“Natural gypsum” board
hudson_valley_gregg
| Posted in Green Products and Materials on
I’m looking for a source in the states of natural gypsum board. Seems simple, non? I Googled “natural gypsum board”, and an incredibly limited number of hits (30 compared with thousands or millions for most searches) arrived, and only Alibaba and an Indian site seemed to offer succor. Hmm.
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What would be “unnatural” gypsum? It’s a mined product, dug out of the ground, basically. I don’t think anyone is making synthetic gypsum.
Do you maybe mean “unfaced” gypsum board? That’s usually a special order item.
Bill
Zephyr,
Q. "What would be 'unnatural' gypsum? It’s a mined product, dug out of the ground."
A. You're only half right. Some gypsum comes from mines, but a significant amount of gypsum comes from the flue gas desulfurization process. For more information, see these articles:
"Introduction to FGD Gypsum"
"What is gypsum?"
"Synthetic Gypsum"
That is interesting Martin, thanks for the info. I was familiar with some of the uses for the fly ash from power plants, but I was unaware of a process that essentially results in gypsum production from the plant byproducts.
There are several large gypsum mines in northern Michigan and I know much (probably most) of that goes into drywall production but I don’t know at which plants.
For the original poster, perhaps if the manufactures won’t provide info as to their materials sources, choosing gypsum produced at wallboard plants near gypsum mines may at least make it more likely that the plants are using the nearby mines when sourcing raw gypsum. As I understand it, gypsum occurs naturally in vast quantities so it’s inexpensive to mine. I was completely unaware of alternate sources for that particular raw material.
Bill
Thanks, Martin.
As you know, an increasing percentage - probably the vast majority now - of "gypsum" is harvested "pre-consumer" at coal-fired power plants; e.g., National Gypsum writes, "Byproduct Gypsum is the ultimate recycle. It comes from a process that removes sulfur dioxide from emissions at coal-fired power plants. After the power plants remove fly ash and other impurities from the coal combustion exhaust air, the air is fed through a limestone slurry which removes the sulfur dioxide from the exhaust. The byproduct of this process is calcium sulfate, the chemical name for gypsum. Five National Gypsum plants produce wallboard exclusively with byproduct gypsum: Shippingport, PA; Apollo Beach, FL; Mt. Holly, NC; Westwego, LA; and Shoals, IN. Two of our plants – in Baltimore, MD and Waukegan, IL – use a combination of byproduct gypsum and natural gypsum rock in its wallboard production."
No manufacturer as far as I can tell indicates what materials are the boards. American Gypsum, however, cheerfully features this passage on its wallboard pages: "American Gypsum products contain no asbestos and no detectable levels of formaldehyde." What a relief?
Gregg,
I'm not sure why you are (apparently) ridiculing the posted information on asbestos and formaldehyde. That is information that green builders need to know, and I'm glad that American Gypsum provides that information.
I'm glad that coal plants are equipped with scrubbers that remove sulfur dioxide from the flue gas. If gypsum is produced as a byproduct of these scrubbers, I see nothing wrong with using the gypsum. But if you have personal reasons to prefer mined gypsum -- note that open-pit mines have their own environmental downsides -- I wish you luck in your quest.
Martin, as a green builder you might support the absence of formaldehyde from the entire production process - as opposed to the infusion and purported removal of it within the production process. Even more to the point, American Gypsum may as well indicate "American Gypsum products contain no human remains and no detectable levels of plutonium": For me as a standards-driven manager, knowledge of product and process - including what constitutes the bloody product in the first place - is a million times more interesting than what's NOT in it.
As for ensuring coal-burning power plants remain economically viable by investing directly in its by-products via pre-consumer recycling, I think it's wonderful that you have that option as a green builder. I again seek only clarity and transparency from someone - anyone - in the supply chain regarding the provenance of the materials constituting the product. National Gypsum's passage on the provenance of some of its gypsum if not the rest of the materials in its boards, for instance, is helpful to a standards-driven manager. If you have professional reasons to prefer investing in coal-burning power plants - note that coal-burning power plants have their own environmental downsides - I wish you only the best.
Gregg,
I'm happy to end this dialog on a note of agreement. Like you, I think all coal burning power plants should be shut down, as rapidly as possible.
The engineers who invented a method of removing sulfur from smokestack emissions, and the legislators who mandated the use of these scrubbers, were well-intentioned. The aim was to reduce air pollution. But I understand your point -- we don't want to be burning coal anymore.