Example of air exchange arrangement and its calculation
for a sewerage network section under design

Summary

The method of calculating the volume and direction of gas travel in the sewerage network induced by the fluid carrying capacity and natural draft with account of different physical, hydraulic parameters of wastewater and gas, network design values, daylight surface temperature is presented. The method provides for making calculations at the design stage and determining the following parameters: the volume and direction of gas travel in the network, gas exchange rate, network corrosion rate, expected background concentration of corrosive gases at the assigned gas exchange rate, network corrosion rate, overhaul period. Herewith commissioning ventilation installations, filters and vent pipes is taken into account. To obtain the regularities for calculating and designing air exchange facilities in the operating urban tunnel sewers numerous experimental studies were carried out. Herewith the basic calculation formulas of the joint travel of fluid and air were obtained and the calculation method of determining the basic parameters of air exchange systems was developed. This method was used in the process of designing the Ufa wastewater disposal system expansion. The conducted economic comparison takes into account the basic technical and economic parameters of the ventilation system operating parameters; provides for assessing approximately different ventilation options and carrying out their comparison and calculating the economic effect.

Key words

collector , sewerage network , ventilation , gas exchange , air exchange calculation method