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The article presents a study of the state of the real estate market in the context of the new coronavirus infection “CoVid-19”. The influence of the pandemic on this market is shown on the example of one of the subjects of the Russian Federation - the Irkutsk region. A solution has been proposed for the efficient operation of enterprises in the conditions of a recession in the construction of real estate, which consists in reimbursing the lease of real estate to small and medium-sized enterprises on certain conditions. Preliminary calculations have been carried out, which have shown the effectiveness of the reimbursement of rental space to enterprises. The basis for such calculations was the concept of increasing tax profits obtained from deductions from enterprises to the regional and federal budgets. The conditions that the company must accept as obligations in case of a positive decision regarding the reimbursement of rent payments from the regional budget are given. Eight indicators have been identified that give a definite economic effect to the regional budget. The conclusion is made about the expediency of reimbursing rent payments to small and medium-sized businesses.

In this paper, an intensification of wastewater flotation treatment by exposure to vibration is studied. Exposure to vibration results in the decrease of air bubble size, increase of air flow through the aerator and more even dispersion of air bubbles in water. This intensifies the aeration process, thus significantly improving the treatment efficiency. A multistage model of flotation kinetics has been applied in order to take into consideration the effects of vibration. The model gives a thorough explanation of the flotation process with consideration of 'air bubble - contaminant particle' aggregate formation. A large series of experiments was conducted with paint and varnish industry wastewaters. It is shown that vibroflotation results in an increase of treatment efficiency by up to three times. A comparison of the experimental data with the results of mathematical modeling is presented, showing a good correlation of theoretical and experimental results.

This study develops a new model for description of flotation kinetics. It defines flotation as a process that consists of several stages: separated air bubbles and particles, air bubbles and particles forming an aggregate, aggregate rising to the froth layer. This description significantly differs from known models, which are much simplified. The multistage model gives a novel in-depth description and considers different aspects of flotation, i.e. aggregate formation, which is critically important for flotation to take place. Experimental approval of the new model resulted in its accuracy. The model is to be used for a description of kinetics of all flotation processes in wastewater treatment. It helps in accurate design of flotation treatment plants and may be used for further research of the flotation process.