activated charcoalHow to configure the adsorption box? Direct answer: The three core parameters - the gas flow rate in the adsorption layer is determined according to the form of the adsorbent. The apparent flow rate of granular activated carbon should be controlled at 0.4 to 0.6 meters per second, the thickness of the single layer of carbon should be 400 to 450 millimeters, and the residence time of exhaust gas in the carbon layer should not be less than 0.75 seconds. The supporting requirements also include: filtering the intake first, and controlling the particle concentration at a lower level; The temperature of imported exhaust gas should not be too high, and the relative humidity should be controlled; The box is well sealed, and the multi-layer air distribution structure avoids air flow short circuits. A box with parameters that do not meet the standards, no matter how much charcoal is loaded, it will be in vain.
The flow rate determines the contact time, the thickness of the carbon layer determines the adsorption capacity, and both together determine the penetration period. The flow rate is too fast, and the exhaust gas flashes through the carbon layer, resulting in insufficient adsorption; The carbon layer is too thin, the capacity reserve is insufficient, and penetration arrives early. The dwell time is an indicator that links the two together -0.75 seconds is the lower limit of experience, and devices below this value will speak the detection data. During the design phase, the flow rate is calculated based on the air volume and the cross-section of the charcoal box. Do not rely on adding charcoal for remediation after production.
Half of the lifespan of the charcoal box lies in the intake quality. Particulate matter and oil fumes can clog the charcoal pores, causing a continuous loss of effective adsorption area; Water vapor forms a film on the carbon surface and occupies adsorption sites; High temperature also squeezes the adsorption capacity. So the intake side must be equipped with a filter, and the selection of dust and paint mist should be based on their concentration; Temperature and humidity are controlled according to regulations. Acidic waste gas needs to be washed and pre treated first - not only is the adsorption effect poor, but the corrosion of the equipment body by acidic gases is a real damage.
A few hard requirements in terms of structure: smooth airflow, no short circuits or dead corners - the gaps at the edges of the carbon layer and the gaps between the wall and the carbon layer are all bypass shortcuts, and poor sealing is equivalent to white pumping. The box doors, welds, and pipeline connections are tightly sealed without air leakage, and the bolt connections are firm. The anti-corrosion treatment of the metal shell is in place, and the surface is free of rust and burrs. The multi-layer air distribution structure ensures even distribution of airflow and avoids excessive local flow velocity. The filling should be neat and compact, and the rake should be leveled after filling, without leaving any channels for gully flow. The sealing of manholes and access doors is equally important, and should not be missed during daily inspections.
| parameter | Reference requirements | Verification method | Disposal of non-compliance |
|---|---|---|---|
| Apparent flow velocity | Granular carbon 0.4 to 0.6 meters per second | Air volume divided by cross-section | Change cross-section or adjust air volume |
| Thickness of carbon layer | 400 to 450 millimeters | Actual measurement after loading | Make up the filling amount |
| dwell time | Not less than 0.75 seconds | Accounting and actual measurement | Adjust the level and air volume |
| Intake particulate matter | low concentration | Detect or observe pressure difference | Strengthen preprocessing |
| Box sealing | airtight | Negative pressure test | Repair weld seam door seal |
| Anti corrosion state | rust-free | Visual inspection | Rust removal and anti-corrosion |
Synchronize and keep up with ledger management: record the start and stop time, operating parameters, consumables consumption and replacement records, and energy consumption on a periodic basis. These records are not only operational archives, but also mandatory items for regulatory inspections - boxes with parameters that do not meet the standards are the first to be exposed as records that do not match.
Change the cross-section of the box body - parallel expansion or replacement of large cross-section boxes; Relying on adding more charcoal will only increase resistance and fan power consumption.
Not recommended. The flow rate requirements and loading methods for the two adsorbents are different. Mixing them together can cause uneven airflow and uncontrollable parameters. Therefore, they should be loaded according to the design of a single variety.
During operation, soap solution or portable detector is used to scan welds, door seals, and pipeline interfaces; Perform negative pressure holding test after shutdown, and investigate the pressure drop exceeding the limit section by section.
This article by LuoyangWohong PetrochemicalEquipment Co., Ltd. arranges that the company provides design, manufacturing and operation and maintenance services for condensation recovery, membrane separation recovery and complete solvent recovery devices for chemical and pharmaceutical enterprises. If you need process evaluation or scheme configuration, please contact and exchange.
Mr. Li 13526990215
Hotline
