heat storage system of the present invention and a conventional water supply boiler, the energy corresponding to ΔT (× supply amount) is reduced compared to a conventional water supply boiler that heats water supplied directly from the water supply port. It becomes possible.

  Similar to the embodiment shown in FIG. 1, by combining with an existing boiler for water supply, the heat storage system of the present invention can construct a hot water supply system that can easily improve fuel efficiency.

  Next, an example in which the heat storage system of the present invention is applied to an oil plant is shown based on FIG. This embodiment shows an example in which the heat storage system of the present invention is applied to a plant that generates gas accompanying thermal decomposition, such as an oil plant, a carbon plant, and an oil carbon plant.

  As shown in FIG. 5, the raw material input from the raw material input port IN is used as a carrier gas to supply superheated steam or the like to the pyrolysis furnace 1 ″, and is pyrolyzed by the pyrolysis furnace 1 ″ as a heat source, and the pyrolysis gas It is a configuration of a general oiling plant (carbonization plant) that removes impurities therein by a purification device such as a scrubber S and performs oilification (or carbonization).

  In the present invention, the heat from the pyrolysis furnace 1 ″ is collected by the heat collecting furnace 20 and stored in the heat accumulating furnace 10 through the heat transport circuit 20. The gas passing through the heat collecting furnace 20 is conventionally used. As in the case of technology, it passes through a scrubber and the like and proceeds to the subsequent oil production process.

  In the present invention, the heat generated in the thermal decomposition is stored in the regenerative furnace 10, but in addition to using the heat stored in the power generation and the like as in the embodiment shown in FIG. 1 and the embodiment shown in FIG. It can also be effectively used as a heat source for generating heat.

  The heat storage system of the present invention configured as described above can be easily combined with the existing combustion system 1 and can efficiently capture the heat exhausted as exhaust gas and store it in the heat storage furnace. Become. The heat stored in the regenerative furnace 10 can be applied to various uses as shown in FIG. 2, for example, as is well known in the art. That is, the stored heat can be used as hot water for hot water supply, floor heating, greenhouse heating, etc. by exchanging heat with water in addition to power generation, and can also be recycled as a heat source for factories and the like.

  Further, by combining with an existing combustion system, the heat storage system of the present invention can easily construct a cogeneration system.

  When the heat storage system of the present invention is combined with a water supply boiler, the water supplied to the water supply tank is always heated by ΔT by the heat stored in the heat storage furnace via the second heat transport circuit. Therefore, when combined with the heat storage system of the present invention and a conventional water supply boiler, the energy corresponding to ΔT (× supply amount) is reduced compared to a conventional water supply boiler that heats water supplied directly from the water supply port. It becomes possible.

  Similarly, by combining with an existing water supply boiler, the heat storage system of the present invention can construct a hot water supply system that can easily improve fuel efficiency.

1 Combustion system (boiler)
DESCRIPTION OF SYMBOLS 10 Heat storage furnace 12 Gas circulation flow path 13a Piston motor 13b Generator 13c Speed increaser 14 Cooling device 20 Heat collecting furnace 30 Heat transport circuit 40 Water supply tank 50 Second heat transport circuit

Claims (8)

A heat storage system for effectively using the exhaust heat by connecting to a combustion system with exhaust gas having a predetermined temperature in a 150 to 400 ° C. band,
A heat collecting furnace connected to the exhaust gas line of the combustion system to capture the heat of the exhaust gas from the combustion system;
A heat storage furnace for storing heat from the heat collecting furnace;
A heat transport circuit for transporting heat captured by the heat collecting furnace;
A heat storage system characterized by comprising:   The said heat collection furnace is comprised from the diatomaceous earth formed with the density which does not impair the flow volume of the said waste gas, The heat storage system of Claim 1 characterized by the above-mentioned.   The regenerative furnace includes a closed gas circulation passage having an inlet for gas introduced into the regenerative furnace, and an outlet for discharging incombustible gas having a high expansion coefficient that has been imparted with heat in the regenerator, and the gas circulation passage. A piston motor for converting the pressing force of the expanded gas into rotational force, a generator for generating electric power based on the rotational motion from the piston motor, and cooling for cooling the gas from the piston motor The heat storage system according to claim 1, further comprising a power generation system including the apparatus.   The heat storage system according to claim 3, further comprising a speed increasing device that increases a rotational speed converted by the piston motor between the piston motor and the generator.   A cogeneration system comprising the heat storage system according to any one of claims 1 to 4 and a combustion system with exhaust gas having a predetermined temperature in a 150 to 400 ° C band. A heat storage system for connecting to a feed water boiler with exhaust gas having a predetermined temperature in a 150 to 400 ° C. band to increase fuel consumption of the boiler,
A heat collecting furnace connected to an exhaust gas line of the boiler to capture heat of exhaust gas from the combustion system;
A heat storage furnace for storing heat from the heat collecting furnace;
A heat transport circuit for transporting heat captured by the heat collecting furnace;
A water supply tank having a water supply port for supplying water and a drain port for supplying warmed water to the boiler,
The water supply tank and the regenerator have a second heat transport circuit that transports heat stored in the heat accumulator to the water tank, and the second heat transport circuit is heated by heat from the heat storage furnace. The heat storage system characterized by supplying the said water heated via the said boiler.   The regenerative furnace includes a closed gas circulation passage having an inlet for gas introduced into the regenerative furnace, and an outlet for discharging incombustible gas having a high expansion coefficient that has been imparted with heat in the regenerator, and the gas circulation passage. A piston motor for converting the pressing force of the expanded gas into rotational force, a generator for generating electric power based on the rotational motion from the piston motor, and cooling for cooling the gas from the piston motor The heat storage system according to claim 6, further comprising a power generation system including a device. A feed water boiler with exhaust gas at a predetermined temperature in the 150 to 400 ° C. band;
The heat storage system according to claim 6 or 7,
A water supply system composed of

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