Context: Paper recycling processes can use either chemically or mechanically produced pulp; by mixing it with water and applying mechanical action the hydrogen bonds in the paper can be broken and fibres separated again. Most recycled paper contains a proportion of virgin fibre for the sake of quality; generally speaking, de-inked pulp is of the same quality or lower than the collected paper it was made from.

Question: What type of processes can only use chemically produced pulp?
Answer: Unanswerable

Question: What type of processes can only use mechanically produced pulp?
Answer: Unanswerable

Question: What does most water contain for quality sake?
Answer: Unanswerable

Question: What quality does inked pulp generally have?
Answer: Unanswerable

Question: From what paper does de-inked pulp generally have a higher quality?
Answer: Unanswerable

Question: What's the third way paper recycling process can use?
Answer: Unanswerable

Question: What does mixing it with milk do?
Answer: Unanswerable

Question: How much non-recycled paper contains virgin fibre?
Answer: Unanswerable