Drilling and Completion Engineering
Cost Effective Drilling Systems
Today, the conventional drilling industry is using a very complex and therefore expensive way to drill wells. In many cases the effort to drill a well is unnecessarily high, which makes projects uneconomic or even not feasible. The industry is looking for more cost effective but safe ways to construct wells. Cheaper wells and a smaller environmental and logistic footprint would make projects feasible which are now uneconomic or impossible to realize.
Real-time Monitoring and Analysis
Modern drilling technology strives for high efficiency, increased safety and optimized processes. In order to deliver innovative solutions for future generations of drilling rigs, understanding the current drilling processes is of uttermost importance. The aim is to develop measurement systems that enhance the understanding of the various operations in the drilling process. In addition, real time data analysis techniques are applied to those systems to predict unfavorable events and to deploy counter measures in advance.
Well Life Cycle Management
To ensure a secure and environmentally safe wellbore over the whole life cycle of a well from drilling up to production, short and long term wellbore barriers are put in place. Key topics of the integrity of a well are the interaction between the various components which provide the integrity of the wellbore. There are evaluations of the long term risk, the cement/casing bond as well as the cement/rock bond.
The risk for future well integrity failures are assessed by taking into account historical cement data, available geology and possible long-term stress deformations. For the cement/casing bond the effects of local peak loads and changing hoop stresses in casing, resulting from temperature and pressure variations over the life time of an installation are studied. The adhesive forces between rock and cement are influenced by formation characteristics like in-situ stresses, porosity, permeability, wettability.
Petroleum and Geothermal Energy Recovery
Computational Fluid Dynamics (CFD)
For many years, the CFD group has been working on modeling of complex fluid flow and combustion problems. The software development activities are based on the open-source toolbox OpenFOAM and the commercial code FLUENT.
Main research areas include:
- thin film flows as can be found in the cleaning, painting and coating industries,
- multi-physics problems such as fluid/structure interaction in hydrodynamic bearings,
- drilling problems in particular modelling of gas-kick phenomena and
- complex non-isothermal fluid flow networks with focus on turbo-generator cooling.
Geothermal Energy Recovery
A sustainable source, geothermal energy and its recovery remain highly future-proof. We as petroleum engineers want to enhance the energy production from the earth by optimizing and developing new technologies, materials and media.
Sucker Rod Pump Systems
Worldwide, there are approximately 2 million oil wells and 37.5% of them use rod pumps as artificial lift method. Our goal is to optimize operations and develop technologies more efficient and capable to meet future requirements of our industry.
Recent research topics at our chair are:
- acoustical analysis of sucker rod pumps and
- dynamic behavior of the rod string, e.g. buckling prediction.
Ultrasound in Oil and Gas Industry
The ultrasonic technology provides a commercial and environment friendly solution to:
- treat different types of scaling, corrosion and precipitations,
- manipulate fluid viscosity,
- clean cuttings/sand contaminated by oil,
- optimize physical properties of cement and
- kill bacteria and algae in fluid media.
Reservoir Engineering
CO2 Sequestration
Due to the growing global demand for energy and the relatively slow transition to sustainable energy sources, the combustion of carbon-based fuels will remain the world’s major energy source for the coming decades. In order to achieve climate targets, transition technologies are required to reduce CO2 emissions during this period. Carbon Capture and Storage (CCS) is such a technology with a high potential to reduce greenhouse-gas emissions, and potentially even achieve a negative CO2 footprint. Research in the area of subsurface storage is typically focused on storage capacity and storage safety.
In this context, a currently ongoing PhD project is focused on the coupling of flow and geomechanics. The final goal is to model CO2 injection in fractured reservoirs with pre-existing faults and to estimate the effect of mechanics on flow and on storage capacity as well as estimating the risk of leakage and fault activation.
Despite the challenges and ongoing R&D, current knowledge and capabilities are sufficient to already identify safe subsurface containers in which CO2 can safely be stored. In particular, depleted gas fields and sandstone reservoirs are promising candidates for storage operations. But even in such cases, an elaborate effort of reservoir characterization and reservoir engineering is needed to guarantee safe storage and to optimize injection performance and storage capacity. Further R&D is focused on carbonate reservoirs. Those are more complex due to their multi-scale structural heterogeneities. Also the high reaction rate of carbonates with carbonic acid raises some challenges for predictive reservoir modeling and is hence a rich playground for research.
Geological Hydrogen Storage
Hydrogen is a very valuable source of energy. It can be produced from – e.g. – a surplus of renewable energy production or from heavy-oil production through upgrading. However, the production of large amounts of hydrogen needs the respective storage capacity to meet the demand. This is what we are working on.
The Reservoir Engineering group participates in a pilot project assessing the feasibility of large-scale hydrogen storage in a former gas field in Upper Austria (which should not be confused with – e.g. – the more developed small-scale hydrogen storage devices for – e.g. – transport applications). The target is the temporary surplus of wind and solar energy, which demands for storage capacity in order to cover for seasonal fluctuations of renewable energy production (www.underground-sun-storage.at).
We work on the chemical interaction between the injected hydrogen, the formation rock and the fluids in place. The target is to predict the stability of hydrogen in the reservoir as compared to the intended time scale of storage, which defines the purity and the value of the back-produced gas.
Improved and Enhanced Oil Recovery
A major part of the conventional oil reserves cannot be recovered by primary and secondary recovery methods. Tertiary processes or Enhanced Oil Recovery methods (EOR) have been developed to extract more oil from mature fields and enhancing recovery. However, EOR is typically expensive and is applied at high oil price.
Our aim is to establish the necessary numerical and experimental tools to better understand EOR processes on multiple scales (pore to field) in order to be able to develop low-cost options tailored to individual fields. The focus areas will be on water-based techniques such as alkaline and low-salinity water flooding and on CO2 EOR.
Upscaling of Porous Media Flow
Our primary research interest relates to multiphase flow in complex rock such as multi-porosity and fractured carbonates. Thereby we place emphasis on flow processes that dynamically change rock and fluid properties – i.e. reactive transport, wettability alteration, etc. – and their feedback to flow mechanisms. We aim to address these mechanisms on their natural length and time scales by state-of-the-art laboratory experiments, numerical interpretation and upscaling to the field-relevant scales.