Location: GLO - Global
This datasets represents purification of helium, crude to helium Grade - A and its liquefaction. The technology used for helium purification is pressure swing adsorption (PSA) and liquefaction unit. The dataset is based on literature and estimates. The uncertainty of the data is rather high.
The activity is mass unbalanced due to missing "used charcoal" exchange.
Undefined unit processes (UPRs) are the unlinked, multi-product activity datasets that form the basis for all of the system models available in the ecoinvent database. This is the way the datasets are obtained and entered into the database by the data providers. These activity datasets are useful for investigating the environmental impacts of a specific activity (gate-to-gate), without regard to its upstream or downstream impacts.