In this study, the process of adsorption of modified rice straw was described using a mathematical description using kinetic and isothermal models. The models of pseudo-first order, pseudo-second order, Elovich and Lynuiver-Burke were used as kinetic models, and the Langmuir model and the Freundlich model are isothermal models.

Keywords: adsorption, adsorption kinetics, adsorption isotherms, Langmuir, Freindlich

Examined the effectiveness of using aeration-lighting installation in the process of biological wastewater treatment.

Keywords: biological filter, biological treatment, energy efficiency, water treatment, lighting, aeroblast, biomass, activated sludge, microorganisms, aeration tank, aerator

Examines the factors affecting the rate of reproduction and the efficiency of interaction of micro-algae for example Chlorella in polluted waters in order to clean them. Grounded energy and economic efficiency of using sunlight to intensify the process of cultivation of Chlorella.

Keywords: microalgae, Chlorella, energy efficiency, water treatment, lighting, aeroblast, biomass

Considered the prospect of using solar energy in the Rostov region. Calculations of energy consumption for hot water needs, parameters of solar collectors and volume of the storage tank. Considered seasonal and year-round use of solar energy. It is established that it is more profitable to use flat solar collectors in the Rostov region for seasonal use.

Keywords: solar energy, solar collector, energy efficiency, energy saving, solar radiation, the correction factor, heat exchanger, the demand