KR100340798B1 - Ammonia GAX absorption cycle - Google Patents

Abstract

The present invention relates to an ammonia GAX (GAX) absorption cycle in which the generator is heated and heat is recovered from the exhaust gas to maximize the cycle performance coefficient (COP).

One embodiment of the present invention includes a generator 10 for generating a refrigerant vapor and a refrigerant aqueous solution (weak solution) from a working solution (strong solution) by heat generated in a burner, a refrigerant vapor obtained from the generator 10 An evaporator 30 for evaporating the liquid refrigerant discharged from the condenser 20 by using cold water whose temperature has risen to make it a refrigerant vapor, a condenser 20 for condensing the liquid refrigerant discharged from the condenser 20, And an absorber (40) for producing a strong solution with a continuous absorption action which causes the weak solution to absorb the refrigerant vapor generated in the generator (10), wherein the GFD (11), the SHD The SCA 41, the GAX 42 and the HCA 43 are provided in the absorber 40, and the GAX 42 and the HCA 43 are provided in the absorber 40. The SCA 41, the partial condenser 14, A portion of the steel solution flowing into the upper portion of the SHD 12 through the outlet 42 of the GFD 11 and the outlet combustion gas of the GFD 11, And an auxiliary GFD (101) for supplying the air to the upper portion of the SHD (12).

Description

Ammonia GAX absorption cycle < RTI ID = 0.0 >

The present invention relates to an ammonia GAX absorption cycle, and more particularly to an ammonia GAX absorption cycle in which the generator is heated and heat is recovered from the exhaust gas to maximize the cycle's coefficient of performance (COP) .

Conventional ammonia GAX (Absorbent Heat Exchanger) absorption cycle, as shown in FIG. 1, evaporates refrigerant from a working solution (strong solution) having high concentration by heat generated in a burner (not shown) to obtain refrigerant vapor (10) for generating a refrigerant aqueous solution (weak solution) having a low concentration generated by evaporation of some refrigerant at the same time, and a cooling water which is cooled after cooling the refrigerant vapor obtained from the generator (10) An evaporator 30 for evaporating the liquid refrigerant discharged from the condenser 20 by using cold water whose temperature has risen from the indoor unit to make refrigerant vapor; An absorber 40 for producing a strong concentrated solution by a continuous absorption action which causes the weakly acidic solution to absorb the refrigerant vapor generated in the absorber 40, And a refrigerant heat exchanger 60 for exchanging the refrigerant vapor evaporated in the evaporator 30 with the condensed liquid refrigerant in the condenser 20 .

A gas-fired desorber (GFD) 11 for obtaining a refrigerant vapor by evaporating a refrigerant with a high-temperature combustion gas in the generator 10 and generating a high-temperature chemical solution having a low concentration generated by evaporating a part of the refrigerant, A solution heated desorber (SHD) 12 for exchanging the chemical solution generated in the evaporator 11 with the steel solution supplied from the upper part to the absorber 40, and a condenser for condensing the vapor evaporated together with the refrigerant vapor, A condenser 20 for condensing the refrigerant vapor in the condenser 20 and cooling the refrigerant vapor in the solution supplied from the solution pump 50, A partial condenser 14 for returning the heated solution to the absorber 40 and returning the heated solution to the absorber 40 and the condensed liquid being in direct contact with the refrigerant vapor in the rectifier 13, Raise the also which a riser Anna (Analyzer, 15) installed to increase the refrigerant vapor and the heat concentration is supplied to the upper portion rises at the bottom with a steel solution passed through the absorber (40).

A solution of SCA (Solution A) is supplied to the absorber 40 to heat a part of the refrigerant discharged from the partial condenser 14 to partially absorb the refrigerant vapor generated in the evaporator 30, The remaining portion of the steel solution passed through the SCA 41 is heat exchanged to partially absorb the refrigerant vapor generated in the evaporator 30 and then sent to the upper portion of the SHD 12, The HCA is cooled by using cooling water which is obtained by exchanging the heat generated by the absorption of the refrigerant vapor generated in the evaporator 30 with the outside air in the outdoor unit through the SCA 41, And 43 are provided.

The operation and effect of the conventional ammonia GAX absorption cycle thus constructed will be described below.

First, we explain the principle of operation of ammonia absorption cycle based on basic structure to help technical understanding.

In the generator 10, there is a refrigerant aqueous solution, that is, an aqueous ammonia solution. The ammonia evaporates at a temperature lower than that of water.

Therefore, when the generator 10 is heated by a burner (not shown), water and ammonia are separated from each other. At this time, the ammonia which is not evaporated is mixed with water in a thin state.

The separated pure ammonia is subjected to heat exchange through the condenser 20 and the evaporator 30.

At this time, since the generator 10 and the condenser 20 form a high-pressure portion and the evaporator 30 and the absorber 40 form a low-pressure portion, the ammonia condensed in the condenser 20 is directly supplied to the evaporator 30 The ammonia discharged through the evaporator 30 flows into the absorber 40 and the weakly mixed solution of water and ammonia generated in the generator 10 directly enters the absorber 40 to be introduced into the evaporator 30 30) to absorb the ammonia and turn into a river solution.

Next, the detailed operation of the conventional ammonia GAX absorption cycle in which the above-described operation principle is applied will be described.

First, when heat (about 1400 to 1600 占 폚) generated from a burner (not shown) is applied to the generator 10, the GFD 11 absorbs heat to generate a strong solution 180 deg. C) is generated with a refrigerant vapor and a weak solution (about 200 deg. C), and the refrigerant vapor flows into the rectifier 13 while rising.

At this time, the condenser in which some refrigerant vapor is condensed flows through the rectifier (13) by the solution supplied from the solution pump (50) in the partial condenser (14), so that the refrigerant vapor is rectified to the high concentration refrigerant vapor by mass transfer.

The partial condenser 14 sends the refrigerant vapor that has passed through the rectifier 13 to the condenser 20 and at the same time condenses a part of the refrigerant vapor to return the condensate to the rectifier 13, (About 50 ° C) to raise the temperature of the solution (ca. 100 ° C) to the boiling point by the absorption heat in the SCA 41, .

The refrigerant vapor flowing into the condenser 20 is condensed by the liquid refrigerant through heat exchange with the cooling water and then flows into the evaporator 30. The temperature of the refrigerant vapor in the indoor unit is raised to exchange heat with the cold water flowing into the evaporator 3, And the cold water is sent to the indoor unit after the temperature is lowered by the latent heat of evaporation to perform the cooling.

The refrigerant vapor evaporated in the evaporator 30 passes through the refrigerant heat exchanger 60. The temperature of the liquid refrigerant by heat exchange with the condensed liquid refrigerant in the condenser 20 is close to the evaporation temperature in the evaporator 30 And the temperature of the refrigerant vapor is evaporated while a small amount of refrigerant that does not evaporate in the evaporator 30 is evaporated while the temperature of the condensate coming out of the condenser 20 is raised.

The refrigerant vapor evaporated in the evaporator (30) is heat-exchanged in the refrigerant heat exchanger (60) and then flows into the absorber (40).

On the other hand, the solution remaining after the refrigerant vapor is generated in the GFD 11 is supplied to the SHD 12 and is heat-exchanged with the steel solution supplied from the upper part, so that the solution flows into the upper part of the absorber 40 at a temperature lowered to about 150 캜 .

The SCA 41 is supplied with the steel solution through the partial condenser 14 and the absorption heat generated when a portion of the refrigerant vapor supplied through the refrigerant heat exchanger 60 is absorbed into the weak solution is removed, A portion of the river solution is supplied to the upper portion of the annularizer 15 and the rest of the river solution is supplied to the cooling solution of the GAX 42. [ The steep solution supplied to the GAX 42 is supplied to the upper portion of the SHD 12 after the temperature is raised by removing the absorption heat generated when the refrigerant vapor supplied through the refrigerant heat exchanger 60 is absorbed into the weak solution.

Here, the steel solution flowing into the SCA 41 is heated by the absorption heat generated when the refrigerant vapor is absorbed into the weak solution in the absorber 40, the temperature rises to the boiling point (about 100 ° C) Is heated by the absorption heat generated when the refrigerant vapor is absorbed into the weak solution and starts to boil and is supplied to the upper portion of the SHD 12 in a gas-liquid overflow state (about 140 ° C).

Then, the strong solution introduced into the upper portion of the SHD 12, which is the middle temperature portion of the generator 10 via the GAX 42 after the heat exchange with the weak solution, is mixed with the weak solution flowing in the SHD 12 in the generator 10, Then, descend.

Then, the steel solution flowing into the SCA 41 is heat-exchanged with the GAX 42 to absorb heat absorbed when the weakened solution absorbs the refrigerant vapor, and after the temperature rises, So that the refrigerant vapor is partially absorbed by the refrigerant vapor while being in contact with the refrigerant vapor generated in the generator 10 so as to rectify the refrigerant vapor.

At this time, the ammonia GAX absorption cycle performs cooling by sending the cold water having a temperature lowered in the evaporator 30 to the indoor unit during cooling, and the cooling water that has cooled the condenser 20 and the HCA 43 is sent to the outdoor unit do.

During heating, cold water whose temperature rises while passing through the condenser (20) and the absorber (40) is heated to be sent to the indoor unit, and cooling water having passed through the evaporator (30) is sent to the outdoor unit.

The above-mentioned operation is performed in a continuously circulated state in the equilibrium state during the operation of the system.

In the ammonia GAX absorption cycle as described above, GFD is a type of high temperature heat exchanger that exchanges heat with the combustion gas, which takes heat from the combustion gas to generate most of the refrigerant vapor while supplying a weakly concentrated high temperature solution to the absorber, It is the most basic element that can absorb refrigerant vapor.

The GFD determines the thermal efficiency according to how much heat is taken from the flue gas. That is, the following equations (1) and (2) can be set as the ratio of the absorption heat amount of the GFD (Q _GFD ) to the gas consumption amount (Q _gas ).

However, the generator thermal efficiency of the absorption system is very low compared to the thermal efficiency of the hot water boiler. The reason for this is that the temperature of the fluid (hot water) exchanging heat with the combustion gas in the case of the boiler is about 50-70 ° C, whereas the absorption heat pump is about 100 ° C higher than the boiler.

Therefore, the absorption type system can not efficiently utilize the heat of combustion.

Referring to the schematic diagram of the GFD shown in FIG. 2, the thermal efficiency of the heat exchanger can be obtained by the following equation (3) based on the enthalpy of the combustion gas.

In the figure, T _{exh, i} is the inlet combustion gas temperature, T _{exh, o} is the exit flue gas temperature, T _s, and _i is strong solution temperature, T _{v, o} is a refrigerant vapor temperature, T _{s, o} Is the solution temperature.

Where G _exh is the flow rate of the combustion gas, G _fuel is the fuel consumption, and? Is the calorific value per weight of the fuel unit.

Let _GFD and Q _GFD denote the amounts of heat received by the GFD when the exit combustion gas temperature is T'exh _{, o} and T _{exh, o} , respectively. Equation 4 is as follows.

Again, it is summarized as an efficiency variation DELTA eta / DELTA T _exh per 1 deg. C of the outlet combustion gas temperature and expressed as an excess air ratio alpha during fuel combustion.

Here, m _O2 is the number of oxygen moles required for the combustion per fuel 1 mole (mol), M _fuel is the molar equivalent of the fuel, M _O2 is the oxygen molar equivalents, M _N2 is the molar equivalent of N, C _p is It is the specific heat of the combustion gas.

On the other hand, the generator inlet temperature of the GAX absorption system is around 170 ℃, though there will be some difference depending on the type of high temperature heat exchanger. Regardless of the size of the heat exchanger, the outlet temperature of the combustion gas never exceeds the solution inlet temperature and the maximum heat efficiency η _max is obtained when the size of the heat exchanger is infinitely large and the outlet combustion gas temperature is equal to the inlet temperature of the solution.

That is, the maximum thermal efficiency that can be obtained is T _{exh, o} ≥ T _{s, i} , where T _{exh, o} = T _{s, i} in FIG. 2, thermal efficiency η _max is calculated from Equation 3 as shown in Equation 6 below .

The difference between the maximum thermal efficiency and the actual thermal efficiency is caused by the enthalpy difference corresponding to the difference between the lowest exit combustion gas temperature (T _{s, i} ) and the actual combustion gas temperature that can be obtained, it means. This can be expressed simply from Equation (4) as Equation (7) below.

For example, assuming that the combustion of methane (CH ₄ ) in the combustion of natural gas is assumed to be complete combustion, the thermal efficiency according to the change of the outlet combustion gas temperature 1 ° C when α = 0.7 (in general, excess air ratio is 07 to 0.8) The amount of change can be calculated from Equation (5) as Equation (8) below.

That is, there is a thermal efficiency change of 0.065% per 1 ° C of the outlet combustion gas temperature change. It can be guessed that the thermal efficiency of the generator is basically lowered by comparing it with the case of the hot water boiler and the absorption heat pump generator.

For example, assuming that the inlet temperature of the hot water boiler is 50 ° C and the generator inlet temperature is 150 ° C, which is 100 ° C higher than this, the difference (Δη _max ) between the respective maximum thermal efficiencies is expressed by Equation (9) .

In other words, it can be seen that the heat efficiency of the generator is theoretically about 7% lower than that of the hot water boiler even if the thermal efficiency is excellent. This reduction in the underlying thermal efficiency is due to the solution temperature at the generator inlet.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve the above-mentioned problems of the prior art, namely, firstly, The temperature of the working solution has a temperature low enough to effectively recover energy in the combustion gas so that the temperature of the finally discharged combustion gas is minimized to improve the COP of the cycle. will be.

Technical Solution According to an aspect of the present invention, there is provided a refrigerator comprising a generator for generating refrigerant vapor and a weak solution from a steel solution by heat generated in a burner, a condenser for condensing the refrigerant vapor into liquid refrigerant using cooling water, An evaporator for evaporating the liquid refrigerant by using cold water having a raised temperature to make the refrigerant vapor; an absorber for producing a strong solution by continuous absorption action for allowing the solution to absorb the refrigerant vapor generated in the evaporator; A solution pump for sending the solution to the generator and a refrigerant heat exchanger for exchanging the refrigerant vapor evaporated in the evaporator with the liquid refrigerant condensed in the condenser, wherein the generator includes a GFD, a SHD, a rectifier, a partial condenser, And in an ammonia GAX absorption cycle having SCA, GAX and HCA in the absorber, And an auxiliary GFD for supplying a part of the solution into the generator by heat exchange with the outlet combustion gas of the GFD.

Figure 1 shows a conventional ammonia gas x (GAX) absorption cycle diagram.

Figure 2 is a schematic diagram of the GFD shown in Figure 1;

3 is an ammonia GAX absorption cycle diagram according to a first embodiment of the present invention.

4 is an ammonia GAX absorption cycle diagram according to a second embodiment of the present invention.

5 is an ammonia GAX absorption cycle diagram according to a third embodiment of the present invention.

6 is an ammonia GAX absorption cycle diagram according to a fourth embodiment of the present invention.

DESCRIPTION OF THE REFERENCE SYMBOLS

10: Generator 11: GFD

12: SHD 14: partial condenser

15: Annelizer 40: Absorber

41: SCA 42: GAX

50: solution pump 101: auxiliary GFD

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings.

≪ Embodiment 1 >

FIG. 3 shows the ammonia GAX absorption cycle diagram according to the first embodiment of the present invention. The same components as those of the conventional cycle shown in FIG. 1 are denoted by the same reference numerals.

As shown, the generator 10, the condenser 20, the evaporator 30, the absorber 40, the solution pump 50, the refrigerant heat exchanger 60, the GFD 11, the SHD 12, (12) via the GAX (42) in an absorption cycle having a compressor (13), a partial condenser (14), an anaeraser (15), an SCA And an auxiliary GFD (101) for exchanging a part of the steel solution flowing into the upper portion with the outlet combustion gas of the GFD (11) and supplying the heat to the upper portion of the SHD (12).

The operation and effect of the ammonia GAX absorption cycle according to the first embodiment of the present invention will be described with reference to FIG. 3. The same function as the conventional ammonia GAX absorption cycle shown in FIG. 1 is described in detail Will be omitted.

First, when heat generated from a burner (not shown) is applied to the generator 10, the GFD 11 absorbs heat and a strong solution, which is a working solution in the generator 10, is generated as a refrigerant vapor and a weak solution. The refrigerant vapor is raised in the generator (10).

The chemical solution that has a specific gravity higher than that of the steel solution in the generator 10 is heat exchanged through the SHD 12 and then absorbed by the absorber 10 by the pressure difference between the generator 10, 40).

On the other hand, the steel solution flowing into the GAX 42 is supplied to the upper part of the SHD 12 in a gas-liquid overflow state where heat is exchanged when the weak solution absorbs the refrigerant vapor, and part of the steel solution is branched And supplied to the auxiliary GFD 101.

Then, the auxiliary GFD 101 heat-exchanges this steel solution with the outlet combustion gas of the GFD 11 and supplies it to the upper portion of the SHD 12 again.

The river solution flowing into the upper portion of the SHD 12 which is the middle temperature portion of the generator 10 through the GAX 42 and the auxiliary GFD 101 is uniformly dispersed in the generator 10 and flows in the SHD 12 After heat exchange with the solution, descend.

For example, the heat exchanger effectiveness of GFD 11 and auxiliary GFD 101 are ε _main = 0.95 and ε _sub = 0.5, inlet temperature T ₁ = 170 ° C. of GFD 11, and auxiliary GFD When the inlet temperature T _{2 of the} combustion chamber 101 is 140 ° C, the excess combustion air ratio α is 0.7, and the flame temperature T ₃ is 1400 ° C.,

Combustion gas exit temperature of GFD (11) T exit of the temperature of the combustion gas ₄ and the auxiliary GFD (101) T ₅ is shown in Equation 10 and 11 below, respectively.

That is, the temperature of the combustion gas finally discharged from the auxiliary GFD 101 was lowered from 232 ° C to 186 ° C by exchanging the low-temperature solution (140 ° C) from the GAX 42 with the combustion gas.

At this time, the improvement effect of the generator thermal efficiency with respect to the conventional cycle shown in FIG. 1 is calculated by Equation (9) as follows.

This increase in the thermal efficiency indicates the amount of heat recovery in the auxiliary GFD 101, and the amount of refrigerant vapor in the system increases accordingly, thereby increasing COP.

≪ Embodiment 2 >

FIG. 4 shows the ammonia GAX absorption cycle diagram according to the second embodiment of the present invention. The same components as those of the conventional cycle shown in FIG. 1 are denoted by the same reference numerals.

As shown, the generator 10, the condenser 20, the evaporator 30, the absorber 40, the solution pump 50, the refrigerant heat exchanger 60, the GFD 11, the SHD 12, The SCA 41, the GAX 42 and the HCA 43 in the absorption cycle of the annular riser 15 via the SCA 41, the partial condenser 14, the anaeraser 15, the SCA 41, the partial condenser 14, An auxiliary GFD 101 that selectively exchanges a part of the steel solution introduced into the upper portion of the SHF 12 with the outlet combustion gas of the GFD 11 to selectively supply the upper portion of the SHD 12 and the upper portion of the annular riser 15, As shown in FIG.

The operation and effect of the ammonia GAX absorption cycle according to the second embodiment of the present invention will be described with reference to FIG. 4. The same function as the conventional ammonia GAX absorption cycle shown in FIG. 1 is described in detail Will be omitted.

First, when heat generated from a burner (not shown) is applied to the generator 10, the GFD 11 absorbs heat and a strong solution, which is a working solution in the generator 10, is generated as a refrigerant vapor and a weak solution. The refrigerant vapor is raised in the generator (10).

The chemical solution that has a specific gravity higher than that of the steel solution in the generator 10 is heat exchanged through the SHD 12 and then absorbed by the absorber 10 by the pressure difference between the generator 10, 40).

On the other hand, the SCA 41 is supplied with the steel solution through the partial condenser 14, heat-exchanges the refrigerant vapor generated in the evaporator 30 so that the solution absorbs a part of the solution, and then supplies a part of the refrigerant vapor to the upper portion of the annular riser 15 The rest of the steel solution is heat exchanged through the GAX 42 to partially absorb the refrigerant vapor generated in the evaporator 30 and then supplied to the upper portion of the SHD 12. [

Here, the steel solution flowing into the SCA 41 is heated by the absorption heat generated when the refrigerant vapor is absorbed into the weak solution in the SCA 41, and the temperature rises to the boiling point (about 100 ° C.) A part of which is branched and supplied to the auxiliary GFD 101.

The auxiliary GFD 101 then exchanges this river solution with the outlet combustion gas of the GFD 11 to supply it to the top of the anaeraser 15 or to the top of the SHD 12.

When the auxiliary GFD 101 supplies the upper part of the SHD 12 with the solution, the GFD 101 flows into the upper part of the SHD 12, which is the middle temperature part of the generator 10, through the GAX 42 and the auxiliary GFD 101 The steel solution is uniformly dispersed in the generator 10 and heat-exchanges with the weak solution flowing in the SHD 12 and then descends.

When the auxiliary GFD 101 is supplied to the upper portion of the annular riser 15, the auxiliary GFD 101 is uniformly dispersed in the generator 10, and the dispersed steel solution flows into the refrigerant vapor And then descends to the lower portion of the generator 10 as the temperature rises.

As described above, the second embodiment of the present invention differs from the first embodiment in that the solution temperature of the SCA 41 outlet is lower than the solution temperature of the outlet of the GAX 42 (about 100 deg. C) ) Can be further lowered.

For example, when ε _main = 0.95 and ε _sub = 0.5 of the GFD 11 and the auxiliary GFD 101 are respectively at the inlet temperature T ₁ = 170 ° C. of the GFD 11, When the temperature T ₂ = 100 ° C, the excess combustion air ratio α = 0.7, and the flame temperature T ₃ = 1400 ° C,

Combustion gas exit temperature of GFD (11) T ₄ appears the same as the equation (10), the flue gas outlet temperature of the auxiliary GFD (101) T ₅ is represented as shown in Equation 13 below.

That is, the temperature of the combustion gas finally discharged from the auxiliary GFD 101 was lowered from 232 ° C to 166 ° C by exchanging the low temperature solution (100 ° C) from the GAX 42 with the combustion gas.

At this time, the improvement effect of the generator thermal efficiency with respect to the conventional cycle shown in FIG. 1 is calculated by Equation (9) as follows.

This increase in thermal efficiency indicates the amount of heat recovery in the auxiliary GFD 101. The flow rate branched to the auxiliary GFD 101 at the outlet of the SCA 41 is determined to be an optimal value through basic experiments.

≪ Third Embodiment >

FIG. 5 shows the ammonia GAX absorption cycle diagram according to the third embodiment of the present invention. The same components as those of the conventional cycle shown in FIG. 1 are denoted by the same reference numerals.

As shown, the generator 10, the condenser 20, the evaporator 30, the absorber 40, the solution pump 50, the refrigerant heat exchanger 60, the GFD 11, the SHD 12, The partial condenser 14, the anaeraser 15, the SCA 41, the GAX 42 and the HCA 43, the SCA 41, the partial condenser 14, And an auxiliary GFD 101 for selectively supplying the upper portion of the SHD 12 and the upper portion of the annular riser 15 by exchanging a part of the steel solution flowing into the GFD 11 with the outlet combustion gas of the GFD 11 Respectively.

The operation and effect of the ammonia GAX absorption cycle according to the third embodiment of the present invention will be described with reference to FIG. 5. The same function as the conventional ammonia GAX absorption cycle shown in FIG. 1 is described in detail Will be omitted.

First, when heat generated from a burner (not shown) is applied to the generator 10, the GFD 11 absorbs heat and a strong solution, which is a working solution in the generator 10, is generated as a refrigerant vapor and a weak solution. The refrigerant vapor is raised in the generator (10).

The chemical solution that has a specific gravity higher than that of the steel solution in the generator 10 is heat exchanged through the SHD 12 and then absorbed by the absorber 10 by the pressure difference between the generator 10, 40, and cooled by passing through the GAX 42, the SCA 41, and the HCA 43 in turn, thereby absorbing the refrigerant vapor. As a result, a steel solution (about 50 ° C) is generated.

On the other hand, the solution of the solution sucked from the lower part of the absorber 40 by the solution pump 50 is supplied into the absorber 40 while being partly condensed by the partial condenser 14 into the solution of about 70 ° C, A part of which is branched and supplied to the auxiliary GFD 101.

The auxiliary GFD 101 then exchanges this river solution with the outlet combustion gas of the GFD 11 to supply it to the top of the anaeraser 15 or to the top of the SHD 12.

Hereinafter, the heat exchange process in the generator 10 is the same as that of the second embodiment described above, so that a description thereof will be omitted.

The third embodiment of the present invention is such that the temperature of the solution at the outlet of the partial condenser 14 is lower than the temperature of the combustion gas passing through the auxiliary GFD 101 at a temperature (about 70 캜) which is much lower than the solution temperature at the inlet of the GFD 11 Can be further lowered.

For example, when ε _main = 0.95 and ε _sub = 0.5 of the GFD 11 and the auxiliary GFD 101 are respectively at the inlet temperature T ₁ = 170 ° C. of the GFD 11, When the temperature T ₂ = 70 ° C, the excess combustion air ratio (α) = 0.7, and the flame temperature T ₃ = 1400 ° C,

The outlet combustion gas temperature T ₄ of the GFD 11 is expressed in the same manner as in Equation (10), and the outlet combustion gas temperature T ₅ of the auxiliary GFD (101) is expressed by the following Equation (15).

That is, the temperature of the combustion gas finally discharged from the auxiliary GFD 101 was lowered from 232 ° C. to 151 ° C. by exchanging the low-temperature solution (70 ° C.) from the partial condenser 14 with the combustion gas.

At this time, the improvement effect of the generator thermal efficiency with respect to the conventional cycle shown in FIG. 1 is calculated as Equation (16) below.

This increase in thermal efficiency indicates the amount of heat recovery in the auxiliary GFD 101. The flow rate branched to the auxiliary GFD 101 at the outlet of the partial condenser 14 is determined to be the optimal value through the basic experiment.

<Fourth Embodiment>

FIG. 6 shows the ammonia GAX absorption cycle diagram according to the fourth embodiment of the present invention. The same components as those of the conventional cycle shown in FIG. 1 are denoted by the same reference numerals.

As shown, the generator 10, the condenser 20, the evaporator 30, the absorber 40, the solution pump 50, the refrigerant heat exchanger 60, the GFD 11, the SHD 12, The partial condenser 14, the anaeraser 15, the SCA 41, the GAX 42 and the HCA 43 in the absorption cycle, An auxiliary GFD 101 for exchanging a part of the steel solution flowing into the GFD 11 with the outlet combustion gas of the GFD 11 to selectively supply the upper part of the SHD 12 and the upper part of the annular riser 15, As shown in FIG.

The operation and effect of the ammonia GAX absorption cycle according to the fourth embodiment of the present invention will be described with reference to FIG. 6. The same function as the conventional ammonia GAX absorption cycle shown in FIG. 1 is described in detail Will be omitted.

First, when heat generated from a burner (not shown) is applied to the generator 10, the GFD 11 absorbs heat and a strong solution, which is a working solution in the generator 10, is generated as a refrigerant vapor and a weak solution. The refrigerant vapor is raised in the generator (10).

The chemical solution that has a specific gravity higher than that of the steel solution in the generator 10 is heat exchanged through the SHD 12 and then absorbed by the absorber 10 by the pressure difference between the generator 10, 40, and dispersed evenly. The GAX 42, the SCA 41, and the HCA 43 are successively subjected to heat exchange with each other to form a strong solution (about 50 ° C).

On the other hand, the solution pump 50 sucks the strong solution from the lower part of the absorber 40 and sprays it to the partial condenser 14. At this time, a part of the strong solution is branched and supplied to the auxiliary GFD 101.

The auxiliary GFD 101 then exchanges this river solution with the outlet combustion gas of the GFD 11 to supply it to the top of the anaeraser 15 or to the top of the SHD 12.

Hereinafter, the heat exchange process in the generator 10 is the same as that of the second and third embodiments described above, so that a description thereof will be omitted.

The fourth embodiment of the present invention is such that the temperature of the solution at the inlet of the partial condenser 14 is lower than the temperature of the combustion gas passing through the auxiliary GFD 101 at a temperature (about 50 캜) which is much lower than the solution temperature at the inlet of the GFD 11 Can be further lowered.

For example, when ε _main = 0.95 and ε _sub = 0.5 of the GFD 11 and the auxiliary GFD 101 are respectively at the inlet temperature T ₁ = 170 ° C. of the GFD 11, When the temperature T ₂ = 50 ° C, the excess combustion air ratio (α) = 0.7, and the flame temperature T ₃ = 1400 ° C,

The outlet combustion gas temperature T ₄ of the GFD 11 is expressed in the same manner as in Equation (10), and the outlet combustion gas temperature T ₅ of the auxiliary GFD (101) is expressed by the following Equation (17).

That is, the temperature of the combustion gas finally exhausted from the auxiliary GFD 101 was lowered from 232 ° C to 141 ° C by exchanging the low-temperature solution (50 ° C) ejected from the solution pump 50 with the combustion gas.

At this time, the improvement effect of the generator thermal efficiency with respect to the conventional cycle shown in FIG. 1 is calculated by Equation (9) as follows.

This increase in thermal efficiency indicates the amount of heat recovery in the auxiliary GFD 101 and the flow rate branched to the auxiliary GFD 101 at the outlet of the solution pump 50 is determined to be an optimal value through basic experiments.

As described above, according to the present invention, the combustion gas that is heat-exchanged with the working solution is heat-exchanged with the working solution, and the temperature of the working solution that is secondarily heat-exchanged is low enough to effectively recover energy from the combustion gas The COP of the cycle is improved by lowering the temperature of the finally discharged combustion gas as much as possible.

Claims (4)

A generator for generating a refrigerant vapor and a refrigerant aqueous solution (weak solution) from the working solution (strong solution) by the heat generated in the burner; a condenser for condensing the refrigerant vapor obtained from the generator with liquid refrigerant using cooling water; An evaporator for evaporating the liquid refrigerant discharged from the evaporator to evaporate the evaporated refrigerant vapor by using cold water whose temperature has risen to make the refrigerant vapor, an absorber for producing a steel solution by continuous absorption action for allowing the weak solution to absorb the refrigerant vapor generated in the evaporator, And a refrigerant heat exchanger for exchanging the refrigerant vapor evaporated in the evaporator with the liquid refrigerant condensed in the condenser, wherein the GFD generating the refrigerant vapor in the generator comprises: And a high-temperature weak solution generated in the GFD, which boils the steel solution supplied from the energizer An anode riser (SHD), an ammonia aqueous solution supplied from a steel solution and a rectifier supplied from the SCH, an aerator for raising the purity of the refrigerant by bringing the aqueous ammonia solution supplied from the generator into contact with a refrigerant vapor boiling in the generator and rising through the SHD, A partial condenser for increasing the purity of the refrigerant vapor by exchanging heat between the steam and the condensed ammonia aqueous solution in the partial condenser to raise the purity of the refrigerant and the refrigerant vapor rising through the steel solution at the outlet of the HCA and the rectifier, (HCA) which removes the absorption heat of the refrigerant vapor and the weak solution and generates a strong solution, and SCA (SCA) which removes the refrigerant vapor and the absorption heat of the weak solution by using the steel solution through the partial condenser as the cooling medium, ) And GAX which removes the absorption heat of the refrigerant vapor and the weak solution supplied from the SHD with the cooling solution of the steel solution whose temperature is increased in the SCA In the comparative ammonia GAX absorption cycle, And an auxiliary GFD (GFD) for exchanging a part of the steel solution with the outlet combustion gas of the GFD and supplying the heat to the generator. Wherein the auxiliary GFD exchanges a part of the steel solution flowing into the upper portion of the SHD via the GAX with the outlet combustion gas of the GFD and supplies the heat to the upper portion of the SHD. The method according to claim 1, Wherein the auxiliary GFD selectively exchanges a part of the river solution flowing into the upper portion of the annularizer through the SCA with the outlet combustion gas of the GFD to selectively supply the upper portion of the SHD and the upper portion of the anode riser, Ammonia Jie X X absorption cycle. The method according to claim 1, Wherein the auxiliary GFD exchanges a part of the steel solution flowing into the SCA through the partial condenser with the outlet combustion gas of the GFD to supply the upper portion of the SHD and the upper portion of the anode riser selectively. Jie X X absorption cycle. The method according to claim 1, Wherein the auxiliary GFD selectively discharges the upper portion of the SHD and the upper portion of the anode riser by exchanging a part of the steel solution injected from the solution pump and flowing into the partial condenser with the outlet combustion gas of the GFD Ammonia Jie X X absorption cycle.