How long does it take to replace VOCS activated carbon?

Activated carbon is the most widely used adsorbent, with production and use dating back to the 19th century. Activated carbon is widely used mainly because of its large number of micropores and mesopores and its huge surface area. At present, in the VOCs treatment industry, the activated carbon adsorption process can be said to be the most widely used treatment technology. Many companies face the problem of activated carbon replacement after activated carbon adsorption for a certain period of time. As for how to determine the repla
cement cycle, and how to do the corresponding ledger To avoid penalties, there are certain blind spots.

The pollutant discharge unit shall determine the replacement cycle of activated carbon according to the design plan of the waste gas activated carbon adsorption treatment facility, and fill in the system solid waste pollutant discharge information - application for discharge information module in the "solid waste discharge information table" in the "solid waste discharge information table" in the "Other information". ” Fill in the activated carbon replacement cycle at the corresponding waste activated carbon reporting office, and upload the design plan of the waste gas activated carbon adsorption treatment facility in the attachment. When there is no waste gas treatment facility design plan or the actual construction situation is inconsistent with the design plan, the activated carbon replacement cycle should be calculated according to the following formula, and the calculation process should be uploaded in the attachment. The dynamic adsorption value in the calculation should be higher than 10%. The activated carbon performance certification document on which the adsorption capacity is based.

T=m×s÷(c×10-6×Q×t)

where:

T—replacement cycle, days;

m—the amount of activated carbon, kg;

s—dynamic adsorption capacity, %; (generally 10%)

c—the concentration of VOCs reduced by activated carbon, mg/m3;

Q—air volume, unit m3/h;

t—running time, in h/d.

\Calculation example: In the following table, the last four groups respectively change the amount of activated carbon, the concentration of VOCs reduced by activated carbon, the air volume, and the running time of the first group of data to obtain different replacement cycles.

Calculation case of activated carbon replacement cycle under different conditions

No.	Activated carbon dosage（kg）	Dynamic adsorption capacity（%）	Activated carbon reduces vocs concentration(mg/m³)	Air volume	operation hours（h/d）	time change cycle（天）
1	650	10%	120	250	24	90
2	850	10%	120	250	24	118
3	650	10%	90	250	24	120
4	650	10%	120	350	24	64
5	650	10%	120	250	12	181

1. Environmental management ledger requirements for units involved in activated carbon adsorption of pollutants
According to the requirements in the "Regulations on the Administration of Pollution Discharge Permits", "Notice on Printing and Distributing the "Comprehensive Treatment Plan for Volatile Organic Compounds in Key Industries" (Huanqiqi [2019] No. 53) and the "Practical Manual for the Treatment of Volatile Organic Compounds", pollutant discharge units should establish Environmental management ledger record system, detailed records of adsorbent types and filling conditions, replacement time and amount of one-time adsorbents, regeneration cycle and replacement of regenerative adsorbents, storage and disposal of waste adsorbents, and properly preserved . Environmental management ledger records shall be kept for a period of not less than 5 years.

2. Execution report filing requirements for units involved in activated carbon adsorption of pollutants
When filling in the annual report of the implementation report, the pollutant discharge unit should fill in the information module of the operation of pollution prevention and control facilities - the normal operation of pollution control facilities, and the information about the activated carbon adsorption treatment facilities in the "normal operation of waste gas pollution control facilities". Information on operating costs, removal efficiency and waste activated carbon production.