Carbon Dioxide Recovery System

Ⅰ. Introduction of carbon dioxide recovery device

The CO2 recovery device system consists of units such as defoaming, water washing, storage bag, compression, freeze drying, adsorption drying, refrigeration, storage tank, vaporization, etc. It is used to recover the carbon dioxide produced in the fermentation process and liquefy it for use.

The control system of the device includes display instruments for detection parameters and main operating parameters. The compressor unit and the refrigeration unit are equipped with independent control and fault shutdown systems.

Ⅱ. Configuration scheme of carbon dioxide recovery device

1. Initial purification system: demister, washing tower, circulating water pump, air bag, water seal, pipeline valve, instrument

1-1 demister:

The demister is used to remove the foam from the CO2 raw gas. The foam in the raw gas is removed by the normal pressure water sprayed from the top of the demister, and then the water is discharged to the drain through the sewage device at the bottom. It can be observed through the sight glass installed on the demister.

1-2 washing tower:

The raw gas enters from the bottom of the washing tower, passes through the packing layer, and convects with the washing water to remove alcohol and suspended particles, and the washed water is recycled in the demister.

technical parameter:

1-3 Airbags:

The air bag provides a buffer between the CO2 feed gas and the compressor. The load of the CO2 compressor is controlled by the filling status of the air bag, so the volume of the air bag determines the frequency of the compressor on and off. The airbag material is made of biaxially dipped high-strength membrane material, which has a long service life and an alarm structure for the lower limit of the airbag.

2. Compression system: one compressor                                                                                   

Compression system features: Equipped with a joint venture valve to make the compressor drain automatically, without manual operation, with a high degree of automation. The electric control cabinet has running indication, fault indication and motor overload protection.

3. Purification system: cold dryer, adsorber, dryer, pipeline valve, PLC control

3-1 Cold Dryer:

The CO2 gas temperature from the compressor is cooled to 5°C-10°C again at a temperature of 25°C-60°C, and at the same time, the moisture in the gas is removed and then enters the adsorption drying tower.

Features: a. Improve CO2 gas purity by cooling and draining water.

b. Avoid CO2 condensation in the rear section and ice blockage in the liquid storage system.

c. Fully automatic unmanned operation.

3-2 Adsorption dryer

Double tower type adsorption dryer, each tower is equipped with activated carbon and molecular sieve, the structure of double towers is automatically switched regularly, one tower works, and the other tower is regenerated. The activated carbon in the adsorption drying tower is used to remove the remaining alcohol and odor, and the 3A molecular sieve is used for the gas drying of food-grade CO2. The operation cycle of each tower is about 12 hours.

Features and equipment of purification system: Pneumatic ball valve is used, high degree of automation, and the adsorber + dryer is controlled by PLC.

a. There are two modes of operation: automatic and manual electronic control.

b. Adopt pneumatic valve and SIEMENS S7 programmable control program.

c. Avoid wrong operation. Such as: ice blockage caused by incomplete regeneration of the dryer.

4. Condensation and liquefaction system: refrigerator, CO2 evaporative condenser, pipeline, valve, instrument

4-1 Refrigeration unit, 1 set

Refrigeration compressor type: semi-hermetic piston compressor

The chiller consists of a rack-mounted refrigeration system to liquefy the gas CO2

4-2 CO2 condenser

Features of liquefaction system: 1. The pressure of CO2 system is 1.5-1.8Mpa, which can effectively reduce the solubility of O2 in CO2 liquid and ensure the purity of CO2 liquid. The carbon dioxide yield is also guaranteed.

5. The CO2 evaporative condenser is inclined at 5 degrees, and a timing automatic exhaust device is installed. High-point venting effectively discharges non-condensable gases such as O2 and N2.

6. Liquid storage: CO2 liquid storage tank, pipeline valve, instrument

7. High-efficiency vaporizer system

CO2 vaporizer: It uses steam to heat water, and then baths liquid CO2 with water. The performance is reliable, and the water temperature is controlled by a thermometer. When the water temperature reaches the set value, the steam will automatically stop to work; when the water temperature is lower than the set value, the steam will automatically work;

Control system: 1 compressor cabinet, 1 CO2 cabinet

Ⅲ. CO2 Recovery Unit Recovery System Checklist