PKN ORLEN's first horizontall drilling
Today, PKN ORLEN has started drilling a horizontal well in the village of Syczyn, Wierzbica licence area, in the Lublin region. It is the second exploration well in the village. The work will continue for approximately two months. The next stage will involve fracturing of the horizontal well section, never before performed in the Lublin region.
After the first exploration well, 2,879 metres deep, was drilled in Syczyn at the end of 2011 and samples from the well were analysed, PKN ORLEN decided to continue exploration in the area. The new well will be the first horizontal well drilled in PKN ORLEN's exploration licence areas in Poland. A horizontal well comprises a vertical section and a horizontal section (Fig. 1). In Syczyn, horizontal drilling will commence at the depth of 2,700 metres, and the total length of the well bore will be approximately 4,000 metres.
"The design of the horizontal well provides for its location within the most promising strip of the explored shale formation. The planning and drilling of the well requires absolute precision. The most important thing is to drill the horizontal section exactly in the designated direction and at the optimum depth. The trajectory of the well should be designed taking into account the varying properties of shale. We have completed a huge amount of engineering work and are optimistic about the results of the drilling in Syczyn," said Wiesław Prugar, CEO of ORLEN Upstream.
As a result of the drilling work in Syczyn, 300 metres of rock core samples were collected at the end of the previous year. The shale was examined in terms of organic matter content and mechanical properties. The reservoir properties of the region's shale were also analysed in terms of porosity, permeability and crushability. The results prompted the decision to continue exploration in the area.
Once the horizontal well is drilled, a fracturing operation and production test will be performed. Recovery enhancement techniques, such as hydraulic fracturing, will be applied following the disassembly of the drilling rig, using specialist equipment. The critical phase of this short but complicated process will involve creation of controlled pressure, at which water will be pumped into the well to crack the shale rock open. As a next stage, sand with appropriate granulation will be pumped into the fractures. This will release gas from the rock and enable its flow through the borehole up to the surface.
The drilling work in the Wierzbica licence area will take approximately 60 days. The date of the fracturing treatment of the Syczyn-OU2K well will depend on a variety of factors, including weather conditions.
