JPS62141407A - Controller for injection quantity of cooling water for steamdesuperheater - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a cooling water injection amount control device for a steam desuperheater.
In particular, the present invention relates to a cooling water injection amount control device for a steam desuperheater that injects cooling water into superheated steam to lower the temperature of the superheated steam to a predetermined temperature.

[Prior art 1] When heating a substance using steam, it is desirable to use saturated steam. Figure 3. Conventional steam reducer 4,51 cooling 7J for converting Li superheated steam to saturated steam] Water injection! The control system of the H control system is shown in diagram J, and FIG. 4 is a state diagram of steam.

In FIG. 3, superheated steam is supplied to a superheated steam pipe 1, and the steam pressure inside the superheated steam pipe 1 is detected by a pressure detector 2. The detection output of the pressure detector 2 is sent to the steam pressure regulator 3, and the steam pressure regulator 3 is set in advance based on the steam pressure detected by the pressure detector 2. Pressure regulating valve 4 is controlled 11 until the steam pressure is reached. Thereby, the pressure inside the superheated steam pipe 1 is kept constant. The superheated steam pipe 1 is provided with a cooling water injection device 7 .

A hot stone detector 5 is provided on the output 1 side of the superheated steam pipe 1 to detect the temperature of the superheated steam.

The temperature detected by this temperature detector 5 is determined by the steam temperature controller 6.
given to. The steam temperature regulator 6 controls the flow rate of the cooling water supplied to the cooling water injection device u7 so that the temperature detected by the temperature detector 5 reaches a preset temperature. This cooled iJI into superheated steam by J)J water injection device 7
Water is injected, and superheated steam 19 whose temperature has been reduced is supplied to the outlet 21 side of the superheated steam pipe 1. In other words, superheated steam F! i
! On the exit side of 'i'X1, the steam temperature is constant J
, adjusted to sea urchins.

[Problems to be Solved by the Invention] Incidentally, as shown in FIG. 4, even if the temperature of saturated steam is constant, the degree of dryness of saturated steam differs by the amount of enthalpy. For this reason, as mentioned above, the hot stone of superheated steam is detected and the cooling water q1 is injected h1 to maintain a constant temperature.
Control 6Il'? In this case, if the flow rate of the steam used is not stable, it becomes difficult to achieve a superheat degree of O after temperature reduction. =Generally, when superheated steam is used in the Iζ system J3, the flow rate of the steam changes from moment to moment, so in order to make the degree of superheating after temperature reduction O, superheated steam with a slight degree of superheating and I adjusted it accordingly.

However, this adjustment was difficult and unsuitable for use as steam for heating objects.

Therefore, the main object of the present invention is to dry the steam after cooling to a temperature equal to 4T of saturated steam. 1. Sea urchin, superheated steam.

To provide a cold 7JI water injection amount control device for a steam subtractor that processes cooling water corresponding to the superheated steam flow rate from each of the cooling water into a suitable steam for heating. That's true.

[Means for Solving the Problems] A cooling water injection amount control device for a steam attenuator according to the present invention includes a temperature detection means for detecting the temperature 4 of superheated steam and a flow rate of the superheated steam. 1I(
It consists of an I-temperature control means and a cooling water injection means for injecting cooling water into the superheated steam based on the calculated injection amount.

[Operation] Does this invention reduce steam? The cooling water injection amount control device of the flA unit calculates the injection amount of cooling water to make the preset dry saturated steam based on the temperature of the superheated steam and the steam flow rate, and based on the calculation result of (a) Since the injection amount of cold water can be controlled, superheated steam can be processed into dry saturated steam suitable as heating steam even in systems where the steam flow rate fluctuates greatly. .

[Embodiment of the Invention] FIG. 1 is a schematic diagram showing a control system of an embodiment of the present invention, and FIG. 2 is a schematic block diagram of the cooling water flow rate setting device shown in FIG. 1. be.

First, an embodiment of the present invention will be described with reference to FIG. 1 J3 and FIG. 2. In FIG. 1, the same superheated air piping 1, pressure detector 2, steam pressure regulator 3, and pressure regulating valve 1 as shown in FIG. 3 are used. Furthermore, the superheated steam pipe 1 includes a steam flow rate detector 8 that detects the flow rate of superheated steam in the superheated steam pipe 1,
A temperature detector 5 is provided to detect the humidity of the superheated steam.

The lζ flow rate detected by the steam flow rate detector 8 and the temperature detected by the temperature detector 5 are provided to a cooling water flow rate setting device 9. Based on the input flow rate a3 and temperature, preset information, and an arbitrary function, the cooling water flow rate setting device 9
The flow rate of cooling water corresponding to the steam flow rate is calculated, and the flow rate of the cold 7J1 water flow controller 11 is adjusted. Cooling water flow h') control 1
1i'i device 11 is given a detection output from a water flow rate detector 10 that detects the flow rate of cold moon 1 water, and the flow rate detected by this water flow rate detector 10 is applied to the cooling water flow I'll setting device. 9 [・Cold water jet, 0 water jet θ=
I Control the device 7. Thereby, cooling water corresponding to the steam flow rate is injected from the cooling water injection device 7, processed into dry saturated steam, and output.

Next, the cooling water flow ffi RQ regulator 9 will be explained in detail. As shown in FIG. 2, the cooling water flow rate setting device 9 includes an input buffer 791, a constant setting device 92, and a multiplexer 93.
, a Δ/D converter 9/l, a control section 95, an output circuit 96, and a display 97. The input buffer 91 receives the steam flow 111 detected by the steam flow rate detector 8 shown in FIG. 1, and the steam humidity detected by the humidity IQ detector 5. Note that this input buffer 91 has 11
In addition to inputting the steam pressure detected by the force detector 2, the temperature of the cooling water may be detected and the temperature information may be provided. The constant setter 92 is used to set the desired dry saturated steam concentration and the upper limit value d3 and lower limit value of the amount of cooling water. Each piece of information input to the input buffer 91 and the set value set by the constant setter 92 are given to a multiplexer 93. Multiplayer Cree-93
is given from the input buffer 91 and sequentially selects the setting values set by the Iζ information and the constant setter 92 and supplies them to the Δ/D converter 94.

The Δ/D converter 9/l converts the information into a digital signal and provides it to the control section 95.

The control unit 95 calculates the corrected steam flow rate J3 and the amount of cooling water based on the input information. That is, the steam pressure is P
The corrected steam flow rate Fs is determined by the following equation, where the steam temperature is expressed as Α, the differential pressure is expressed as Δp, the water injection temperature is expressed as Tv, the corrected steam flow rate is expressed as FS, and the amount of cooling water is expressed as Fw.

However, K1- and 4 are constants and cooling water ff), and I-W is determined by the following formula.

However, 13. Pl is a constant. Based on the corrected steam flow rate J: and the amount of cooling water calculated by the control unit 95 as described above, the output circuit 96 sets the amount of cooling water in the cold water flow ffi adjuster 11).

The cooling water flow flI) regulator 11 controls the cooling water injection device 7 based on the cooling water flow rate set by the cooling water flow rate setting device 9. Due to this, dry saturated steam is released from the output side of superheated steam pipe 1! 'l will be.

[Effects of the Invention] As described above, according to the present invention, the injection amount of cooling water required to make superheated steam dry and saturated steam is calculated based on at least the flow rate and temperature of superheated steam, and Since the flow rate of the cooling water is adjusted using the set value of the cooling water flow rate controller, L1 is used in processes where the steam flow rate fluctuates greatly.
5, superheated steam can be processed into dry saturated steam suitable for use as heating steam. Therefore, it is possible to solve problems such as non-uniformity of humidity on the heating surface of the heating device and generation of large thermal stress when superheated steam is used.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a control system of an embodiment of the present invention. FIG. 2 is a concrete block diagram of the cooling water flow rate setting device shown in FIG. 1. FIG. 3 is a schematic diagram of a control system of a conventional steam desuperheater cooling water injection amount control device. FIG. 4 is a state diagram of steam. In the figure, 1 is a superheated steam pipe, 2 is a pressure detector, 3 is a steam pressure regulator, 4 is a pressure regulating valve, 5 is a temperature detector, and 7
8 is a cooling water injection device, 8 is a steam flow rate detector, 9 is a cooling water flow rate setting device, 10 is a water flow rate detector, and 11 is a cooling water flow rate regulator.

Claims (3)

[Claims] (1) A cooling water injection amount control device for a steam desuperheater for controlling the injection amount of cooling water in order to turn superheated steam into dry saturated steam, the device comprising: a temperature detecting device for detecting the temperature of the superheated steam; a detection means, a steam flow rate detection means for detecting the flow rate of the superheated steam, a preset dry saturated steam based on the temperature detected by the temperature detection means and the flow rate detected by the steam flow rate detection means. steam, comprising: an arithmetic control means for calculating the injection amount of the cooling water in order to achieve the desired temperature; and a cooling water injection means for injecting the cooling water into the superheated steam based on the injection amount calculated by the arithmetic and control means. Cooling water injection amount control device for desuperheater. (2) Furthermore, it includes a steam pressure detection means for detecting the pressure of the superheated steam, and the arithmetic and control means is configured to:
A cooling water injection amount control device for a steam desuperheater according to claim 1, wherein the cooling water injection amount control device calculates the cooling water injection interval. (3) The cooling water injection means further includes a flow rate detection means for detecting the flow rate of the cooling water, and the cooling water injection means is configured to control the superheating so that the flow rate detected by the flow rate detection means becomes the calculated injection amount. A cooling water injection amount control device for a steam desuperheater according to claim 1, which adjusts the flow rate of cooling water injected into the steam.