With all the various claims among paper manufacturers regarding the sustainability of their products, it's hard to know what's really going on. Doc wasn't sure what the definition was for "flotation deinking" or "mill broke," at least not until now. Thanks to a good basic glossary at What They Think, I'm now a lot better informed. Here are just a few of the definitions listed:
Deinked Market Pulp (DMP) – Pulp made from recovered paper by mills that receive high-grade deinking papers (defined below) and remove the ink and contaminants. DMP is produced in sheets as wet-lap pulp (about 50% moisture) or air-dried form and is sold to paper producers who blend it with virgin pulp for use on existing paper machines.
Deinking – The separation and removal prior to paper formation of ink and other contaminants from wastepaper slurry by screening, washing, flotation, chemical treatment and bleaching.Fiber Furnish – Recovered paper used to make paper or board with recycled content.
Flotation Deinking – In a paper recycling system, removal of ink by a process of adding surfactants to the pulp and pumping bubbles of air through the mixture. The hydrophobic ink particles attach to the air bubbles, float to the surface of the pulp and are skimmed off.
Mill Broke – Any paper or paperboard scrap generated in a mill prior to completion of the manufacturing process which is unsuitable for subsequent applications but can be re-used in the paper manufacturing process.
Many of these definitions come from a glossary developed by the Environmental Defense Fund, which also has a free Paper Calculator to help you estimate the environmental impact of your paper choices. You can find that calculator and the full glossary of terms here.