Pile delignification

The present invention relates to a delignification method which is applied for removing lignin from a biomaterial mixture in form of a pile, and essentially comprises the steps of piling of the biomaterials, treating the pile with an irrigation solution comprised of water or an aqueous solution comprising chemical materials, transferring the irrigation solution leached during reaching to the bottom of the pile to a pool or a storage unit with a drainage system, giving the irrigation solution which is transferred to the pool or the storage unit to irrigation again after controlling and optimizing, and leaching the pile by stopping the irrigation when the delignification process ends.