PURPOSE: To recycle refuse incineration ashes from an incineration furnace of municipal refuse and industrial waste as a water holding material, subbase course material, soil improving material, concrete aggregates etc., by adding and mixing a pH control agent for controlling a mixture formed by adding surplus soil of construction to the refuse incineration ashes described above to prescribed pH to and with the mixture and pelletizing, briquetting or press forming the mixture and curing the resulted pellets, briquettes, etc., at a prescribed time.

CONSTITUTION: This process for production of the recycling materials from the refuse incineration ashes, sewage pollutant incineration ashes, etc., comprises first adding the pH control agent for adjusting the pH to 11.0 to 11.5 to the mixture mixed with at least ≥2 kinds among the refuse incineration ashes generated from the incineration furnace for the municipal refuse and industrial waste, the flying ashes of the refuse incineration furnace, sewage contaminant incineration ashes and coal ashes and the surplus soil of construction at need. The pH control agent-added mixture is pelletized or briquetted or press formed under water spraying. The pellets, etc., are then cured for the prescribed time. As a result, the refuse incineration ashes having a possibility of elution of heavy metal ions, etc., and the surplus soil of construction to which much moisture is stuck, is sticky and is not easy to handle are recycled.