The invention relates to improvements to patent of invention P200001758, "Method for the transformation of chrome-free tanning waste and products thus obtained", essentially consisting in dividing the continuous process described in said patent into two sequences or subprocesses. According to the invention, during the first sequence, the industrial waste used in the process can be optimized and the range of products to be obtained can be broadened, for example, fat, calcium salt and liquid solution of peptides. During the second sequence, the liquid peptide solution is transformed into a solution of free amino acids. The process can be extended to any liquid peptide solution regardless of the nature of the liquid, since said peptides originate from a source of animal protein or from a source of vegetable protein.