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You work at a major production facility, and operate a batch reactor running a binary reaction. The reactor has been charged with the limiting reactant. Describe at least one aspect of the process which you should verify prior to initiating the reaction, and the possible consequences of a failure to perform this verification. Your response should comprise 3-4 sentences.
Check that the temperature control systems are functioning properly. The reaction rate in a batch reactor is controlled by the temperature.
- Check that the reactor has not been overcharged with any of the reactants by checking the level in the tank. Otherwise, the excess heat generated (if the reaction is exothermic) or consumed (if the reaction is endothermic) may alter the system temperature undesirably.
- Check that the temperature of both reactants is at the correct starting temperature.
Failure to verify any of these conditions prior to running the reaction may lead to thermal runaway, possibly triggering an explosion and possible fires, and yielding injuries, casualties, and/or damage to facility infrastructure, nearby communities, nearby businesses, and the environment.
Suppose you are an operator at a tank farm. You intend to deliver hydrochloric acid from a tanker to an appropriate storage tank through a hose. You are aware that the facility contains a tank for storing sodium hypochlorite, which liberates chlorine gas upon combination with acids. Describe at least two aspects of the feeding operation which should be verified prior to delivery.
- Operators should ensure that the contents in the tank are, in fact, hydrochloric acid. This can be verified with lab testing at the facility.
- Before running the acid through the hose, you should check that the hose is connected to the correct tank. (In particular, you should ensure the acid hose is not connected to the sodium hypochlorite tank prior to attempting delivery, in order to prevent chlorine liberation!)
- Check that the hose is intact, so that no acid will leak from the hose or that the hose will not rupture, spewing the acid.
Suppose you operate a tanker truck for conveying DME from a storage facility to a factory. DME is known to be a dangerously flammable substance. Outline measures you should take to verify safe operation of the truck and delivery of DME to the factory and the importance of verifying before acting to catastrophic incident prevention. Be sure to consider the tanker specifications.
Ensure that trucks are pressure tested, leak tested, and visually inspected for cracks. If necessary, ensure the tanker is equipped with a suitable lining. Verify that the storage capacity of the tanker is listed, matches the actual storage capacity, and that the tanker is filled to a level beneath the actual capacity. Verification protocols are important for ensuring the tanker has not been overfilled or prone to rupture and/or release of flammable substances, such as DME. If the tanker is overfilled, then the pressure of its contents may increase beyond that which the tanker can withstand, rupturing the tank and triggering a deadly explosion of flammable DME vapor. Such a calamity could also incur significant infrastructural and environmental damage.