Large volumes of non-processed deposits from the municipal and industrial sewage purification works, which contain pathogenic microorganisms, heavy metals, rotting and toxic chemical substances, are a dangerous resource of environmental pollution.
The most economical and safe method of deposit processing is the method of "wet combustion" at high temperature and pressure. 150 plants using the technology, which was based on this method, were working in 1980 in Europe, in the USA and in Japan. The obtained ash residue was buried in most cases.
We suggest the technology of oxidizing and hydrolytic destruction of the deposits which, contrary to the "wet combustion" method- resulting in ash and carbon dioxide, allows to obtain on a certain stage some valuable products with preliminary separation of heavy metals. This technology gives no waste materials and in the case of proper organization of production allows to compensate all expenses within 2-4 years, due to the sale of the obtained products. The products of the processing have being subjected to wide scale tests during several years, which has enabled us to choose the priority directions of their application in agriculture and industry.
The stand plants has been constructed in St.Petersburg and in town of Vyborg. The construction of the plant for processing biogenic deposit, according to the suggested technology, is being finished in the town of Novouralsk. The design operations are carried out for the plant's installation in the sewage purification works in the towns of Pskov, Naberezhnye Chelny and Chelyabinsk.

The process of oxidizing-hydrolytic destruction is a combination of oxidizing and hydrolytic destruction of the organic substance which is contained in the biogenic deposits. It simulates the natural process of humification of the organic substances of these deposits in soil. Natural processes of humification are results of biochemical oxidation and further conversions of organic substances, which continue for several years. In an industrial plant, these processes are considerably accelerated by high temperature and pressure. It reduces the lime of the raw material processing in the reactor plant to several hours. The yield and the composition of the districted products depend on both the composition of the initial raw materials and the processing conditions (temperature, pressure, period of time, pH value, air consumption). The processing of the biogenic deposits in alkali medium transforms the heavy metals into hydroxides, which have low values of solubility products, and enables their conversion into non-soluble residue (NSR). A part of organic acids, which are formed at the oxidation, enters into stable coordinated connections with metal ions. It also leads to the occurrence of non-soluble compounds, which can be separated from the target product.

The main commercial product is an ""oxidate"" comprising either of 30% water solution or a dry powder-like mass. The chemical components of the product are related mainly to the polyoxicarbon or polioxiphenolcarbon acids of humin substance type, which are represented as salts in the solution.
The comparison of the properties of this product with such preparations of humin nature as "Veneta mineraria", Italy, "Aldrich" Great Britain, "Fluca", Switzerland, which are advertised on the international market, has shown their identity.

Many years of tests on a batch of the "oxidate" of biogenic deposits, which were carried out by specialized agricultural institutions, have shown, that it has got a stimulating effect, can influence the intensity of the certain physiological processes and provides an effective increase of different crop harvest. The recommendations for agricultural measures have been developed, which make the use of the "oxidate" especially effective. Thus the application of the "oxidate" increased average harvest of cucumbers 14-23%, tomatoes - 35-39%, root crops (carrots, beets) - 14-16%, grain-crops (flax, oats, barley)- 19-26%, potatoes- 27-33%, cabbage - 30-33%. It has been noted, that the "oxidate" has a clearly expressed, prolonged effect, which enables an increase of the harvest for the next year 10-14%, without adding the "oxidate" once more.
The application of the "oxidate" effects positively the quality of the agricultural products changing their biochemical compositions, contents of sugar, vitamin C, carotene, biotin and starch; simultaneously, the nitrate content decreases in all cultures 3-4 times in comparison with the control samples.

The technology of manufacturing organo-mineral fertilizers has been developed on the basis of mineral fertilizers (ammophos, superphosphate, azophoska) and the "oxidate" of the biogenic.-deposits as an organic component. Such a fertilizer increases the uniformity of the mineral fertilizer solubility, and decreases toxicity of high concentration of feeding substances for plant roots, what enables finally to decrease the consumption of mineral fertilizers.
Many years of tests on large amounts of the organo-mineral fertilizers, with additive of humin substances obtained from biogenic deposits, increased the harvest of potatoes 27-35%, of grain-crops (oats, barley)- 10-15%. The application of such fertilizers decreases the consumption of mineral fertilizers for 25% at a constant level of the harvest. The application of the organo-mineral fertilizers decreases the content of nitrates in the Finished products.

Addition of 5-10% of humates, obtained from the "oxidate", to mixed composts stimulates sharply the growth of bacterium during the first 2-3 weeks of composting; this allows the composts in a shorter period of time, in comparison with the traditional technology, to be formed. Hereby, all groups of the microorganisms, which are responsible for degradation of the plant's raw materials (bacterium, fungi, Actinommycetes), are developing well; the activity of the cellulose degrading fungi increases especially.
The application of the composts for potatoes with concentration of 40 t/hectare provides such a harvest as if with full mineral fertilizing. At the present time the recommendations for application of the "oxidate"s in agriculture, for the composting of different mixed composts, are being developed.

The application of the "oxidate"s as additives to flushing liquids for geological exploration drilling, stone-cutting and metal working, and as a component of liquid lubricants and coolants of emulsion type (LLC), is being developed. Manufacturing of such components is limited by lack of raw materials and high requirements to ecological characteristics of emulsion concentrates. The "oxidate"s have been tested as a corrosion inhibitor in solution of sulfuric acid for carbonic steel protection. It was shown that the "oxidate" is in 1,5-2 times more effective for washing of thermal power plants with the concentration of sulfuric acid 5 g/l, than the traditional inhibitor - urotropin. Positive results were obtained when the "oxidate" was used as an additive to cooling water for internal combustion engines.
One of the most promising directions of the "oxidate"'s applications may be its use as a raw material for the manufacturing of sorbents and complexons for purification of liquid radioactive wastes, containing radounuclides of Cs-137, Ba-133, Ce-144, Eu-153 and Co-60 type. The preliminary tests have shown the effectiveness of this direction in comparison with traditionally used deficient components of Trilon B or ion-exchange resin type. The "oxidate" obtained from slime deposits of wood processing enterprises can be used for manufacturing highly effective dyestuffs and mordants with antiseptic properties for wood, paper and cardboard. Besides the "oxidate" the non-oxidized residue (NSR) can be used as a commercial product containing the heavy metals, in form of non-soluble compositions with the mineral residue. The NSR has been tested as a burning out additive in the production of claydite. At the present time a workshop using such technology is being designed. The works for application of the NSR for road surfacing, in construction industry and in other fields are being carried out.

The above represented materials and the scientific and engineering projects of our enterprise allow us to suggest to interested municipal institutions, organizations and potential investors lo create, on the basis of existing sewage purification works, the plants for the processing of slime deposits with realization of obtained products. The initial development of a standard plant, with the yield of 4-5 m3 of deposits/hour (with humidity of 90%) with its consequent copying for other enterprises, seems expedient. Our organization can carry out the following works: development of a feasibility study, working design, the provision of standard and non-standard equipment, supervision of assembly, adjustment and alignment, participation in trial operation and in realization of the finished products.

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