Gazprom Neft’s Omsk refinery advances work on water treatment system

PJSC Gazprom Neft subsidiary JSC Gazpromneft-ONPZ has started installation of additional equipment for its previously announced biosphere closed-loop wastewater treatment plant as part of the second phase of the operator’s ongoing modernization program to reduce environmental impacts and improve processing capacities, conversion rates, energy efficiency, and production qualities at its 430,000-b/d Omsk refinery in Western Siberia (OGJ Online, Feb. 8, 2017).

Installation of flotation-treatment systems is currently under way as part of construction of the biosphere treatment plant that, once in operation, will guarantee up to 99.9% water purity to enable the refinery to return more than 70% of treated water to production, reducing the burden on municipal wastewater treatment plants, Gazprom Neft and Gazpromneft-ONPZ said.

The flotation system forms part of the biosphere’s multistage water treatment process, during which all industrial effluents and storm drainage from the plant will pass through mechanical, flotation, and biological treatment installations, as well as membrane and charcoal filters.

Specifically, the pressure-flotation technology implemented at the biosphere complex will enable removal of oil-product residues from water by aerodynamic flows in special hermetically sealed containers.

Three of the nine flotation units planned for the project have already been installed at the construction site, and installation of equipment for the tank unit responsible for initial mixing of the full volume of industrial water before it is sent for further treatment also has been completed, the operator said.

Installation of the complex’s disinfection and biological treatment units remains ongoing, according to Gazprom Neft.

Once in operation, the biosphere complex’s main unit—the bioreactor—will receive water to be mixed with a special sludge containing microorganisms that absorb oil-product residues. The cleaned waster will then also be disinfected with ultraviolet light and returned to the production cycle, while recovered petroleum products will be sent for recycling, allowing the refinery to reuse the purified water and reduce its water consumption by more than twofold.

Installation of the biosphere’s flotation treatment systems follows Gazpromneft-ONPZ’s previous start of installation activities in March on key equipment for the complex’s filtration, disinfection, and biological treatment units (OGJ Online, Mar. 27, 2020).

Scheduled for startup in 2021, the 19 billion-rubles biosphere treatment project—which comes as part of the Russian federal government’s master plan for its Clean Air and Ecology projects adopted under a decree from President Vladimir Putin in May 2018—will include a multistage water-purification system composed of mechanical, physical, chemical, and biological treatments, as well as capabilities for carbon filtration and ultraviolet disinfection, according to the operator.