Design and Output Performance Model of Turbodrill Blade Used in a Slim Borehole
Small-diameter turbodrills have great potential for use in slim boreholes because of their lower cost and higher efficiency when used in geothermal energy and other underground resource applications. Multistage hydraulic components consisting of stators and rotors are key aspects of turbodrills. This study aimed to develop a suitable blade that can be used under high temperature in granite formations. First, prediction models for single- and multi-stage blades were established based on Bernoulli’s Equation. The design requirement of the blade for high-temperature geothermal drilling in granite was proposed. A Φ89 blade was developed based on the dimensionless parameter method and Bezier curve; the parameters of the blade, including its radial size, symotric parameters, and blade profiles, were input into ANASYS and CFX to establish a calculation model of the single-stage blade. The optimization of the blade structure of the small-diameter turbodrill enabled a multistage turbodrill model to be established and the turbodrill’s overall output performance to be predicted. The results demonstrate that the design can meet the turbodrill’s performance requirements and that the multistage model can effectively improve the accuracy of the prediction.
Hot dry rocks: An inexhaustible and renewable source of energy
Geological, methodological, and economic aspects of the production and utilization of petrother mal resources (heat of “dry” rocks) for electric energy production and heat supply are considered. Possibility of the utilization of natural fracture zones or artificial fissure zones, which are created by hydraulic fracturing of underground rock massifs, is noted. Application of new tools for drilling deep wells makes the petrochemical energy competitive relative to both other types of renewable resources and traditional organic fuel.
Effect of HS and Pressure Depletion on the CO MMP of Zama Oils
Phase behaviour and minimum miscibility pressure measurements were carried out to evaluate the potential of applying miscible CO 2 /H 2 S flooding in the Zama reefs of NE Alberta, Canada. Since there is some variability in the properties of oils from different wells or reefs, the measurements were carried out on recombined reservoir fluids from two different wells. The injection solvent will be supplied from a nearby gas plant that is expected to produce CO 2 /H 2 S streams with a range of compositions due to a number of operational factors. Accordingly, three solvent injection gases were considered: pure CO 2 and CO 2 containing 20 and 40 mol% H 2 S. Minimum miscibility pressure (MMP) measurements were carried out using the rising bubble apparatus (RBA). The MMP decreased almost linearly with the amount of H 2 S in the injection gas in the range of compositions studied. Some evidence of precipitation of solids was observed. Measurements were also carried out to determine the CO 2 MMP of these reservoir fluids as they were depleted of gas through a differential liberation procedure. The results show that the MMP decreased with decreasing liberation pressure. Key properties of the liberated reservoir fluids were also measured and compared with those of the recombined reservoir fluids. The results show that miscible flooding with sour acid gas is feasible in this case, and could provide an excellent means of storing/sequestering these gases while improving oil recovery.