PHYSICOCHEMICAL PROPERTIES AND AGRICULTURAL USE OF SEWAGE SLUDGE FROM DIFFERENT INDUSTRIES

The present study, based on the reports on waste production in the Kujavia-Pomerania and Masovian voivodeships from 2007 to 2012, compares physicochemical characteristics of different kinds of industrial sewage sludge to the same characteristics of municipal sewage sludge. It turned out that physicochemical properties of such waste were related to the kind of industry that produced it. All sewage sludge used in agriculture met sanitary standards and regulations concerning heavy metal content (lead, cadmium, chrome, copper, nickel, mercury and zinc). It also had a high amount of nutrients. The highest content of nitrogen was in the waste produced by paper industry, the most phosphorus was in municipal sludge while the most calcium magnesium was in the waste from sugar industry. Sewage sludge from fruit and vegetable processing plants had a smaller heavy metal concentration than municipal sludge. The research proved that the sewage sludge from fruit and vegetable industry was the safest and could be used in agriculture to grow all kinds of crops.