The responsible use of water resources, effective wastewater treatment, and preventing oil and oil products from reaching natural water basins are all important areas of focus in Gazprom Neft’s comprehensive environmental programme. The company uses the latest available environmental protection technologies in undertaking such initiatives.
Oil refineries are heavy users of water. For that reason, projects directed at reducing water consumption and improving efficiency in wastewater treatments are an important part of the environmental element in Gazprom Neft’s refinery modernisation programme.
Obsolete outdoor treatment facilities at the Moscow Refinery were replaced with new automated closed-loop treatment complexes in 2012 — something of an ecological revolution for the plant locally, with the result that atmospheric impacts in wastewater treatment reduced by 97 percent, while purification of waste water (i.e., waste removal) reached 95 percent.
The “Biosphere” treatment complex at the Moscow Refinery
2017 saw the start of a new phase in the Moscow Refinery’s history, with the commissioning of a new “Biosphere” treatment complex involving not just mechanical and physical—chemical systems, but also biological purification, filtration and ultrafiltration, including a reverse osmosis unit with microporous membranes. Launching the Biosphere has allowed the enterprise to increase its wastewater treatment efficiency to 99.9 percent, exceeding the performance of the best refineries in Europe. The plant has also reduced its consumption of river water
The “Biosphere” treatment complex at the Omsk Refinery
The construction of new closed-loop treatment facilities forms an important part of the full-scale modernisation programme at the Omsk Refinery. By order of the Government of the Russian Federation, the Omsk Refinery treatment complex is included in the Federal Plan for initiatives as part of the “Year of Ecology” in Russia.
The new facility, developed by Russia’s PAO ONHP, will utilise an advanced multi-stage water purification system involving mechanical, physical—chemical and biological purification, as well as carbon filtration and ultraviolet sterilisation. Thanks to this system, up to 70 percent of treated water will be returned to the plant’s production cycle, reducing the burden on municipal treatment facilities. All treatment processes will have full watertight integrity throughout, preventing the evaporation of any oil products into the atmosphere and reducing atmospheric impacts from the Omsk Refinery’s treatment facilities by 95 percent.
The new treatment facilities are expected to be commissioned in 2019.
Offshore operational safety
Optimising the risks of any negative environmental impacts is one of the overriding objectives in implementing the first offshore production project on the Russian Arctic Shelf — the development of the Prirazlomnoye field.
A range of cutting-edge technological solutions are in use at the Prirazlomnaya offshore ice-resistant fixed platform (rig) that production is being conducted from, allowing any impacts on the Arctic environment to be kept to the absolute minimum. Under “zero emissions” technology, used drilling mud, slurry and other wastes are either re-injected into a special absorption well, or returned to the mainland for disposal.
There is no possibility of the well coming into contact with the aquatic environment around the Prirazlomnaya rig because the structure is installed directly on the bottom of the Pechora Sea, at a depth of 19 metres. Oil storage is located in the bottom of the platform, in what is known as the “caisson” (a gravity-based sub-structure ). For greater protection against corrosion and wear, its walls comprise a four-centimetre layer of clad steel, with the three-metre space between the walls being filled with heavy-duty concrete. The construction of the caisson has been designed to withstand a collision with almost any vessel, or even a torpedo attack. A specialist paint and varnish coating has been used to protect against high humidity and the aggressive marine environment, together with cathodic anti-corrosion and anodic protection systems.
Specialist equipment is installed at the wells to prevent any accidental oil spill, capable of closing off oil-lifting, at depth, if necessary. “Wet-sump” technology is used in the oil-storage tanks, ensuring that these are always full or either oil or water, eliminating any risk of an explosive environment forming. Oil is loaded only in the event of 30 essential conditions being met, simultaneously. The tanker loading line is equipped with an emergency termination and shutdown system that can, if necessary, stop shipment operations almost instantaneously. Round-the-clock monitoring of the offshore ice-resistant fixed platform is facilitated through specialist sensors, instantly transmitting any changes in its operation.
The likelihood of an accident directly in a tanker, within Gazpromneft Shelf’s area of responsibility, is also extremely low. Depressurisation of the oil storage facility on the tanker can occur on collision with another vessel or on running aground, but this is almost impossible near the platform. Nevertheless, such risk is taken into account in oil-spill response (OSR) planning, with response-readiness ensured through regular specialist OSR exercises.