JPH0457934B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a heat source device for a refrigeration cycle that can be efficiently operated in winter heating operation, and is also safe. This article relates to a heat pump system that utilizes total heat and is expected to be widely used in large-scale heat source facilities such as industrial facilities.

[Conventional technology]

Air-cooled heat pump refrigerators have been used as cold/hot heat source equipment in conventional refrigeration cycles.
In this method, outside air is passed through a heat exchange surface in an outdoor heat exchanger, and the sensible heat of the air is used to condense the refrigerant in the summer and evaporate the refrigerant in the winter. . In this case, since an air exchanger is used, refrigerant piping is required to reach the rooftop.
In addition to having legal and safety problems, the heat exchange efficiency is also poor, and the coefficient of performance of the refrigerator is also poor. Additionally, in winter, a defrost cycle is added to melt the ice that adheres to the coil surface, causing a decline in performance.

Therefore, in addition to using the cooling tower as a heating tower, a system was devised in which antifreeze (ethylene glycol) was used as circulating water to prevent freezing. Figure 2 shows this method. In this system, antifreeze is circulated in the same manner as cooling water in the summer, and heat is taken from the outside air by using the sensible heat of the outside air in the heating tower 11.

[Problem that the invention seeks to solve]

However, in the case of the above method, it is necessary to maintain a concentration at which the antifreeze does not freeze even in the worst case, so the concentration of the antifreeze is high (40%), and polyprene glycol, which is safe as an antifreeze, cannot be used due to viscosity problems. Therefore, ethylene glycol is generally used. Furthermore, since accurate concentration control is required for the inflow and outflow of moisture generated during heat exchange with the atmosphere, there have been problems in terms of safety and use.

The present invention solves the above problems and aims to provide a total heat utilization type heat pump system that can use safe polyprene glycol as an antifreeze.

[Means for solving problems]

To this end, the total heat utilization type heat pump system of the present invention is a total heat utilization type heat pump system that uses a cooling tower as a heating tower during heating and makes it possible to use a low concentration aqueous solution of antifreeze as circulating water. The heating tower is equipped with a means for separating and melting partially frozen ice, and the system is configured to circulate an ice-free antifreeze aqueous solution from the heating tower to the refrigerator, and is configured to replenish water from the means. It is characterized by

[Effect]

In the total heat utilization type heat pump system of the present invention, the cooling tower is used as a heating tower during heating, and a low concentration aqueous solution (around 7%) of safe antifreeze (polyprene glycol) can be used as circulating water. In addition, by using piping with inner tubes or peelable double pipes that can prevent rupture due to expansion when aqueous solution freezes, even if the temperature drops below the freezing temperature of the brine solution in the heating tower, it is possible to partially separate and freeze. The melting temperature of ice can be obtained, and as a result, the refrigerant can be evaporated at a high temperature, and the concentration of the polyprene glycol aqueous solution used as circulating water can be roughly controlled, making it possible to obtain stable performance.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of one embodiment of the total heat utilization type heat pump system according to the present invention, in which 1 is a heating tower, 2 is a refrigerator, 3 is a hot water tank, and 4
5 indicates a heat exchanger, and 5 indicates a replenishment water tank/powdered ice storage pit.

In FIG. 1, when a heating tower 1 receives antifreeze solution in which some water has turned into ice from a refrigerator 2, the ice remains at the top and the aqueous solution of antifreeze sinks to the bottom. The aqueous solution of antifreeze with a certain concentration that has sunk to the bottom is sent to the refrigerator 2, and the ice that has floated to the bottom is sent to the replenishment water tank/powdered ice storage pit 5. The amount of ice circulating from the heating tower 1 to the supply water tank/powdered ice storage pit 5 is approximately 2.6% of the total circulating amount.
An amount of water corresponding to this amount is replenished from the replenishment water tank/powdered ice storage pit 5 to the aqueous solution of antifreeze circulating to the refrigerator 2. The heat exchanger 5 heats and melts the ice that has returned from the heating tower 1 to the makeup water tank/powdered ice storage pit 5, and uses atmospheric heat during the day, waste heat from sewage (gray water), and waste heat during the winter. Low-temperature water, etc., which is waste heat from cold water production, is used. Because a partially frozen antifreeze aqueous solution circulates in the piping, piping with internal coatings or peelable double pipes with inner tubes devised to prevent pipes from bursting due to freezing and expansion are used. Peelable double pipes are double pipes with an inner pipe and an outer pipe, with cold water passing through the inner pipe and hot water passing between the outer pipe and the inner pipe.

Next, the operation of the entire system will be explained. First, if the outside air is below 0℃, heating tower 1
At this point, an aqueous antifreeze solution with some of the water frozen will be sprayed. In this case, the antifreeze other than the ice absorbs heat from the outside air and becomes heated, and the ice accumulates in the water tank under the tower. Here, for example, the ratio of antifreeze solution other than water is 97.4%, and the ratio of ice is about 2.6%, of which the unmelted ice is separated using the floating property of ice. This ice is discharged to a powder ice storage pit 5 which also serves as a supply water tank. On the other hand, the ice-free aqueous antifreeze solution is replenished by a pump with water carried away by the ice, and is guided to the refrigerator 2 while maintaining a constant concentration of antifreeze. In the refrigerator 2, the aqueous solution that has obtained heat from the outside air is guided to an evaporator for heat exchange, and hot water is taken out from the condenser and stored in a hot water tank. In addition, in the make-up water tank/powdered ice storage pit 5, in order to melt the ice, a heat exchanger 4 is installed to collect high atmospheric heat during the day, sewage (gray water) waste heat, and low-temperature waste heat obtained from cold water production in the winter. exchange heat with etc.

The total heat utilization type heat pump system of the present invention is
In this way, the conventional heating tower type heat pump has been improved, taking into consideration the concentration control and safety of the antifreeze, and the antifreeze can circulate a dilute aqueous solution of hygienically safe polyprene glycol.

[Effects of the Invention] As is clear from the above description, according to the present invention, even viscous polyprene glycol can be made into a thin aqueous solution, and its viscosity is not a problem. Furthermore, piping that is compatible with the freezing of water in an aqueous solution may be used. Furthermore, since the concentration of antifreeze is kept constant at all times, efficient operation is achieved.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the configuration of one embodiment of the total heat utilization type heat pump system according to the present invention, and Fig. 2 explains a conventional system in which a cooling tower is used as a heating tower and antifreeze is used as circulating water. This is a diagram for 1...Heating tower, 2...Freezing machine, 3...Hot water tank, 4...Heat exchanger, 5...Supplementary water tank/powdered ice storage pit.

Claims (1)

[Scope of Claims] 1. A total heat utilization type heat pump system that uses a cooling tower as a heating tower during heating and makes it possible to use a low concentration aqueous solution of antifreeze as circulating water. The system is equipped with means for separating and melting partially frozen ice, and is configured to supply water from the means with a system for circulating an ice-free aqueous antifreeze solution from the heating tower to the refrigerator. Heat-utilizing heat pump system. 2. The total heat utilization type heat pump system according to claim 1, characterized in that polyprene glycol is used as the antifreeze and a low concentration aqueous solution of about 7% is circulated. 3. A total heat utilization type heat pump according to claim 1, characterized in that an antifreeze aqueous solution circulation system utilizes piping with inner tubes or peelable double pipes that can cope with rupture due to expansion when the aqueous solution freezes. system. 4. The total heat utilization type heat pump system according to claim 1, wherein the means includes a heat exchanger.