Ventilation design and exhaust gas treatment for hazardous waste storage areas
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I would like to ask: the regulations specify that accident ventilation for hazardous waste storage areas should be 12 times per hour, but what about normal ventilation? Hazardous waste warehouses are different from Class A warehouses. First, it must be airtight; natural ventilation is not allowed ； Second, exhaust gas needs to be collected and treated. Previously, we designed for 1-2 normal ventilation cycles, but this was rejected by experts in the safety report, and the design was adjusted to 6 cycles per hour. Finally, the fan in this warehouse is designed to handle a flow rate of 8,000 m3/h, with the gas being sent to an RTO for combustion. The RTO is quite large, and rotary adsorption units are not used, which is a waste. Now, another hazardous waste storage facility has been encountered; in accordance with Article 6.2.2 of GB18597-2001 \"Standards for Pollution Control of Hazardous Waste Storage\", a liquid leakage collection system, gas exhaust outlets, and gas purification equipment are required. Activated carbon adsorption treatment is proposed. There is an issue related to this: according to the HJ2026-2013 \"Technical Specifications for the Treatment of Industrial Organic Waste Gases by Adsorption\", the concentration of gases entering the activated carbon adsorption unit should be 25% below the lower explosive limit. Additionally, due to the strict sealing measures in place for managing hazardous waste storage areas, the VOC concentrations in such areas are usually lower than the levels permitted by environmental regulations. This is quite awkward; with normal ventilation, when the concentration is below the environmental emission limits, no treatment is necessary. Emergency ventilation: if the explosive lower limit is reached and there is no way to use activated carbon for absorption, then there is no way to handle the situation. Is there any good method? ?
1. Even when the emission concentration is low, environmental protection equipment is still necessary; its efficiency should be over 90%. 2. Even under emergency ventilation conditions, it is not possible to reach the lower explosion limit, so the air flow rate can be increased
I don’t know where to start with the design.
This post was last edited by Liao Design_QL55o on 2023-8-10 at 18:41, as follows:
This problem is easy to solve: use ventilation ducts for normal air flow and then a exhaust gas treatment system. Emergency ventilation uses wall-mounted axial flow fans or rooftop fans. Reason: Proper ventilation requires exhaust gas treatment to meet the requirements of environmental inspection agencies. Emergency ventilation is used to prevent explosions, choosing the lesser of two evils. There is no need for an exhaust treatment device. Key point: The air volume for emergency ventilation is ensured by both the ventilation through the ducts and the ventilation provided by the supplementary axial flow fans. In the event of an accident, the ventilation of the air ducts can be shut down in a sequential manner, while the axial flow fans that do not have air ducts can be activated sequentially. In this way, it is impossible for the concentration inside the air ducts to reach 25% of the explosive lower limit.