JPH09236208A - Fluid-feeding device in combined multiboilers system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen in number the fluid-feeding devices which in feeding a fluid, such as water, fuel, or air for combustion, have been necessary individually for boilers so that the cost of the system as a whole can be lowered. SOLUTION: Each of boilers 1 is connected to a win fluid-feeding line 10 with a control valve 13 in the connection line. A fluid-feeding device 12 is connected with the main fluid-feeding line 10 and a pressure-controlling device 14 for keeping constant the fluid pressure in the main fluid-feeding line 10 on the discharge side of the fluid-feeding device 12 is provided. By opening or closing control of a control valve 13 belonging to the boiler 1 at work a fluid fed thereto is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid supply device in a boiler multi-can installation system.
The fluid referred to here is feed water supplied to the boiler, or combustion air or fuel (liquid fuel or gas fuel) supplied to the burner of the boiler.

[0002]

2. Description of the Related Art As is well known, a multi-can installation system for a boiler is to install a plurality of boilers, install a pressure detector on a steam header common to those boilers, and grasp the load condition to determine the load amount. In order to follow the load, the required number of units are sequentially switched to combustion according to the preset starting order according to the above, and if there is a load change, the boiler is burned and stopped according to the load change. Is.

In the multi-can installation system, each boiler is individually supplied with water, combustion air, and fuel, so that each boiler requires a water supply pump, a blower, and a fuel pump.

Further, in the case where the water supply tank and the fuel tank common to the whole multi-can installation system are provided, the distance between the water supply tank and the fuel tank and the water supply pump of each boiler or the fuel pump becomes long. When the pressure loss on the suction side of each water supply pump or fuel pump of each boiler increases, the water supply pump or fuel pump of each boiler cannot sufficiently suck water or fuel to supply it to the boiler. Therefore, it is necessary to make the suction side pipe of each pump thick to reduce the pressure loss and to provide an auxiliary pump on the tank side. In particular, when aerial piping is used and liquid is sent from the water tank or fuel tank to the boiler side, a suction pumping height corresponding to the height from the tank liquid level to the aerial piping is required. It was difficult to suck the liquid only with the fuel pump, and it was necessary to pump the liquid by using an auxiliary pump or the like. The aerial piping referred to here is a piping connected to the tank at a position higher than the tank liquid level.

That is, in the conventional system, in addition to a water supply pump, a fuel pump, a blower, etc., each boiler requires electric wiring and the like, which causes the system to become complicated and costly.

[0006]

The problems to be solved by the present invention were individually required in such a boiler multi-can installation system in order to supply fluids such as water supply, fuel and combustion air. The object is to reduce the number of fluid supply devices and suppress an increase in the cost of the entire system.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a fluid supply device for a multi-can installation system of a boiler, which is low in cost and has a simplified structure. Specifically, in a boiler multi-can installation system in which multiple boilers are installed and the number of operating boilers is controlled according to the load amount, each boiler is connected to the main fluid supply route via a control valve. In addition, a fluid supply device is connected to the fluid supply main route, and pressure control means for maintaining a constant fluid pressure in the fluid supply main route on the discharge side of the fluid supply device is provided, which corresponds to a boiler in operation. By controlling the opening and closing of the control valve, the supply of fluid to each boiler is controlled.

Further, according to the present invention, each boiler is connected to a fluid supply main path through a constant flow control valve, and a fluid supply device which is activated when the boiler is operated is connected to the fluid supply main path to operate the boiler. The supply of fluid to each boiler is controlled by controlling the opening and closing of the constant flow rate control valve corresponding to the boiler.

According to the above construction, among the control valves connected to each boiler, the control valve corresponding to the operating boiler is opened to supply an appropriate amount of fluid to each boiler.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The embodiment of the present invention is applied to a multi-can installation system for boilers in which a plurality of boilers are installed and the number of operating boilers is controlled according to the load amount. Each of them is connected to a fluid supply main path via a control valve, a fluid supply apparatus is connected to the fluid supply main path, and the discharge pressure of the fluid supply apparatus in this fluid supply main path is kept constant by the pressure control means. In this way, by controlling the opening of the control valve corresponding to the operating boiler, an appropriate amount of fluid is supplied to each boiler.

The multi-can installation system referred to here is equipped with a so-called automatic number control device for detecting the load on the boiler and automatically determining and controlling the number of operating boilers according to the load. Not only the installation system, but also the load of the boiler is detected by a person, and a multi-can installation system in which the number of boilers to be operated is determined and operated according to the load is included. The boiler here includes not only a steam boiler but also a hot water boiler. Further, in the present invention, the means for controlling the discharge side pressure of the water supply pump to be constant is connected to an inverter device for controlling the discharge side pressure to be constant by increasing or decreasing the number of revolutions of the pump, and to the discharge side piping It also includes a constant pressure control valve that keeps the pressure on the downstream side constant. Further, the opening / closing control of the control valve corresponding to the boiler in operation includes not only the control device of the boiler itself but also the automatic unit control device.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to water as a fluid, that is, a water supply system will be described below with reference to FIG.
1 is a drawing for explaining the piping system of the first embodiment of the present invention.

In the drawing, a plurality of boilers (1) are installed (four in the illustrated embodiment), and each boiler (1) is provided with a combustion device (2) for heating. Each boiler (1) is connected to a common steam header (3) via a steam pipe (4). The steam header (3) is provided with a pressure detector (5) for detecting the internal steam pressure.

The unit number control device (6) uses the pressure detector (5).
Combustion / stop of each boiler (1) is controlled on the basis of the pressure detection signal of (1). At this time, the starting order of each boiler (1) follows the preset order. Further, each boiler (1) is equipped with an operation control device (7), and combustion control, safety control, water supply control, etc. of each boiler (1) are individually performed by this operation control device (7). .

Each boiler (1) is connected to a water supply line (10) extending from a water supply tank (9) via a water supply branch pipe (11), and the upstream side of this water supply line (10). A water supply pump (12) is connected to the. Therefore, each boiler
The water supply to (1) is performed by the water supply pump (12) connected to the upstream side of the water supply line (10) from the water supply line (10) to the water supply branch pipe (11) corresponding to each boiler (1). ) Via. Furthermore, from this water supply line (10)
A water supply control valve (13) is installed in the water supply branch pipe (11) that branches into (1), and each water supply control valve (13) is equipped with a water level detector (not shown) installed in each boiler (1). Control) by the operation control device (7) based on the water level detection signal of
The on-off control is performed so that the water level in the can is almost constant. This first embodiment shows an embodiment applied to a water supply system, and therefore the main fluid supply route is the water supply line.
(10), the fluid supply device connected to this fluid supply main path is the water supply pump (12), and the control valve connected between the fluid supply main path and each boiler (1) is the water supply control Valve (13)
It is.

Further, the water supply line (10) is provided with a pressure adjusting device (14) for controlling the pressure in the water supply line (10) on the discharge side of the water supply pump (12) to be constant. The pressure adjusting device (14) in the first embodiment comprises a pressure detector (15) for detecting the pressure on the discharge side of the water supply pump (12) in the water supply line (10) and the output of this pressure detector (15). And a control circuit (16) for controlling the rotation speed of the water supply pump (12) based on the above. The control circuit (16) contains an inverter circuit for controlling the rotation speed of the water supply pump (12). Further, the operation / stop of the water supply pump (12) is performed by the unit control device (6), and the fuel control valves (25) and the water supply control valve (13) are operated by the operation control device of the corresponding boiler (1). Perform according to (7).

In the above structure, the water supply pump (12)
Is activated at the start of operation of the entire multi-can installation system, and is controlled by the pressure adjusting device (14) so that the pressure on the discharge side in the water supply line (10) becomes constant. Then, according to the load request to the multi-can installation system, a predetermined number of boilers
When the operation of (1) is started, the water supply control valve (13) is opened by the operation control device (7) of each boiler (1) in the operating state. Here, each water supply control valve (13), since the pressure of the upstream water supply line (10), that is, the discharge side pressure of the water supply pump (12) is controlled to be constant, the water supply control valve (13) Water is supplied corresponding to the opening time, and therefore the operation control device
The water level control by (7) is also performed reliably.

When the water supply line (10) has the above-mentioned overhead piping section (10 '), the water supply tank (9) at the upstream side of this overhead piping section (10'). Since water as a fluid is pumped by the water supply pump (12) provided on the side, there is no pressure loss on the suction side of the water supply pump (12) due to this overhead piping (10 '), and the water supply It is not necessary to consider the suction head of the pump (12). Further, by using such an overhead piping section (10 ') as the discharge side of the water supply pump (12), it is not necessary to vent the air inside the overhead piping section (10').

In the first embodiment, the water supply pump (12) as the fluid supply device is illustrated as one unit, but when the fluid supply device is stopped at the time of maintenance or the like, or when there is a failure or the like. In consideration of the case where it stops in some cases, it is preferable to provide an auxiliary fluid supply device.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. Incidentally, FIG. 2 shows a second embodiment of the present invention.
It is drawing for demonstrating the piping system of an Example. The second embodiment shows an embodiment in which the present invention is applied to a combustion system. In this combustion system, fuel (gas fuel,
Liquid fuel) and combustion air are supplied. Therefore, the main fluid supply route in this second embodiment is the fuel supply line (20) and the air supply line (21). That is, as in the first embodiment, the combustion device (2) of each boiler (1) extends from the fuel tank (22) to the fuel supply line (20) equipped with the fuel pump (23) on the way. Each fuel branch pipe (24) is connected via a branch pipe (24).
5) is connected. Further, each combustion device (2) is connected to the air supply line (21) extending from the blower (26) through an air branch pipe (27), and this air branch pipe (27) is An air control valve (28) such as a deadline damper is connected. That is, in the second embodiment, the main fluid supply route in the fuel system is the fuel supply line (20), and the fluid supply device is connected to the fuel pump (2) connected to the upstream side of the fuel supply line (20).
3), and the control valve between the main fluid supply path and each boiler (1) is the fuel control valve (25). The main fluid supply route in the combustion air system is the air supply line (21), the fluid supply device is the blower (26) connected to the upstream side of the air supply line (21), and the fluid supply main route and each The control valve to and from the boiler (1) is the air control valve (28). Further, each fluid supply main path is provided with a pressure adjusting device for controlling the pressure in the fluid supply main path on the discharge side of each fluid supply apparatus to be constant. That is, the fuel pump (23) is connected to the fuel supply line (20).
A fuel pressure adjusting device (29) is provided to control the pressure in the fuel supply line (20) on the discharge side of the air supply line (21), and the air supply line (21) includes air on the discharge side of the blower (26). An air pressure adjusting device (30) for controlling the pressure in the supply line (21) to be constant is provided. The fuel pressure adjusting device (29) and the air pressure adjusting device (30) in the second embodiment have the same configurations as in the first embodiment, and the fuel pressure adjusting device
(29) is a fuel pressure detector (31) for detecting the discharge side pressure of the fuel pump (23) in the fuel supply line (20), and the fuel pump based on the output of this fuel pressure detector (31) (twenty three)
And a control circuit (32) for controlling the number of rotations of the air pressure adjusting device (30), the air blower in the air supply line (21).
An air pressure detector (33) that detects the discharge side pressure of (26),
Based on the output of the air pressure detector (33), the blower (2
6) and a control circuit (34) for controlling the rotation speed. Each of the control circuits (32) and (34) includes an inverter circuit for controlling the rotation speed of the fuel pump (23) and the blower (26). Further, the fuel pump (23) and the blower (26) are operated / stopped by the unit control device (6), and each fuel control valve (25) and air control valve (28) respectively corresponds to the boiler ( This is performed by the operation control device (7) in 1). Also in the second embodiment, as described above, by controlling the opening and closing of the fuel control valve (25) and the air control valve (28) corresponding to the operating boiler (1), the combustion device of each boiler (1) is controlled. Supply fuel and combustion air to (2).

Here, each boiler (1) or a part of the boilers
The combustion device (2) of (1) is not the on-off control (two-position control) as described above, but each boiler (1) or a part of the boilers (1) has three-position control. In the case of controlling at three control positions of high combustion amount, low combustion amount, and stop, for high combustion and low combustion on the downstream side (that is, the boiler side) of the fuel control valve (25). 2 fuel passages are formed, and control valves for high combustion and low combustion are connected to each fuel passage, and each control valve is selected by the operation control device (7) on the side of the boiler (1). The fuel supply amount is switched by controlling the opening and closing of the fuel. On the other hand, regarding the adjustment of the combustion air at this time, a flow control means such as a damper is provided on the downstream side of the air control valve (28), and the flow control means is used for the boiler.
The air supply amount may be adjusted by controlling the opening and closing by the operation control device (7) on the (1) side.

Next, the third embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. Incidentally, FIG. 3 shows the third embodiment of the present invention.
It is drawing for demonstrating the piping system of an Example. In the third embodiment, the pressure on the discharge side is made constant by controlling the fluid supply device as in the first and second embodiments, but instead between each boiler and the main fluid supply route. At the entrance of the control valve, a constant flow valve that controls the flow rate at a constant rate is used. The third embodiment is applied to a water supply system as in the first embodiment, and specifically, from the water supply line (10) to the water supply branch pipes (11) corresponding to the respective boilers (1). ), The water supply control valve (13) and the constant flow control valve
(40) is connected in series. Also in this case, when the water supply control valve (13) that is individually controlled to be opened and closed by each boiler (1) is opened as in the case of the above-described embodiment, the water supply flowing through this water supply control valve (13) becomes the constant flow control valve (40). ), The fluid is supplied to each boiler (1) because it is controlled to a constant flow rate.
Can be performed stably.

[0023]

EFFECTS OF THE INVENTION Since the present invention has the above-described structure, the pressure on the discharge side of the fluid supply device is adjusted to a constant value regardless of the number of operating boilers, and the control valves on each boiler side are individually controlled. By controlling the opening and closing, a predetermined fluid can be supplied to each boiler according to the operating status of each boiler, and the cost of the fluid supply device in the multi-can installation system of the boiler can be reduced.
It is possible to realize simplification of the structure. That is, it is possible to supply fluid to a plurality of boilers with only a small number of fluid supply devices, reduce the number of fluid supply devices, simplify fluid supply piping and wiring, and A low cost system can be provided. Further, since the operation status of the boiler is detected and the discharge side pressure is controlled to be constant, the flow rate due to the opening time of the control valve is constant, and
Since the supply amount can be appropriately maintained, each control of the water level control and the combustion control can be normally performed.

Further, according to the present invention, even when performing overhead piping, the number of fluid supply devices can be minimized, which is easy and the flexibility of piping is high. Further, since it is not necessary to separately provide the fluid supply device on the boiler side, it is not necessary to consider the pressure loss of the suction side pipe, and the pipe can be made thin, so that the pipe can be manufactured at low cost. As described above, according to the present invention, it is possible to configure a boiler multi-can installation system excellent in initial cost and running cost.

[Brief description of drawings]

FIG. 1 is a drawing for explaining a piping system of a first embodiment of the present invention.

FIG. 2 is a drawing for explaining a piping system according to a second embodiment of the present invention.

FIG. 3 is a drawing for explaining a piping system of a third embodiment of the present invention.

[Explanation of symbols]

 (1) Boiler (10) Water supply line (main fluid supply route) (12) Water supply pump (fluid supply device) (13) Water supply control valve (control valve) (14) Pressure regulator (20) Fuel supply line (fluid supply) (Main path) (21) Air supply line (main fluid supply path) (23) Fuel pump (fluid supply device) (25) Fuel control valve (control valve) (26) Blower (fluid supply device) (28) Air control valve (Control valve) (29) Fuel pressure regulator (pressure regulator) (30) Air pressure regulator (pressure regulator) (40) Constant flow control valve

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shigeaki Nishioka 7 Horie-cho, Matsuyama-shi, Ehime Miura Industry Co., Ltd.

Claims (2)

[Claims] 1. A multi-can installation system for a boiler, wherein a plurality of boilers (1) are installed and the number of operating boilers (1) is controlled according to the load amount. Each boiler (1) is equipped with a control valve (13).
Through the fluid supply main path (10), the fluid supply main path (10) is connected to the fluid supply device (12), the fluid supply main path on the discharge side of the fluid supply device (12) ( Ten)
Is equipped with a pressure adjusting device (14) for maintaining the fluid pressure of the boiler at a constant level, and by controlling the opening and closing of the control valve (13) corresponding to the operating boiler (1), the fluid flow to each boiler (1) is controlled. A fluid supply device for a multi-can installation system of a boiler, characterized by controlling supply. 2. In a boiler multi-can installation system in which a plurality of boilers (1) are installed and the number of operating boilers (1) is controlled according to the load amount, each boiler (1) has its own control valve (13).
Also, connected to the fluid supply main path (10) through the constant flow control valve (40), the fluid supply main path (10) is connected to the fluid supply device (12) which is activated when the boiler (1) is operated, Boiler in operation
A fluid supply device in a multi-can installation system for a boiler, wherein the supply of fluid to each boiler (1) is controlled by controlling the opening and closing of the control valve (13) corresponding to (1).