JPH01131859A - Cold and hot water controller - Google Patents

Abstract

PURPOSE: To lighten the load of an electric turbo refrigerating machine by making use of the quantity of heat recovered from waste heat preferentially to the demand of hot water supply, and making use of the surplus quantity of heat to a hot water system of absorption refrigerating machine. CONSTITUTION: The waste heat of an engine generator 5 is recovered with a cooling water heat recovery heat exchanger 7 and an exhaust gas heat recovery heat exchanger 6, and its heating medium is utilized, being circulated in a absorption refrigerating machine 1, a heat exchanger 3 for hot water supply heating, a cooling water heat recovery heat exchanger 7, and an exhaust gas heat recovery heat exchanger 6 in order. Moreover, the heat of the hot water made by the waste heat of the engine 5 is sent round preferentially to a heat exchanger 3 for hot water supply heating, by putting the control of three-way adjusting valves 18 and 19 fitted with controllers for hot water adjustment put in a hot water system of absorption refrigerating machine 1 into practice, operating the temperature information of the first temperature sensor 11 in the outlet line of the output side of that hot water system of absorption refrigerating machine 1 and the second temperature sensor 12 in the outlet line on the secondary side of the heat exchanger 3 for hot water supply heating with a central processing unit 4, and the waste heat is effectively made use of, by fulfilling a part of the cooling demand with surplus hot water.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cold/hot water control device applied to cold/hot water control for optimally economical operation of a cogeneration plant.

[Conventional technology]

A conventional control method for a hot water absorption refrigerator is a so-called l-loop local ml IIOr method, which controls the amount of water input so that the temperature of the produced cold water is constant. The control of hot water for hot water supply is also an l-loop local control that controls the burner so that the hot water temperature is constant. In this way, the cold water and hot water controls for both devices existed independently and were not related.

[Problem that the invention seeks to solve]

The optimal economic operation method for a cogeneration plant can be theoretically determined for electric power and heat demand using linear programming and the like.

According to this theory, it is most economical to satisfy the demand for hot water supply with the amount of heat obtained by recovering exhaust heat from the engine, and to use the surplus amount of heat to operate a hot water absorption refrigerator. However, the above-mentioned conventional hot water absorption chiller only uses so-called local control to control the amount of hot water input so that the produced cold water has a constant temperature (for example, 7 degrees Celsius), and is able to achieve optimal economical operation as a 7 = 1 Sibelant. It was far from becoming a reality.

Furthermore, with regard to hot water for hot water supply, burner ignition is only automatically controlled when the water temperature is low, and there is no means for detecting surplus heat, and as described above, optimal economical operation of the plant has not been achieved.

The present invention enables optimal economical operation by preferentially utilizing the recovered waste heat for hot water demand and using the excess heat in a hot water absorption chiller to reduce the load on the electric centrifugal chiller. The purpose is to

[Means for solving problems]

The present invention takes the following measures to solve the above problems.

That is, the exhaust heat of the engine generator is recovered by the cooling water heat recovery heat exchanger and the exhaust gas heat recovery heat exchanger, and the heat medium is sequentially transferred to the absorption refrigerator, the hot water supply heating heat exchanger, and the above-mentioned cooling water heat recovery heat exchanger. In a cogeneration plant in which the exhaust gas is circulated to a heat recovery heat exchanger for use and a refrigerator other than the above is used in conjunction with the absorption refrigerator, a first a temperature sensor, a three-way regulating valve with a control device disposed on the outlet side of the input line of the absorption chiller, and a second temperature sensor disposed on the outlet line of the secondary side of the heat exchanger for hot water supply and heating. , a central processing unit connected to each of the temperature sensors and the three-way regulating valve with a control device by a signal line, and a three-way regulating device with a control device disposed on the outlet side of the primary line of the heat exchanger for hot water supply and heating. The exhaust heat recovered from the engine generator is preferentially used for hot water supply and heating, and the surplus heat is used for cooling.

[Effect]

The three-way regulating valve with a control device for adjusting the amount of hot water input to the hot water absorption chiller is controlled by the first temperature sensor on the output line of the hot water absorption chiller and the secondary side of the hot water heating heat exchanger. By calculating and executing the temperature information from the second temperature sensor on the outlet line in the central processing unit, the heat of the hot water created by the engine exhaust heat is preferentially routed to the hot water supply and heating heat exchanger. By meeting a portion of the venue's cooling demand with surplus hot water, waste heat is used effectively and in the most economical way as a cogeneration plant.

〔Example〕

An embodiment of the present invention will be explained with reference to FIG.

Cooling water heat recovery heat exchanger 7 in the cooling water system of the engine generator 5
, an exhaust gas heat recovery heat exchanger 6 is provided in the exhaust system. The secondary side outlet of the cooling water heat recovery heat exchanger 7 is connected to the first boat of the first three-way regulating valve (the following first to fifth three-way regulating valves are all equipped with a control device) equipped with a control device. Ru. The secondary side inlet line of the exhaust gas heat recovery heat exchanger 6 is connected to the outlet line of the cooling water heat recovery heat exchanger 7, and the outlet line is connected to the second boat of the first three-way regulating valve n. Also, the third boat (outlet) of the first three-way regulating valve n is a hot water type absorption refrigerator 1.
connected to the inlet of the input line. Second three-way regulating valve 18
The first boat is connected to the inlet of the input line of the absorption chiller l, and the second boat is connected to the outlet of the input line of the absorption chiller l. In addition, the third port (outlet) of the second three-way regulating valve 18 is connected to the inlet of the primary side of the hot water heating heat exchanger 3, and the line to the population on the same outgoing side is connected to the first boat of the third three-way regulating valve 19. Connected. Also, the third three-way regulating valve 1
The second boat No. 9 is connected to the first water line of the hot water/heating heat exchanger 3, and the third boat (outlet) is connected to the first boat of the fourth three-way adjustment valve.

The second boat (outlet) of the fourth three-way regulating valve is connected to the secondary side inlet of the cooling water heat recovery heat exchanger 7 via the circulating water heat radiation heat exchanger 8, and the third boat (outlet) is connected to the circulating water Radiation heat exchanger 8
are connected to the respective exit lines.

On the other hand, the output line outlet of the absorption refrigerator 1 is connected to one inlet of the mixer 10. The outlet of the mixer 10 is connected to a cooling supply line a via an electric centrifugal refrigerator 2. The cooling supply return line b is connected to the output side inlet of the absorption refrigerator 1 and the other inlet of the mixer 10 via the cooling cold water return header 9.

On the other hand, the outlet on the secondary side of the heat exchanger 3 for hot water supply and heating is the fifth
The first boat of the three-way regulating valve 21 is connected to the hot water/heating supply 2-in C via the third boat (outlet). Further, a hot water boiler is connected between the line of the fifth three-way regulating valve 21 to the first boat and the second boat. In addition, the above hot water supply
The return line d of the heating supply line C is connected to the secondary side inlet of the hot water supply and heating heat exchanger 3.

In order to control the above-mentioned devices, the central processing unit 4 controls the second three-way regulating valve 18 and a first temperature sensor (hereinafter abbreviated as the first sensor, other The same applies to the temperature sensor) 11, and a second sensor 12 provided on the outlet line on the secondary side of the hot water supply/heating heat exchanger 3.
are connected to each other. Further, the first three-way regulating valve n is a third valve provided at the outlet exhaust pipe of the exhaust gas heat recovery heat exchanger 6.
Connected to sensor 16. The fourth three-way adjustment valve is the fourth three-way adjustment valve installed in the inlet line on the secondary side of the cooling water heat recovery heat exchanger 7.
Connected to the cell/su15.

Further, the third three-way regulating valve 19 is connected to the fifth sensor 13 provided on the line of the third boat, and the fifth three-way regulating valve 21 is connected to the sixth sensor 14 provided on the line of the third boat. . Further, the electric centrifugal refrigerator 2 is connected to a seventh sensor provided on its outlet line.

In the above configuration, the exhaust heat of the engine generator 5 is recovered as hot water heat via the cooling water heat recovery heat exchanger 7 and the exhaust gas heat recovery heat exchanger 6.

This hot water is supplied to the second three-way regulating valve 18 and the third three-way regulating valve 19.
By controlling the opening degrees of the water, a predetermined amount of water is supplied to the absorption refrigerator 1 and the hot water supply/heating heat exchanger 3, respectively. Since the temperature of the water supplied to the cooling water heat recovery heat exchanger 7 needs to be kept constant, the opening degree of the third three-way regulating valve 19 is controlled by the fifth sensor 13 so that the water temperature does not fall below a set value.

When the demand for air conditioning and hot water supply is low and the water temperature is higher than the set value, adjust the opening of the fourth three-way control valve and close the circulating water heat radiation heat exchanger 8.
Lower the water temperature and maintain the set value.

Further, when the demand for heating and hot water supply is high and the water temperature at the second sensor 12 is low, the second three-way regulating valve 18 reduces the hot water supply to the absorption chiller 1 and increases the hot water supply to the hot water supply and heating heat exchanger 3. If the opening degree of the third three-way regulating valve 19 remains the same, the fifth stage/
Since the water temperature in the bath 13 rises, this signal increases the amount of water supplied to the hot water heating heat exchanger 3. Further, when the temperature of the hot water for hot water supply and heating decreases, additional heating is performed in the hot water boiler 223.

If the water temperature in the 12th part of the 27th sensor is high (if there is surplus heat), the water temperature in the 12th part of the 27th sensor is higher than the setting, and
If the chilled water temperature of sensor 11 is higher than the set value, that is, if the amount of waste heat recovery is greater than the hot water demand, and if the chilled water temperature is higher than the set value, the central processing unit [4] determines that the cooling demand is large. Then, the second three-way regulating valve 18 is adjusted to increase the supply of hot water to the absorption chiller 1 to an extent that the temperature of the second sensor 12 does not fall below the set value, thereby increasing the water temperature of the first sensor 11. Lower it. The cold water temperature on the output side of the absorption chiller 1, that is, the water at the first sensor 11 section, is mixed with another circuit of return cold water for cooling in a mixer 1o, and is supplied to the electric centrifugal chiller 2. Since the electric centrifugal refrigerator 2 is controlled so that the water temperature at the outlet of the seventh sensor 17 section is constant, the power consumption decreases as the water temperature of the first sensor 11 section decreases. Furthermore, even if the water temperature at the second sensor 12 section is high, if the cold water temperature at the first sensor 11 section is lower than the set value (for example, 7°C) i, the absorption chiller 1
The amount of hot water supplied to the area will not increase.

Note that as the electric power for the electric centrifugal chiller 2, either the electric power generated by the engine generator 5 or the electric power supplied from the electric power company may be used. The electric centrifugal refrigerator 2 may be independent of the absorption refrigerator 1, and may be a gas-fired or oil-fired refrigerator. Although one engine generator 5 is illustrated, a plurality of engine generators 5 may be installed as is generally used in a cogeneration plant. Although this embodiment does not mention electricity purchased from the electric power company, it goes without saying that the electricity generated by the engine generator 5 and the electricity purchased can be treated as the same thing since they are included in the same line. .

Further, although the absorption refrigerator 1 is exemplified as a hot water type absorption refrigerator, it may be a steam type absorption refrigerator.

As described above, in a cogeneration plant, the exhaust heat recovered from the engine is first used preferentially for hot water supply and space heating, and the surplus heat is supplied to the absorption chiller and used for part of the cooling demand. Water control becomes possible.

〔Effect of the invention〕

When implementing optimal economical operation as a COGENERA 74 plant, it is best to first use the heat recovered from the engine exhaust heat for hot water supply and space heating first, and then supply the excess heat to the absorption chiller and use it to meet part of the cooling demand. With the cold/hot water control device of the present invention, the above can be concretely realized.

3: Hot water heating heat exchanger, 4: Central processing unit, 5: Engine generator, 6: Exhaust gas heat recovery heat exchanger, 7: Cooling water heat recovery heat exchanger, 8: Circulating water radiation heat exchanger, 9 : Cold water return header for cooling, lO: Mixer, 11: 1st section, 12
: 2nd se/su, 13: 5th sensor, 14: 6th se/su,
15: Fourth sensor, 16: Third sensor, 17: Seventh sensor, 18: Second three-way regulating valve, 19: Third three-way regulating valve, 2
0: Fourth three-way regulating valve, 21: Fifth three-way regulating valve, 22: First three-way regulating valve, 23: Hot water boiler.

Agent: Patent Attorney: Sakama Akatsuki, 2 others, 1 illustration

Claims (1)

[Claims] The exhaust heat of the engine generator is recovered by a cooling water heat recovery heat exchanger and an exhaust gas heat recovery heat exchanger, and the heat medium is sequentially transferred to an absorption refrigerator, a hot water supply and heating heat exchanger, the above-mentioned cooling water heat recovery heat exchanger, In a cogeneration plant in which exhaust gas heat is circulated to a heat recovery heat exchanger for use and a refrigerator other than the above is used in combination with the absorption refrigerator, a first temperature sensor installed in an outlet line on the output side of the absorption refrigerator. a three-way regulating valve with a control device disposed on the outlet side of the input line of the absorption chiller; and a second temperature sensor disposed on the outlet line of the secondary side of the hot water supply and heating heat exchanger. A central processing unit connected to each of the temperature sensors and the three-way regulating valve with a control device via a signal line, and a three-way regulating valve with a control device disposed on the outlet side of the primary line of the heat exchanger for hot water supply and heating. A cold/hot water control device for a cogeneration plant, characterized in that the exhaust heat recovered from the engine generator is preferentially used for hot water supply and heating, and the surplus heat is used for cooling.