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CN-122006399-A - Synthesis gas H2Continuous regulation and control process for proportion of CO

CN122006399ACN 122006399 ACN122006399 ACN 122006399ACN-122006399-A

Abstract

The invention belongs to the technical field of synthesis gas treatment, and provides a continuous regulation and control process for the proportion of H 2 /CO of synthesis gas. The process comprises the steps of introducing mixed gas into a first adsorption tower, selectively adsorbing H 2 ,CO 2 and CO as tail gas, discharging the tail gas discharged from the first adsorption tower into a second adsorption tower, selectively adsorbing CO by the second adsorption tower, carrying out subsequent treatment on the residual CO 2 as tail gas, carrying out desorption treatment on the first adsorption tower to obtain H 2 , carrying out desorption treatment on the second adsorption tower to obtain CO, and respectively recovering the first adsorption tower and the second adsorption tower to corresponding adsorption conditions after the desorption is completed, and then carrying out the next round of adsorption-desorption circulation. The process can realize high-efficiency separation of H 2 and CO, continuously and stably regulate and control the H 2 /CO ratio, and the adsorbent has excellent performance.

Inventors

  • JING JIEYING
  • YANG JIAWEI
  • GU CHENG
  • LI WENYING

Assignees

  • 太原理工大学

Dates

Publication Date
20260512
Application Date
20260209

Claims (10)

  1. 1. A process for continuously regulating and controlling the proportion of H 2 /CO in synthesis gas is characterized by comprising the following steps: 1) Introducing the mixed gas into a first adsorption tower, and discharging the first adsorbent which selectively adsorbs H 2 ,CO 2 and CO as tail gas out of the first adsorption tower; 2) Introducing the tail gas discharged from the first adsorption tower into a second adsorption tower, selectively adsorbing CO by the second adsorbent, and taking the residual CO 2 as the tail gas for subsequent treatment; 3) Carrying out desorption treatment on the first adsorption tower to obtain H 2 ; 4) Carrying out desorption treatment on the second adsorption tower to obtain CO; 5) After the desorption is completed, the first adsorption tower and the second adsorption tower are respectively restored to the corresponding adsorption conditions, and the next round of adsorption-desorption cycle is carried out; The first adsorbent is filled in the first adsorption tower, and the second adsorbent is filled in the second adsorption tower.
  2. 2. The process for continuously regulating the ratio of H 2 to CO as claimed in claim 1 wherein the mixture comprises H 2 , CO and CO 2 .
  3. 3. The process for continuously regulating the ratio of H 2 to CO as claimed in claim 1, wherein the process for preparing the first adsorbent comprises the steps of: A. placing the activated carbon in a nitric acid solution, and sequentially carrying out reflux treatment and drying to obtain modified activated carbon; B. Mixing a palladium source, a copper source, modified activated carbon, an auxiliary agent and water, and then adding a binder to obtain strip-shaped particles; C. and drying, calcining and reducing the strip-shaped particles in sequence to obtain the first adsorbent.
  4. 4. The continuous regulation and control process for the proportion of the synthesis gas H 2 /CO according to claim 3, wherein in the step A, the concentration of the nitric acid solution is 5-10wt%, the temperature of the reflux treatment is 80-90 ℃, the time of the reflux treatment is 2-4 hours, the temperature of the drying is 110-120 ℃, and the time of the drying is 8-12 hours; In the step B, the palladium source is PdCl 2 , the copper source is Cu (NO 3 ) 2 ·3H 2 O, the auxiliary agent is CeO 2 , the binder is alumina sol, the palladium source and the copper source are recorded as active components, the molar ratio of the palladium source to the copper source is 1:2-4, the mass ratio of the modified active carbon to the active components to the auxiliary agent to the binder is 50-70:20-35:3-8:2-5, the mixing comprises ultrasonic mixing and stirring mixing, the ultrasonic mixing time is 30-60 min, the stirring mixing temperature is 60-80 ℃, the stirring mixing time is 8-12 h, and the diameter of the strip-shaped particles is 2-4 mm.
  5. 5. The continuous regulation and control process for the ratio of the synthesis gas H 2 /CO according to claim 3 or 4, wherein in the step C, the drying temperature is 110-120 ℃, the drying time is 4-6 hours, the calcining is performed in an inert atmosphere, the calcining temperature is 350-450 ℃, the calcining time is 2-3 hours, the reducing is performed in a hydrogen atmosphere, the reducing temperature is 200-250 ℃, and the reducing time is 1-2 hours.
  6. 6. The process for continuously regulating the ratio of H 2 to CO as claimed in claim 1, wherein the process for preparing the second adsorbent comprises the steps of: a. Mixing the pretreated molecular sieve, a nickel source, an iron source, an auxiliary agent and an ethanol water solution, and adding a binder to obtain spherical particles; b. And drying, calcining and reducing the spherical particles in sequence to obtain the second adsorbent.
  7. 7. The continuous control process for the proportion of the synthesis gas H 2 /CO according to claim 6, wherein in the step a, the pretreatment is roasting treatment, the roasting treatment temperature is 550-600 ℃, the roasting treatment time is 2-3H, the molecular sieve is ZSM-5 molecular sieve, the nickel source is Ni (NO 3 ) 2 ·6H 2 O, the iron source is Fe (NO 3 ) 3 ·9H 2 O, the auxiliary agent is ZrO 2 ), the binder is silica sol, the volume ratio of the ethanol aqueous solution is 1:1, the nickel source and the iron source are marked as active components, the molar ratio of the nickel source to the iron source is 3-5:1, the mass ratio of the pretreated molecular sieve, the active components, the auxiliary agent and the binder is 45-65:25-40:5-10:3-6, the mixing temperature is 50-60 ℃, the mixing time is 6-10H, and the particle size of spherical particles is 100-200 mu m.
  8. 8. The continuous regulation and control process for the ratio of the synthesis gas H 2 /CO according to claim 6 or 7, wherein in the step b, the drying temperature is 100-110 ℃, the drying time is 6-8 hours, the calcining temperature is 400-500 ℃, the calcining time is 3-4 hours, the reducing atmosphere is hydrogen-nitrogen mixed gas, the volume ratio of the hydrogen to the nitrogen is 10-20:80-90, the reducing temperature is 300-350 ℃, and the reducing time is 2-3 hours.
  9. 9. The continuous regulation and control process for the proportion of the synthesis gas H 2 /CO according to claim 1, wherein in the step 1), the adsorption temperature is 25-50 ℃, the adsorption pressure is 0.5-1.5 MPa, and the airspeed of the mixed gas is 500-1000H -1 ; In the step 3), the temperature of the desorption treatment is 80-120 ℃, and the pressure of the desorption treatment is 0.05-0.1 MPa.
  10. 10. The continuous regulation and control process for the proportion of the synthesis gas H 2 /CO according to claim 1 or 9, wherein in the step 2), the adsorption temperature is 30-60 ℃, the adsorption pressure is 0.3-1 MPa, and the space velocity of the tail gas discharged from the first adsorption tower is 800-1500H -1 ; In the step 4), the temperature of desorption treatment is 150-200 ℃, and when the temperature rises to the desorption treatment temperature, nitrogen is introduced to purge, and the space velocity of the nitrogen is 300-500 h -1 .

Description

Continuous regulation and control process for H 2/CO ratio of synthesis gas Technical Field The invention relates to the technical field of synthesis gas treatment, in particular to a continuous regulation and control process for the proportion of H 2/CO of synthesis gas. Background The synthesis gas (the main components are H 2 and CO) is an important chemical raw material and is widely applied to a plurality of chemical processes such as methanol synthesis, fischer-Tropsch synthesis, ammonia synthesis and the like. The different chemical reactions have significant differences in the H 2/CO ratio requirements in the synthesis gas, for example, the H 2/CO ratio required for methanol synthesis is about 2:1, and the H 2/CO ratio required for Fischer-Tropsch synthesis is adjusted between 1:1 and 2:1. Therefore, the accurate and continuous regulation and control of the proportion of H 2/CO in the synthesis gas is realized, and the method is a key premise for guaranteeing the efficient and stable operation of the subsequent chemical process. At present, the technology for regulating and controlling the H 2/CO ratio of the synthesis gas mainly comprises a shift reaction method, a membrane separation method, an adsorption separation method and the like. The conversion reaction method adjusts the content ratio of H 2 and CO through the conversion reaction of CO and water, but the method has the characteristics of harsh reaction conditions, difficult realization of wide-range accurate regulation and control, high separation efficiency, low energy consumption and the like, but the membrane material has high cost, membrane pollution is easy to occur during long-term operation, the separation effect is influenced, and the adsorption separation method realizes separation based on the adsorption performance difference of different gas components on the adsorbent, has the characteristics of simple operation, flexible regulation and control and the like, and becomes a research hot point for the separation and proportion regulation and control of the synthesis gas. The existing adsorption separation technology mostly adopts a single adsorbent or a single-stage adsorption process, so that the high-efficiency separation and recovery of H 2 and CO are difficult to realize simultaneously, and the problems that the H 2/CO proportion regulation and control precision is low, continuous operation is impossible and the like exist. In addition, the selective adsorption performance of the existing adsorbent on H 2 or CO needs to be improved, so that the purity of the separated product gas is insufficient, and the subsequent application is influenced. Therefore, the research results in a continuous regulation process which can realize the efficient separation of H 2 and CO, continuously and stably regulate and control the H 2/CO ratio and has excellent adsorbent performance, and has important industrial application value. Disclosure of Invention The invention aims to provide a continuous regulation and control process for the proportion of H 2/CO in synthetic gas, which solves the problems that the prior art has low regulation and control precision of H 2/CO proportion, can not run continuously and has insufficient purity of separated product gas. In order to achieve the above object, the present invention provides the following technical solutions: the invention provides a continuous regulation and control process for the proportion of H 2/CO of synthesis gas, which comprises the following steps: 1) Introducing the mixed gas into a first adsorption tower, and discharging the first adsorbent which selectively adsorbs H 2,CO2 and CO as tail gas out of the first adsorption tower; 2) Introducing the tail gas discharged from the first adsorption tower into a second adsorption tower, selectively adsorbing CO by the second adsorbent, and taking the residual CO 2 as the tail gas for subsequent treatment; 3) Carrying out desorption treatment on the first adsorption tower to obtain H 2; 4) Carrying out desorption treatment on the second adsorption tower to obtain CO; 5) After the desorption is completed, the first adsorption tower and the second adsorption tower are respectively restored to the corresponding adsorption conditions, and the next round of adsorption-desorption cycle is carried out; The first adsorbent is filled in the first adsorption tower, and the second adsorbent is filled in the second adsorption tower. Preferably, the mixed gas comprises H 2, CO and CO 2. Preferably, the preparation method of the first adsorbent comprises the following steps: A. placing the activated carbon in a nitric acid solution, and sequentially carrying out reflux treatment and drying to obtain modified activated carbon; B. Mixing a palladium source, a copper source, modified activated carbon, an auxiliary agent and water, and then adding a binder to obtain strip-shaped particles; C. and drying, calcining and reducing the strip-shaped particles in seque