JPS626449Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a control device for a direct-fired absorption chiller, and more specifically, it detects at least the inlet temperature of the cooling water pipe, compensates for the amount of heating depending on the cold water outlet temperature, and automatically sets the cold water temperature. The invention relates to a control device that controls the following.

Generally, the lower the temperature of the cooling water supplied to an absorption refrigerator, the more the absorption capacity in the absorber increases, and the refrigerant condensation effect in the condenser also increases, so the refrigeration capacity tends to increase. In this case, the cooling water temperature is influenced by the outside air temperature (particularly the wet bulb temperature) and the cooling load, and the lower the wet bulb temperature or cooling load, the lower the temperature of the cooling water that is cooled in the cooling tower and returned to the absorption chiller. Become. On the absorption chiller side, when the cooling water temperature decreases, the refrigeration capacity increases, so a proportional control system is adopted in which the chilled water temperature decreases and the capacity control device operates to reduce the refrigeration output, as shown in the example in Figure 1. As a result, the cold water temperature will decrease. However, when an absorption chiller is used for cooling, it is more convenient for the load to have a higher chilled water temperature when the outside temperature is low or when the cooling load is low; It is advantageous for the cold water temperature to drop when the water is heavy.

In view of the above circumstances, the present invention is designed to supply cold water at a temperature that matches the cooling load and outside temperature conditions when an absorption chiller or absorption chiller/heater is used for air conditioning. The present invention provides a control device that saves on volume.

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

Reference numeral 1 denotes a high-temperature generator for heating and separating refrigerant from a dilute liquid, which is equipped with a combustion heating chamber 2 heated by combustion of gas, etc., and the refrigerant vapor is introduced into the tip of a refrigerant vapor pipe 3 led from the high-temperature generator 1. A low-temperature generator 4 is provided as a heat source to reheat and further heat and separate the intermediate liquid refrigerant, and water flows from the low-temperature generator 4 into the side of the low-temperature generator 4 through a heat exchange pipe section 6 of a cooling water pipe 5. A condenser 7 is provided for condensing and cooling the refrigerant. Reference numeral 8 denotes an evaporator that obtains cold water for air conditioning from a cold water heat exchange pipe section 9 by utilizing latent heat when the refrigerant liquid from the condenser 7 is dispersed and vaporized. In the evaporator 8, the inside of the evaporator 8 is maintained at a low pressure by spraying a concentrated absorption liquid from which the refrigerant has been separated by the low temperature generator 4 to absorb the refrigerant vapor inside the container, thereby continuously supplying cold water. An absorber 10 configured as shown in FIG. 11 is a low temperature heat exchanger, 12 is a high temperature heat exchanger;
7. A refrigeration cycle is constructed by connecting the intermediate liquid pipe 18 and the concentrated liquid pipe 19. Reference numeral 20 denotes a detector 21 for the cold water outlet temperature of the cold water heat exchange pipe section 9 and a heat exchange pipe section 24 of the cooling water pipe 5.
This temperature regulator is connected to a cooling water inlet temperature detector 22, and a fuel control valve 23 for adjusting the heating provided in the combustion heating chamber 2 is attached to the temperature regulator 20.

To explain this function, first, as shown in the system diagram of Fig. 2, in addition to controlling the heating amount based on the chilled water outlet temperature, which is generally done, the coolant inlet temperature is detected by the detector 22, and this signal is detected. is added to the temperature controller 20.

Here, generally the design value of the cooling water inlet temperature of the absorption chiller is 32
℃, and if the cooling water inlet temperature is close to the design value, the opening degree of the fuel control valve 23 is adjusted via the temperature regulator 20 using only the signal of the chilled water outlet temperature to control the amount of heating and cooling. As the water temperature decreases, the chilled water control temperature will be raised. In this case, the temperature regulator 20 is provided with a mechanism that can arbitrarily set the width (see symbol D in FIG. 3) in which the chilled water outlet temperature setting changes automatically according to fluctuations in the coolant inlet temperature.
This allows the range of change in cooling water temperature and the change in cold water outlet temperature to be freely changed.

In addition, when detecting the cooling water temperature, a detector 22 may be provided at the cooling water outlet in addition to the cooling water inlet (not shown) to detect the cooling water inlet and outlet temperatures and send a signal of this temperature difference to the temperature regulator 20. In this case, when the cooling water temperature difference decreases, the chilled water temperature is increased, so that the coefficient of performance of the chiller increases and the amount of heating can be reduced.

As mentioned above, the present invention supplies chilled water at a temperature that meets the demands of the load by guiding the detectors placed at least at the cooling water inlet and chilled water outlet to the temperature controller connected to the heating control valve. At the same time, it is effective in saving the amount of heating such as fuel vapor without heating more than necessary. In addition, when the cooling water temperature is more than 10 degrees lower than the design value, operating with the design value of heat input may cause crystallization of the absorption liquid inside the absorption chiller. According to this means, the amount of heating is automatically limited by the temperature of the cooling water, so that it produces practical effects such as being advantageous.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the load and control state when a conventional device is used, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIG. 3 is an explanatory diagram of the same control state. 1... High temperature generator, 2... Combustion heating chamber, 4...
Low temperature generator, 5...Cooling water pipe, 7...Condenser, 8...Evaporator, 9...Cold water heat exchange pipe section, 10...Absorber, 11...Low temperature heat exchanger, 1
2... High temperature heat exchanger, 20... Temperature controller, 21
...Detector, 22...Detector, 23...Fuel control valve, 24...Heat exchange pipe section.

Claims (1)

[Scope of utility model registration request] A generator, condenser, evaporator, absorber, and heat exchanger are connected via piping to form a refrigeration cycle, and the opening degree of this fuel control valve is controlled by a fuel control valve installed in the combustion heating chamber of this generator. A temperature controller is installed to adjust and control the amount of heating of the absorption liquid in the generator according to the load factor, and a chilled water outlet temperature detector that detects the load is connected to this temperature controller, and the temperature from this detector is connected. A signal is sent to the fuel control valve as a control signal, and a temperature sensor of the cooling water supplied to the absorber and condenser is connected to the temperature controller, so that as the temperature of the cooling water decreases, the temperature of the cooling water increases. An absorption chiller that adjusts the opening degree of a fuel control valve by changing the magnitude of the control signal with a temperature controller so as to limit heating fuel under the same cold water temperature condition by raising the set temperature of the outlet temperature. Control device.