Analysis of a High-Voltage Room Quasi-Smoke Gas Explosion

Abstract

During an air separation unit shut-down in a methanol production plant, a stop signal was sent to the control cabinet of a synchronous motor for a booster compressor. The control cabinet stopped magnetizing the rotor, while the system logic ensured that the power circuit breakers for the start reactor coils were opened, in order to be ready for the next start-up. Unintentionally, the circuit breaker was still connected (i.e., power was let through the reactors for a prolonged time period), which led to extensive overheating. Subsequently, the central control room received an unaddressed sub-station smoke alarm, and plant operators were sent out to locate the possible source of smoke. The accessible rooms were searched, and traces of smoke were confirmed. The Emergency Response Organization (ERO) was mustered and, through inspection, the Emergency Response Team (ERT) realized that the smoke originated from a ground floor high-voltage room. Fire hoses were arranged for fire extinguishing, and the ERT withdrew to wait for the room to be electrically isolated. About one minute after briefly opening the only set of doors to the high-voltage room, flames were observed, and a quasi-smoke gas explosion violently forced both door blades open and released a substantial fire ball. Personnel had been in the risk zone shortly before the explosion, but luckily no personnel were hit by the slamming door blades or the emerging flames. The incident revealed several learning points related to improper maintenance, ambiguous smoke alarm, lack of flame detectors in the high-voltage room, insufficient risk understanding and training regarding electrically related fire incidents, and the absence of an automatic fire suppression system. In plants processing hydrocarbons, the safety focus regarding hydrocarbon fire and explosion risk is paramount. However, risks related to electrical accidents and compartment fire dynamics (e.g., backdraft and smoke gas explosion) should also be given proper attention.

Analysis of a Costly Fiberglass-Polyester Air Filter Fire

“…There has been much focus on preventing and mitigating fires in hydrocarbon-carrying pipes and equipment, and research on, e.g., active [28,29] and passive [30,31] fire protection of these systems. However, in recent years, several incidents in Norway have struck the utility systems, e.g., a high-voltage room quasi-smoke gas explosion [32] and a major fire in a steam-powered turbine generator [33] as well as the fire analyzed in the present study [4,5]. It may be concluded that the utility systems need more risk attention.…”

Numerical Investigation of the Required Quantity of Inert Gas Agents in Fire Suppression Systems

“…Substituting Equation (12) and Equation 13into Equation 22 (11). Figure 1 shows the quantity of inert gas agents as a function of k. The required inert gas quantity to obtain a design oxygen level per unit enclosure volume decreases with increasing values of k. Therefore, venting out the air-agent mixture not only removes the overpressure effect in an enclosure, it also lowers the mass requirement of inert gas agents.…”

“…Some research [9] has been carried out to investigate the application of inert gas agents in some typical buildings for disabled persons, elderly in nursing homes, and other citizens with reduced cognitive function, etc. Inert gas agents also have great potential as inhibitors of gas explosions by reducing or possibly eliminating the risk of explosions [10][11][12].…”

Universal cyber physical system, a prototype for predictive maintenance

“…In a case study, UniCPS was implemented in a local factory for PdM demonstration. One of the significant parameters is RMS current (Irms), which needs to be closely monitored because fire, explosion, and injury cases are often reported [7] due to the electrical current faults. Therefore, real-time data visualization and anomaly detection is also demonstrated, particularly on electrical RMS current data.…”