Probiotic Foods

Erschließung geothermischer Lagerstätten mittels Hochdruck‐Wasserstrahl Bohrtechnik

“…Inside a vertical well, a geothermal reservoir is accessed in horizontal direction within an open-hole section at a depth of 500 m. As RJD targets at presenting a low-cost alternative to conventional stimulation technologies like hydraulic fracturing and matrix treatments [2], a rather shallow reservoir depth of 500 m is regarded to keep the scale of a prospective operation small and cost-sensitive. Moreover, sandstone formations present viable reservoirs for RJD application as is shown in Saikia et al [1]. For this purpose, a high-pressure pump, limited to a maximum operating pressure of 750 bar, is connected via CT and highpressure hose with a multi-orifice jetting bit.…”

“…High-pressure water jet drilling technologies like Radial jet Drilling (RJD) are current and prospective stimulation treatments with frequent reference in both academia and literature [1,2]. Initially designed as a fit-for-purpose treatment for marginal hydrocarbon reservoirs, RJD technology has gained momentum in geothermal research and industry as an alternative and bypass to shunned hydraulic fracturing treatment for indispensable reservoir stimulation and permeability enhancement in shallow and deep geothermal wells [3,4].…”

“…To predict the success of the jetting treatment, a modelling framework is developed describing the downhole hydraulics and mechanics for a RJD operation in vertical and inclined wellbore sections as well as the interaction between high-pressure water jet and reservoir rock. The developed modelling framework focuses on granular rock types limiting its applicability to sandstone reservoirs suitable for geothermal exploitation [1].…”

“…That said, fluid exiting the front orifices erodes the rock surface, whereas fluid exiting the backward-oriented orifices creates propulsion force [6]. Coiled Tubing (CT) and a hose comprise a conduit from surface to treatment depth for the circulation system, with the nozzle being mounted atop [1]. Like in conventional drilling, an annulus facilitates the return of flow to the surface during the treatment.…”