JP2010038458A - Steam quality monitoring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steam quality monitoring apparatus, preventing an obstacle to steam quality monitoring work due to sludge brought together with condensed drain water in a steam pipe in starting the operation of a boiler. <P>SOLUTION: In the steam quality monitoring apparatus, impurity quantity in steam generated by a boiler is continuously monitored using a heat exchanger 2 which makes vapor from the boiler into condensed water G using a refrigerant C and a measuring means 3 for measuring the water quality of the condensed water G from the heat exchanger 2. A steam trap 42 for discharging the condensed drain water generated by condensation of steam S in a steam pipe 40 is provided at the end of a steam sampling pipe 40 from a boiler for supplying steam S to the heat exchanger 2, and the steam sampling pipe 40 and the heat exchanger 2 are connected to a branch pipe 41 from the steam sampling pipe 40, to which the condensed drain water in the steam sampling pipe 40 is inhibited from flowing. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention uses a heat exchanger that converts steam from a boiler into condensed water using a refrigerant, and a measuring means that measures the quality of condensed water from the heat exchanger, The present invention relates to a vapor quality monitoring device that continuously monitors the amount of impurities.

  With the generalization of product heating and sterilization operations by direct blowing of steam into products and the spread of small once-through boilers, the amount of impurities in steam, that is, the quality (quality) of steam, becomes a problem. Small once-through boilers (defined as special circulation boilers in JIS B8223) are relatively inexpensive and easy to use, but the capability of the steam separator is low and the generated steam tends to contain impurities. is there. For this reason, in such a case, a vapor quality monitoring device that continuously samples the vapor and constantly monitors the amount of impurities in the vapor and prevents the vapor from being used when the vapor quality deteriorates ( Patent Document 1) has been proposed.

  As shown in FIG. 2, the steam quality monitoring apparatus 100 uses the cooling water C to cool the steam S to make the condensed water G, and the condensation from the heat exchanger 101. And a measuring device 102 that measures the amount of impurities in the water G. In the steam quality monitoring device 100, in order to accurately measure the quality of the steam S, it is necessary to make the flow rate of the condensed water G supplied to the measuring device 102 constant, and the temperature of the condensed water G is set to an upper limit value. It is necessary to make the following constant values.

  For this reason, in this vapor quality monitoring apparatus 100, the flowmeter 103 and the flow regulating valve 104 are provided in the condensed water line at the outlet of the heat exchanger 101, and the control unit 110 is arranged so that the flow rate of the condensed water G is constant. Thus, the opening degree of the flow control valve 104 is automatically controlled. In the vapor quality monitoring apparatus 100, a temperature adjustment valve 105 is provided in the supply line of the cooling water C to the heat exchanger 100, and a thermometer 106 is provided in the condensed water line at the outlet of the heat exchanger 101. The opening degree of the temperature regulating valve 105 is automatically controlled via the control unit 110 so that the temperature of the condensed water G at the outlet becomes constant.

  On the other hand, in the steam quality monitoring device 100, when the operation of the boiler is stopped and the steam pressure in the steam pipe 107 for supplying steam to the heat exchanger 101 decreases, the solenoid valve 108 is closed and the steam pipe 107 is shut off. At the same time, when the boiler resumes operation and the steam pressure in the steam pipe 107 rises, the electromagnetic valve 108 is opened, and the steam S on the boiler side is taken from the steam pipe 107.

JP 2007-93128 A

  By the way, in the steam quality monitoring device 100, when the operation of the boiler is stopped and the solenoid valve 108 is closed, condensed drainage water that is condensed by cooling the steam is stored in the steam pipe 107 on the upstream side of the solenoid valve 108. When the electromagnetic valve 108 is opened by restarting the boiler operation, this condensed wastewater flows into the heat exchanger 101 side at once. As a result, the sludge such as corrosion products generated in the steam pipe 107 also moves to the heat exchanger 101 side together with the condensed waste water, and this is a steam filter provided in the steam pipe 107 immediately before the electromagnetic valve 108. There was a problem of blocking (not shown).

  For this reason, the conventional steam quality monitoring apparatus 100 has a problem that the number of times of cleaning or replacement of the steam filter is increased and the number of flushing of the steam pipe 107 is increased, thereby hindering the monitoring work of the steam quality.

  In addition, the pressure of the steam generated in the small once-through boiler, for example, oscillates greatly in a width of about 0.2 MPa, such as 0.6 to 0.8 MPa, and the fluctuation of the steam pressure causes the above The flow rate of the steam supplied to the steam quality monitoring apparatus 100 varies. However, in the steam quality monitoring device 100, the flow rate adjustment valve 104 on the condensed water G side may not be able to sufficiently control the fluctuation of the flow rate of the steam, and as a result, the flow rate of the condensed water G flowing on the measuring instrument 102 side. Has become unstable and difficult to be constant.

  Furthermore, in the said vapor quality monitoring apparatus 100, since the expensive flow regulating valve 104 and the control part 110 which are automatically controlled are used for the flow control of the condensed water G, it says that an apparatus will become high-cost. There is a problem that there are problems and there are not a few operation troubles of the flow rate adjusting valve 104. The same can be said for the temperature control valve 105 that automatically controls the temperature of the condensed water G.

  In view of the above, the present invention provides a steam quality monitoring device that does not hinder the steam quality monitoring work due to sludge brought in along with the condensed drainage in the steam pipe at the start of boiler operation. The first purpose is to provide it.

  Further, in addition to the first object, the present invention, in addition to the monitoring of the steam quality, even if the steam pressure fluctuates on the boiler side, the flow rate of the condensed water at the outlet of the heat exchanger can be reduced without cost. A second object of the present invention is to provide a vapor quality monitoring device that can be reliably kept constant with few operation troubles.

  Furthermore, in addition to the second object, the present invention keeps the temperature of the condensed water at the outlet of the heat exchanger at a constant value smaller than the upper limit value without incurring costs and causing operational troubles. It is a third object to provide a vapor quality monitoring device capable of performing the above.

  Invention of Claim 1 of this invention uses the heat exchanger which makes the vapor | steam from a boiler into condensed water using a refrigerant | coolant, and the measurement means which measures the water quality of the said condensed water from this heat exchanger, In the steam quality monitoring device for continuously monitoring the amount of impurities in the steam generated in the boiler, the steam in the steam pipe is connected to the end of the steam pipe from the boiler that supplies the steam to the heat exchanger. A branch pipe from the steam pipe is provided with a steam trap that discharges the condensed waste water generated by the condensation of the steam pipe, and the steam pipe and the heat exchanger are prevented from flowing in the condensed waste water in the steam pipe. It is characterized by having connected by.

  In this invention, the operation of the boiler is started, and even if the condensed waste water stored in the steam pipe from this boiler is pushed by the steam toward the heat exchanger side, this condensed waste water is not supplied to the heat exchanger side. Does not move and is discharged to the outside from the steam trap at the end of the steam pipe. Therefore, the sludge consisting of corrosion products in the steam pipe also moves to the steam trap side together with the condensed waste water, and is discharged to the outside through this steam trap. Note that steam from the boiler in the steam pipe passes through the branch pipe and is sent to the heat exchanger side.

  According to a second aspect of the present invention, in the case of the first aspect of the present invention, the steam pressure at the inlet of the heat exchanger is applied to the steam pipe or the branch pipe from the boiler. A pressure reducing valve for reducing the pressure to a constant pressure not affected by fluctuations is provided, and the condensate flow rate measuring means is manually set in the condensed water line between the heat exchanger and the measuring means, and the valve opening is manually set. And a manual flow rate adjusting valve that is fixed.

  In this invention, the steam pressure at the inlet of the heat exchanger is reduced to a constant pressure that is not affected by pressure fluctuations caused by the boiler by the pressure reducing valve. For this reason, the pressure of the condensed water at the outlet of the heat exchanger becomes constant, and the flow rate of the condensed water at the outlet of the heat exchanger is determined by the opening degree of the flow rate adjusting valve provided in the condensed water line. Therefore, while looking at the value of the flow rate measuring means provided in this condensate line and manually setting the opening of the flow rate adjustment valve so that it becomes a predetermined value, for example, remove the opening / closing handle of the flow rate adjustment valve Thus, by fixing the opening of the flow rate adjusting valve, the flow rate of the condensed water at the outlet of the heat exchanger can be set to a predetermined constant value.

  According to a third aspect of the present invention, in the case of the second aspect, the refrigerant temperature measuring means is provided in the refrigerant discharge line for the heat exchanger, and the refrigerant for the heat exchanger is provided. The refrigerant flow rate measuring means is provided in the supply line or the discharge line, and the heat is supplied to the refrigerant supply line by an amount such that the refrigerant temperature at the outlet of the heat exchanger is smaller than a predetermined set value. A first manual flow rate adjusting valve, in which the valve opening is manually set and fixed, and an electromagnetic valve that is opened when the boiler is started are arranged in series so that the refrigerant flows through the exchanger. A flow rate adjustment unit is provided, and the refrigerant supply line is parallel to the first flow rate adjustment unit, the refrigerant temperature at the outlet of the heat exchanger reaches the set value, and the temperature of the condensed water is the upper limit. In the event of an abnormality approaching, the valve opening is manually set and fixed so that the refrigerant flows through the heat exchanger by a predetermined amount in addition to the first flow rate adjustment unit. A second flow rate adjustment unit is provided in which a valve and an electromagnetic valve opened in the event of an abnormality are arranged in series.

  In the present invention, when the temperature of the refrigerant at the outlet of the heat exchanger exceeds a predetermined set value, the temperature of the condensed water at the outlet of the heat exchanger approaches the upper limit value. And the refrigerant is allowed to flow through the heat exchanger at a constant flow rate such that the temperature of the refrigerant at the outlet of the heat exchanger becomes smaller than a predetermined set value by using the flow rate regulating valve of the first flow rate regulating unit. . In this case, since the flow rate of the condensed water at the outlet of the heat exchanger is constant, the amount of heat that the steam brings into the heat exchanger varies slightly due to fluctuations in the steam pressure on the boiler side, but is considered to be substantially constant. For this reason, in this invention, the temperature of condensed water can be fixed by using a 1st flow volume adjustment unit.

  Further, in the present invention, when the refrigerant temperature at the heat exchanger outlet exceeds the set value for some reason and the temperature of the condensed water at the outlet of the heat exchanger approaches the upper limit value, it is added to the first flow rate adjustment unit, The electromagnetic valve of the second flow rate adjustment unit is also opened, and a sufficient amount of refrigerant is supplied to the heat exchanger using the flow rate adjustment valve of the first flow rate adjustment unit. Do not exceed the upper limit.

  According to the invention described in claim 1 of the present invention, sludge composed of corrosion products generated in the steam pipe from the boiler can be discharged to the outside through the steam trap together with the condensed waste water. Therefore, it is possible to monitor the vapor quality continuously and stably without hindering the vapor quality monitoring work.

  According to the second aspect of the present invention, the flow rate of the condensed water at the outlet of the heat exchanger can be made constant by providing an inexpensive pressure reducing valve and an inexpensive manual flow rate adjusting valve. For this reason, according to the present invention, it is not necessary to provide an expensive flow rate adjustment valve that automatically keeps the flow rate of the condensed water constant, the cost of the equipment can be reduced, and the trouble of the equipment can be reduced. it can. In these inventions, since the steam pressure at the heat exchanger inlet is constant, the flow rate of the steam supplied to the heat exchanger is not affected by the boiler, and the flow rate of the condensed water is also ensured to be constant. Can do.

  According to the invention described in claim 3 of the present invention, by providing a plurality of sets of flow rate adjusting units each including an inexpensive manual flow rate adjusting valve and an inexpensive electromagnetic valve, the condensate temperature at the outlet of the heat exchanger can be set at an abnormal time. In the case of, it is possible to make it constant without exceeding the upper limit value. For this reason, according to the present invention, it is not necessary to provide an expensive flow rate adjusting valve that automatically keeps the temperature of the condensed water constant, the cost of the equipment can be reduced, and the operation trouble of the equipment can be reduced. it can.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a vapor quality monitoring apparatus according to an embodiment of the present invention.

  The steam quality monitoring device 1 cools the steam from a small once-through boiler (hereinafter referred to as a boiler) to condensate, then continuously measures the quality of the condensate, and is generated in the boiler from the quality of the condensate. It is intended to continuously check (monitor) the quality of the generated steam.

  As shown in FIG. 1, the steam quality monitoring device 1 includes a heat exchanger 2, a measuring device 3, a steam supply line 4, a condensed water line 5, a cooling water supply line 6, and a cooling water discharge line. 7, a control unit 8, and an operation state display unit 9.

  The heat exchanger 2 is for cooling the steam S supplied via the steam supply line 4 with cooling water C as a refrigerant, and converting the steam S into condensed water G having a predetermined flow rate at a predetermined temperature. is there. In the heat exchanger 2, for example, the steam S flows from the upper part to the lower part, and the cooling water C flows from the lower part to the upper part so as to face each other.

  The measuring device 3 is a measuring means for measuring the amount of impurities in the condensed water G, and was measured by a dissolved oxygen meter 30, an electric conductivity meter 31, a pH meter 32, and these meters 30, 31, 32. It has a display recording unit 33 for displaying / recording the measured value and a discharge unit 34 for discharging the condensed water G after the measurement. The dissolved oxygen concentration meter 30 measures the dissolved oxygen concentration in the condensed water G, whereby the amount of oxygen contained in the steam S is determined. The electric conductivity meter 31 measures the electric conductivity of the condensed water G, whereby the amount of inorganic impurities in the steam S is determined. The pH meter measures the pH value of the condensed water G, and thereby the degree of pH-influencing components in the steam S is determined. The condensed water G that has been measured is discharged from the discharge unit 34 to the outside. The measured dissolved oxygen concentration value, electrical conductivity value, and pH value are displayed on the display recording unit 33 and recorded.

  Here, when the flow rate and temperature of the condensed water G supplied to the measuring device 3 fluctuate during the measurement, the relationship between the measurement result by the measuring device 3 and the amount of impurities in the steam S is constant. Therefore, the reproducibility of the measurement result is not good. In addition, the temperature of the condensed water G supplied to the measuring device 3 is provided with an upper limit value (for example, 40 ° C.) from the viewpoint of protecting the measuring device 3.

  The steam supply line 4 is for supplying steam S from the boiler to the heat exchanger 2. The steam supply line 4 branches from the steam sampling pipe 40 as a steam pipe connected to the boiler side pipe and the steam sampling pipe 40, and supplies the steam S in the steam sampling pipe 40 to the heat exchanger 2. It has a branch pipe 41, a steam trap 42 provided at the lower end of the downward pipe part 40 a at the end of the steam sampling pipe 40, and a drain pipe 43 connected to the steam trap 42. The steam supply line 4 includes a steam filter 44, a pressure reducing valve 45, and an electromagnetic valve 46 in the branch pipe 41.

  The branch pipe 41 is horizontally branched from the downward pipe section 40 at the end of the steam sampling pipe 40 so as not to bring condensed drainage generated by the condensation of the steam S in the steam sampling pipe 40 to the heat exchanger 2 side. . In addition, as shown by a two-point diagonal line in FIG. 1, the branch pipe 41 rises upward at the joint with the steam sampling pipe 40 so that the condensed waste water in the steam sampling pipe 40 does not flow into the heat exchanger 2 side. It may be the one. The pressure reducing valve 45 reduces the upstream primary steam pressure to the downstream secondary steam pressure, and keeps the secondary steam pressure constant.

  The condensed water line 5 is for supplying the measuring device 3 with the condensed water G produced by the heat exchanger 2. The condensed water line 5 includes a condensed water pipe 50 from the heat exchanger 2 to the measuring device 3, and a flow rate adjustment valve 51, a condensed water flow meter 52, and a condensed water thermometer provided in the condensed water pipe 50. 53 and a branch line 54 between the condensate flow meter 52 and the condensate thermometer 53. The flow rate adjusting valve 51 can manually adjust the valve opening, and, for example, a manually adjustable flow rate adjustable valve that can be fixed manually by locking or removing the opening / closing handle so as not to move, For example, a needle valve.

  The cooling water supply line 6 is for supplying the cooling water C to the heat exchanger 2. The cooling water supply line 6 includes a cooling water inlet pipe 60 that connects the heat exchanger 2 and a cooling water source, a cooling water flow meter 61 provided in the cooling water inlet pipe 60, and a cooling water flow meter 61. First and second flow rate adjusting units 62 and 63 are provided in parallel with each other in the cooling water inlet pipe 60 on the downstream side.

  The first flow rate adjusting unit 62 supplies the cooling water to the heat exchanger 2 at a flow rate such that the temperature of the cooling water C in the cooling water outlet line 7 is lower than a predetermined set value (for example, 70 ° C.) during normal monitoring. C is supplied and has a function of maintaining the temperature of the condensed water G at the outlet of the heat exchanger 2 at a predetermined constant value. The first flow rate adjusting unit 62 includes an electromagnetic valve 62a, a flow rate adjusting valve 62b disposed on the downstream side of the electromagnetic valve 62a, and a pipe 62c that connects them. The flow rate adjustment valve 61c is a valve similar to the flow rate adjustment valve 51, and is a manually adjustable flow rate adjustable valve that can manually adjust the valve opening and can manually fix the valve opening, for example, a needle valve.

  The second flow rate adjustment unit 63 is a first flow rate adjustment unit when the cooling water temperature of the cooling water outlet line 7 reaches a set value (70 ° C.) and the temperature of the condensed water G approaches the upper limit value (40 ° C.). In addition to 62, the cooling water C is supplied to the heat exchanger 2 by a predetermined amount, the cooling water temperature of the cooling water outlet line 7 is lowered from the set value (70 ° C.), and the condensed water G at the outlet of the heat exchanger 2 is reduced. It has the function of lowering the temperature. The second flow rate adjusting unit 63 includes an electromagnetic valve 63a, a flow rate adjusting valve 63b disposed on the downstream side of the electromagnetic valve 63a, and a pipe 63c that connects them. Similarly to the flow rate adjusting valve 62c, the flow rate adjusting valve 63c is a manually adjustable flow rate adjustable valve that can manually adjust the valve opening degree and can manually fix the valve opening degree, for example, a needle valve.

  The cooling water discharge line 7 is for discharging the cooling water C warmed by the heat exchanger 2. The cooling water discharge line 7 includes a cooling water outlet pipe 70 connected to the heat exchanger 2 and a cooling water thermometer 71 provided in the cooling water outlet pipe 70.

  The control unit 8 opens and closes the electromagnetic valves 46, 62a, and 63a at a predetermined timing. The solenoid valve 46 is automatically opened when the boiler operates and the downstream steam pressure of the pressure reducing valve 45 reaches a predetermined value, the boiler stops, and the downstream steam pressure of the pressure reducing valve 45 is smaller than the predetermined value. It will be closed automatically. The solenoid valve 62a is automatically opened before the solenoid valve 46 is opened, and is automatically closed after the solenoid valve 46 is closed. The electromagnetic valve 63a is automatically opened when an abnormality occurs when the temperature of the cooling water C in the cooling water discharge line 7 reaches a set value (70 ° C.). The electromagnetic valves 46, 62a, 63a can be opened and closed by a manual signal from the control unit 8.

  The operation state display unit 9 displays outputs from the condensate flow meter 52 and the condensate thermometer 53 (condensate flow rate and condensate temperature) and outputs from the cooling water flow meter 61 and the cooling water thermometer 71 ( The cooling water flow rate and the cooling water temperature at the outlet of the heat exchanger 2 are displayed.

  Next, setting work before use of the vapor quality monitoring apparatus 1 will be described with a specific example. In this case, saturated steam having a set steam pressure of 0.7 MPa, for example, is used for the steam S from the boiler, and tap water having an inlet temperature of 20 ° C. is used for the cooling water C. .

  First, for example, 1.5 L / min of cooling water C is supplied from the cooling water supply line 6 to the heat exchanger 2. This operation is performed by manually adjusting the opening degree of the flow rate adjustment valve 62b of the first flow rate adjustment unit 62 while viewing the indicated value of the cooling water flow meter 61 with the electromagnetic valve 62a of the first flow rate adjustment unit 62 opened. To do. In a state where the indicated value of the cooling water flow meter 61 is 1.5 L / min, the opening / closing handle of the flow rate adjusting valve 62b is locked so as not to move, and the valve opening degree is fixed.

Subsequently, the flow rate of the condensed water G is set to a constant value, for example, 100 mL / min.
When the set steam pressure of the boiler is 0.7 MPa, the steam pressure of the boiler generally varies in the range of 0.6 to 0.8 MPa. Therefore, first, the secondary pressure of the pressure reducing valve 45 of the steam supply line 4 is set to a pressure not affected by the steam pressure of the boiler, for example, 0.4 MPa. Subsequently, the solenoid valve 46 of the steam supply line 4 is opened, and the flow rate adjustment valve 51 in the condensate line 5 is manually operated while viewing the indicated value of the condensate flow meter 52 while the steam S is passed through the heat exchanger 2. Open it. Then, with the indicated value of the condensate flow meter 52 being 100 mL / min, the opening / closing handle of the flow rate adjustment valve 51 is locked so as not to move, and the valve opening is fixed. In this case, it is confirmed that the indicated value of the condensed water thermometer 53 is smaller than the upper limit value (40 ° C.) of the condensed water G.

  In the above state, even if the steam pressure of the boiler fluctuates in the range of 0.6 to 0.8 MPa, the steam pressure is fixed on the inlet side of the heat exchanger 2 by the pressure reducing valve 45, and the heat exchanger 2 The flow rate of the condensed water G is fixed by the flow rate adjusting valve 51 on the outlet side. Therefore, the flow rate of the condensed water G passing through the flow rate adjusting valve 51 is constant at 100 mL / min as originally set even if the steam pressure of the boiler fluctuates.

  On the other hand, the temperature of the condensed water G is a value obtained by subtracting the amount of heat absorbed by the heat exchanger 2 from the total amount of heat (the value obtained by multiplying the flow rate of the condensed water G by the enthalpy of the steam S) brought into the heat exchanger 2. It depends on. In this case, the enthalpy of the steam S changes when the steam pressure of the boiler changes, but the fluctuation range is small and is considered to be almost constant. Further, the heat absorption amount of the heat exchanger 2 is also considered to be constant if the inlet temperature and flow rate of the cooling water C are constant. Therefore, it is considered that the temperature of the condensed water G becomes constant as the flow rate of the condensed water G becomes constant. In order to change the temperature of the condensed water G, the flow rate of the cooling water C flowing into the heat exchanger 2 may be changed by changing the opening degree of the flow rate adjustment valve 62b of the first flow rate adjustment unit 62.

  Subsequently, even if the temperature of the condensed water G increases due to some cause (for example, a rapid increase in the inlet temperature of the cooling water C or a rapid increase in the flow rate of the condensed water G), the condensed water G remains at the upper limit value ( (40 ° C.) will be described below.

  For example, the pressure of the steam S is 0.7 MPa, the flow rate of the condensed water G is 100 mL / min, the temperature of the condensed water G is 25 ° C., the flow rate of the cooling water C is 1.5 L / min, and the inlet temperature of the cooling water C is 20 In the case of ° C, the outlet temperature of the cooling water C is about 62 ° C. On the other hand, when the temperature of the condensed water G reaches the upper limit (40 ° C.) due to the rise in the inlet temperature of the cooling water C in the above state, the outlet temperature of the cooling water C of the heat exchanger 2 rises to nearly 80 ° C. To do. Moreover, even when the temperature of the condensed water G reaches the upper limit (40 ° C.) due to the increase in the flow rate of the condensed water G in the above state, the outlet temperature of the cooling water C of the heat exchanger 2 is close to 80 ° C. To rise. Therefore, when the outlet temperature of the cooling water C becomes abnormal, for example, at a set temperature of 70 ° C., a countermeasure is required to prevent the temperature of the condensed water G from exceeding the upper limit value thereafter.

  Therefore, at the time of such an abnormality, the flow rate of the cooling water C is set to, for example, 2.5 L / min. In this case, for example, when the inlet temperature of the cooling water C is increased by 15 ° C. to 35 ° C., the outlet temperature of the condensed water G is also increased by 15 ° C. to 40 ° C., but the outlet temperature of the cooling water C is approximately 60 ° C. And the heat transfer coefficient of the heat exchanger 2 increases as the flow rate of the cooling water C increases, so that the temperature of the condensed water G is prevented from exceeding the upper limit temperature (40 ° C.). In this case, for example, even when the flow rate of the condensed water G is increased to 150 mL / min, the temperature of the condensed water G is prevented from exceeding the upper limit temperature (40 ° C.).

  In order to set the flow rate of the cooling water C to the heat exchanger 2 to 2.5 L / min, the second flow rate adjustment unit 63 may be used together with the first flow rate adjustment unit 62 in the cooling water supply line 6. That is, the instruction of the cooling water flow meter 61 with the electromagnetic valve 63a of the second flow rate adjustment unit 63 opened together with the electromagnetic valve 62a of the first flow rate adjustment unit 62 for which the opening adjustment of the flow rate adjustment valve 62b has been completed. While checking the value, the flow rate adjustment valve 63b of the second flow rate adjustment unit 63 is manually opened. Then, when the indicated value of the coolant flow meter 61 becomes 2.5 L / min, the opening degree of the flow rate adjustment valve 63b may be fixed.

Next, operational effects of the vapor quality monitoring apparatus 1 will be described.
When the boiler operates and the steam pressure on the downstream side of the pressure reducing valve 45 of the steam supply line 4 reaches, for example, near 0.4 MPa, first, the electromagnetic valve 62a of the first flow rate adjusting unit 62 in the cooling water supply line 6 is turned on. Opened and the cooling water C is supplied into the heat exchanger 2. After a certain period of time, the solenoid valve 46 of the steam supply line 4 is opened and the steam S is supplied into the heat exchanger 2. Accordingly, the heat exchanger 2 is supplied with the cooling water C at a predetermined flow rate (1.5 L / min), and the steam S supplied to the heat exchanger 2 is supplied by the cooling water C with a predetermined flow rate ( (100 mL / min) until the condensed water G reaches a predetermined temperature. The condensed water G that has exited the heat exchanger 2 is supplied to the measuring device 3 through the condensed water line 5, and the measuring device 3 measures the dissolved oxygen concentration, the electrical conductivity, and the pH. The value is recorded and displayed in the display recording unit 33. Then, the condensed water G for which the measurement has been completed is discharged from the discharge unit 34 to the outside.

  In the above state, even if the pressure of the steam S from the boiler fluctuates, the steam S is decompressed by the decompression valve 45 to a pressure that is not affected by the steam pressure of the boiler and supplied to the heat exchanger 2. Therefore, the flow rate adjustment valve 51 in the condensed water line 5 is not affected by the pressure fluctuation of the steam S. Therefore, the condensed water G that has passed through the flow rate adjusting valve 51 is always supplied to the measuring device 3 at a constant flow rate. Moreover, since the supply temperature and supply flow rate of the cooling water C to the heat exchanger 2 are constant and the flow rate of the condensed water G is constant, the temperature of the condensed water G is also constant. The measurement device 3 is always supplied at a constant temperature. Therefore, based on the water quality value (dissolved oxygen concentration value, electrical conductivity value, pH value) of the condensed water G measured over a long period of time by the measuring device 3, the amount of impurities in the steam S during this period is determined. It can be judged with high accuracy.

  Subsequently, when the operation of the boiler is stopped and the steam pressure on the secondary side of the outlet of the pressure reducing valve 45 falls below 0.3 MPa, the electromagnetic valve 46 of the steam supply line 4 is closed, and after a certain period of time, the cooling water In the supply line 6, the electromagnetic valve 62 a of the first flow rate adjustment unit 62 is closed.

  On the other hand, when the temperature of the cooling water C in the cooling water discharge line 7 reaches 70 ° C. for some reason during the operation of the boiler, the temperature of the condensed water G approaches the upper limit value. The electromagnetic valve 63 a is opened, and the cooling water C is supplied to the heat exchanger 2 not only from the first flow rate adjustment unit 62 but also from the second flow rate adjustment unit 63. For this reason, a total of 2.5 L / min of cooling water C is supplied to the heat exchanger 2, the temperature of the cooling water C in the cooling water discharge line 7 is lowered, and the temperature of the condensed water G is also lowered. The temperature is prevented from reaching the upper limit. In this case, an alarm may be issued so that the operator can take subsequent measures.

  Further, while the boiler is stopped, the steam S in the steam supply line 4 continuing from the boiler is cooled and condensed in the steam supply line 4 as condensed drainage. For this reason, when the operation of the boiler is resumed, the solenoid valve 4 of the steam supply line 4 is opened, and the steam S is supplied to the heat exchanger 2, the condensed waste water in the steam supply line 4 becomes the steam supply line. 4 moves to the heat exchanger 2 side together with sludge such as corrosion products generated in 4 to try to block the steam filter 44. However, the condensed waste water in the steam sampling pipe 40 which is the main part of the steam supply line 4 does not flow into the branch pipe 41 branched from the steam sampling pipe 40 to the heat exchanger 2 side. It flows to the downward piping portion 40a side of the end portion, passes through the steam trap 42, and is discharged to the outside by the drain piping 42.

  For this reason, when the operation of the boiler is resumed, the steam filter 44 of the steam supply line 4 is blocked, and the number of cleaning or replacement of the steam filter 44 does not increase, and the number of flushing of the steam supply line 4 does not increase. There is no problem in monitoring the quality of the steam S using the apparatus 1.

  As described above, in the steam quality monitoring apparatus 1, the steam trap 42 that discharges the condensed waste water in the steam sampling pipe 40 is provided at the end of the steam sampling pipe 40 from the boiler that supplies the steam S to the heat exchanger 2. The steam sampling pipe 40 and the heat exchanger 2 are connected by a branch pipe 41 from the steam sampling pipe 40 that prevents the condensed waste water in the steam sampling pipe 40 from flowing in.

  Therefore, in this steam quality monitoring device 1, sludge such as corrosion products generated in the steam sampling pipe 40 from the boiler can be discharged to the outside through the steam trap 42 together with the condensed waste water. Therefore, continuous and stable monitoring of steam quality will be possible without hindering the monitoring work of steam quality.

  Further, in this steam quality monitoring device 1, a pressure reducing valve for reducing the pressure of the steam S at the inlet of the heat exchanger 2 to a constant pressure that is not affected by the pressure fluctuation by the boiler is provided in the steam supply line 4 at the inlet of the heat exchanger 2. 45, a condensate flow meter 52, and a manual flow rate adjusting valve 51 in which the valve opening is manually set and fixed are provided in the condensate line 5 between the heat exchanger 2 and the measuring device 3. Provided.

  Therefore, in this steam quality monitoring device 1, even if the steam pressure of the boiler fluctuates, the flow rate of the condensed water G flowing to the measuring device 3 side using the inexpensive pressure reducing valve 45 and the inexpensive manual flow rate adjusting valve 51. Therefore, it is not necessary to provide an expensive flow control valve that automatically keeps the condensate flow rate constant, reducing equipment costs and reducing equipment operation troubles. . Moreover, in this vapor quality monitoring apparatus 1, since the flow volume of the condensed water G can be kept constant reliably, the water quality value of the condensed water G measured by the measuring apparatus 3 also from a viewpoint of the constant flow volume of the condensed water G. Based on the above, it is possible to accurately determine the amount of impurities in the vapor S.

  Further, in this vapor quality monitoring device 1, a cooling water thermometer 71 is provided in the cooling water discharge line 7, a cooling water flow meter 61 is provided in the cooling water supply line 6, and heat is exchanged in the cooling water supply line 6. The valve opening is manually set and fixed so that the cooling water C flows through the heat exchanger 2 by an amount such that the temperature of the cooling water C at the outlet of the heater 2 is smaller than a predetermined set value. A first flow rate adjustment unit 62 in which a flow rate adjustment valve 62b of the type and an electromagnetic valve 62a opened at the start of operation of the boiler are arranged in series, and the first flow rate adjustment unit 62 is provided in the cooling water supply line 6. In parallel, when the temperature of the cooling water C at the outlet of the heat exchanger 2 reaches the set value and the temperature of the condensed water G approaches the upper limit value, it is added to the first flow rate adjustment unit 62 and only a predetermined amount is added. Cooling water C to heat exchanger 2 As described above, a second flow rate adjustment unit 63 is provided in which a manual flow rate adjustment valve 63b in which the valve opening is manually set and fixed and an electromagnetic valve 63a that is opened in the event of an abnormality are arranged in series. Yes.

  Therefore, in the steam quality monitoring apparatus 1, even if the steam pressure of the boiler fluctuates, the first and second flow rate adjustment units including the inexpensive solenoid valves 62a and 63a and the inexpensive manual flow rate adjustment valves 62b and 63b are provided. 62 and 63 can be used to keep the temperature of the condensed water G flowing to the measuring device 3 side constant and cope with the abnormally high temperature of the cooling water C at the outlet of the heat exchanger 2. For this reason, in this vapor quality monitoring apparatus 1, it is not necessary to provide an expensive flow rate adjusting valve that automatically keeps the condensate temperature constant, and it is possible to reduce the cost of the equipment and to reduce the operation trouble of the equipment. Can do. Of course, in this vapor quality monitoring device 1, the temperature of the condensed water G can be kept constant, so that the temperature of the condensed water G is also constant, based on the water quality value of the condensed water G measured by the measuring device 3. Thus, it is possible to accurately determine the amount of impurities in the vapor S.

  In this vapor quality monitoring device 1, only two sets of flow rate adjusting units are provided in the cooling water supply line 6, but the flow rate used when the temperature of the cooling water C at the outlet of the heat exchanger 2 exceeds the set value is abnormal. Three or more sets of flow rate control units may be provided in the cooling water supply line 6 so that there are a plurality of adjustment units.

  Further, the cooling water flow meter 61 provided in the cooling water supply line 6 may be provided in the cooling water discharge line 7.

  Further, the condensate line 5 may not be provided with the condensate thermometer 53, and the temperature of the condensate G may be a thermometer provided in the electric conductivity meter 31 or the pH meter 32 of the measuring device 3.

  Next, specific examples regarding the vapor quality monitoring apparatus 1 will be described.

  In some factories, steam S from the boiler is supplied as a 24-hour utility, but the boiler is shut down for about two days once every three months. When the conventional steam quality monitoring device 100 is used, sludge such as corrosion products generated in the steam pipe 107 when the boiler resumes operation, together with the condensed waste water in the steam pipe 101, the heat exchanger 101 side. The steam filter immediately before the heat exchanger 101 was closed. For this reason, replacement of the filter part of the steam filter and flushing of the steam pipe 101 were performed, and the use of the steam quality monitoring apparatus 100 was resumed.

  After that, the steam pipe 107 of the steam quality monitoring device 100 is provided with a steam trap 43 at the lower end of the downward pipe 40a at the end of the steam sampling pipe 40, like the steam quality monitoring apparatus 1, and The heat exchanger 2 was modified to be connected by a branch pipe 41 branched from the steam sampling pipe 40 so that the condensed waste water in the steam sampling pipe 40 does not flow. After the remodeling, when the operation of the boiler is resumed, the sludge in the steam sampling pipe 40 has moved to the heat exchanger 2 side together with the condensed waste water as before, but this movement is blocked by the branch pipe 44, and this sludge and The condensed waste water was discharged to the outside through the steam trap 43 at the end of the steam sampling pipe 40. For this reason, the steam filter 44 provided in the branch pipe 41 is not clogged, and there is no influence of the subsequent shutdown of the boiler. Monitoring was possible.

  In a factory equipped with a boiler having a vapor pressure of 0.7 MPa (the vapor pressure varies in the range of about 0.6 to 0.8 MPa), the following vapor quality monitoring device was used. Although this vapor quality monitoring device may be somewhat different from the vapor quality monitoring device 1, the same reference numerals as those of the vapor quality monitoring device 1 are attached to the corresponding parts for easy understanding. The same applies to Example 3.

(1) A pressure reducing valve 45 is installed in the steam supply line 4, and the secondary side set pressure after the pressure reducing by the pressure reducing valve 45 is set to 0.4 MPa.
(2) A condensate flow meter provided in the condensed water line 5 is provided with a manual flow rate adjusting valve 51 (needle valve) for adjusting the flow rate of the condensed water G in the condensed water line 5 at the outlet of the heat exchanger 2. While viewing the measured value of 52, the opening degree of the flow rate adjustment valve 51 was manually adjusted to set the flow rate of the condensed water G to 100 mL / min, and then the opening degree of the flow rate adjustment valve 51 was fixed.
As a result of using the above steam quality monitoring device, the flow rate of the condensed water G was stably maintained in a state of 100 mL / min despite the fluctuation of the steam pressure from the boiler. In addition, even if it changed the opening degree setting of the flow regulating valve 51 so that the flow volume of the condensed water G might be 80-120 mL / min, these flow volume was maintained stably.

In the factory described in Example 2, in addition to the above (1) and (2), a vapor quality monitoring device having the following conditions was used.
(3) Use cooling water with heat exchanger 2 inlet temperature of 20 ° C.
(4) The cooling water supply line 6 is provided with first and second flow rate adjusting units 62 and 63 arranged in parallel with a manual flow rate adjusting valve (needle valve) and a solenoid valve arranged in series. While observing the measured value of the cooling water flow meter 61 provided in the cooling water supply line 6, the opening of the flow rate adjusting valve 62b of the first flow rate adjusting unit 62 is set so that the flow rate of the cooling water C is 1.5 L / min. The flow rate of the flow rate adjustment valve 63b of the second flow rate adjustment unit 63 is set to 2.5 L / min when the flow rate of the cooling water C is adjusted to that by the flow rate adjustment valve 62b. It was manually set to be fixed.
(5) The electromagnetic valve 62a of the first flow rate adjustment unit 62 is set to automatically open at the start of operation of the boiler, and the electromagnetic valve 63a of the second flow rate adjustment unit 63 is set to the heat exchanger 2 for the cooling water C. It was set to open automatically when the outlet temperature reached 70 ° C.

  The electromagnetic valve 63a of the second flow rate adjusting unit 63 is opened when the outlet temperature of the heat exchanger 2 of the cooling water C reaches 70 ° C when the outlet temperature of the cooling water C reaches 70 ° C. By increasing the flow rate of the cooling water C to 2.5 L / min, for example, the inlet temperature of the cooling water C becomes 35 ° C. for some reason, or the flow rate of the condensed water G for some reason (usually under the above operating conditions) This is to prevent the temperature of the condensed water G from exceeding the upper limit value (40 ° C.) even when it is increased to 150 mL / min).

  When the vapor quality monitoring device is operated with only the electromagnetic valve 62a of the first flow rate adjustment unit 62 opened, the outlet temperature of the heat exchanger 2 of the cooling water C is set at a flow rate of the condensed water G of 100 mL / min. The temperature was somewhat higher than 60 ° C., and the temperature of the condensed water G was 25 ° C. and was stable. In this state, when the flow rate of the condensed water G is increased to 150 mL / min, the solenoid valve 63a of the second flow rate adjustment unit 63 is reached when the temperature of the outlet of the heat exchanger 2 of the cooling water C reaches 70 ° C. And the flow rate of the cooling water C increased from 1.5 L / min to 2.5 L / min. Thereafter, the temperature at the outlet of the heat exchanger 2 of the cooling water C dropped and stabilized from about 60 ° C., and the temperature of the condensed water G became stable at about 30 ° C. That is, when only the first flow rate adjustment unit 62 is used, the temperature of the condensed water G can be kept constant, and when both the first and second flow rate adjustment units 62 and 63 are used, Even when the flow rate of the condensed water G was 150 mL / min, the temperature of the condensed water G was not increased to the upper limit (40 ° C.).

It is a figure which shows the vapor quality monitoring apparatus which concerns on one embodiment of this invention. It is a figure which shows the conventional vapor quality monitoring apparatus.

Explanation of symbols

1 Steam quality monitoring device 2 Heat exchanger 3 Measuring device (measuring means)
4 Steam supply line (steam supply line)
5 Condensate water line 6 Cooling water supply line (refrigerant supply line)
7 Cooling water discharge line (refrigerant discharge line)
40 Steam piping (steam sampling piping)
41 Branch piping 43 Steam trap 45 Pressure reducing valve 51 Flow rate adjusting valve 61 Cooling water flow meter (flow rate measuring means)
62 First flow rate adjustment unit (first flow rate adjustment unit)
62a Solenoid valve 62b Flow adjustment valve 63 Second flow adjustment unit (second flow adjustment unit)
63a Solenoid valve 63b Flow control valve C Cooling water (refrigerant)
G Condensate S Steam

Claims (3)

The amount of impurities in the steam generated in the boiler using a heat exchanger that converts the steam from the boiler into condensed water using a refrigerant, and a measuring means that measures the quality of the condensed water from the heat exchanger In the vapor quality monitoring device that continuously monitors
Provided at the end of the steam pipe from the boiler that supplies the steam to the heat exchanger is a steam trap that discharges condensed waste water generated by condensation of the steam in the steam pipe,
A steam quality monitoring apparatus, wherein the steam pipe and the heat exchanger are connected by a branch pipe from the steam pipe so that the condensed waste water in the steam pipe does not flow into the steam pipe. A pressure reducing valve for reducing the pressure of the steam at the inlet of the heat exchanger to a constant pressure that is not affected by pressure fluctuations by the boiler is provided in the branch pipe,
In addition, the condensed water line between the heat exchanger and the measuring means is provided with a flow rate measuring means for the condensed water and a manual flow rate adjusting valve for manually setting and fixing the valve opening degree. The vapor quality monitoring device according to claim 1. The refrigerant temperature measuring means is provided in the refrigerant discharge line for the heat exchanger, and the refrigerant flow measuring means is provided in the refrigerant supply line or the exhaust line for the heat exchanger,
In addition, the valve opening is manually set so that the refrigerant flows through the heat exchanger in an amount such that the refrigerant temperature at the outlet of the heat exchanger is smaller than a predetermined set value. A first flow rate adjustment unit is provided in which a manual flow rate adjustment valve that is fixed and an electromagnetic valve that is opened when the boiler starts operation are arranged in series,
Further, in parallel with the refrigerant flow line and the first flow rate adjustment unit, when the refrigerant temperature at the outlet of the heat exchanger reaches the set value and the temperature of the condensed water approaches an upper limit value, In addition to the first flow rate adjustment unit, a manual flow rate adjustment valve in which the valve opening is manually set and fixed so that the refrigerant flows through the heat exchanger by a predetermined amount; The vapor quality monitoring device according to claim 2, further comprising a second flow rate adjusting unit in which an electromagnetic valve to be opened is arranged in series.

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