01-19-2015, 12:08 PM
Ironyak - there appears to have been a typo - or at the very least, a numbers-conflict in the 200 tons per day you cite. If you look at that same report, under the heading Summit Observations, you will see the statement cited by Vancouver Islander: "The emission rate of sulfur dioxide ranged from around 4,500 to 7,600 tonnes/day during the week ending January 13." Clearly a much higher number than 200 tons per day you cite - and I understood that it was about a 50/50 split between the summit and ERZ sources.
Your statement:
No, not agreed. l looked at that Volcano Watch you noted and the claims there don’t match the known chemistry of H2S and SO2 - which can quite happily coexist for days at a time together. The Klaus reaction, one of the primary manufacturing methods for elemental sulfur reacts these two gases together, but require a catalyst to make the reaction work effectively (even at high temperature). It is known that these two gases rapidly react together in the presence of liquid water – and it’s likely that this reaction will consume some of the H2S present in the eruptive gases in a condensing plume but, to my knowledge, no one has actually made the effort to determine what fraction is lost to that process.
The other volcano watch article you noted is equally off base with the chemistry of the eruptive and geothermal emissions (natural and man-made). The relative ratio of SO2 and H2S in the volcanic gases is related to which sulfur compound is more stable at a given temperature (as well as the kinetics of the conversion from one to the other). Sulfur dioxide is the more stable compound in the high temperature eruptive gases; hydrogen sulfide is the more stable compound in equilibrium with the other gases at lower temperatures. When we have an eruption in lower Puna, we’ll see plenty of sulfur dioxide – water or not.
Certainly can agree that H2S and SO2 are different compounds - and that they have different physiologic effects. And, as the Bates study showed (and the CDC report cited also substantiates), that the levels of exposure to H2S detected around the PGV plant, have, to date, posed no health threat to the community.
Your statement:
quote:
Volcanic SO2 emissions recorded by USGS are not the same chemical as H2S which PGV was fined for. The H2S that is released by the volcano is quickly decomposed as opposed to H2S from geothermal areas. Agreed so far?
No, not agreed. l looked at that Volcano Watch you noted and the claims there don’t match the known chemistry of H2S and SO2 - which can quite happily coexist for days at a time together. The Klaus reaction, one of the primary manufacturing methods for elemental sulfur reacts these two gases together, but require a catalyst to make the reaction work effectively (even at high temperature). It is known that these two gases rapidly react together in the presence of liquid water – and it’s likely that this reaction will consume some of the H2S present in the eruptive gases in a condensing plume but, to my knowledge, no one has actually made the effort to determine what fraction is lost to that process.
The other volcano watch article you noted is equally off base with the chemistry of the eruptive and geothermal emissions (natural and man-made). The relative ratio of SO2 and H2S in the volcanic gases is related to which sulfur compound is more stable at a given temperature (as well as the kinetics of the conversion from one to the other). Sulfur dioxide is the more stable compound in the high temperature eruptive gases; hydrogen sulfide is the more stable compound in equilibrium with the other gases at lower temperatures. When we have an eruption in lower Puna, we’ll see plenty of sulfur dioxide – water or not.
quote:
Originally posted by ironyak
So can we agree that H2S is not SO2, H2S from Kilauea's summit vents is quickly neutralized, and that H2S is the primary gas seen in geothermal areas?
Certainly can agree that H2S and SO2 are different compounds - and that they have different physiologic effects. And, as the Bates study showed (and the CDC report cited also substantiates), that the levels of exposure to H2S detected around the PGV plant, have, to date, posed no health threat to the community.