ARTIFICIAL SLUDGE BASED ON COMPOSITIONAL INFORMATION OF A NATURAL SEA SLUDGE

Abstract

The chemical and physical properties of sludge collected from different aquatic areas differfrom one another. Such differences have made the universal standardization of early settings difficult. Usageof artificial sludge with stable characteristics has been thus proposed in the present study. First, values oforganic matter, sulfide content, and the inorganic content were measured for the sea sludge collected fromFunabashi Port in Japan. Using the obtained chemical and physical properties as reference, we then producedartificial sludge by mixing dry yeast made from yeast cultured in liquid sodium sulfide nonahydrate solutions(3.5-4.0%) and zeolite for inorganic material. In the present study, we understood that we couldn’t obtain thedesired organic content for the artificial sludge, simply by adding the yeast with the amount similar to theorganic content percentage we aimed. We thus calibrated the amount of yeast by measuring the actualorganic content of several artificial sludge samples by thermo-gravimetry analysis. We found out that weneed only to write a calibration curve of three measurements (zeolite-dry yeast w/w% = 0%, mid-point, and83.3%) in order to obtain the information about the right amount of dry yeast addition to produce an artificialsludge with desired percentage of organic material. Finally, we mixed 31.4% of dry yeast (zeolite and otherinorganic materials = 68.6%), in order to obtain an artificial sludge with 23.6% organic content. Thispercentage is similar to the organic content of the sludge collected from Funabashi Port.