<[email protected]> wrote:
> Plastic bags are made primarily of hydrocarbons. > > 1. Dissolved in a solvent, they might make a useful diesel fuel. > 2. Bundled and compressed the bags might be burned instead of coal. > 3. Added to a blast furnace, they could replace, or augment coal. > Trash incinerators are used to produce energy in some places. Unfortunately they cause a lot of pollution. The problem with plastic bags is that the total mass is small, and the plastic is scattered around. Bringing it all to one place would take a lot of energy. Think of how many plastic bags you use in your daily life. Grocery shopping bags, Saran wrap, the bags used packaging in new computers, plastic sheets at Lowe's used to keep plants from soiling the back of your car, and so on. It seems like a lot, but if you were to gather a whole month of that plastic, and burn it, it would burn up in no time. It would be nothing compared to the coal or natural gas that is burned to provide you with electricity. People who cut and burn firewood to heat their houses have gigantic mounds of wood, the size of two or three pickup trucks. That's just the fuel need for space heating. Wood has low energy density, but not that low. 16 MJ/kg versus 24 MJ/kg for coal. See: http://energyeducation.ca/encyclopedia/Energy_density People use large sheets of plastic in some industries, where they unpack delicate parts, for example. It might make sense to gather up the plastic in a factory and burn it or recycle it some other way. There are recycling bins for plastic grocery bags. I suspect this is not economical but it is better than scattering the bags around the landscape. They cause great harm to wildlife. - Jed
