cleanse them of oxygen in between each load going in. 0ver there, you have the tins they go in and the packer, and you may or may not know that carbon dioxide also goes inside the tins to make sure your bs day is pure. 0ver the tins to make sure your bs day is pure. over here, we have the beer pumps themselves to make sure your beer stays pure. carbon dioxide is used to push the liquid out and into your glass. let s remind ourselves about why there has been so much tension around the supply of carbon dioxide. it has been well covered, the wholesale gas price has more than doubled since january because of increased demand and reduced supply. prices have got so high that some businesses couldn t afford to go on. cf industries makes fertilisers here in the uk and carbon dioxide is their main