Abstract: The present invention is related to a method for the preparation of a polyester, comprising the steps of providing a monomer slurry from a recycled monomer product and at least one diacid monomer, where the monomer product contains 50% to 97% of a condensation monomer and 3% to 50% by weight of a substance which is liquid at ambient conditions, and using the monomer slurry for the polymerization of a polyester, wherein the step of preparing said monomer slurry is executed in a way that allows to maintain the monomer slurry in liquid form. The present invention is furthermore related to solid particles comprising a recycled monomer product and a diacid monomer B at a mole ratio of B? units —OC—R2—CO— to diacid HOOC—R2—COOH in the range of 5:1 to 1:5. Further the present invention is related to a method for providing a recycled monomer product, where the monomer product contains 50% to 97% by weight of a condensation monomer and 3% to 50% by weight of a substance which is liquid at ambient conditions.