First off you should not start a new thread when discussing the same project from another thread. Doing so will not give a new reader the background of the project and what you plan to install on the floor.
You can't really get rid of it without using chemicals which will drive some of it deeper into the subfloor and create a bond-breaking situation. You have to cover it, or use a type of new flooring that is compatible.
TILE GUY - retired- TROY, MI - Method & Product suitability consulting.