Does degassed liquid sulfur or commercially available qualified liquid sulfur products pose an explosion risk?
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Dear experts, in a sulfuric acid production plant, liquid sulfur needs to be introduced into the furnace for combustion; therefore, a liquid sulfur tank must be installed in the plant. I’m wondering whether this liquid sulfur could release H2S, which would act as an explosive gas and affect the determination of areas at risk of explosion. I’m waiting urgently for your advice.
As the original poster is concerned about, liquid sulfur does contain a certain amount of hydrogen sulfide during its production process (liquid sulfur produced by petrochemical companies usually contains more than 200 ppm of hydrogen sulfide), so there is a certain level of risk involved. There have been reports in the literature of accidents abroad involving liquid sulfur ships, where high hydrogen sulfide concentrations led to flash explosions. Therefore, liquid sulfur products usually need to undergo degassing before leaving the factory, in order to reduce the hydrogen sulfide content to below 10 ppm.
Well, your reply is correct – sulfur can only become a qualified product after degassing. What I wanted to ask is whether, when using degassed liquid sulfur in sulfuric acid production plants, the risk of explosion needs to be taken into consideration. Waiting for a response.
For degassed liquid sulfur, as long as hydrogen sulfide is kept below 10 ppm, there is no danger.
Does that mean no H2S was released? No need to consider H2S leakage and accumulation? Thank you very much for your reply.
The above concentration can be ignored.
I’d like to ask, is explosion protection taken into account in the sulfur molding and granulation workshop?
For this issue, the perspectives from design considerations and those from production considerations are different. The fact that hydrogen sulfide concentration is negligible in actual production does not mean it need not be taken into account during design. It is recommended to check the relevant specifications.
Well, thorough consideration is definitely needed during the design process; the safety of personnel and equipment is very important. Additionally, according to the standards, GB50058 specifies that if the concentration of flammable gases is no more than 10% of their lower explosive limit, there is no need to consider classifying the area as an explosive hazard zone. However, no one knows what concentration might be reached if a liquid sulfur tank storing liquid sulfur leaks; I wonder if this concern is unfounded
Yes, under these concentration conditions, there is no need to consider explosion prevention issues for molding and granulation. In fact, in most cases, it is difficult to achieve a level of 10 ppm through degassing, and there are no issues with molding and granulation.
My understanding: Consider the worst-case scenarios when designing. For example, in the event of an upstream degassing failure, the concentration of liquid sulfur in the liquid sulfur tank will be very high.