KR102151468B1 - Water supply temperature maintenance system of industrial condensing boiler - Google Patents

Abstract

The present invention relates to a system for maintaining a water supply temperature of an industrial condensing boiler, and more specifically, to a system for maintaining a water supply temperature of an industrial condensing boiler, including: a boiler; a water supply tank for supplying hot water to the boiler; an economizer for supplying hot water heated by heat exchange with exhaust gas discharged by the boiler to the boiler or a water supply tank; a raw water supply unit for supplying raw water to the water supply tank or the economizer; a condensed water supply unit for supplying condensed water discharged from the boiler to the water supply tank; and a control unit for controlling the supply of hot water to the boiler from the water supply tank or the economizer according to the flow rate and temperature of the water supply tank. According to the present invention, suggested is the system for maintaining a water supply temperature of an industrial condensing boiler, which recovers high-temperature condensed water that is discarded in an industrial field and uses the condensed water for water supply, collects exhaust gas that is discarded at the same time, preheats or increases the water supply temperature in the economizer to continuously maintain the water supply temperature above a certain level, thereby maximizing the efficiency of the boiler.

Description

Water supply temperature maintenance system of industrial condensing boiler}

The present invention recovers high-temperature condensate that is thrown away in industrial sites and uses it for water supply, and at the same time recovers exhaust gas that is discarded and preheats or raises the water supply temperature in an economizer to continuously maintain a water supply temperature above a certain level. It relates to a water supply temperature maintenance system for industrial condensing boilers that can maximize

Typically, a boiler has a structure to maximize thermal efficiency by absorbing sensible heat and latent heat of condensation of exhaust gas as useful heat.

In particular, the condensing boiler maximizes this and represents a high-efficiency boiler.

As a conventional technology for such a condensing boiler, there is a structure that maximizes thermal efficiency by installing double economizers, which is driven by connecting two economizers in series on the exhaust gas discharge path of the boiler body, and the hot water temperature and exhaust in the hot water tank. By selectively controlling the path of the fluid to recover sensible heat of exhaust gas and latent heat of condensation from the two economizers according to the discharge temperature of the gas, the effect of supplying low temperature water to the economizer with a large surface area by adapting to the operating state of the boiler is achieved. It is constructed so that the thermal efficiency can be further increased by attempting.

However, the prior art as described above generates hot water through heat exchange between exhaust gas and water using two economizers, but it is disadvantageous in terms of cost because a plurality of economizers, which is a kind of heat exchanger, must be installed.

In particular, among industrial boilers, pipe boilers or furnace pipe boilers produce energy using hot water or steam, and most of the condensate generated from the steam is discarded through the drain line. When it is used for water supply, not only energy saving efficiency but also boiler efficiency can be maximized.

However, in the case of condensing boilers including the prior art, the case of using for water supply by recirculating discarded condensate has not yet been developed. Therefore, the development of a technology that utilizes discarded condensate as feed water at the same time as the conventional economizer is a highly efficient boiler. Can advance the development of

Republic of Korea Patent Registration No. 10-1243698 (published on March 08, 2013)

The present invention was devised to solve the above problems,

To maximize the efficiency of the boiler by recovering the high-temperature condensate that is discarded in industrial sites and using it for water supply, and by recovering the exhaust gas that is discarded at the same time, preheating or raising the water supply temperature in the economizer to continuously maintain the water supply temperature above a certain level. To do it for one purpose.

The system for maintaining the water supply temperature of the industrial condensing boiler according to the present invention comprises: a boiler; A water supply tank for supplying hot water to the boiler; An economizer for supplying hot water heated by heat exchange with the exhaust gas discharged by the boiler to the boiler or the feed water tank; A raw water supply unit for supplying raw water to the water supply tank or the economizer; A condensed water supply unit for supplying the condensed water discharged from the boiler to the feed water tank; And a control unit for controlling the supply of hot water from the water supply tank or the economizer to the boiler according to the flow rate and temperature of the water supply tank.

A first valve for opening and closing the supply of raw water from the raw water supply unit to the feed water tank according to the present invention, a second valve for opening and closing hot water supply from the feed water tank to the boiler, and hot water supply from the feed water tank to the economizer A third valve for opening and closing, a fourth valve for opening and closing the supply of raw water heat-exchanged from the economizer to the boiler, a fifth valve for opening and closing the supply of raw water from the raw water supply unit to the economizer, and from the economizer It characterized in that it is provided with a sixth valve for opening and closing the hot water supply heat exchanged to the water supply tank.

The control unit according to the present invention opens the second valve, the fifth valve and the sixth valve when the flow rate and temperature of the water supply tank is greater than or equal to a set value, and at the same time, the first valve, the third valve and the It is characterized in that the control to close the fourth valve to form a first water supply line.

In the first water supply line according to the present invention, condensed water is supplied from the condensed water supply unit to the water supply tank, raw water is supplied from the raw water supply unit to the economizer, and the raw water heat exchanged with exhaust gas through the economizer is the water supply tank It is supplied to, and the feed water tank is characterized in that supplying the raw water heat-exchanged with condensed water to the boiler.

When the flow rate and temperature of the water supply tank are less than or equal to a set value, the control unit according to the present invention opens the first valve, the third valve and the fourth valve, and at the same time, the second valve, the fifth valve, and the It is characterized in that the control to close the sixth valve to form a second water supply line.

In the second water supply line according to the present invention, condensed water is supplied from the condensed water supply unit to the water supply tank, raw water is supplied from the raw water supply unit to the water supply tank, and condensed water and raw water are supplied from the water supply tank to the economizer, The economizer is characterized in that supplying condensed water and raw water heat-exchanged with exhaust gas to the boiler.

A PT sensor for measuring the temperature of the water supply tank according to the present invention is provided, and a level gauge for measuring the flow rate of the water supply tank is provided.

The water supply temperature maintenance system of an industrial condensing boiler according to the present invention can smoothly use the condensed water by using the high-temperature condensed water that is discarded as water supply, and at the same time maximize the effect of the economizer.

In addition, according to the present invention, it is easy to increase the water supply temperature by using a water supply having an elevated temperature and a high temperature condensed water together through an economizer, and a stable boiler water supply can be expected.

In addition, the present invention can shorten the preheating time of the water supply temperature at the initial stage of operation of the boiler, and can continuously maintain the water supply temperature at a temperature higher than a certain level, thereby reducing fuel consumption.

1 is a conceptual diagram showing a water supply temperature maintenance system of an industrial condensing boiler according to the present invention,
2 is a control flow diagram showing the water supply temperature maintenance system according to the present invention,
3 is a conceptual diagram showing a first water supply line of the water supply temperature maintenance system according to the present invention,
4 is a conceptual diagram showing a second water supply line of the water supply temperature maintenance system according to the present invention.

In order to explain the present invention and the operational advantages of the present invention and the object achieved by the implementation of the present invention, the following describes a preferred embodiment of the present invention and looks at it with reference.

First, terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention, and expressions in the singular may include a plurality of expressions unless clearly differently in context. In addition, in the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or a combination thereof described in the specification, but one or more other It is to be understood that the presence or addition of features, numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance the possibility of being excluded.

In describing the present invention, when it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present invention, a detailed description thereof will be omitted.

1 to 4, the system for maintaining the water supply temperature of the industrial condensing boiler according to the present invention includes a boiler 10, a water supply tank 20 for supplying hot water to the boiler 10, and an economizer 30. And, it is configured to include a raw water supply unit 40, a condensed water supply unit 50 and a control unit (not shown).

1 to 4, the boiler 10 according to the present invention is composed of a combustion chamber having a fire tube, a water drum formed around the combustion chamber and filled with water, and a burner installed at the entrance of the combustion chamber to generate flame. . The exhaust gas generated by the flame thus generated heats the water filled in the water drum or generates steam while passing through the pipe through the discharge passage. At this time, the exhaust gas is discharged through the flue if it passes through the pipe, but in the condensing boiler according to the present invention, the discharged exhaust gas is not immediately discharged through the flue, and water supplied to the economizer 30 through the economizer 30 and It is configured to generate hot water at a predetermined temperature through heat exchange and then discharge through the flue. This can increase energy efficiency in that the exhaust gas emitted after combustion is not discarded as it is but utilized.

The boiler 10 configured as described above is provided with a first inlet 11 for water supply in a water supply pipe to supply water to a water drum.

In this case, when the water supplied to the first inlet 11 is heated to a predetermined temperature and supplied, the thermal efficiency can be improved. To this end, the raw water is heated to a constant temperature and supplied with water, as well as by generating drainage from the generated steam. ) If the high-temperature condensed water is recovered and used to supply the water to the boiler 10, the thermal efficiency can be maximized.

Therefore, in the present invention, it is intended to ensure stable efficiency of the boiler 10 by supplying raw water or condensed water heated to a constant temperature according to the flow rate of the water supply tank 20 and the temperature of the water through different water supply lines.

Meanwhile, the boiler 10 according to the present invention can be applied as it is to the furnace tube boiler as well as the tube boiler 10 as described above.

As described above, the water supplied to the boiler 10 according to the present invention is from the raw water supply unit 40 for supplying the raw water passed through the water softener, and the condensate supply unit 50 for recovering and supplying the condensed water drained. Is supplied.

In this way, the raw water and condensed water supplied from the raw water supply unit 40 and the condensed water supply unit 50 are supplied to the water supply tank 20 to the economizer 30, and the supply of the raw water and the condensate water depends on the flow rate and temperature of the water supply tank 20. It is supplied to the water supply tank 20 or the economizer 30 and is supplied to the first inlet 11 of the boiler 10.

First, the water supply tank 20 is provided with a second inlet 21 through which the raw water supplied from the raw water supply unit 40 is introduced, and a third inlet 23 through which the condensed water supplied from the condensate water supply unit 50 flows in. , A fourth inlet 25 through which hot water heated from the economizer 30 flows is provided. In addition, a first for supplying hot water to the water supply tank 20 to the first inlet 11 of the boiler 10 or for supplying condensed water or raw water having a relatively low temperature, that is, less than a set temperature, to the economizer 30. An outlet 27 is provided.

Next, the economizer 30 is provided with a fifth inlet 31 through which condensed water or raw water supplied from the water supply tank 20 or raw water supplied from the raw water supply unit 40 is introduced, and through the fifth inlet 31 The supplied condensed water, raw water, or raw water is provided with a second outlet 33 that is discharged as warm water through heat exchange with exhaust gas.

In addition, the first valve (V1) to the sixth valve (V6) are provided on the water supply line to open and close the water supply line. Hereinafter, the arrangement structure of the valve on the water supply line will be described.

First, the first valve V1 is disposed on the first line L1 for supplying raw water from the raw water supply unit 40 to the second inlet 21 of the water supply tank 20, and the second valve V2 is It is disposed on the second line L2 for supplying hot water from the first outlet 27 of the water supply tank 20 to the first inlet 11 of the boiler 10. In addition, the third valve V3 is disposed on the third line L3 for supplying condensed water or raw water from the first outlet 27 of the water supply tank 20 to the fifth inlet 31 of the economizer 30, and , The fourth valve V4 is disposed on the fourth line L4 for supplying heat-exchanged raw water from the second outlet 33 of the economizer 30 to the first inlet 11 of the boiler 10. In addition, the fifth valve (V5) is disposed on the fifth line (L5) for supplying raw water from the raw water supply unit (40) to the fifth inlet (31) of the economizer (30), and the sixth valve (V6) is the economizer. It is disposed on the sixth line (L6) for supplying the heat-exchanged hot water from the second outlet 33 of (30) to the fourth inlet (25) of the water supply tank (20).

In this case, it is preferable that each valve is provided as an electromagnetic valve and is configured to enable open/close control.

Next, the first pump 80 for supplying hot or cold water discharged from the water supply tank 20 at a constant pressure is on the discharge line from the first outlet 27 of the water supply tank 20 (the second line ( L2) to the third line (L3)), the second pump 90 for supplying the raw water supplied from the raw water supply unit 40 to the economizer 30 at a constant pressure is on the fifth line (L5). Is placed in

In this case, the first pump 80 is always operated when the boiler 10 is operated, and whether or not the second pump 90 is operated is determined by water supply control according to the flow rate and temperature of the water supply tank 20 to be described later.

In the water supply temperature maintenance system according to the present invention configured as described above, the opening and closing of each valve is controlled by the control unit, and hot water of a constant temperature is always supplied to the boiler 10 through the water supply line formed therethrough. The water supply line is determined by the control unit according to the flow rate and temperature of the water supply tank 20 set in advance.

In this case, in order to measure the flow rate and temperature of the water supply tank 20, the water supply tank 20 is provided with a level gauge 70 for measuring the flow rate, and discharge through the water supply tank 20 or the first outlet 27 A PT sensor 60 is installed on the line to measure the temperature of hot water inside or discharged from the water supply tank 20.

First, as shown in FIGS. 2 and 3, when the flow rate and temperature of the water supply tank 20 are higher than the set value only with the condensed water supplied from the condensate water supply unit 50, as well as the flow rate of the water supply tank 20, the water supply temperature is This is the case where the boiler 10 has a sufficient temperature to supply.

At this time, the control unit opens the second valve (V2), the fifth valve (V5) and the sixth valve (V6), and at the same time closes the first valve (V1), the third valve (V3) and the fourth valve (V4). Thus, a first water supply line is formed. Here, in the illustration of FIG. 3, the first water supply line is indicated by a dotted line.

That is, since the first water supply line has a sufficient temperature for supplying water from the water supply tank 20 to the boiler 10 and the flow rate is sufficient, the second valve V2 on the second line L2 is opened to open the water supply tank ( Hot water is supplied from the first outlet 27 of 20) to the first inlet 11 of the boiler 10. In this case, the raw water is not directly sent to the water supply tank 20, but the fifth valve V5 on the fifth line L5 is opened and supplied to the economizer 30, and then the sixth valve on the sixth line L6 ( V6) is opened to supply hot water heated to a constant temperature to the water supply tank 20.

In this case, the second pump 90 is operated to directly supply raw water to the economizer 30.

The first water supply line as described above is composed of a second line L2, a fifth line L5, and a sixth line L6.

Next, as shown in FIGS. 2 and 4, when the flow rate and temperature of the water supply tank 20 are less than or equal to the set value, only the condensed water supplied from the condensate water supply unit 50 is not only the flow rate of the water supply tank 20, but also the water supply temperature. This is the case in which the boiler 10 does not have a sufficient temperature to supply.

At this time, the controller opens the first valve V1, the third valve V3 and the fourth valve V4, and closes the second valve V2, the fifth valve V5, and the sixth valve V6. A second water supply line is formed. Here, in the illustration of FIG. 4, the second water supply line is indicated by a dotted line.

That is, in the second water supply line, only the condensed water supplied to the water supply tank 20 is not sufficient temperature of hot water to be supplied from the water supply tank 20 to the boiler 10, and the flow rate is not sufficient, so from the condensed water supply unit 50 The raw water is supplied to the water supply tank 20 by opening the first valve V1 on the first line L1 and supplying the raw water to the water supply tank 20 at the same time as the condensed water is supplied directly to the water supply tank 20, and then on the third line L3. By opening the third valve (V3), raw water and condensed water are mixed and supplied to the economizer 30, and the condensed water and raw water from the economizer 30 are heated through heat exchange with exhaust gas. The fourth valve V4 is opened to supply hot water to the first inlet 11 of the boiler 10.

In this case, since the raw water is supplied to the water supply tank 20, the second pump 90 is not operated.

The second water supply line as described above includes a first line L1, a third line L3, and a fourth line L4.

In addition, as described above, the control unit measures the flow rate and the water supply temperature of the water supply tank 20 by the level gauge 70 and the PT sensor 60 in real time during the operation of the first water supply line and the second water supply line, and The flow rate and water supply temperature are compared with the set value and the water supply line is determined according to the comparison value, thereby maintaining a constant water supply temperature and supplying hot water.

In this case, the flow rate of the water supply tank 20 is insufficient, but the water supply temperature of the water supply tank 20 is higher than the set value, or the flow rate of the water supply tank 20 is sufficient, but the water supply temperature of the water supply tank 20 is less than the set value. There may be cases.

In this case, the control unit may individually control each valve.

For example, as in the former, when the flow rate of the water supply tank 20 is insufficient and the water supply temperature is higher than the set value, the insufficient flow rate is directly supplied with condensed water at a constant temperature from the condensate supply unit 50, and the raw water is connected to the fifth line (L5). It is possible to control to be supplied to the water supply tank 20 through the sixth line L6. In this case, the hot water in the water supply tank 20 is directly supplied from the water supply tank 20 to the boiler 10 through the second line L2.

In the latter case, condensed water or raw water having a low temperature in the feedwater tank 20 is supplied to the economizer 30 through the third line L3, and the boiler 10 from the economizer 30 through the fourth line L4. ) Can be controlled so that hot water is directly supplied. In this case, the supply of condensed water and raw water may be stopped or selectively supplied until the control conditions are satisfied.

As described above, the present invention has been described with reference to an embodiment shown in the drawings, but this is only an example, and various modifications and other equivalent embodiments are possible from those of ordinary skill in the art. Will understand.

Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

V1 ~ V6: 1st valve ~ 6th valve
L1 ~ L6: 1st line ~ 2nd line
10: boiler
11: first entrance
20: water supply tank
21: second entrance 23: third entrance
25: fourth entrance 27: first exit
30: Economizer
31: 5th entrance 33: 2nd exit
40: raw water supply unit
50: condensate supply unit
60: PT sensor
70: level gauge
80: first pump
90: second pump

Claims (7)

delete Boiler 10;
A water supply tank 20 for supplying hot water to the boiler 10;
An economizer 30 for supplying hot water heated by heat exchange with exhaust gas discharged by the boiler 10 to the boiler 10 or the feed water tank 20;
A raw water supply unit 40 for supplying raw water to the water supply tank 20 or the economizer 30;
A condensed water supply unit 50 for supplying the condensed water discharged from the boiler 10 to the feed water tank 20; And
A controller for controlling the supply of hot water from the water supply tank 20 or the economizer 30 to the boiler 10 according to the flow rate and temperature of the water supply tank 20;
Including,
A first valve (V1) for opening and closing the supply of raw water from the raw water supply unit 40 to the water supply tank 20,
A second valve (V2) for opening and closing the supply of hot water from the water supply tank 20 to the boiler 10,
A third valve (V3) for opening and closing the supply of low temperature water from the water supply tank 20 to the economizer 30,
A fourth valve (V4) for opening and closing the supply of raw water heat exchanged from the economizer 30 to the boiler 10,
A fifth valve (V5) for opening and closing the supply of raw water from the raw water supply unit 40 to the economizer 30,
A water supply temperature maintenance system for an industrial condensing boiler, characterized in that a sixth valve (V6) is provided for opening and closing the supply of hot water exchanged from the economizer (30) to the water supply tank (20).
The method of claim 2,
When the flow rate and temperature of the water supply tank 20 are greater than or equal to a set value,
The second valve (V2), the fifth valve (V5), and the sixth valve (V6) are opened, and the first valve (V1), the third valve (V3) and the fourth valve (V4) are opened. ) To form a first water supply line by controlling to close the water supply temperature maintenance system of an industrial condensing boiler.
The method of claim 3, wherein the first water supply line
Condensed water is supplied from the condensed water supply unit 50 to the water supply tank 20,
Raw water is supplied from the raw water supply unit 40 to the economizer 30,
Raw water heat-exchanged with exhaust gas through the economizer 30 is supplied to the water supply tank 20,
The feed water tank (20) is a water supply temperature maintenance system for an industrial condensing boiler, characterized in that supplying the raw water heat exchanged with the condensed water to the boiler (10).
The method of claim 2,
When the flow rate and temperature of the water supply tank 20 are less than or equal to a set value,
The first valve (V1), the third valve (V3), and the fourth valve (V4) are opened, and at the same time, the second valve (V2), the fifth valve (V5), and the sixth valve (V6) are opened. ) To form a second water supply line by controlling to close the water supply temperature maintenance system of an industrial condensing boiler.
The method of claim 5, wherein the second water supply line
Condensed water is supplied from the condensed water supply unit 50 to the water supply tank 20,
Raw water is supplied from the raw water supply unit 40 to the water supply tank 20,
Condensed water and raw water are supplied from the water supply tank 20 to the economizer 30,
The economizer (30) supplies the condensed water and raw water heat-exchanged with exhaust gas to the boiler (10).
The method according to any one of claims 2 to 6,
A PT sensor 60 for measuring the temperature of the water supply tank 20 is provided,
A water supply temperature maintenance system of an industrial condensing boiler, characterized in that a level gauge (70) for measuring the flow rate of the water supply tank (20) is provided.

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