Phosphine gas washing and drying device
By combining a washing unit and a drying unit, a specific detergent is used to remove entrained substances and moisture from phosphine gas, solving the problem of difficult removal of yellow phosphorus and large particulate matter in the prior art, and achieving efficient operation and cost reduction of the device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUBEI SINOPHORUS ELECTRONIC MATERIALS CO LTD
- Filing Date
- 2025-07-22
- Publication Date
- 2026-06-19
AI Technical Summary
In existing phosphine production processes, it is difficult to effectively remove entrained yellow phosphorus, phosphine, and large particulate matter, leading to equipment damage and increased costs.
The device includes a washing unit, a detergent reflux unit, and a phosphine drying unit. Through a system consisting of a washing tower, a circulating pump, a cooler, an evaporator, and a regeneration tower, detergents such as NaOH and CS2 are used, combined with a dehydration tower to remove entrained substances and moisture from the phosphine.
It effectively removes yellow phosphorus, biphosphine, and large particulate matter from phosphine gas, reduces detergent consumption, and lowers equipment damage and production costs.
Smart Images
Figure CN224371028U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of gaseous detergent drying, and in particular to a method and apparatus for washing and drying phosphine gas. Background Technology
[0002] Phosphine, an inorganic compound with the chemical formula PH3, is a colorless, highly toxic, and flammable liquefied compressed gas stored in steel cylinders. As a crucial electronic gas in semiconductor manufacturing processes, phosphine is one of the most technologically demanding electronic-grade specialty gases, primarily used in processes such as ion implantation and doping. Phosphine production mainly involves two methods. The first method, using yellow phosphorus and caustic soda to produce sodium hypophosphite, yields a large amount of phosphine as a byproduct. This method produces phosphine containing phosphorus sludge and biphosphine. The second method uses zinc phosphide ores and employs acid hydrolysis of zinc phosphide and aluminum phosphide to produce phosphine. This method produces phosphine containing a large amount of particles, as well as brine vapor and sulfuric acid gas. Both methods produce phosphine containing phosphorus sludge, biphosphine, particles, and brine vapor, which are difficult to remove in subsequent processes, damaging equipment and increasing costs. Summary of the Invention
[0003] To solve the above-mentioned technical problems, this utility model provides a method and apparatus for washing and drying phosphine gas, which can effectively remove yellow phosphorus, phosphine and other large particulate matter entrained in phosphine gas, and at the same time remove the moisture entrained in phosphine gas due to washing.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0005] A phosphine gas scrubbing and drying apparatus includes a scrubbing unit A, a detergent return unit B, and a phosphine drying unit C connected in sequence via pipelines.
[0006] Washing unit A includes a washing tower, a circulating pump, and a cooler;
[0007] The detergent reflux unit B includes an evaporator, a detergent regeneration tower, a reflux cooler, and a detergent reflux tank;
[0008] Phosphine drying unit C includes a dehydration tower;
[0009] The bottom of washing unit A is connected to detergent return unit B via pipeline, and the top of washing unit A is connected to phosphine drying unit C via pipeline. Phosphine drying unit C is directly connected to the next process section via pipeline.
[0010] The washing unit A, detergent return unit B, and phosphine drying unit C are connected sequentially via pipelines. Washing unit A and detergent return unit B work together to effectively remove yellow phosphorus, phosphine, and other large particulate matter entrained in phosphine gas. They are also compatible with different detergents and can recover and return the detergents, reducing detergent consumption. The phosphine drying unit C can operate in conjunction with washing unit A and detergent return unit B, or it can operate independently.
[0011] The washing unit A consists of a primary washing tower, a primary circulating pump, a primary cooler, a secondary washing tower, a secondary circulating pump, and a secondary cooler;
[0012] A primary scrubbing tower, a primary circulating pump, and a primary cooler are connected by pipelines to form a primary scrubbing unit.
[0013] The secondary scrubbing tower, secondary circulation pump, and secondary cooler are connected by pipelines to form a secondary scrubbing device;
[0014] The primary and secondary washing units are connected by pipelines.
[0015] The washing unit A delivers phosphine through pipelines and replenishes detergent to the primary washing unit and the secondary washing unit through pipelines respectively.
[0016] The primary washing unit is equipped with a nitrogen pipeline and an exhaust gas pipeline; the secondary washing unit is equipped with a nitrogen pipeline and an exhaust gas pipeline.
[0017] The detergent recirculation unit B consists of an evaporator, a stirring pump, and a detergent regeneration tower connected by pipelines to form a detergent regeneration device.
[0018] The reflux cooler, detergent reflux tank, and reflux pump are connected by pipelines to form a detergent reflux device.
[0019] The detergent regeneration unit and the detergent return unit are connected by pipelines;
[0020] The detergent regeneration device is equipped with a nitrogen pipeline and an exhaust gas pipeline, and the detergent return device is also equipped with a nitrogen pipeline and an exhaust gas pipeline.
[0021] The detergent return device is connected to the washing unit A via pipeline to form a detergent return flow, and then the returned detergent is transported to the primary washing unit and the secondary washing unit via pipeline.
[0022] The bottom of the phosphine drying unit C is also directly connected to the main phosphine gas pipeline via a pipeline, and connected to the washing unit A via a pipeline.
[0023] The phosphine drying unit C includes a primary dehydration tower and a secondary dehydration tower; the primary and secondary dehydration towers are connected by pipelines.
[0024] After washing, the main pipeline is equipped with a filter (3-micron accuracy) and a differential pressure gauge. The differential pressure is observed after the washed gas passes through the filter.
[0025] With a pressure difference of 0~10kPa, the washing effect is good, and it can be directly introduced into the adsorption unit;
[0026] With a pressure difference of 10~100kPa, the detergent effect is poor, but it can be washed by LX1-1 circulation;
[0027] If the pressure difference is greater than or equal to 100 kPa, the detergent needs to be regenerated or replaced.
[0028] In the device of this utility model, it is understood that the connection relationship may selectively include switching valves, pumps, pressure gauges, thermometers, and pH meters, depending on the needs of the equipment.
[0029] This utility model also provides a phosphine gas washing and drying process, which uses the aforementioned apparatus to perform the following steps:
[0030] S1. Detergent is delivered to the washing tower via pipeline, circulates to form a spray, and the cooler is started to control the temperature.
[0031] S2, phosphine gas is sent to the scrubbing tower via pipeline, and after being sprayed and scrubbed, it is sent to the phosphine drying unit C, where it is dried and dehydrated to obtain phosphine gas;
[0032] S3. After the detergent in the washing tower has been used for a period of time, it is sent to the detergent regeneration tower for activation and condensation, and then sent to the detergent return tank, and then pumped back into the washing tower for recycling.
[0033] The physicochemical properties of the phosphine described in this invention are as follows: the main components are phosphine, yellow phosphorus, biphosphine, nitrogen, water, hydrogen, arsine, carbon dioxide, hydrogen sulfide, oxygen / argon, acetylene, ethylene, etc., of which the phosphine content is about 38%, the hydrogen content is about 40%, and the nitrogen content is about 10%; the remainder is mainly yellow phosphorus, biphosphine, arsenides and other impurities.
[0034] As will be understood by those skilled in the art, pretreatment of the equipment for leaks, airtightness, and atmosphere is performed before washing. This specifically includes the following steps: After the entire device is installed, nitrogen is introduced into the system through the main nitrogen line for pressure testing and leak detection to ensure good airtightness. Subsequently, nitrogen is discharged into the exhaust gas treatment system through the exhaust gas line, and the process of repeatedly filling and purging with nitrogen continues until all residual gas in the system is completely replaced.
[0035] Detergents include NaOH, CS2, and carbon tetrachloride at a mass concentration of 1-10%.
[0036] The phosphine gas flow rate is approximately 10~15 kg / h; the detergent circulating spray flow rate is 5~10 m³ / h. There is no specific ratio between the two. An increase in the phosphine flow rate means that the diameter of the scrubbing tower increases, and the detergent flow rate increases.
[0037] In some preferred embodiments, in step S1, after pressure testing, leak testing, and purging, the detergent is piped into the system and then fed into the primary and secondary scrubbing towers. The pumps are then started, and the detergent is delivered to the top of the scrubbing towers to form a spray. Finally, the primary and secondary coolers are started.
[0038] In some preferred embodiments, in step S2, phosphine gas is piped into a primary scrubbing tower, then into a secondary scrubbing tower, and subsequently piped into the phosphine drying unit C. Phosphine gas is piped into a primary dehydration tower, then into a secondary dehydration tower. After two stages of drying and adsorption, the phosphine gas is piped into the next process stage.
[0039] In some preferred cases, after a period of use, the detergent concentration in the washing liquid at the bottom of the primary and secondary washing towers becomes low or ineffective. At this time, the washing liquid can be sent to the detergent reflux unit B for regeneration and reflux through pipeline.
[0040] If the pressure difference is greater than or equal to 100 kPa, the detergent needs to be regenerated or replaced.
[0041] Detergent with reduced concentration or that has become ineffective is gradually fed into the evaporator. When the liquid level in the evaporator reaches about 60-70%, the stirring pump is started, and steam is used to heat the evaporator at the same time.
[0042] The washing liquid is vaporized in the evaporator and enters the detergent regeneration tower, then enters the reflux cooler, and after condensation, it is stored in the detergent reflux tank. The remaining non-condensable gas can be discharged through the pipeline.
[0043] The packing is similar to the structured packing of a distillation column. Considering its corrosiveness, PTFE material can be used.
[0044] When the detergent return tank reaches a level of 70-80% or higher, start the return pump to deliver the returned detergent to the primary and secondary washing units through pipelines for recycling.
[0045] The detergent in the detergent return tank is reused back into the washing tower at a volume fraction of 50-100%.
[0046] When the detergent is being regenerated, if there is insufficient detergent in the primary and secondary scrubbing towers for circulating spraying, fresh detergent should be added.
[0047] In some preferred embodiments, when the adsorbent in the primary and secondary dehydration towers is saturated, steam is used to heat the primary and secondary dehydration towers, and nitrogen is continuously supplied to the primary and secondary dehydration towers through pipelines, and finally discharged through pipelines.
[0048] Under the pipeline conditions of this application, if the phosphine gas, after testing, does not require drying and dehydration, it can directly enter the next process section through pipeline L3-2; if the phosphine gas does not require washing, it can directly enter the phosphine drying unit C through L1-1, and enter the next process section after drying and dehydration.
[0049] When the detergent is regenerated and returned to System A, the liquid level in the bottom of the spray tower of System A can be maintained at 70%~80%.
[0050] This utility model provides a method and apparatus for washing and drying phosphine gas. By setting up a washing unit A, a detergent return unit B, a phosphine drying unit C, and supporting utilities, it can be used with different detergents and complete the recovery and return of detergents, reducing detergent consumption. It can effectively remove yellow phosphorus, phosphine and other large particles entrained in phosphine gas, and at the same time remove the moisture entrained in the phosphine gas due to washing. Attached Figure Description
[0051] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0052] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0053] In the diagram: Washing unit A includes a primary washing tower T1001, a primary circulation pump P1001, a primary cooler E1001, a secondary washing tower T2001, a secondary circulation pump P2001, and a secondary cooler E2001; Detergent reflux unit B includes an evaporator V1001, a stirring pump M1001, a detergent regeneration tower T3001, a reflux cooler E3001, a detergent reflux tank V2001, and a reflux pump P3001; Phosphine drying unit C includes a primary dehydration tower T4001 and a secondary dehydration tower T5001. Utilities include nitrogen (LN), tail gas, and vacuum (LZ). Detailed Implementation
[0054] Example 1
[0055] like Figure 1 As shown, a phosphine gas scrubbing and drying device includes a scrubbing unit A, a detergent return unit B, a phosphine drying unit C, and supporting utilities connected in sequence via pipelines.
[0056] In a preferred embodiment, the washing unit A includes a primary washing tower T1001, a primary circulation pump P1001, a primary cooler E1001, a secondary washing tower T2001, a secondary circulation pump P2001, and a secondary cooler E2001. The primary washing tower T1001, the primary circulation pump P1001, and the primary cooler E1001 are connected by pipeline LX1-1 to form a primary washing device. The secondary washing tower T2001, the secondary circulation pump P2001, and the secondary cooler E2001 are connected by pipeline LX2-1 to form a secondary washing device. The primary washing device and the secondary washing device are connected by pipeline L2.
[0057] In a preferred embodiment, the washing unit A supplies phosphine via pipeline L1 and replenishes detergent to the primary and secondary washing units via pipelines LX, LX-1, and LX-2, respectively. The primary washing unit is equipped with a nitrogen pipeline LN1 and an exhaust gas pipeline LZ1; the secondary washing unit is equipped with a nitrogen pipeline LN2 and an exhaust gas pipeline LZ2; LN1 and LN2 are connected to the main nitrogen pipeline LN, and LZ1 and LZ2 are connected to the main exhaust gas pipeline LZ.
[0058] The primary and secondary washing devices in washing unit A are connected to pipeline LX3 via pipelines LX3-1 and LX3-2, respectively. They are also connected to detergent return unit B via pipeline LX3, and to phosphine drying unit C via pipelines L3 and L3-1. Alternatively, they can be directly connected to the next process section via pipeline L3-2.
[0059] The detergent reflux unit B includes an evaporator V1001, a stirring pump M1001, a detergent regeneration tower T3001, a reflux cooler E3001, a detergent reflux tank V2001, and a reflux pump P3001. The evaporator V1001, stirring pump M1001, and detergent regeneration tower T3001 are connected by pipelines to form a detergent regeneration device. The reflux cooler E3001, detergent reflux tank V2001, and reflux pump P3001 are connected by pipelines to form a detergent reflux device. The detergent regeneration device and the detergent reflux device are connected by pipeline LX4. The detergent regeneration device is equipped with a nitrogen pipeline LN3 and a tail gas pipeline LZ3. The detergent reflux device is equipped with a nitrogen pipeline LN4 and a tail gas pipeline LZ4. Pipelines LN3 and LN4 are connected to the main nitrogen pipeline LN, and pipelines LZ3 and LZ4 are connected to the main tail gas pipeline LZ.
[0060] The detergent return device is connected to the washing unit A via pipeline LX5 to form a detergent return flow. The returned detergent is then transported to the primary washing unit and the secondary washing unit via pipelines LX5-1 and LX5-2, respectively.
[0061] The phosphine drying unit C includes a primary dehydration tower T4001 and a secondary dehydration tower T5001. The primary and secondary dehydration towers T4001 are connected via pipeline L4. The phosphine drying unit C is connected to the next process section via pipelines L5 and L6, directly connected to the main phosphine gas pipeline L via pipeline L1-1, and connected to the washing unit A via pipelines L3 and L3-1.
[0062] The phosphine drying unit C is filled with a regenerable, highly efficient moisture adsorbent. The adsorbent can be activated by heating the primary dehydration tower T4001 and the secondary dehydration tower T5001 with steam.
Claims
1. A phosphine gas scrubbing and drying apparatus, characterized in that, This includes sequentially connecting the washing unit A, the detergent return unit B, and the phosphine drying unit C via pipelines; Washing unit A includes a washing tower, a circulating pump, and a cooler; The detergent reflux unit B includes an evaporator, a detergent regeneration tower, a reflux cooler, and a detergent reflux tank; Phosphine drying unit C includes a dehydration tower; The bottom of washing unit A is connected to detergent return unit B via pipeline, and the top of washing unit A is connected to phosphine drying unit C via pipeline. Phosphine drying unit C is directly connected to the next process section via pipeline.
2. The phosphine gas scrubbing and drying apparatus according to claim 1, characterized in that, The washing unit A consists of a primary washing tower (T1001), a primary circulating pump (P1001), a primary cooler (E1001), a secondary washing tower (T2001), a secondary circulating pump (P2001), and a secondary cooler (E2001); The primary washing tower (T1001), primary circulating pump (P1001), and primary cooler (E1001) are connected by pipelines to form a primary washing unit. The secondary scrubbing tower (T2001), the secondary circulating pump (P2001), and the secondary cooler (E2001) are connected by pipelines to form a secondary scrubbing device; The primary and secondary washing units are connected by pipelines.
3. The phosphine gas scrubbing and drying apparatus according to claim 1, characterized in that, The washing unit A delivers phosphine through pipelines and replenishes detergent to the primary washing unit and the secondary washing unit through pipelines respectively. The primary scrubbing unit is equipped with a nitrogen pipeline and an exhaust gas pipeline; The secondary scrubbing unit is equipped with a nitrogen pipeline and an exhaust gas pipeline.
4. The phosphine gas scrubbing and drying apparatus according to claim 1, characterized in that, The detergent recirculation unit B consists of an evaporator (V1001), a stirring pump (M1001), and a detergent regeneration tower (T3001) connected by pipelines to form a detergent regeneration device. The reflux cooler (E3001), detergent reflux tank (V2001), and reflux pump (P3001) are connected by pipelines to form a detergent reflux device; The detergent regeneration unit and the detergent return unit are connected by pipelines; The detergent regeneration device is equipped with a nitrogen pipeline and an exhaust gas pipeline, and the detergent return device is also equipped with a nitrogen pipeline and an exhaust gas pipeline.
5. The phosphine gas scrubbing and drying apparatus according to claim 4, characterized in that, The detergent return device is connected to the washing unit A via pipeline to form a detergent return flow, and then the returned detergent is transported to the primary washing unit and the secondary washing unit via pipeline.
6. The phosphine gas scrubbing and drying apparatus according to claim 4, characterized in that, The bottom of the phosphine drying unit C is also directly connected to the main phosphine gas pipeline via a pipeline, and connected to the washing unit A via a pipeline.
7. The phosphine gas scrubbing and drying apparatus according to claim 4, characterized in that, The phosphine drying unit C includes a primary dehydration tower (T4001) and a secondary dehydration tower (T5001); the primary dehydration tower (T4001) and the secondary dehydration tower (T5001) are connected by pipelines.