An apparatus for recycling hydrazine hydrate

Abstract

The utility model discloses a device of recycling hydrazine hydrate, with the system device of the pressure -reducing rectification mechanism, condensation water separation mechanism and cyclic collection mechanism composition carries out the process of feeding distillation, condensation water separation, cyclic collection. The utility model discloses through low -temperature pressure -reducing rectification avoids the decomposition explosion of hydrazine hydrate under high temperature, and the process safety is significantly promoted. By introducing the rectifying column after the stratification toluene, the entrainment of hydrazine hydrate in the steam-out liquid is reduced, the hydrazine hydrate residual quantity in the stratified wastewater is further reduced, more than 80% of the traditional method is reduced, and the hydrazine hydrate recovery rate is significantly improved. The water separation mechanism automatically separates toluene and wastewater, and the degree of automation is high. The stratified toluene is recycled, the raw material cost is reduced, the wastewater is directly discharged after reaching the standard, the subsequent sewage treatment cost is reduced, and it is more economic and environmental protection.

Description

Technical Field

[0001] This utility model relates to the field of hydrazine hydrate recycling technology, and more specifically, it relates to a device for recycling hydrazine hydrate. Background Technology

[0002] Prothioconazole is a triazole thione fungicide mainly used to control numerous diseases in crops such as cereals, wheat, and beans. The intermediate hydrazine compound of prothioconazole is mainly synthesized using the hydrazine hydrate method and the triazole method. Because the triazole method has harsh processing conditions, low yield, and relatively poor product quality, the hydrazine hydrate method is the more commonly used process both domestically and internationally.

[0003] Hydrazine hydrate (N₂H₄H₂O), also known as hydrated ammonia, is a strong base and hygroscopic. Under normal pressure, hydrazine can form an azeotrope with water, and the liquid hydrazine hydrate exists as a dimer, which is a core raw material in the synthesis of prothioconazole. However, at current levels, hydrazine hydrate can only be used in excess for synthesis, resulting in a large amount of low-concentration hydrazine hydrate remaining in the system after the reaction. Direct discharge of this hydrazine would place a severe burden on wastewater treatment systems due to its high chemical oxygen demand (COD). The current mainstream recovery method is vacuum distillation, but this method has the following drawbacks:

[0004] (1) Poor safety: hydrazine hydrate is easily decomposed at high temperatures to produce gases such as NH3 and N2, and has an explosion risk when concentrated to a certain concentration;

[0005] (2) Low efficiency. During the distillation process, hydrazine hydrate is easily carried away by water vapor, resulting in the distillate still containing a high concentration of hydrazine hydrate, which cannot meet the emission standards.

[0006] (3) Insufficient stability, process fluctuations can easily cause hydrazine decomposition, affecting the purity of the recovery. Utility Model Content

[0007] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a device for recovering hydrazine hydrate, thereby solving one or more of the above-mentioned problems.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] An apparatus for recovering hydrazine hydrate, comprising:

[0010] A vacuum distillation unit for vacuum distilling low concentrations of hydrazine hydrate and toluene;

[0011] The condensation and water separation mechanism is connected to the vacuum distillation mechanism to condense, liquefy and separate the distilled gas phase.

[0012] The circulating collection mechanism is connected to the condensate separation mechanism to classify and receive the stratified objects. The different classified objects are introduced into the vacuum distillation mechanism or discharged after meeting the standards.

[0013] Furthermore, the vacuum distillation mechanism includes a distillation kettle and a distillation column connected in sequence. Both the distillation kettle and the distillation column are made of stainless steel, and the height and diameter of the distillation column are not unique.

[0014] Furthermore, the condensate distribution mechanism includes

[0015] The main condenser is connected to the distillation column;

[0016] A vacuum condenser, which is connected to a circulation collection mechanism via a balance pipe with a switch valve and an external vacuum pipeline;

[0017] The pressure reducer is connected to both the main condenser and the vacuum condenser, and also to the distributor;

[0018] The separator is connected to a pressure reducer and also to a circulating collection mechanism.

[0019] Furthermore, the recycling mechanism includes

[0020] Toluene storage tank, which is connected to a recovery pipe and equipped with corresponding valves;

[0021] The wastewater storage tank is connected to a distributor via a discharge pipe with a regulating valve, and is also connected to a vacuum condenser and an external drain pipe.

[0022] Furthermore, the toluene storage tank is connected to the distillation column via a recovery pump;

[0023] The separator is equipped with an interface meter, which is electrically connected to the regulating valve. In summary, this invention has the following advantages: Low-temperature, reduced-pressure distillation avoids the decomposition and explosion of hydrazine hydrate at high temperatures, significantly improving process safety; introducing toluene after stratification into the distillation column reduces the entrainment of hydrazine hydrate in the distillate, further reducing the residual amount of hydrazine hydrate in the stratified wastewater by more than 80% compared to traditional methods, and significantly improving the hydrazine hydrate recovery rate; the water separation mechanism automatically separates toluene and wastewater, achieving a high degree of automation; the stratified toluene is recycled, reducing raw material costs; and the wastewater is directly discharged after meeting standards, reducing subsequent wastewater treatment costs, making it more economical and environmentally friendly. Attached Figure Description

[0024] Figure 1 A schematic diagram of one embodiment of this utility model;

[0025] Figure 2 A process flow diagram for one embodiment of this utility model.

[0026] In the diagram: 1. Distillation kettle; 2. Distillation column; 3. Main condenser; 4. Vacuum condenser; 5. Balance pipe; 6. Vacuum pipeline; 7. Pressure reducer; 8. Separator; 9. Recovery pipe; 10. Toluene storage tank; 11. Wastewater storage tank; 12. Recovery pump; 13. Interface gauge; 14. Control valve; 15. Drain pipe; 1-1. Bottom valve; 1-2. Layered sight glass; 1-3. Layered manual valve. Detailed Implementation

[0027] Example 1:

[0028] The following is in conjunction with the appendix Figure 1-2 The present invention will be described in further detail below.

[0029] An apparatus for recovering hydrazine hydrate, such as Figure 1 As shown, it mainly consists of a vacuum distillation unit, a condensation and water separation unit, and a circulation collection unit connected in sequence. It sequentially performs vacuum distillation of low-concentration hydrazine hydrate wastewater, liquefaction and stratification of the gas phase after distillation, classification and reception of the stratified waste, recycling and harmless discharge.

[0030] The vacuum distillation unit comprises a distillation kettle 1 and a distillation column 2 connected in sequence. The specifications of distillation kettle 1 and distillation column 2 are determined according to actual production needs. Both distillation kettle 1 and distillation column 2 are made of stainless steel. The volume of the distillation kettle is 3000L. The diameter and height of distillation column 2 are DN800×H3000mm (tangent-tangent). The column body and internal parts are made of SS316L stainless steel, and the packing is CY700 wire mesh packing (SS316L) with an H-packing of 2500mm.

[0031] The condensation and water distribution mechanism includes a main condenser 3 and a vacuum condenser 4 installed in parallel, as well as a pressure reducer 7 and a separator 8. The main condenser 3 is connected to the distillation column 2, and the vacuum condenser 4 is connected to the external vacuum pipeline 6. Both condensers are connected to the pressure reducer 7 at the end. The separator 8 is directly connected to the pressure reducer 7 and is also connected to the wastewater storage tank 11 of the circulation collection mechanism.

[0032] The recycling system includes a toluene storage tank 10 and a wastewater storage tank 11. The wastewater storage tank 11 is connected to the piping system of the vacuum condenser 4 via a balance pipe 5 with a valve. A recovery pipe 9 is connected to the toluene storage tank 10 via a pipe with a switch valve. The toluene storage tank 10 is connected to the distillation column 2 via a recovery pump 12. The wastewater storage tank 11 is connected to the separator 8 via a discharge pipe 15 with a regulating valve 14. The wastewater storage tank 11 is also externally connected to a drain pipe. The separator 8 is equipped with an interface gauge 13, which is electrically connected to the regulating valve 14. The interface gauge 13 guides the operation of the regulating valve 14 based on relevant parameters inside the separator 8.

[0033] Distillation vessel 1 receives external feed and subsequently receives toluene returned from distillation column 2. Distillation column 2 purifies the mixture of toluene, water, and hydrazine hydrate distilled from distillation vessel 1 and subsequently returns toluene from toluene storage tank 10 via recovery pump 12. Toluene storage tank 10 receives and stores stratified toluene from recovery pipe 9. The vapor phase from vacuum distillation in distillation column 2 enters main condenser 3. With the assistance of vacuum condenser 4, the entire system remains under vacuum, introducing the liquefied material into pressure reducer 7 and directly into separator 8 to separate toluene and waste liquid of different densities. The waste liquid enters wastewater storage tank 11, and the toluene enters recovery pipe 9.

[0034] The method for recovering hydrazine hydrate using the above-described apparatus, such as Figure 2 As shown, the steps are as follows:

[0035] S1. Feeding and distillation: 2000 kg of low-concentration hydrazine hydrate (30%) and 500 kg of toluene are added sequentially to distillation vessel 1, and vacuum distillation is carried out using distillation column 2.

[0036] The conditions for vacuum distillation in step S1 are a pressure of -0.07 MPa and a temperature of 60-80℃.

[0037] S2. Condensation and water separation: The toluene, water and trace amount of hydrazine hydrate gas phase distilled under reduced pressure in step S1 are liquefied by the main condenser 3 and then enter the separator 8 through the pressure reducer 7. Toluene and wastewater are automatically separated by density difference.

[0038] In step S2, a vacuum line 6 and a vacuum condenser 4 are introduced to maintain the vacuum state and assist the water condensation process, and the internal pressure is maintained by means of a balance pipe 5.

[0039] S3. Circulation and collection: The toluene separated in step S2 is collected into toluene storage tank 10 and sent back to the top of distillation column 2 by means of recovery pump 12.

[0040] In step S3, the toluene separated by stratification is returned to the top of distillation column 2 to suppress the entrainment of hydrazine hydrate by water vapor through extractive distillation, thereby improving the hydrazine hydrate recovery rate; the toluene recycled back to distillation kettle 1 can gradually increase the hydrazine hydrate concentration to 64%;

[0041] Stop distillation. Reactor 1 separates the lower layer of 64% hydrazine hydrate through the bottom valve 1-1, the layering sight glass 1-2, and the layering manual valve 1-3. The upper toluene layer is recycled to the next stage. Specifically, when the hydrazine hydrate reaches the target concentration, the bottom valve 1-1 is opened, the opening of the layering manual valve 1-3 is adjusted, and the layering interface is observed through the layering sight glass 1-2 to separate the lower layer of high-concentration hydrazine hydrate. After the layering is completed, the bottom valve 1-1 is closed, and the upper toluene layer is left in the reactor for reuse.

[0042] The wastewater separated in step S2 is collected into wastewater storage tank 11. The concentration of hydrazine hydrate in the wastewater is tested. Once it meets the standard, it is directly introduced into the sewage treatment system through the drainage pipeline.

[0043] The standard is met if the residual hydrazine hydrate in the wastewater in step S3 is less than 0.01% w / w.

[0044] Example 2:

[0045] An apparatus for recovering hydrazine hydrate, such as Figure 1 As shown, it mainly consists of a vacuum distillation unit, a condensation and water separation unit, and a circulation collection unit connected in sequence. It sequentially performs vacuum distillation of low-concentration hydrazine hydrate wastewater, liquefaction and stratification of the gas phase after distillation, classification and reception of the stratified waste, recycling and harmless discharge.

[0046] The vacuum distillation unit comprises a distillation kettle 1 and a distillation column 2 connected in sequence. The specifications of distillation kettle 1 and distillation column 2 are determined according to actual production needs. Both distillation kettle 1 and distillation column 2 are made of stainless steel. The volume of the distillation kettle is 3000L. The diameter and height of distillation column 2 are DN800×H4000mm (tangent-tangent). The column body and internal parts are made of SS316L stainless steel, and the packing is CY700 wire mesh packing (SS316L) with an H-packing of 3500mm.

[0047] The condensation and water distribution mechanism includes a main condenser 3 and a vacuum condenser 4 installed in parallel, as well as a pressure reducer 7 and a separator 8. The main condenser 3 is connected to the distillation column 2, and the vacuum condenser 4 is connected to the external vacuum pipeline 6. Both condensers are connected to the pressure reducer 7 at the end. The separator 8 is directly connected to the pressure reducer 7 and is also connected to the wastewater storage tank 11 of the circulation collection mechanism.

[0048] The recycling system includes a toluene storage tank 10 and a wastewater storage tank 11. The wastewater storage tank 11 is connected to the piping system of the vacuum condenser 4 via a balance pipe 5 with a valve. A recovery pipe 9 is connected to the toluene storage tank 10 via a pipe with a switch valve and is equipped with a corresponding valve. The toluene storage tank 10 is also connected to the distillation column 2 via a recovery pump 12. The wastewater storage tank 11 is connected to the separator 8 via a discharge pipe 15 with a regulating valve 14. The wastewater storage tank 11 is also externally connected to a drain pipe. The separator 8 is equipped with an interface gauge 13, which is electrically connected to the regulating valve 14. The interface gauge 13 guides the operation of the regulating valve 14 based on relevant parameters within the separator 8.

[0049] Distillation vessel 1 receives external feed and subsequently receives toluene returned from distillation column 2. Distillation column 2 purifies the mixture of toluene, water, and hydrazine hydrate distilled from distillation vessel 1 and subsequently returns toluene from toluene storage tank 10 via recovery pump 12. Toluene storage tank 10 receives and stores stratified toluene from recovery pipe 9. The vapor phase from vacuum distillation in distillation column 2 enters main condenser 3. With the assistance of vacuum condenser 4, the entire system remains under vacuum, introducing the liquefied material into pressure reducer 7 and directly into separator 8 to separate toluene and waste liquid of different densities. The waste liquid enters wastewater storage tank 11, and the toluene enters recovery pipe 9.

[0050] The method for recovering hydrazine hydrate using the above-described apparatus, such as Figure 2 As shown, the steps are as follows:

[0051] S1. Feeding and distillation: 2000 kg of low-concentration hydrazine hydrate (30%) and 500 kg of toluene are added sequentially to distillation vessel 1, and vacuum distillation is carried out using distillation column 2.

[0052] The conditions for vacuum distillation in step S1 are a pressure of -0.07 MPa and a temperature of 60-80℃.

[0053] S2. Condensation and water separation: The toluene, water and trace amount of hydrazine hydrate gas phase distilled under reduced pressure in step S1 are liquefied by the main condenser 3 and then enter the separator 8 through the pressure reducer 7. Toluene and wastewater are automatically separated by density difference.

[0054] In step S2, a vacuum line 6 and a vacuum condenser 4 are introduced to maintain the vacuum state and assist the water condensation process, and the internal pressure is maintained by means of a balance pipe 5.

[0055] S3. Circulation and collection: The toluene separated in step S2 is collected into toluene storage tank 10 and sent back to the top of distillation column 2 by means of recovery pump 12.

[0056] In step S3, the toluene separated by separation is returned to the top of distillation column 2 to suppress the entrainment of hydrazine hydrate by water vapor through extractive distillation, thereby improving the hydrazine hydrate recovery rate; the toluene recycled back to distillation kettle 1 can gradually increase the hydrazine hydrate concentration to 75%;

[0057] Stop distillation. Reactor 1 separates the lower layer of 75% hydrazine hydrate through the bottom valve 1-1, the layering sight glass 1-2, and the layering manual valve 1-3. The upper toluene layer is recycled to the next stage. Specifically, when the hydrazine hydrate reaches the target concentration, the bottom valve 1-1 is opened, the opening of the layering manual valve 1-3 is adjusted, and the layering interface is observed through the layering sight glass 1-2 to separate the lower layer of high-concentration hydrazine hydrate. After the layering is completed, the bottom valve 1-1 is closed, and the upper toluene layer is left in the reactor for reuse.

[0058] The wastewater separated in step S2 is collected into wastewater storage tank 11. The concentration of hydrazine hydrate in the wastewater is tested. Once it meets the standard, it is directly introduced into the sewage treatment system through the drainage pipeline.

[0059] The standard is met if the residual hydrazine hydrate in the wastewater in step S3 is less than 0.01% w / w.

[0060] Example 3:

[0061] An apparatus for recovering hydrazine hydrate, such as Figure 1 As shown, it mainly consists of a vacuum distillation unit, a condensation and water separation unit, and a circulation collection unit connected in sequence. It sequentially performs vacuum distillation of low-concentration hydrazine hydrate wastewater, liquefaction and stratification of the gas phase after distillation, classification and reception of the stratified waste, recycling and harmless discharge.

[0062] The vacuum distillation unit comprises a distillation kettle 1 and a distillation column 2 connected in sequence. The specifications of distillation kettle 1 and distillation column 2 are determined according to actual production needs. Both distillation kettle 1 and distillation column 2 are made of stainless steel. The volume of the distillation kettle is 3000L. The diameter and height of distillation column 2 are DN800×H4000mm (tangent-tangent). The column body and internal parts are made of SS316L stainless steel, and the packing is CY700 wire mesh packing (SS316L) with an H-packing of 3500mm.

[0063] The condensation and water distribution mechanism includes a main condenser 3 and a vacuum condenser 4 installed in parallel, as well as a pressure reducer 7 and a separator 8. The main condenser 3 is connected to the distillation column 2, and the vacuum condenser 4 is connected to the external vacuum pipeline 6. Both condensers are connected to the pressure reducer 7 at the end. The separator 8 is directly connected to the pressure reducer 7 and is also connected to the wastewater storage tank 11 of the circulation collection mechanism.

[0064] The recycling system includes a toluene storage tank 10 and a wastewater storage tank 11. The wastewater storage tank 11 is connected to the piping system of the vacuum condenser 4 via a balance pipe 5 with a valve. A recovery pipe 9 is connected to the toluene storage tank 10 via a pipe with a switch valve and is equipped with a corresponding valve. The toluene storage tank 10 is also connected to the distillation column 2 via a recovery pump 12. The wastewater storage tank 11 is connected to the separator 8 via a discharge pipe 15 with a regulating valve 14. The wastewater storage tank 11 is also externally connected to a drain pipe. The separator 8 is equipped with an interface gauge 13, which is electrically connected to the regulating valve 14. The interface gauge 13 guides the operation of the regulating valve 14 based on relevant parameters within the separator 8.

[0065] Distillation vessel 1 receives external feed and subsequently receives toluene returned from distillation column 2. Distillation column 2 purifies the mixture of toluene, water, and hydrazine hydrate distilled from distillation vessel 1 and subsequently returns toluene from toluene storage tank 10 via recovery pump 12. Toluene storage tank 10 receives and stores stratified toluene from recovery pipe 9. The vapor phase from vacuum distillation in distillation column 2 enters main condenser 3. With the assistance of vacuum condenser 4, the entire system remains under vacuum, introducing the liquefied material into pressure reducer 7 and directly into separator 8 to separate toluene and waste liquid of different densities. The waste liquid enters wastewater storage tank 11, and the toluene enters recovery pipe 9.

[0066] The method for recovering hydrazine hydrate using the above-described apparatus, such as Figure 2 As shown, the steps are as follows:

[0067] S1. Feeding and distillation: 2000 kg of low-concentration hydrazine hydrate (45%) and 500 kg of toluene are added sequentially to distillation vessel 1, and vacuum distillation is carried out using distillation column 2.

[0068] The conditions for vacuum distillation in step S1 are a pressure of -0.08 MPa and a temperature of 60-80℃.

[0069] S2. Condensation and water separation: The toluene, water and trace amount of hydrazine hydrate gas phase distilled under reduced pressure in step S1 are liquefied by the main condenser 3 and then enter the separator 8 through the pressure reducer 7. Toluene and wastewater are automatically separated by density difference.

[0070] In step S2, a vacuum line 6 and a vacuum condenser 4 are introduced to maintain the vacuum state and assist the water condensation process, and the internal pressure is maintained by means of a balance pipe 5.

[0071] S3. Circulation and collection: The toluene separated in step S2 is collected into toluene storage tank 10 and sent back to the top of distillation column 2 by means of recovery pump 12.

[0072] In step S3, the toluene separated by separation is returned to the top of distillation column 2 to suppress the entrainment of hydrazine hydrate by water vapor through extractive distillation, thereby improving the hydrazine hydrate recovery rate; the toluene recycled back to distillation kettle 1 can gradually increase the hydrazine hydrate concentration to 80%;

[0073] Stop distillation. Reactor 1 separates the lower layer of hydrazine hydrate with a concentration of 80% through the bottom valve 1-1, the layering sight glass 1-2, and the layering manual valve 1-3. The upper toluene layer is recycled to the next stage. Specifically, when the hydrazine hydrate reaches the target concentration, the bottom valve 1-1 is opened, the opening of the layering manual valve 1-3 is adjusted, and the layering interface is observed through the layering sight glass 1-2 to separate the lower layer of high-concentration hydrazine hydrate. After the layering is completed, the bottom valve 1-1 is closed, and the upper toluene layer is left in the reactor for reuse.

[0074] The wastewater separated in step S2 is collected into wastewater storage tank 11. The concentration of hydrazine hydrate in the wastewater is tested. Once it meets the standard, it is directly introduced into the sewage treatment system through the drainage pipeline.

[0075] The standard is met if the residual hydrazine hydrate in the wastewater in step S3 is less than 0.01% w / w.

[0076] Example 4

[0077] Wastewater from a selected batch of prothioconazole synthesis was fed into a 3000L distillation vessel 1. The wastewater contained 20% hydrazine hydrate and weighed 2000 kg. Then, 500 kg of toluene was pumped in. The diameter and height of distillation column 2 were DN800 × H3000 mm (tangent-tangent). The column body and internal components were made of SS316L stainless steel, and the packing was CY700 wire mesh packing (SS316L) with an H-packing of 2500 mm. The pressure reduction system was activated, and the solution was passed through distillation column 2 at -0.08 MPa pressure and 75°C. The distilled vapor phase, after condensation, entered a water separator with a density of 0.87 g / cm³. 3 Toluene and a density of 1 g / cm³ 3 The water automatically separates into layers. Toluene is pumped back to the top of distillation column 2 via toluene storage tank 10. Wastewater is discharged after the hydrazine content is tested and found to be no higher than 0.01%. After 6 hours of continuous distillation, the concentration of hydrazine hydrate in the reactor reaches 75%, at which point the process is stopped. After cooling, the layers separate, and the recovered hydrazine hydrate is reused in the synthesis process of prothioconazole hydrazine compounds. The toluene in the reactor is reserved for the next batch of concentrated hydrazine hydrate.

[0078] By optimizing the distillation process and water separation mechanism, the problems of low hydrazine hydrate recovery efficiency, poor safety, and high wastewater residue in existing technologies are solved. By continuously reducing the water content of the system through toluene reflux, the concentration of hydrazine hydrate in distillation vessel 1 is gradually increased to 64%~80%, yielding high-concentration hydrazine hydrate that can be directly applied to the synthesis process of prothioconazole hydrazine compounds. The single-batch hydrazine hydrate recovery rate exceeds 95%, and wastewater treatment costs are reduced by 60%, demonstrating significant economic and environmental benefits. It should be noted that this specific embodiment is merely an explanation of the present invention and is not intended to limit it. Those skilled in the art can make modifications to this embodiment without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they fall within the scope of the claims of the present invention.

Claims

1. An apparatus for recovering hydrazine hydrate, characterized in that: include A vacuum distillation unit for vacuum distilling low concentrations of hydrazine hydrate and toluene; The condensation and water separation mechanism is connected to the vacuum distillation mechanism to condense, liquefy, and separate the distilled gas phase into layers. The circulating collection mechanism is connected to the condensate separation mechanism to classify and receive the stratified objects. The different classified objects are introduced into the vacuum distillation mechanism or discharged after meeting the standards. The vacuum distillation unit includes a distillation kettle and a distillation column connected in sequence. Both the distillation kettle and the distillation column are made of stainless steel. The height and diameter of the distillation column are not unique. Condensation water distribution mechanism includes The main condenser is connected to the distillation column; A vacuum condenser, which is connected to a circulation collection mechanism via a balance pipe with a switch valve and an external vacuum pipeline; The pressure reducer is connected to both the main condenser and the vacuum condenser, and also to the distributor; The separator is connected to a pressure reducer and also to a circulating collection mechanism; The recycling collection mechanism includes Toluene storage tank, which is connected to a recovery pipe and equipped with corresponding valves; The wastewater storage tank is connected to a distributor via a discharge pipe with a regulating valve, and is also connected to a vacuum condenser and an external drain pipe.

2. The apparatus for recovering hydrazine hydrate according to claim 1, characterized in that: The toluene storage tank is connected to the distillation column via a recovery pump; The separator is equipped with an interface gauge, which is electrically connected to the regulating valve.

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