The amount of production of the organic fertilizers and their introduction in recent years have fallen sharply, that reduced to a negative balance of humus in soils, made worse fertility and coused productivity of agriculture. The perspective way of restocking of organic matter in soils is the use of sewage sludge as fertilizer.
However, the contents of some metals in it limits the use in agricultural production. Taking into consideration some negative impact on soil excessive amounts of metals that contained in sewage sludge, such as iron and manganese we should comprehensively assess the possible consequences of its entering into the soil and identify the main patterns of accumulation of these elements in it.
To establish the dynamics of the content of certain patterns of trace elements in sediment of sewage sludge samples were taken from the maps that in the WWTP CE “Ivano-Frankivskvodoecotechprom” for 8 years.
For storage of sewage sludge significantly reduced the concentration of iron and manganese, respectively, 12.0 and 12.3 mg/kg, then described the dynamics of this relationship regression equation and correlation coefficient using the methods of mathematical statistics.
Calculated and constructed regression equation of iron and manganese, which indicates a direct relationship of iron and manganese in the sediment of waste water. For mathematical regression function constructed linear relationship between iron and magnesium. This dependence also obeys a normal distribution. According to the data, with the results of iron content in sewage sludge can find the content of manganese.
In modern conditions the real way to prepare sewage sludge to use as fertilizer in agriculture should be considered for dewatering sludge composting with subsequent maps of various organic fillers.
Composting of sewage sludge with organic and mineral fillers (sawdust, straw, cement dust) as a result of an opportunity to get high quality fertilizer. After the composting process, compost derived from sewage sludge with the addition of chips were the loose friable mass, which had no odor, and compost using straw particles were observed incompletely decomposed straw.
The compost from sewage sludge observed a significantly lower content of microelements. According to the research, the lowest content of iron and manganese was in the compost № 2 of sewage sludge + straw (3: 1) – 20 t/ha.
Key words: sewage sludge, agrochemical composition, fertilizers, micronutrients.