Several years ago we had to have a new septic system put in (thru no fault of ours) and they guy that did it said you can throw some hamburger down your toilet or septic and it will break up the bacteria and works well. He also put "T joints" in the system to prevent tiny things from clogging the whole thing up and saving the new system. I can't remember what all he said about the T joints, but they seem to be working.
I have washed a twin and crib size rag quilt in my washer with no problems, the larger ones I take to the laundromat and use the big industrial size washer. Then I dry them at home.