Annotation: The article is devoted to the development of a technology for obtaining organic fertilizers from poultry waste based on biocatalytic processes. Currently, many poultry farms have become sources of environmental pollution, thereby causing serious environmental problems and economic and social damage. The problem of reliable protection of the natural environment from pollution by bird droppings is currently relevant. In the area of operation of large poultry farms, air pollution by microorganisms, dust, foul-smelling organic compounds, which are decomposition products of organic waste, as well as nitrogen, sulfur, and carbon oxides, is possible. Bird droppings contain acids, nitrogen, phosphorus and potassium, heavy metals. The content of nitrogen, phosphorus and potassium changes dramatically depending on the quantity and quality of the feed. Humic substances isolated from brown coal have a sufficiently high sorption activity and are used as cheap sorbents for solving a number of environmental problems in industry. These studies are aimed at minimizing the main disadvantage of the anaerobic digestion process, the low reaction rate, which leads to the need to create large-volume bioreactors. On the basis of the research carried out, a technology has been developed for obtaining organic fertilizers from poultry waste by the method of anaerobic fermentation of chicken manure with humidity at a temperature of 27 °C - 50 °C with the addition of sodium humate. The resulting fertilizer is intended for use in agricultural production, horticulture, floriculture, forestry, municipalities, in household plots in order to increase the yield and quality of crop production. For the developed technology, an application has been submitted for obtaining a Patent for the invention of the Republic of Kazakhstan «Method for producing organic fertilizers» (priority No. 2021-22818, dated July 13, 2021). The invention allows to significantly reduce the time of fermentation, to enrich the product with organic and mineral products contained in sodium humate, to convert the salts of heavy metals into an insoluble state, to improve the environmental friendliness of the method.

Annotation: Singularly perturbed partial differential equations with small parameters with higher derivatives deserve special attention, which often arise in a variety of applied problems and are used in describing mathematical models of diffusion processes, absorption taking into account small diffusion, filtration of liquids in porous media, chemical kinetics, chromatography, heat and mass transfer, hydrodynamics and many other fields. It is necessary to consider the creation of an asymptotic classification of solutions of singularly perturbed equations using a well-known approach to solving the boundary value problem. In this case, the singular problem is understood as the problem of constructing the asymptotics of the solution of the Cauchy problem for a system of ordinary differential equations with a small parameter with a large derivative. The asymptotics of the solution in all cases is based on the last time interval or the construction of a boundary value problem for a system with a weak clot in an asymptotically large time interval. Purpose - to construct and substantiate the asymptotics of solving a singular initial problem for a system of two nonlinear ordinary differential equations with a small parameter; To date, a number of methods have been developed for constructing asymptotic expansions of solutions to various problems. This is the method of boundary functions developed in the works of A.B. Vasilyeva, M.I. Vishik, L.A. Lusternik, V.F. Butuzov; the regularization method of S. A. Lomov, methods of averaging, VKB, splicing of asymptotic decompositions of A.M. Ilyin and others. All the above methods allow us to obtain asymptotic expansions of solutions for wide classes of equations. At the same time, such singularly perturbed problems often arise, to which ready-made methods are not applicable or do not allow to obtain an effective result. Therefore, the development of methods for solving equations remains a very urgent problem. As a result of the study, an algorithm for constructing an asymptotic classification of the initial solution of the problem with a singular perturbation is given, and approaches to estimating the residual term are also shown.