KR20220078253A - Gas heat pump and the control method thereof - Google Patents

Abstract

The present invention relates to an engine operated by combustion; an exhaust pipe connected to the engine and including an inlet pipe part through which exhaust gas discharged from the engine is introduced, and a plurality of branch pipe parts branched from the inlet pipe part; a multi-way valve for controlling the amount of exhaust gas flowing into the branch pipe from the inlet pipe; a plurality of catalytic converters disposed downstream of the plurality of branch pipes, each having a catalyst for purifying the exhaust gas disposed therein; a bypass pipe connecting the plurality of branch pipe parts to each other; an injector for injecting fuel gas and a spark plug for igniting the injected fuel gas, each of which is installed in the plurality of branch pipes; a heat exchanger disposed downstream of the plurality of catalytic converters to exchange heat between the purified air and external air; and an exhaust line for discharging the exhaust gas that has passed through the heat exchanger to the outside.

Description

GAS HEAT PUMP AND THE CONTROL METHOD THEREOF

The present invention relates to a gas heat pump (GHP), and more particularly, to a gas heat pump in which exhaust gas purification and regeneration of a catalytic converter are simultaneously performed by alternately using and regenerating a catalytic converter.

A catalytic converter is disposed downstream of the engine to purify air pollutants contained in exhaust gas discharged from the engine. On the other hand, in the case of a catalyst that adsorbs air pollutants, such as an LNT catalyst, the air pollutant reduction performance is not continuous, and the longer it is used, the significantly deteriorated. To solve this problem, after using the catalyst for a long time, it is necessary to desorb the contaminants adsorbed on the catalyst.

However, when an LNT catalyst is used as a means for reducing air pollutants in a gas heat pump in which the engine is driven at a constant speed for a long time, it is difficult to regenerate the catalyst while maintaining the performance of the gas heat pump without stopping the engine or temporarily overrunning the engine. there is

1. Unexamined Patent Publication No. 10-2017-0043693

An object of the present invention is to provide a gas heat pump that maintains air pollutant reduction performance and cooling/heating performance even when operated at a constant speed for a long time by using and regenerating a plurality of catalytic converters alternately.

Another object of the present invention is to provide a gas heat pump that rapidly regenerates a catalytic converter by utilizing a portion of exhaust gas discharged from an engine for regeneration of the catalytic converter.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A gas heat pump according to an embodiment of the present invention for achieving the above technical problem includes an engine operated by a combustion action, an inlet pipe part connected to the engine and exhaust gas discharged from the engine inlet, and the inlet pipe part An exhaust pipe including a plurality of branch pipe parts branched from, a multi-way valve for controlling the amount of exhaust gas flowing from the inlet pipe part to the branch pipe part, disposed downstream of the plurality of branch pipe parts, each of the exhaust gas inside A plurality of catalytic converters in which a purifying catalyst is disposed, a bypass pipe connecting the plurality of branch pipe parts to each other, an injector for injecting fuel gas installed in each of the plurality of branch pipe parts, and ignition for igniting the injected fuel gas a plug, a heat exchanger disposed downstream of the plurality of catalytic converters to exchange heat between the purified air and external air, and an exhaust line for discharging exhaust gas passing through the heat exchanger to the outside.

In order to achieve the above technical object, a bypass valve is installed in the bypass pipe to close or open the bypass pipe.

In order to achieve the above technical problem, the bypass pipe is arranged in a straight line.

In order to achieve the above technical task, the multi-way valve is disposed at a branch point where the branch pipe part is branched, and controls the inflow of exhaust gas discharged to at least one of a plurality of branch pipe parts or closes at least one branch pipe part .

In order to achieve the above technical problem, an air pollutant sensor is disposed downstream of the plurality of catalytic converters.

In a gas heat pump control method according to an embodiment of the present invention for achieving the above technical problem, the first branch pipe part among the first and second branch pipe parts through which the exhaust gas discharged from the engine passes, and the second branch pipe part Closing step, supplying a portion of the exhaust gas passing through the first branch pipe to the second branch pipe section, the exhaust gas passing through the first branch pipe section is a first catalyst disposed downstream of the first branch pipe section and regenerating a second catalytic converter disposed downstream of the second branch pipe by passing it through a converter for purification, and injecting and burning fuel gas into the second branch pipe.

In order to achieve the above technical problem, the method further includes the step of exchanging the gas passing through the first and second catalytic converters with external air and then discharging the gas to the outside.

In order to achieve the above technical problem, the supplying of a portion of the exhaust gas is supplied through a bypass pipe connecting the first branch pipe part and the second branch pipe part.

In order to achieve the above technical object, the bypass pipe is opened or closed by controlling a bypass valve installed in the bypass pipe.

The gas heat pump according to the embodiment of the present invention can maintain air pollutant reduction performance and air conditioning performance by alternately using and regenerating a plurality of catalytic converters even when the engine is operated for a long time.

In addition, the gas heat pump according to the embodiment of the present invention has an effect of improving fuel efficiency by burning incompletely burned fuel gas by utilizing a portion of exhaust gas for the regeneration action of the catalytic converter.

In addition, the gas heat pump according to the embodiment of the present invention has an effect of rapidly regenerating the catalytic converter by utilizing a portion of the high temperature exhaust gas for the regeneration action of the catalytic converter.

1 is a schematic diagram showing that two catalytic converters purify exhaust gas.
2 is a schematic diagram showing that one catalytic converter purifies exhaust gas and the other catalytic converter is regenerated.
3 is a schematic diagram showing that two catalytic converters are regenerated.
4 is a block diagram of a control method according to an embodiment of the present invention.
5 shows the purification and regeneration process of the LNT catalyst.
6 is a graph showing the composition of exhaust gas according to the air-fuel ratio.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

Terms including an ordinal number such as 1st, 2nd, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

The singular expression may include the plural expression unless the context clearly dictates otherwise.

The plurality of catalytic converters 41 and 42 applied to the gas heat pump according to the embodiment of the present invention are composed of a Lean NOx Trap (LNT) catalyst. In addition to the LNT catalyst, other catalysts may be used.

1 to 3 , a gas heat pump 1 according to an embodiment of the present invention includes an engine 15 operated by combustion; An exhaust pipe including an inlet pipe part 21 connected to the engine 15 and into which the exhaust gas c discharged from the engine 15 flows, and a plurality of branch pipe parts 22a and 22b branched from the inlet pipe part 21 . (20); a multi-way valve 23 for controlling the amount of exhaust gas (c) flowing from the inlet pipe part 21 to the branch pipe parts 22a, 22b; a plurality of catalytic converters (41, 42) disposed downstream of the plurality of branch pipe portions (22a, 22b), each having a catalyst for purifying the exhaust gas (c) disposed therein; a bypass pipe 31 connecting a plurality of branch pipe portions 22a and 22b to each other; Injectors (24a, 24b) for injecting fuel gas (d) and spark plugs (not shown) for igniting the injected fuel gas (d), respectively installed in the plurality of branch pipe parts (22a, 22b); a heat exchanger (60) disposed downstream of the plurality of catalytic converters (41, 42) to exchange heat between purified air and external air; and an exhaust line 70 for discharging the exhaust gas e that has passed through the heat exchanger 60 to the outside.

Upstream of the engine 15 is a filter 11 for filtering foreign substances contained in the outside air, a mixer 12 for mixing the filtered outside air (a) and fuel gas (b) to create a mixer, the engine 15 A valve 13 for controlling the amount of the mixer introduced into the hood and an intake manifold 14 connecting the mixer 12 and the engine 15 may be disposed.

The exhaust gas discharged from the engine 15 is discharged to the inlet pipe 21 along the exhaust manifold 16 , and is introduced into the exhaust pipe 20 through the inlet pipe 21 .

The injector may include a first injector 24a and a second injector 24b. The first injector 24a is installed in the first branch pipe part 22a, and the second injector 24b is installed in the second branch pipe part 22a.

Meanwhile, a spark plug (not shown) may be installed in the plurality of branch pipe portions 22a and 22b to combust the fuel gas d injected from the first and second injectors 24a and 24b. Alternatively, the spark plug (not shown) may be formed by being coupled to the first and second injectors 24a and 24b.

1 is a schematic diagram showing that two catalytic converters 41 and 42 purify the exhaust gas c.

The multi-way valve 23 opens the first and second branch pipe parts 22a and 22b, and the exhaust gas c flows along the first and second branch pipe parts 22a and 22b, respectively, and the first and second branch pipe parts 22a and 22b. 2 It is purified by passing through the catalytic converters (41, 42). Thereafter, it flows into the heat exchanger 60 through the lamination pipe 50 , and heat exchanges with external air in the heat exchanger 60 .

On the other hand, the multi-way valve 23 is disposed at the branch point where the plurality of branch pipe parts (22a, 22b) are branched, and adjusts the inflow amount of exhaust gas discharged to at least any one of the plurality of branch pipe parts (22a, 22b) or at least any One branch pipe portion (22a, 22b) can be closed.

The exhaust gas (e) after heat exchange with the outside air is exhausted to the outside through the exhaust line (70).

An air pollutant sensor 80 may be disposed in the exhaust line 70 . Alternatively, it may be disposed downstream of the plurality of catalytic converters 41 and 42 as well as the exhaust line 70 .

The air pollutant sensor 80 measures the concentration of air pollutants contained in the gas purified by the catalytic converters 41 and 42 .

A bypass valve 32 for closing or opening the bypass pipe 31 may be installed in the bypass pipe 31 . The bypass valve 32 bypasses a part of the exhaust gas inside the first branch pipe part 22a to the second branch pipe part 22b, or a part of the exhaust gas inside the second branch pipe part 22b to the first Bypass to the branch pipe portion (22a).

In the case of FIG. 1 , the bypass valve 32 is locked to block the flow of the exhaust gas c′ to the bypass pipe 31 . The thermal energy of the high-temperature exhaust gas may be lost while flowing through the bypass pipe 31 . To prevent this, the bypass valve 32 is selectively opened when the first and second catalytic converters 41 and 42 perform a purifying action and a regeneration action, respectively.

The bypass pipe 31 may be disposed in a straight line. Since the path of the exhaust gas c' passing through the bypass pipe 31 is shortened, the heat loss of the exhaust gas c' passing through the bypass pipe 31 can be reduced.

On the other hand, FIG. 5 shows the nitrogen oxide (NOx) adsorption and desorption process of the LNT catalyst. When nitrogen oxide passes through the LNT catalyst, it is adsorbed to the LNT catalyst, so that nitrogen oxide is not detected in the exhaust stage.

When carbon monoxide (CO) and hydrocarbons (HC) pass through a state in which nitrogen oxides are adsorbed to the LNT catalyst in large amounts, they react with the nitrogen oxides adsorbed on the LNT catalyst to produce water vapor (H2O), carbon dioxide (CO2), and nitrogen (N2). Non-toxic gas is emitted.

Meanwhile, FIG. 6 shows the components of exhaust gas according to the air-fuel ratio, and the engine 15 is operated by burning the mixer at the air-fuel ratio corresponding to the high-efficiency operation section. However, when the regeneration action of the catalytic converters 41 and 42 is performed, the fuel gas d is injected from the injectors 24a and 24b at an air-fuel ratio corresponding to the regeneration section, and is combusted by a spark plug (not shown).

Accordingly, the engine 15 burns the air-fuel ratio mixture corresponding to the high-efficiency operation section so that nitrogen oxides are included in a large amount in the exhaust gas c.

By burning the fuel gas (d) of the air-fuel ratio corresponding to the regeneration section injected from the injectors (24a, 24b), carbon monoxide and hydrocarbons are included in a large amount in the combustion product.

Accordingly, in the first catalytic converter 41, an exhaust gas purification action of adsorbing nitrogen oxides contained in the exhaust gas c occurs, and in the second catalytic converter 42, a large amount of carbon monoxide and hydrocarbons pass through to convert nitrogen oxides. Regeneration of desorption takes place.

On the other hand, by opening the bypass valve 32 and supplying a part of the exhaust gas c flowing to the first branch pipe part 22a through the bypass pipe 31 to the second branch pipe part 22b, the exhaust It is possible to additionally burn the unburned fuel gas contained in a part of the gas (c).

In addition, by passing the high-temperature exhaust gas c through the second catalytic converter 42, it is possible to shorten the time required to reach the optimum temperature of the catalyst for smooth regeneration.

2 shows that the first catalytic converter 41 performs an exhaust gas purification action, and the second catalytic converter 42 performs a regeneration action.

The multi-way valve 23 is switched so that the first branch pipe part 22a is opened and the second branch pipe part 22b is closed.

The exhaust gas c discharged from the engine 15 is purified by passing through the first catalytic converter 41 along the first branch pipe portion 22a, and the fuel gas d injected from the second injector 24b is It is burned and passed through the second catalytic converter 42 , and the second catalytic converter 42 is regenerated.

3 is a schematic diagram showing that the two catalytic converters 41 and 42 are regenerated.

The fuel gas d is injected from the first and second injectors 24a and 24b, and is combusted by the spark plug (not shown) to regenerate the first and second catalytic converters 41 and 42 .

Referring to Figure 4, the gas heat pump (1) control method according to the embodiment of the present invention, the step of operating the engine 15 by burning the fuel gas (b) (S10), discharged from the engine (15) The step of opening the first branch pipe part 22a among the first and second branch pipe parts 22a and 22b through which the exhaust gas (c) passes and closing the second branch pipe part 22b (S20), the first branch pipe part ( A step (S30) of supplying a part of the exhaust gas (c) passing through 22a) to the second branch pipe part 22b (S30), the exhaust gas (c) passing through the first branch pipe part 22a is the first branch pipe part 22a ) is passed through the first catalytic converter 41 disposed downstream of the and regenerating the second catalytic converter 42 .

The method for controlling the gas heat pump 1 according to the embodiment of the present invention may further include the step of exchanging the gas that has passed through the first and second catalytic converters 41 and 42 with external air and then discharging the gas to the outside. have.

The steps of opening the first branch pipe part 22a and closing the second branch pipe part 22b ( S20 ) may be performed by switching the multi-way valve 23 .

The step (S30) of supplying a portion of the exhaust gas passing through the first branch pipe part 22a to the second branch pipe part 22b is a bypass connecting the first branch pipe part 22a and the second branch pipe part 22b. It may be a step of supplying through the tube (31).

Meanwhile, the gas heat pump control method according to an embodiment of the present invention may further include the step of controlling the bypass valve 32 installed in the bypass pipe 31 to open or close the bypass pipe 31 . have.

On the other hand, in the gas heat pump control method according to the embodiment of the present invention, when the pollutant concentration higher than the reference value is measured by the air pollutant sensor 80 disposed downstream of the first and second catalytic converters 41 and 42, The first branch pipe part 22a may further include opening and closing the second branch pipe part 22b.

The regeneration operation of the catalytic converter may be performed by a user's arbitrary operation, but the regeneration operation of the catalytic converter may be automatically performed by the control unit receiving the sensor information.

Any or other embodiments of the invention described above are not mutually exclusive or distinct. Certain embodiments or other embodiments of the present invention described above may be combined or combined with respective configurations or functions.

For example, it means that configuration A described in a specific embodiment and/or drawings may be combined with configuration B described in other embodiments and/or drawings. That is, even if the coupling between the components is not directly described, it means that the coupling is possible except for the case where it is described that the coupling is impossible.

In the above, preferred embodiments of the present invention have been illustrated and described, but the present invention is not limited to the specific embodiments described above, and in the technical field to which the present invention belongs, without departing from the gist of the present invention as claimed in the claims Various modifications may be made by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

15 : engine
20: exhaust pipe
24 : injector
31: bypass pipe
32: bypass valve
41, 42: first and second catalytic converters
50: paper pipe
60: heat exchanger
70: exhaust line
80: air pollutant sensor

Claims (9)

engines powered by combustion;
an exhaust pipe connected to the engine and including an inlet pipe part through which exhaust gas discharged from the engine is introduced, and a plurality of branch pipe parts branched from the inlet pipe part;
a multi-way valve for controlling the amount of exhaust gas flowing into the branch pipe from the inlet pipe;
a plurality of catalytic converters disposed downstream of the plurality of branch pipes, each having a catalyst for purifying the exhaust gas disposed therein;
a bypass pipe connecting the plurality of branch pipe parts to each other;
an injector for injecting fuel gas and a spark plug for igniting the injected fuel gas, each of which is installed in the plurality of branch pipes;
a heat exchanger disposed downstream of the plurality of catalytic converters to exchange heat between the purified air and external air; and
and an exhaust line for discharging the exhaust gas that has passed through the heat exchanger to the outside. The method of claim 1,
A gas heat pump including a bypass valve installed on the bypass pipe to close or open the bypass pipe. The method of claim 1,
The bypass pipe is a gas heat pump disposed in a straight line. The method of claim 1,
The multi-way valve is disposed at a branch point where the branch pipe is branched, and controls the inflow of exhaust gas discharged to at least one of a plurality of branch pipe parts or closes at least one branch pipe part. The method of claim 1,
A gas heat pump in which an air pollutant sensor is disposed downstream of the plurality of catalytic converters. operating an engine by burning fuel gas;
opening a first branch pipe part among first and second branch pipe parts through which the exhaust gas discharged from the engine passes and closing a second branch pipe part;
supplying a portion of the exhaust gas passing through the first branch pipe to the second branch pipe;
The exhaust gas passing through the first branch pipe is purified by passing through a first catalytic converter disposed downstream of the first branch pipe, and fuel gas is injected and combusted into the second branch pipe to be burned downstream of the second branch pipe. Gas heat pump control method comprising a; regenerating the second catalytic converter disposed in the. 7. The method of claim 6,
The gas heat pump control method further comprising the step of exchanging the gas passing through the first and second catalytic converters with external air and then discharging to the outside. 7. The method of claim 6,
In the step of supplying a portion of the exhaust gas, the gas heat pump control method is supplied through a bypass pipe connecting the first branch pipe part and the second branch pipe part. 9. The method of claim 8,
and controlling a bypass valve installed in the bypass pipe to open or close the bypass pipe.

Images