Experience of retrofitting the technology of wash water utilization at the Omsk water treatment facilities

Summary

The main phases of addressing holistically the problem water source pollution with wastewater generated at the Omsk water treatment plant are considered. The results of technologic pre-engineering that provided for determining the optimal flow scheme of the treatment process and filter wash water reuse as well for defining the process parameters of combined treatment of river and wash water are presented. It is shown that the chemicals mainly used for drinking water purification can be used for filter wash water treatment. The studies were carried out by test coagulation method, i. e. by adding various amounts of polluted wash water and chemicals used at the water treatment plant into raw river water. The efficiency of combined treatment of river water is improving with increasing the amount of added polluted wash water. The design concepts and process flow scheme of water treatment that provided for constructing and commissioning filter wash water reuse unit with minimum capital expenditures are presented. The operating experience affirmed the correctness of the adopted process and design solutions. As a result the abstraction of raw river water was reduced by 9–13% and wash water discharge into the Irtysh River- the water source was completely abandoned. Wash water treatment is carried out together with raw river water at the water treatment facilities. Herewith the drinking water quality fully meets the requirements of Sanitary Regulations and Norms 2.1.4.1074-01.

Key words

water treatment , reagent treatment , wash water , water reuse , resource conservation

Estimation of the possible use of wastewater thermal energy
for the auxiliaries of the treatment facilities

Summary

Through the example of the wastewater treatment facilities of Mayachnyi village in the urban district of Kumertau (Republic of Bashkortostan), the possibility of using the thermal energy of effluent to heat incoming wastewater in order to enhance the biological treatment process, as well as for heating buildings, is studied. A heat recovery scheme with the transfer of thermal energy for heating wastewater in a surge tank using a surface heater «jacket» mounted inside the tank of the pipe register or in a heat exchanger «pipe-in-pipe» installed downstream the tank is considered. The required heat output of the heat pump unit has been determined, and the design parameters of various heat exchange units have been calculated. The technical limitations that complicate using a «pipe-in-pipe» heat exchanger and pipe registers have been identified. The possibility of heating incoming wastewater to 18–25 °C has been demonstrated.

Key words

wastewater , ecology , heat pump , power efficiency , resource conservation , secondary thermal energy , recovery