CN108534570B

CN108534570B - Absorption type large-temperature-difference heat exchanger unit

Info

Publication number: CN108534570B
Application number: CN201810520491.0A
Authority: CN
Inventors: 黄国华; 常晟; 秦冰
Original assignee: TONGFANG ENERGY-SAVING ENGINEERING TECHNOLOGY CO LTD
Current assignee: TONGFANG ENERGY-SAVING ENGINEERING TECHNOLOGY CO LTD
Priority date: 2018-05-28
Filing date: 2018-05-28
Publication date: 2024-04-09
Anticipated expiration: 2038-05-28
Also published as: CN108534570A

Abstract

An absorption type large-temperature-difference heat exchanger unit relates to the technical field of energy. The external loop of the machine set is divided into a primary network loop and a secondary network loop, and the internal loop is divided into a solution loop and a refrigerant loop. The primary network loop of the unit sequentially passes through the primary generator, the secondary generator, the water plate heat exchanger and the evaporator. The secondary net loop is connected with two paths in parallel, one path sequentially passes through the primary absorber, the secondary absorber and the condenser, the other path passes through the water plate type heat exchanger, and the two paths are mixed and then flow out of the unit. The AE cylinder body is internally provided with a first evaporation pressure, the AG cylinder body is internally provided with a second evaporation pressure, and the GC cylinder body is internally provided with a condensation pressure. Compared with the prior art, the invention can increase the temperature difference of the water supply and return of the primary side hot water of the central heating system, reduce the water return temperature of the heat supply network, and increase the conveying capacity of the heat supply network, and is especially suitable for areas and occasions with lower water supply temperature of the primary side.

Description

Absorption type large-temperature-difference heat exchanger unit

Technical Field

The invention relates to the technical field of energy, in particular to an absorption heat exchanger unit for heating and heat supply, which can be applied to occasions with lower hot water quality, such as a secondary station for central heating, solar hot water utilization, steam condensate depth utilization and the like.

Background

With the continuous increase of the central heating scale of cities, under the condition of the same heating load, the increase of the temperature difference of the water supply and return water of hot water can reduce the flow of the delivered hot water, thereby reducing the initial investment of the delivery pipeline and the power consumption of the water pump in the running process of the system.

In the prior art, the heat pump type heat exchanger unit is proposed in China, the temperature of hot water supply and return water of a primary network for central heating is generally about 130-60 ℃, and the temperature of the water supply and return water of the primary network in an embodiment is 130-25 ℃ and the temperature difference of the water supply and return water reaches 105 ℃. However, in most areas of the central heating of the city, the water supply temperature of the primary network can not reach 130 ℃, and especially in the initial and final stages of the heating, the water supply temperature of the primary network is basically only 70-80 ℃. At this time, due to the working characteristics of the absorption heat exchanger unit, the temperature of the driving heat source is reduced, so that the primary network backwater temperature is higher than 25 ℃, and even the unit cannot operate. Therefore, in practical application, when the water supply temperature of the primary network is low, the primary network is not suitable for the absorption heat exchanger unit of the type.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide an absorption type large-temperature-difference heat exchanger unit. The water supply and return temperature difference of the primary side hot water of the central heating system can be increased, the water return temperature of the heat supply network can be reduced, the conveying capacity of the heat supply network can be increased, and the water supply and return system is particularly suitable for areas and occasions with lower primary side water supply temperature.

In order to achieve the above object, the technical scheme of the present invention is implemented as follows:

an absorption type large temperature difference heat exchanger unit comprises an external loop and an internal loop. The external circuit is divided into a primary network circuit and a secondary network circuit, and the internal circuit is divided into a solution circuit and a refrigerant circuit. The unit is structurally characterized by comprising an AE barrel body composed of a primary absorber and an evaporator, an AG barrel body composed of a generator and a secondary absorber, a GC barrel body composed of a primary generator, a condenser and a secondary generator and a water-water plate type heat exchanger. The primary network loop sequentially passes through the primary generator, the secondary generator, the water-water plate heat exchanger and the evaporator. The secondary net loop is connected with two paths in parallel, one path sequentially passes through the primary absorber, the secondary absorber and the condenser, the other path passes through the water plate type heat exchanger, and the two paths are mixed and then flow out of the unit. The AE cylinder body is internally provided with a first evaporation pressure, the AG cylinder body is internally provided with a second evaporation pressure, and the GC cylinder body is internally provided with a condensation pressure.

By adopting the structure, the three cylinders form three different pressures, and the three pressures bring about sectional cooling/heating, so that the temperature difference of the water supply and return of the primary side hot water in the central heating system can be obviously increased, the water return temperature of the heat supply network is reduced, and the conveying capacity of the heat supply network is improved. The invention is especially suitable for areas and occasions with lower primary side water supply temperature, and equipment can be effectively utilized even at the initial and final stages of heating. Compared with the traditional plate heat exchanger unit, the primary side backwater temperature is lower and lower than the secondary side backwater temperature, so that conditions are created for recycling low-grade heat energy in a heat source plant, and the comprehensive energy utilization efficiency of the system is improved.

The invention is further described below with reference to the drawings and the detailed description.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Detailed Description

Referring to fig. 1, the absorption type large temperature difference heat exchanger unit of the present invention includes an outer loop and an inner loop. The external circuit is divided into a primary network circuit and a secondary network circuit, and the internal circuit is divided into a solution circuit and a refrigerant circuit. The unit comprises an AE cylinder body composed of a primary absorber A1 and an evaporator E, an AG cylinder body composed of a generator G and a secondary absorber A2, a GC cylinder body composed of a primary generator G1, a condenser C and a secondary generator G2, and a water plate type heat exchanger W. The primary network loop sequentially passes through the primary generator G1, the generator G, the secondary generator G2, the water plate heat exchanger W and the evaporator E. The secondary network loop is connected with two paths in parallel, one path sequentially passes through the primary absorber A1, the secondary absorber A2 and the condenser C, the other path passes through the water plate type heat exchanger W, and the two paths are mixed and then flow out of the unit. The AE cylinder forms the first evaporation pressure, the AG cylinder forms the second evaporation pressure, and the GC cylinder forms the condensation pressure.

The solution loop in the internal loop is divided into two independent paths, and one path of solution sequentially passes through the first-stage absorber A1, the first-stage generator G1 and the generator G and then returns to the first-stage absorber A1 to be circularly reciprocated; the other path of solution sequentially passes through the secondary absorber A2 and the secondary generator G2 and then returns to the secondary absorber A2 to be circularly reciprocated. The refrigerant circuit in the inner circuit of the present invention goes from the condenser C to the evaporator E. In the present invention, the circulation direction, the number of pumps, the control mode of the pumps, and the like are not limited when the internal solution circulates.

The invention provides a solution for gradient utilization of medium-low temperature energy of central heating hot water, and can provide heating or domestic hot water. When the water heater works, the central heating hot water sequentially passes through the first-stage generator G1, the generator G, the second-stage generator G2, the water-water plate heat exchanger W and the fifth-stage cooling of the evaporator E, so that the return water temperature of the central heating hot water is greatly reduced. Due to the special structures of the AG cylinder and the GC cylinder, the usable temperature of the driving hot water is between 65 and 100 ℃. When the primary generator G1 in the invention does not work, the tube side of the primary generator G is only used as a circulating channel of hot water, and at the moment, the available temperature of the driving hot water is between 65 and 80 ℃.

The invention reduces the temperature of the heat supply backwater, and the backwater pipeline has no heat preservation and thermal stress compensation problems, thus reducing the investment of backwater pipe network and the whole pipe network. In addition, for certain areas, the temperature condition of the central heating hot water is low, the improvement by adopting the absorption heat exchanger unit can be considered, and the absorption heat exchanger unit has good adaptability to the initial and final stages of heating.

Claims

1. An absorption type large-temperature-difference heat exchanger unit comprises an external loop and an internal loop, wherein the external loop is divided into a primary network loop and a secondary network loop, and the internal loop is divided into a solution loop and a refrigerant loop; it is characterized in that the method comprises the steps of,

the unit comprises an AE barrel body composed of a primary absorber (A1) and an evaporator (E), an AG barrel body composed of a generator (G) and a secondary absorber (A2), a GC barrel body composed of a primary generator (G1), a condenser (C) and a secondary generator (G2), and a water-water plate heat exchanger (W), wherein a primary network loop sequentially passes through the primary generator (G1), the generator (G), the secondary generator (G2), the water-water plate heat exchanger (W) and the evaporator (E), two paths are connected in parallel in the secondary network loop, one path sequentially passes through the primary absorber (A1), the secondary absorber (A2) and the condenser (C), and the other path passes through the water-water plate heat exchanger (W), and the two paths are mixed and then flow out of the unit; the AE cylinder body is internally provided with first evaporation pressure, the AG cylinder body is internally provided with second evaporation pressure, and the GC cylinder body is internally provided with condensation pressure;

the solution loop in the internal loop is divided into two independent paths, and one path of solution sequentially passes through the first-stage absorber (A1), the first-stage generator (G1) and the generator (G) and then returns to the first-stage absorber (A1) to be circularly reciprocated; the other path of solution sequentially passes through the secondary absorber (A2) and the secondary generator (G2) and then returns to the secondary absorber (A2) to be circularly reciprocated, and a refrigerant loop in the inner loop is from the condenser (C) to the evaporator (E).