Improved device for determining non-volatile residue of anhydrous hydrazine based on direct heating evaporation method

Abstract

The utility model discloses an anhydrous hydrazine non-volatile residue determination improvement device based on direct heating evaporation method belongs to analytical technical field, include: inert gas supply unit, heating evaporation unit is equipped with sealed box, heating mechanism, a plurality of evaporation dish for placing sample and located inert gas import and steam export on the sealed box, condensing recovery unit is equipped with condensing box, the condensing tube group of setting in the condensing box, with cooling medium access and cooling medium discharge port of condensing box intercommunication. This anhydrous hydrazine non-volatile residue determination improvement device based on direct heating evaporation method, adopts direct heating method, and the sample is placed in the evaporation dish in the heating box and is evaporated, and a plurality of samples can be made at the same time non-volatile residue, improves the test efficiency, and the inert gas is passed in the test process, can avoid the hydrazine steam under the condition of heating mass gathering and causes the danger and accelerates the evaporation rate.

Description

Technical Field

[0001] This utility model belongs to the field of analytical technology, and in particular relates to an improved device for determining the non-volatile residue of anhydrous hydrazine based on direct heating evaporation method. Background Technology

[0002] Anhydrous hydrazine is highly toxic and volatile, and strict control of its quality indicators is crucial for the efficient operation of engines. Among these indicators, the content of non-volatile residues is a key performance indicator of anhydrous hydrazine, and accurate determination of this content is decisive for assessing its quality. Standards specify the use of the droplet evaporation method to detect the content of non-volatile residues in anhydrous hydrazine. However, with the rapid increase in the use of anhydrous hydrazine, higher demands are placed on detection methods and equipment, and existing dedicated droplet evaporation equipment is no longer sufficient to meet practical needs.

[0003] Currently, the droplet evaporation method requires a complex and cumbersome specialized apparatus. During prolonged testing, it is not only inefficient but also prone to vacuum pump damage due to incomplete condensation and absorption of corrosive gases. These problems severely impact the normal operation of testing, particularly during heavy workloads, significantly hindering the quality control of anhydrous hydrazine. In contrast, industrial hydrated hydrazine and the US standard allow for the determination of non-volatile hydrazine residues using a direct heating method with electric hot plates, which offers advantages in terms of ease of operation and testing efficiency. Therefore, it is necessary to develop a device for determining non-volatile residues of anhydrous hydrazine based on a direct heating evaporation method to address the problems of existing technologies. Utility Model Content

[0004] The purpose of this invention is to solve the problems of cumbersome operation and low detection efficiency in the existing technology, and to propose an improved device for the determination of anhydrous hydrazine non-volatile residues based on direct heating evaporation method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An improved apparatus for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation method, comprising: An inert gas supply unit is used to supply and purify inert gas; The heating and evaporation unit includes a sealed box, a heating mechanism, multiple evaporation dishes for placing samples, and an inert gas inlet and a vapor outlet located on the sealed box. The inert gas inlet is connected to the inert gas supply unit. The condensation recovery unit includes a condensation box, a condensation tube assembly installed inside the condensation box, a cooling medium inlet communicating with the condensation box, and a cooling medium outlet. The input end of the condensation tube assembly is connected to the steam outlet. The inert gas introduced is used to purge the hydrazine vapor generated by evaporation inside the sealed chamber, so that it enters the condensation and recovery unit through the vapor outlet and is condensed and collected.

[0006] Preferably, the front side of the sealed enclosure is provided with a sealing door with a locking mechanism, and the sealed enclosure is provided with an observation window.

[0007] Preferably, the heating mechanism includes a heating plate installed inside a sealed box, and a shelf with multiple heating holes is slidably mounted on the heating plate, with the evaporating dish placed in the heating holes.

[0008] Preferably, the inert gas inlet branches into multiple branches that extend into the sealed housing, each corresponding to a row of heating holes on the heating plate, to achieve zoned purging.

[0009] Preferably, the sealed housing has an installation frame on its side, and the condenser can be slidably installed in the installation frame to form a pull-out housing structure. A magnet is installed inside the installation frame, and an iron block corresponding to the magnet is provided on the side wall of the condenser. The input end of the condenser tube assembly is connected to the steam outlet through a detachable pipe connector.

[0010] Preferably, a heat insulation layer is provided at the connection between the heating evaporation unit and the condensation recovery unit.

[0011] Preferably, the mounting frame is equipped with a position detection switch, which is electrically connected to the heating control circuit of the heating evaporation unit. When the condensation recovery unit is not installed in place, the heating control circuit cannot be started.

[0012] Preferably, the cooling medium inlet and cooling medium outlet are used to connect to an external refrigeration cycle device, and the cooling medium introduced is an aqueous solution of ethylene glycol with a temperature range of 2-10℃, wherein the mass fraction of ethylene glycol is 2% to 20%.

[0013] Preferably, it also includes a waste gas absorption unit, comprising a waste liquid collection bottle and a waste gas absorption bottle connected in sequence. The waste gas absorption bottle contains residual waste gas absorption liquid for absorbing and treating incompletely condensed residual waste gas. The output end of the condenser tube assembly is connected to the input end of the waste liquid collection bottle.

[0014] In summary, the technical effects and advantages of this utility model are as follows: This improved device for determining anhydrous hydrazine non-volatile residues based on direct heating evaporation employs a direct heating method, placing the sample in an evaporating dish within a heating chamber for evaporation. It can simultaneously prepare non-volatile residues from multiple samples. Compared to the traditional droplet evaporation method, it significantly shortens the detection time, improves testing efficiency, and better adapts to the needs of large-scale, long-term testing. It does not require operation under negative pressure, and the device's airtightness does not affect testing efficiency or results. The introduction of inert gas during the testing process avoids the danger of excessive hydrazine vapor accumulation during heating and accelerates the evaporation rate.

[0015] The condensation recovery unit adopts a pull-out box design and is located on the side of the improved device for easy installation and disassembly. The hydrazine vapor outlet is connected to the air inlet of the condensation device through a silicone tube and adapter, which is simple and reliable. In addition, the internal jacket of the condensation recovery unit uses multiple sets of straight condenser tubes to ensure that the hydrazine vapor can be fully condensed, thereby improving the condensation effect. The condensation recovery unit integrates a position detection switch. The position detection switch is triggered only when the condensation recovery unit is installed in place, and the heating control circuit can be started. This avoids safety hazards such as hydrazine vapor leakage caused by the condensation recovery unit not being installed in place, and enhances the safety of the device. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present utility model. Figure 1 ; Figure 2 This is a schematic diagram of the overall structure of the present utility model. Figure 2 ; Figure 3 This is a cross-sectional structural diagram of the present invention; Figure 4 This is a schematic diagram of the structure of the storage rack in this utility model; Figure 5 This is a schematic diagram of the condenser box in this utility model; Figure 6 This is a cross-sectional view of the condensation recovery unit in this utility model; Figure 7 This is a cross-sectional view of the waste gas absorption unit in this utility model.

[0017] In the diagram: 1. Inert gas supply unit; 2. Heating and evaporation unit; 201. Sealed enclosure; 202. Evaporating dish; 203. Inert gas inlet; 204. Steam outlet; 205. Sealed door; 206. Observation window; 207. Heating plate; 208. Heating hole; 209. Shelf; 3. Condensation recovery unit; 301. Condensation box; 302. Condensation tube assembly; 303. Cooling medium inlet; 304. Cooling medium outlet; 305. Mounting frame; 306. Position detection switch; 4. Insulation layer; 5. Waste gas absorption unit; 501. Waste liquid collection bottle; 502. Waste gas absorption bottle. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0019] Reference Figure 1-6 An improved device for determining the non-volatile residues of anhydrous hydrazine based on direct heating evaporation method is disclosed. The device comprises an inert gas supply unit 1, a heating evaporation unit 2, a condensation recovery unit 3, a heat insulation layer 4, and a waste gas absorption unit 5. These units are connected via pipelines and mechanical structures to form a complete detection system. The device adopts a modular design, facilitating operation, maintenance, and functional expansion.

[0020] Inert gas supply unit 1 is used to provide and purify inert gas. Inert gas supply unit 1 includes an inert gas source (such as a nitrogen cylinder) and a gas filter. After purification by the gas filter, the inert gas is transported to the heating and evaporation unit 2 through a polytetrafluoroethylene (PTFE) pipeline to ensure gas purity and avoid the influence of impurities on the detection results. The heating and evaporation unit 2 is the core part of this device, including a sealed box 201, a heating mechanism, multiple evaporation dishes 202, an inert gas inlet 203, and a steam outlet 204.

[0021] Reference Figure 1-2 The sealed enclosure 201 is made of stainless steel. The front side is equipped with a sealing door 205 with a locking mechanism to ensure dust prevention and airtightness. The sealing door 205 is equipped with an observation window 206 to facilitate real-time observation of the heating status inside the enclosure. The side of the enclosure is equipped with an installation frame 305 for installing the condensation recovery unit 3.

[0022] The heating mechanism includes a heating plate 207 installed inside a sealed chamber 201. A shelf 209 is slidably mounted on the heating plate 207. The shelf 209 has multiple heating holes 208 for placing evaporating dishes 202. In this embodiment, the heating holes 208 are arranged in a 3*3 layout. When in use, with the sealed door 205 open, the shelf 209 is pulled outward to facilitate the placement of the evaporating dishes 202. After the evaporating dishes 202 are placed, the shelf 209 is pushed back into the sealed chamber 201. The evaporating dishes 202 are made of glass and have a volume of approximately 120mL, which can hold 80mL of liquid to be evaporated. The heating plate 207 uses an electric heating element, and the heating temperature range is RT~300℃ to meet different testing requirements.

[0023] Reference Figure 1-3 The inert gas inlet 203 branches into multiple channels and extends into the sealed housing 201, corresponding to the multiple rows of heating holes 208 on the heating plate 207, thus achieving zoned purging. The inert gas purges the hydrazine vapor generated by evaporation within the sealed housing 201, preventing the large accumulation of hydrazine vapor from causing danger and accelerating the evaporation process.

[0024] The vapor outlet 204 is located at the top of the sealed housing 201 and is connected to the condensation recovery unit 3, which introduces hydrazine vapor into the condensation recovery unit 3 for condensation and collection.

[0025] Reference Figure 1-6 The condensation recovery unit 3 includes a condensation box 301, a condensation tube assembly 302 disposed in the condensation box 301, a cooling medium inlet 303 communicating with the condensation box 301, and a cooling medium outlet 304. The input end of the condensation tube assembly 302 is connected to the steam outlet 204.

[0026] A mounting frame 305 is provided on the side of the sealed enclosure 201. The condenser box 301 is slidably installed in the mounting frame 305 to form a pull-out enclosure structure. The condenser box 301 is made of stainless steel and is slidably installed in the mounting frame 305 on the side of the sealed enclosure 201 to form a pull-out enclosure structure. Specifically, guide rails are provided on the top and bottom surfaces of the mounting frame 305. The condenser box 301 is slidably positioned between the two guide rails to achieve stable sliding. A magnet is installed on the inside of the mounting frame 305. A corresponding iron block is provided on the side wall of the condenser box 301. After the condenser box 301 is installed in place, the magnet and the iron block attract each other to ensure that the condenser box 301 is installed firmly.

[0027] Reference Figure 1-7The condenser tube assembly 302 is installed inside the condenser box 301. It adopts a multi-set straight condenser tube design to increase the condensation area and ensure that the exhaust gas is fully condensed. The input end of the condenser tube assembly 302 is connected to the steam outlet 204 through a detachable pipe connector for easy disassembly, cleaning and maintenance. The hydrazine vapor evaporates in the sealed box 201, is purged with nitrogen and discharged through the steam outlet 204, and enters the condenser tube assembly 302 for condensation. After condensation, it is introduced into the exhaust gas absorption unit 5 for liquid collection and tail gas treatment.

[0028] The cooling medium inlet 303 and the cooling medium outlet 304 are located on the side of the condenser box 301 and are used to connect to an external refrigeration cycle device. The cooling medium introduced is an ethylene glycol aqueous solution with a temperature range of 2-10℃, wherein the mass fraction of ethylene glycol is 2% to 20% to ensure the condensation effect.

[0029] Reference Figure 6 The mounting frame 305 is equipped with a position detection switch 306, which is electrically connected to the heating control circuit of the heating evaporation unit 2. When the condensation recovery unit 3 is not installed in place, the heating control circuit cannot be started, ensuring operational safety and thus avoiding safety hazards such as hydrazine vapor leakage caused by the condensation recovery unit 3 not being installed in place, thereby enhancing the safety of the device.

[0030] A heat insulation layer 4 is provided at the connection between the heating evaporation unit 2 and the condensation recovery unit 3. The layer is made of ceramic fiber high-efficiency heat insulation material to prevent a large amount of heat energy from being transferred to the condensation recovery unit 3, thereby reducing energy consumption and improving condensation efficiency.

[0031] Reference Figure 6-7 The waste gas absorption unit 5 includes a waste liquid collection bottle 501 and a waste gas absorption bottle 502 connected in sequence. The output end of the condenser tube group 302 is connected to the input end of the waste liquid collection bottle 501. The waste gas absorption bottle 502 is filled with absorbent liquid for absorbing and treating residual waste gas. The waste liquid collection bottle 501 and the waste gas absorption bottle 502 are glass bottles with wooden stoppers. They are connected by a glass tube. The input end extends to the bottom of the bottle, and the output end is located at the wooden stopper at the bottle mouth. The absorbent liquid is a potassium permanganate solution. The condensed hydrazine vapor and nitrogen mixture enters the waste liquid collection bottle 501. The liquefied hydrazine vapor is trapped in the waste liquid collection bottle 501. The nitrogen carries some of the residual gas into the waste gas absorption bottle 502 and is introduced into the potassium permanganate solution to complete the absorption. The potassium permanganate solution becomes ineffective when its color lightens or turns brown and should be replaced in time.

[0032] The working principle of this utility model is as follows: Ensure that all components of the inert gas supply unit 1, heating and evaporation unit 2, condensation and recovery unit 3, insulation layer 4, and waste gas absorption unit 5 are tightly connected without any looseness or leakage.

[0033] When the condenser box 301 is pushed in along the guide rail inside the mounting frame 305, the position detection switch 306 detects that the condensation recovery unit 3 has been installed in place, and the heating control circuit of the heating evaporation unit 2 is in the startable state.

[0034] The heating plate 207 is activated by the heating control circuit. The heating plate 207 uses an electric heating element and the heating temperature range is RT~300℃. The appropriate heating temperature is set according to different detection requirements to heat and evaporate the liquid to be evaporated in the evaporating dish 202.

[0035] The inert gas source is turned on, and the purified inert gas is transported to the heating and evaporation unit 2 through a polytetrafluoroethylene pipeline. The inert gas branches out from the inert gas inlet 203 and extends into the sealed box 201, corresponding to the multiple rows of heating holes 208 on the heating plate 207. This allows for the zonal purging of each area within the sealed box 201, preventing the large accumulation of hydrazine vapor and the resulting danger, and accelerating the evaporation process.

[0036] Hydrazine vapor is purged by inert gas inside the sealed chamber 201 and discharged through the vapor outlet 204 located at the top of the sealed chamber 201. It then enters the condenser tube assembly 302 inside the condenser chamber 301. The condensed hydrazine vapor and nitrogen mixture is connected to the input end of the waste liquid collection bottle 501 of the waste gas absorption unit 5 through the output end of the condenser tube assembly 302.

[0037] The mixed gas entering the waste liquid collection bottle 501 is liquefied hydrazine vapor trapped inside the waste liquid collection bottle 501. Nitrogen carries some of the residual gas through the glass pipe into the waste gas absorption bottle 502. The waste gas absorption bottle 502 is filled with potassium permanganate solution as the absorbent liquid, and the harmful components in the residual gas are absorbed by the potassium permanganate solution.

Claims

1. An improved device for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation, characterized in that, include: An inert gas supply unit (1) is used to supply and purify inert gas; The heating evaporation unit (2) is provided with a sealed box (201), a heating mechanism, multiple evaporation dishes (202) for placing samples, and an inert gas inlet (203) and a vapor outlet (204) located on the sealed box (201). The inert gas inlet (203) is connected to the inert gas supply unit (1). The condensation recovery unit (3) is provided with a condensation box (301), a condensation tube assembly (302) installed in the condensation box (301), a cooling medium inlet (303) connected to the condensation box (301), and a cooling medium outlet (304). The input end of the condensation tube assembly (302) is connected to the steam outlet (204). The inert gas introduced is used to purge the hydrazine vapor generated by evaporation in the sealed housing (201), so that it enters the condensation recovery unit (3) through the vapor outlet (204) and is condensed and collected.

2. The improved apparatus for determining anhydrous hydrazine non-volatile residues based on direct heating evaporation method according to claim 1, characterized in that, The sealed box (201) is provided with a sealing door (205) with a locking mechanism on the front side, and the sealed box (201) is provided with an observation window (206).

3. The improved apparatus for determining anhydrous hydrazine non-volatile residues based on direct heating evaporation method according to claim 1, characterized in that, The heating mechanism includes a heating plate (207) installed in a sealed box (201), a shelf (209) with multiple heating holes (208) is slidably installed on the heating plate (207), and the evaporating dish (202) is placed in the heating holes (208).

4. An improved apparatus for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation method according to claim 3, characterized in that, The inert gas inlet (203) branches out into multiple branches and extends into the sealed housing (201), corresponding to the multiple rows of heating holes (208) on the heating plate (207) to achieve zoned purging.

5. An improved apparatus for determining anhydrous hydrazine non-volatile residues based on direct heating evaporation method according to claim 1, characterized in that, The sealed box (201) has an installation frame (305) on its side. The condenser box (301) is slidably installed in the installation frame (305) to form a pull-out box structure. A magnet is installed inside the installation frame (305). The side wall of the condenser box (301) is provided with an iron block corresponding to the magnet. The input end of the condenser tube assembly (302) is connected to the steam outlet (204) through a detachable pipe connector.

6. An improved apparatus for determining anhydrous hydrazine non-volatile residues based on direct heating evaporation method according to claim 5, characterized in that, A heat insulation layer (4) is provided at the connection between the heating evaporation unit (2) and the condensation recovery unit (3).

7. An improved apparatus for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation method according to claim 5, characterized in that, The mounting frame (305) is provided with a position detection switch (306), which is electrically connected to the heating control circuit of the heating evaporation unit (2). When the condensation recovery unit (3) is not installed in place, the heating control circuit cannot be started.

8. An improved apparatus for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation method according to claim 1, characterized in that, The cooling medium inlet (303) and cooling medium outlet (304) are used to connect to an external refrigeration circulation device. The cooling medium introduced is an aqueous solution of ethylene glycol with a temperature range of 2-10℃, wherein the mass fraction of ethylene glycol is 2% to 20%.

9. An improved apparatus for determining non-volatile residues of anhydrous hydrazine based on direct heating evaporation method according to claim 1, characterized in that, It also includes a waste gas absorption unit (5), which includes a waste liquid collection bottle (501) and a waste gas absorption bottle (502) connected in sequence. The waste gas absorption bottle (502) is filled with residual waste gas absorption liquid that has not been completely condensed. The output end of the condenser tube group (302) is connected to the input end of the waste liquid collection bottle (501).

Images