Sewage sludge, depending on its preparation and local conditions will still constitute waste material for storage or a product to be used in nature. Due to its fertilizer value, sludge originating from treatment process as its by-product may be used for fertilization or reclamation of green areas. Obviously, to be used in nature the sludge must be properly prepared in processes allowing for removal of toxic compounds, which might negatively affect the quality of crops cultivated on it.Rational agricultural production bases on observing rules to improve soil fertility and its productivity through application of proper cultivation measures, including mineral and organic fertilization. Soils of Poland usually reveal poor abundance in organic matter and when more demanding plants are cultivated in them, the amount of humus decreases rapidly and they become nutrient impoverished. Farmyard manure is the most popular organic fertilizer used in agriculture. After the year 1990 farmyard production declined considerably due to reduced animal production and the currently used doses are insufficient to obtain good yields. Therefore it is necessary to seek new alternative sources of organic matter which might be safely used as an alternative fertilizer.Alternatives to FYM fertilizers include various types of ...
Sewage treatment aims mainly at protection of the natural environment and primarily protection of surface water purity. Sewage treatment process is always accompanied by sewage sludge, which is defined an organo-mineral solid phase of sewage. Chemical composition of the sludge my be different depending on the kind of treated sewage and applied processing technologies. Sewage sludge constitutes about 2% of the total volume inflowing to sewage treatment plants. Construction of new sewage treatment plants and intensification of treatment process cause an increase in the amount of produced sewage sludge and raises its storage costs, which may be very high, reaching even 50% of total costs generated by a sewage treatment plant. An alternative for storing large amounts of sewage sludge may prove its natural utilization, which would also contribute to reduce costs born by sewage treatment plants. Some previous research has already demonstrated sewage sludge usability for the following purposes: reclamation of devastated lands, plant consolidation of ground surface or composting sewage sludge. However, agricultural utilization of sewage sludge still raises numerous controversies. It is due mainly to insufficient information about sewage sludge. However, research results convince that the problem of sewage sludge is worth ...
