Range of limitations on material transfer flow rate under different conditions
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Dear experts: Regarding the issue of transfer speeds for flammable and explosive materials in chemical engineering design, domestic regulations such as GB13348-92, the Static Electricity Safety Regulations for Liquid Petroleum Products, provide guidelines on this matter； The GB12158 General Guidelines for Preventing Static Electricity Accidents contain some relatively rough provisions on this matter. For very specific situations like the one below, the flow velocity limit values should vary; everyone is encouraged to actively discuss the specific figures. 1) Speed limits for the flow of conductive fluids in conductive pipes 2) Speed limits for the flow of conductive fluids in non-conductive pipes 3) Speed limits for the flow of non-conductive fluids in conductive pipes 4) Speed limits for the flow of non-conductive fluids in non-conductive pipes
The consideration of flow rate generally refers to economy and safety. The process design manual specifies the flow rate range for each medium; as long as the value falls within that range during design, it is acceptable. In my opinion, the various scenarios outlined above are meaningless; it is necessary to discuss things in terms of the transmission conditions specific to each medium.
Reply to 2# Yunfan Fengying: The flow rate required by process specifications is generally determined with considerations for economy and safety; for flammable and explosive materials, the electrical engineering department is responsible for carrying out anti-static design.
Reply to 2# Yunfan Fengying: Generally speaking, the risk of static electricity varies in the different situations mentioned above. This risk can usually be reduced by measures such as limiting the flow rate; if it’s not possible to limit the flow rate, then it becomes necessary to consider installing static electricity eliminators. When conducting a detailed assessment of the static electricity risk level during transmission, it is generally necessary to determine whether the transmission medium is conductive and whether the transmission pipes are conductive; different situations require different maximum flow rates. Although many standards specify the maximum allowable flow rate under different conditions, they also state that if the transmission medium is non-conductive, the risk of the transmission pipes becoming non-conductive increases; in such cases, measures such as bonding and grounding may be ineffective, making it even more important to keep the flow rate within safe limits. However, no distinction is made between the flow rates under these different conditions; the commonly recommended flow rates are based on economic considerations, which is why this thread was created to allow sailors to discuss the matter