Gas Hydrates
With the failure of BP's recent attempt to control the blowout being attributed to the formation of gas hydrates, I thought it might be helpful to discuss hydrates in general. A gas hydrate is a crystalline structure that forms in cold temperatures under high pressure. The crystal is formed with water molecules surrounding a hydrocarbon molecule and resembles ice...ice that will burn.
Hydrate formation is something the oil and gas industry has been fighting for some time. These crystals are an unwanted obstacle to production and they can form whenever the conditions are right (composition, temperature and pressure). The offshore environment, especially deep water, is particularly susceptible to the formation of hydrates both in producing wells and in underwater pipelines.
The usual treatment for dealing with hydrates is first to attempt to design around them (try to keep the product from entering the hydrate formation envelope) but if that doesn't work, to treat with chemicals that will "melt" the crystals-- usually methanol. And in fact I read where BP is considering a "top hat" device that will allow for methanol treating to melt the hydrates.
Here is a link to a Texas A&M article on hydrates which has more information and discusses naturally occurring hydrates as a potential future energy source.
