KPO’s Production & Maintenance department is constantly assessing the latest developments in technology to help improve safety, reduce environmental impacts and maximise KPO’s production profile.
Over the last three years and in conjunction with leading service providers, a number of initiatives have been introduced which are enhancing the way KPO operates its facilities and pipelines.
Already highlighted as a major success for enhanced pipeline integrity and security is the introduction of a unique pipeline anti-intrusion system on the Karachaganak Atyrau Transportation System (KATS). This technology utilises the pipeline’s fibre optic communication cable to detect ground movement adjacent to the pipeline. Following a trial in 2008, the system has been further developed in 2009 with the expectation that it will provide greater pipeline security and operational cost savings from 2010 and beyond.
Plant ‘down-time’ due to corrective maintenance and prescriptive equipment inspections can have a significant impact on production and therefore it is essential to minimise both the number of interventions and intrusive vessel and piping inspections. To that end KPO has introduced two discrete corrosion and inspection databases. The software incorporates risk algorithms, helps to evaluate corrosion rates, track anomalies and calculate risk based inspection intervals.
In addition, the introduction of advanced non-destructive testing (NDT) techniques such as Long Range Ultrasonic Testing (LRUT) using ‘guided wave’ technology can help reduce excavations on pipelines and the removal of insulation on process piping.
Kazakhstan experiences major ambient temperature swings throughout the year and this can have a major impact on both gas disposal by re-injection and process capacity, particularly during the summer months. KPO is working closely with General Electric to re-power the three gas re-injection compressors to ensure that capacity is maintained during the summer months. Likewise, by developing and designing improved cooling capacity in the oil splitter overhead condensers, there has been significant improvement in the efficiency of the coolers such that the reduction in throughput capacity during the 2009 summer has been significantly less than previous years.
In summary, technological developments are playing a key role in KPO’s drive for continuous improvement.
Drag is defined as the frictional pressure loss that occurs over the length of a pipe during fluid flow. High pressure losses can be experienced in turbulent flow. These losses can lead to lower pump capacity and flow rates. Drag reducing agents are usually high molecular weight long chain polymers. These dissolve in the crude oil and lower the energy losses caused by turbulent flow resulting in lower pressure losses. With lower pressure losses, the same volume of crude can be pumped at lower pressures or more crude can be pumped at the same pressure.
Drag Reducing Agent (DRA) has been successfully applied to the Karachaganak Atyrau Transportation System (KATS) since 2005 and to the Karachaganak Orenburg Transportation System (KOTS) since 2007. This DRA has been specially formulated to be used in extremely cold climates and can still be pumped in the middle of a Kazakh winter where temperatures can fall to minus 40 degrees Celsius. At low parts per million injection rates its use has lead to improvements in the operating efficiency of both systems by allowing higher flow rates of fluids to be pumped.
The DRA is the same that is used in the CPC pipeline to Novorossiysk and has no impact on the quality of the crude oil or on refinery processes.
Unit 2 at Karachaganak is home to an innovative high pressure gas injection system. It processes and re-injects sour gas (H2S content of 4 per cent) at pressures of up to 550 bar and produces oil for stabilisation within the Karachaganak Processing Complex.
Oil and gas reservoirs primarily deliver oil, gas and water under pressure to the surface for processing and onward sale. The gas content of the reservoir stream is the driving force which allows for the extraction of the liquid hydrocarbons. Once the gas reaches the surface and is separated from the liquids, it reduces in pressure. In order to be able to return that gas to the reservoir, the pressure needs to be increased to a point where it is greater than the pressure of the reservoir. Gas injection is essentially the series of plant processes that increases the pressure of the gas and allows it to be returned to the reservoir.
Employing gas injection technology at Karachaganak brings a number of significant benefits. Firstly, given Karachaganak’s commitment to environmental protection, gas injection enables us to return the gas to the reservoir as opposed to flaring it or processing it on site. It also supports prudent reservoir management, delivering the gas back to the reservoir, maintains pressure and effectively extends the life of the field. This allows optimal hydrocarbon recovery over the life of the field which means that the Venture is able to produce more hydrocarbons for high value Western markets.
Unit 2 is part of a complex, integrated, interconnected and interdependent group of facilities which make up the operations of Karachaganak. The Unit has incoming production wells which feed into slug catchers where three phase separation takes place. The gas phase feeds dehydration trains which dry the gas for compression. The Unit’s compression systems comprises of three, re-injection compressors which have a combined capability to take 22 million standard cubic metres per day of sour gas from a 70 bar inlet pressure to a discharge pressure of 550 bar, returning it to the reservoir via a number of reinjection wells.