From the just-arrived Newsletter of the U.S. Bishops’ Committee on Divine Worship: how do you dispose of an old sacramentary?
Though little is written about it, it’s an important topic. The Book of Blessings says that the sacramentary, lectionary, and other liturgical books are to be blessed, although the official Latin (De Benedictionibus) doesn’t mention the missal explicitly in this regard.
The BCDW recommends burying the old sacramentary on church grounds or in a parish cemetery. Other possibilities are placing the liturgical book in the coffin of a deceased person, as is done in various Eastern Churches, as a sign of the person’s devotion to the liturgy. One could also do ‘cremation’ (my term, not theirs) and bury the ashes on church grounds. Suggestion: keep one copy of the book for the parish archives.