JPH01296047A - Hot water supply device utilizing exhaust gas from engine - Google Patents

Abstract

PURPOSE:To utilize the latent heat of evaporation of exhaust gas by adjusting hot water obtained in a latent heat recovery unit to a suitable temperature in a hot water heat exchanger disposed in the bottom of the latent heat recovery unit, and further heating the same directly or in a coolant heat exchanger. CONSTITUTION:A latent heat recovery unit 8 has in its upper part a feed water pipe 9 having a spray head 9a and a discharge pipe 1, a filler layer 11 directly under the feed water pipe 9 in its middle section, and in its bottom a table 12 having a slope as a delivery section 12a to deliver hot water to the next process, an exhaust gas pipe 13 and a hot water heat exchanger 14. The hot water obtained by recoverying the heat quantity possessed by the exhaust gas to about the atmospheric temperature is converted into clean hot water in a hot water heat exchanger 14, and it is further heated as needed. The hot water heat exchanger 14 is set in the bottom of the latent heat recovery unit 8.

Description

[Detailed Description of the Invention] [Industrial Application Field] Recently, a water heater has appeared as a type of combined heat and power generation device that generates electricity using the driving force of a gas engine and uses the exhaust gas from the same to generate high-temperature water. are doing.

The present invention provides a hot water heater using exhaust gas,
This invention relates to improvements in water heaters suitable for drinking water.

[Prior Art] For example, as shown in FIG. 2, a conventional combined heat and power system includes a cooling water circulation path 1a, a branch circulation path 1b, and an exhaust pipe I.
A gas engine equipped with 1.C. AC generator 2. Cooling water heat exchanger 3. An exhaust gas heat exchanger 4, a hot water heat exchanger 5, and a hot water pump 5° were arranged. In addition, 6
7 is an exhaust gas discharge pipe, and 7 is a hot water supply pipe.

With the above configuration, power is generated by the alternator 2 when the gas engine 1 is driven, and tap water is heated in the cooling water heat exchanger 3 using the hot water after cooling the high-temperature parts of the engine 1. This is further supplied to the exhaust gas heat exchanger 4, where it is heated by the exhaust gas supplied from the exhaust pipe 1c, and the resulting high temperature water is used as a heat source to be heated to a drinkable high temperature through the hot water heat exchanger 5. It was converted into water and used for hot water supply. The hot water that has become a heat source in the hot water heat exchanger 5 is transferred to the cooling water heat exchanger 3 via a hot water pump 5°.
The water was reused as water supply.

[Problems to be Solved by the Invention] As described above, conventional exhaust gas heat exchangers, which are gas/water indirect heat exchangers, are used as a method of recovering heat from the high-calorie exhaust gas generated by the gas engine 1. 4 was the main focus.

For this reason, if the supply water (20°C) is suddenly put into the exhaust gas heat exchanger 4 for heat recovery, the exhaust pipe 6 of the heat exchanger will suffer low temperature corrosion due to condensation of the gas with a large temperature difference. To avoid.

After being preheated to a temperature of about 50°C in the cooling water heat exchanger 3, the water is further passed through the exhaust gas heat exchanger 4 to the hot water heat exchanger 5 and heated until the water reaches a high temperature of 80°C. death,
The water supply was made to be of drinkable quality.

In this way, in the conventional system, due to the indirect gas/water exchange system, the high amount of heat contained in the exhaust gas is absorbed.

The latent heat of vaporization could not be recovered as heat, but was released as water vapor, carbon dioxide, etc. Furthermore, the temperature of the exhaust gas released is limited to 150 to 200°C to prevent low-temperature corrosion. Therefore, the maximum thermal efficiency of the system has been limited to about 80%.

Note that in the one-indirect method, when the temperatures on the gas side and the water side approach each other, the heat transfer area of the heat exchanger increases, making it impractical.

Also, in order to use the conventional system for drinking water, a hot water heat exchanger is installed in the path before hot water is supplied.

This required piping and also required a large installation area.

[Means for Solving the Problems] In the present invention, in combination with a gas/liquid direct contact latent heat recovery device (hereinafter referred to as a latent heat recovery device) that recovers heat by bringing exhaust gas into direct contact with water, latent heat of vaporization can also be recovered. Heat can be recovered, and
This water heater uses exhaust gas, which improves the discharge temperature of the exhaust gas so that it is almost atmospheric temperature, and also incorporates a hot water heat exchanger into the bottom of the latent heat recovery device, making the overall configuration compact. The present invention provides a water heater for supplying high temperature water suitable for drinking.

[Example] An embodiment of the present invention shown in FIG. 1 will be described below.

In the same figure, components equivalent to those in FIG. 2 are designated by the same reference numerals.

This is a latent heat recovery device, and its basic configuration includes a water supply pipe 9 having a shower-shaped faucet 9a at the top, an exhaust pipe 10, and a filling layer 11 in the approximately middle part directly below the water supply pipe 9.
, also at the bottom, for example.

A delivery section such as a slope section for supplying hot water to the next process.

12a, an exhaust gas supply pipe 13, and a hot water heat exchanger 14.

Further, exhaust gas is supplied to the exhaust gas supply pipe 13 from the exhaust pipe 1c of the gas engine 1, but the exhaust pipe 1c is connected to an exhaust manifold in which a plurality of exhaust ports of four cylinders etc. are combined into one supply port. It is preferable to form it.

Further, the delivery portion 12a may be formed by forming a plurality of through holes in the pedestal 12 instead of the sloped portion.

Furthermore, the hot water heat exchanger 14 uses the hot water supplied from the pedestal 12a of latent heat recovery as the heat source on the primary side, and uses the supplied water such as tap water (20°C) on the secondary side. ■ with warm water (5
2℃) and supplies clean hot water to heat exchanger 3, and most of the heated primary side hot water is pumped to pump 1.
5, the water is reused as feed water to the latent heat recovery system 6 through the branch pipe 16 (this water is at 25°C), and the highly acidic water and water generated in excess during heat conversion are recycled. The water is drained from another branch pipe 17 via a regulating valve 18.

In this way, latent heat recovery 6 is performed from the primary side of the hot water heat exchanger 14.
This is because the water supply is circulated between the two.

Supply water ■ for latent heat recovery is only necessary at the beginning.

After that, I can reduce the amount of water with a single adjustment valve to save money.

20 and 21 are hot water pumps, respectively.

That is, in the present invention, in the latent heat recovery step 6, the hot water obtained by recovering the heat amount of the exhaust gas to near atmospheric temperature is converted into clean hot water via the hot water heat exchanger 14, and then The hot water heat exchanger 14 is built into the bottom of the latent heat recovery chamber.

In addition, the gas engine 1 in the above embodiment may be a gas turbine, a diesel engine, etc. in addition to a gas engine, and is, in short, a technical concept that includes all prime movers that produce exhaust gas.

[Operation] The gas engine 1 drives the alternating current generator 2 to generate electric power, and the high-calorie exhaust gas (500° C.) discharged from the engine 1 is supplied after latent heat recovery.

In this state, when feed water (tap water at 20°C) is supplied from the water supply pipe 9 for latent heat recovery, the exhaust gas and water come into direct contact within the latent heat recovery device, and the water is received in a so-called latent heat recovery method. Hot water (52° C.) is supplied to the primary side of the heat exchanger 14 via the stand 12 . On the secondary side of the heat exchanger 14, this is converted into clean hot water, and when hot water (50°C) is sufficient, the hot water is supplied from the hot water pipe 7°, and when high temperature water is required, this hot water is Furthermore, in heat exchanger 3, 80
The hot water is reheated to ℃ and then supplied from the hot water pipe 7.

In this case, when water passes through the portion of the packed bed 11 where latent heat is recovered, the noise of the engine 1 is absorbed and removed to a large extent.

[Effect of the invention] The present invention is based on the use of a latent heat recovery device as a gas/water heat exchanger for exhaust gas, and the hot water obtained by this latent heat recovery device is converted into a hot water heat exchanger installed at the bottom of the latent heat recovery device. Hot water is supplied at an appropriate temperature using an exchanger, either directly or by being reheated using a cooling water heat exchanger.It has the following excellent effects. ■The latent heat recovery unit reduces exhaust gas Most of the heat is recovered,
Furthermore, since the system uses a cooling water heat exchanger that recovers the heat of the engine jacket to reheat it, the latent heat of vaporization of the exhaust gas, which could not be recovered with conventional systems, can be used, resulting in a thermal efficiency of 90~90. This has resulted in a significant improvement of 95%.

■In the latent heat recovery device, the exhaust gas and supply water come into direct contact, so the temperature of the exhaust gas discharged from the exhaust pipe drops to close to the temperature of the water supplied to the latent heat recovery device.

In addition, since it is diluted, there is no need to worry about low-temperature corrosion caused by condensed water (acidic water) in the exhaust gas, and there is no need to take safety measures to prevent acid corrosion from releasing high-temperature exhaust gas as with conventional products. It became.

■A hot water heat exchanger for converting into clean hot water is installed at the bottom of the latent heat recovery device.

Compared to conventional systems that were installed separately, the amount of piping can be significantly reduced, and the overall installation space can be made more compact than conventional systems.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of the entire apparatus showing one embodiment of the present invention, and FIG. 2 is a system diagram showing a conventional example. 1: Gas engine 2: Alternator 3: Cooling water heat exchanger 1: Latent heat recovery device 9: Water supply pipe 10: Exhaust pipe 11: Filled bed 12: pedestal 13: Exhaust gas supply pipe 14: Hot water heat exchanger

Claims (3)

[Claims] 1. A water heater that uses exhaust gas and consists of the following: a. A prime mover with exhaust gas such as a gas engine, diesel engine, or gas turbine (hereinafter referred to as engine) b. A cooling water heat exchanger using hot water for cooling the prime mover as the primary heat source of the cooling water heat exchanger c. A latent heat recovery device comprising a packed bed formed by stacking fillers and a hot water storage section located at the bottom d. Water supply pipe for supplying water to the latent heat recovery device e. Exhaust gas supply pipe f. which supplies the exhaust gas of the prime mover to the latent heat recovery device. Exhaust pipe for discharging exhaust gas from the latent heat recovery device g. A hot water heat exchanger that is attached to the bottom of the latent heat recovery device and heats the supplied water to hot water using the hot water stored in the hot water storage section of the latent heat recovery device as a heat source h. A route in which hot water from the hot water heat exchanger is reheated by the cooling water heat exchanger, and this is converted into high-temperature water and supplied for hot water supply. 2. A water heater that uses exhaust gas and consists of the following: a. Prime mover with engine exhaust b. A cooling water heat exchanger that recovers and uses not only the hot water for cooling but also the heat of the exhaust pipe as a primary heat source of the cooling water heat exchanger c. A latent heat recovery device comprising a packed bed formed by stacking fillers and a hot water storage section located at the bottom d. Water supply pipe for supplying water to the latent heat recovery device e. Exhaust gas supply pipe f. which supplies the exhaust gas of the prime mover to the latent heat recovery device. Exhaust pipe for discharging exhaust gas from the latent heat recovery device g. A hot water heat exchanger that is attached to the bottom of the latent heat recovery device and heats the supplied water to hot water using the hot water stored in the hot water storage section of the latent heat recovery device as a heat source h. A route for reheating the hot water in the hot water heat exchanger using the cooling water heat exchanger, converting it into high-temperature water, and supplying it for hot water supply. 3. The hot water supply system using exhaust gas according to claim 1 or 2, wherein hot water from the primary side of the hot water heat exchanger is circulated and used in addition to tap water as the supply water to the water supply pipe of the latent heat recovery device. .