JP2630878B2 - Condensate recovery equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condensate recovery apparatus for recovering condensate generated in equipment using steam to a boiler or the like.
Condensate generated in equipment using steam is generally discharged via a steam trap. The discharged condensate is generally a condensate of high-pressure steam, and still has high-temperature thermal energy, and condensate is collected to measure the effective use of this thermal energy. In order to collect condensed water and pump it to a desired location such as a boiler, the outlet side of a steam trap is connected to a condensate pump device. In this case, the condensed water to be recovered has a higher recovery efficiency as the amount of retained heat is larger, that is, as the saturation pressure of the condensed water is higher. However, if the saturation pressure of the condensate is increased to increase the recovery efficiency, the differential pressure before and after the steam trap is not secured, the discharge capacity of the trap decreases, and the condensate generated by the steam-using equipment is not discharged. The fuel traps stay on the inlet side of the steam trap and eventually in the equipment using steam, and the thermal efficiency of the equipment is reduced.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional condensate recovery apparatus. In FIG. 2, the steam supply pipe 1
The steam trap 3 is connected to the secondary side of the steam-using equipment 2 communicating with the steam pump 3, the ejector 4 of the combined pump 6 including the ejector 4 and the electric pump 5 is connected to the steam trap 3, and the steam trap 3 and the ejector 4 are connected. Pressure release passage 7 between
, A pressure control valve 8 is disposed, a circulation passage of the combination pump 6 is branched and a condensate recovery passage 9 is provided, and a pressure control valve 10 is provided.
The pressure regulating valves 8 and 10 are set to a desired pressure, the secondary side of the steam trap 3 is maintained at a predetermined low pressure, and the required amount of circulating water of the combination pump 6 is secured. Thus, stagnation of the condensed water is prevented, and the condensed water is surely collected.

[0003]

In the above conventional apparatus, when the condensate recovery device is installed and the operation is started for the first time, the set pressure of each pressure control valve is adjusted according to the transmission state of the equipment using steam. It has to be adjusted, and this adjustment requires experience, and there is a problem that it is necessary to be present until the entire operation process of the steam-using device is completed, which requires much time. In other words, the set pressure can maintain a pressure difference enough for the steam trap to discharge condensate,
This is because the pressure must be set as high as possible, and the steam pressure may change in the operation process of the steam-using device.

[0004] Accordingly, it is an object of the present invention to provide a condensate recovery apparatus that can easily and quickly set an optimum pressure of a pressure control valve.

[0005]

The constitution of the condensate recovery apparatus of the present invention is as follows. Condensate discharge means such as a steam trap is connected on the secondary side of the steam-using equipment, and a combined pump combining an ejector and an electric pump is connected on the secondary side of the condensate discharge means and combined with the condensate discharge means A pressure relief passage is provided between the pump and the pressure relief valve disposed in the pressure relief passage, and a condensate recovery passage for pumping a portion of the circulating water of the combination pump to a condensate recovery destination such as a boiler is provided. A pressure control valve is disposed in the condensate recovery passage, and pressure detection means for detecting pressures on the inlet side of the condensate discharge means, between the condensate discharge means and the ejector, and on the inlet side of the electric pump are attached. A controller comprising a calculation unit for calculating a set pressure of the pressure control valve based on a detection signal from the pressure detection means and a transmission unit for issuing a calculation signal; and a signal from the controller to adjust the pressure control valve to a desired amount. Drive unit that drives only Those attached to the pressure regulating valve.

[0006]

The pressure on the inlet side and the outlet side of the condensate discharge means and the pressure on the inlet side of the electric pump are detected by the pressure detection means, and the pressure on the outlet side of the condensate discharge means is reduced by the arithmetic unit to the pressure on the inlet side. On the other hand, the pressure at the inlet side of the electric pump is calculated as a low pressure that does not cause the condensate to stay. A value is calculated that circulates and ensures a pressure at which condensate can be sucked by the ejector section. If the pressure on the inlet side of the electric pump is lower than the pressure on the inlet side of the ejector, cavitation occurs in the electric pump, and the circulation amount of the combination pump cannot be secured. This makes the condensate suction impossible. The set pressure of the pressure control valve calculated by the calculation unit is sent from the transmission unit to the drive unit, and sets the pressure control valve to a desired set pressure. The pressure difference between the inlet side and the outlet side of the condensate discharge means may be, for example, at least 0.1 kg to 0.3 kg when a free float type steam trap is used, The pressure difference between the inlet and the ejector inlet should be at least 0.3
It may be about 0.5 km to 0.5 km.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described in detail with reference to FIG. Steam trap 12 attached to the secondary side of equipment 11 using steam
, The combination pump 13 and the automatic pressure control valves 14, 15,
The controller 16 constitutes a condensate recovery device.

A pressure sensor 17 as a pressure detecting means is attached to the inlet side of the steam trap 12 and connected to the controller 16. A header 19 is provided between the steam trap 12 and the ejector 18 of the combination pump 13 and a pressure sensor 20 is attached. The automatic pressure control valve 14 is disposed so as to communicate with the pressure release passage 21 from the header 19. The pressure sensor 23 is attached to the inlet side of the electric pump 22 of the combination pump 13. The pressure sensors 20 and 23 are also connected to the controller 16. The circulation path of the combination pump 13 is branched to provide a condensate recovery passage 2b and the automatic pressure control valve 15
Place. The drive units 26 of the automatic pressure control valves 14 and 15
27 and the controller 16 are connected. Although not shown, the controller 16 includes a calculation unit, a transmission unit, a storage unit, a display unit, and the like.

A steam pipe 31 is connected to the steam-using equipment 11 via an automatic pressure control valve 30 for supplied steam. The drive unit 32 of the automatic pressure control valve 30 is also connected to the controller 16.

Next, the operation will be described. The steam supplied from the steam pipe 31 is condensed in the steam-using device 11 and passes through the steam trap 12 to the ejector 18 of the combination pump 13.
Is sucked. In this case, if the pressure difference before and after the steam trap 12 is small, the amount of condensate discharged from the trap 12 decreases, and condensate remains in the steam-using device 11. Therefore, if the difference between the pressure values detected by the pressure sensors 17 and 20 falls within a predetermined value, for example, 0.3 km or less, the automatic pressure control valve 14 is opened by a signal from the controller 16 so as not to cause such a state. By doing so, the pressure on the outlet side of the trap 12 is released, and a predetermined pressure difference can be maintained.

Similarly, the pressure on the inlet side of the ejector 18 and the pressure on the inlet side of the electric pump 22 are measured by the pressure sensors 20 and 2.
3 and the pressure difference between the two is within a predetermined value, for example, 0.5
By controlling the opening and closing of the automatic pressure control valve 15 so that the pressure becomes equal to or more than a kilo, the required amount of circulating water in the combination pump 13 is secured, and the condensed water is reliably sucked by the ejector 18.

When the supply steam pressure to the steam-using equipment 11 is changed, the controller 16 controls the automatic pressure control valve 3
It can be changed by sending a pressure signal to the zero drive unit 32. In this case, by detecting the new pressure by the pressure sensor 17, the automatic pressure control valves 14, 15 are detected.
Is automatically calculated and set.

In this embodiment, the steam trap 1
Although the pressure sensor 17 on the inlet side of No. 2 is mounted on the outlet side of the steam-using device 11, it can be mounted on the inlet side.

[0014]

The present invention has the following effects. Based on the pressure on the inlet side of the condensate discharge means, the pressure on the outlet side of the condensate discharge means and the pressure on the inlet side of the electric pump are automatically detected and calculated, and the drive unit is driven, The optimal pressure of the pressure relief passage and the condensate recovery passage is set,
There is no need for adjustment at the start of operation, and there is no need to be present throughout the entire operation process of the steam-using device.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a condensate recovery device of the present invention.

FIG. 2 is a configuration diagram of a conventional condensate recovery device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Steam use apparatus 12 Steam trap 13 Combination pump 14, 15 Automatic pressure control valve 16 Controller 17, 20, 23 Pressure sensor 18 Ejector 21 Relief passage 22 Electric pump 25 Condensate recovery passage

Claims (1)

(57) [Claims] 1. A condensate discharge means such as a steam trap is connected to a secondary side of a steam-using device, and a combined pump combining an ejector and an electric pump is connected to a secondary side of the condensate discharge means. A condensate discharge passage is provided between the water discharge means and the combination pump, a pressure control valve is disposed in the discharge passage, and a part of the circulating water of the combination pump is pressure-fed to a condensate collection destination such as a boiler. In the case where a passage is provided and a pressure regulating valve is disposed in the condensate recovery passage, the pressure on the inlet side of the condensate discharge means, between the condensate discharge means and the ejector, and on the inlet side of the electric pump are respectively detected. A pressure detection means is attached, a controller comprising a calculation unit for calculating a set pressure of the pressure control valve based on a detection signal from the pressure detection means and a transmission unit for issuing a calculation signal is arranged, and the pressure is controlled by a signal from the controller. Drive the control valve by the desired amount. A condensate recovery device with a moving drive unit attached to a pressure control valve.