TNGG: APG Utilization at Russian Oil Fields
M. N. Gagarin (LLC TyumenNIIgiprogaz)
In the Russian Market, there are almost no widely available cheap technologies to collect and process associated petroleum gas, or APG. Similar technologies and projects can be found abroad, but these can be very expensive and would also need to be adjusted to Russian climatic conditions and legislation. Also, the penalty fines for air emissions are much less than the costs for APG utilization.
At TyumenNIIgiprogaz, we pay a lot of attention to APG utilization when we are designing process solutions for oil and gas fields and infrastructure development. Indeed, we achieve 100% APG utilization when we deliver our engineering projects.
For over 5 years, our projects at the KS-1 and KS-2 compressor stations at the Central Gathering Facility-1 and 2 from the Urengoy oil and gas condensate field has been completed with an APG processing plant, which is used for gas lifting. The remaining gas, that has been dried at low temperatures during separation, is then fed into the gas trunk pipeline. By using this APG as a lifting agent, we do not have to use the Valangian age gas for this purpose. The development and implementation of the complex solutions for the modernizing and upgrading of the production technology and the efficient use of APG at the Urengoy field won TyumenNIIgiprogaz an award from Gazprom in 2011. The amount of APG used at the KS-1 and KS-2 compressor stations totals 1280 mln.m3/year.
The key process and compressor equipment for KS-1, 2 were manufactured by OJSC SMNPO, named after Mr M.V. Frunze from Sumy, Ukraine. They are double hulled, three-stage centrifugal compressor units – ТКА-Ц-8БД/0,3-8,16 – with 80MW gas turbine drive units. These compressor units are placed in the hangars, where intermediate vessels and gas boots are used for fluid catching, after the interstage and end cooling of the compressed gas in the air-cooling units.
The emission reductions total 102,000 tons per year from compressor station KS-1 and 86,000 tons per year from KS-2, when there is no flaring and when, of course, the compressor stations are being used. Both stations were part of the program entitled “Utilization of associated petroleum gas at the Urengoy oil and gas condensate field” which was implemented in line with the Kyoto protocol.
The gas compressor station (GKS-1) at Tomskgazproms Kazanian oil and gas field was constructed as per our design and has now been in operation for over 2 years. APG from the second phase gas compressor station was delivered in 2013.
At GSK-1, the compressor units were designed by Ariel, and the gas turbines by Caterpillar. There are four similar compressor units at GSK-2. The compressor units at GSK-1 have reduced emissions by 8.5 thousand tons per year. Once GSK-2 has been commissioned, we will be able to reduce emissions by a further 12 thousand tons per year due to a further reduction in APG flaring.
We have also designed an integrated gas and condensate processing unit at another Kazanian oil and gas field that uses compressed APG. This is unique because it can process unstable condensate that is released while processing dried gas obtained by low temperature separation methods with the use of turbo expanders, and stable condensate and propane/butane at the mass-transfer apparatuses.
The total potential of APG at both compressor stations will be roughly 1000 M.m3/year if the field is fully developed. The construction of an Integrated Gas and Condensate Processing Unit is also in progress. As per the contract with Tomskgazprom, we are delivering a Gas Compressor Station project for the utilization of APG, including gas from the Terminal Separation Unit at the Severo-Ostaninskoe oil and gas condensate field which is fed to the Myldzhinskoe Integrated Gas Processing Unit. The total potential APG utilization will be roughly 470 M m3/year.
