Experimental research on the performances of water jet devices and proposing the parameters of borehole hydraulic mining for oil shale

Abstract

Oil shale is an unconventional energy source, and it is also a potential petroleum substitute. Nowadays, the energy shortage is becoming more and more prominent, oil shale has attracted the attention of energy researchers all over the world. Borehole hydraulic mining is an effective method to exploit the underground oil shale which has more prominent advantages than other conventional mining methods. Jet devices are the key component of borehole hydraulic mining, which include the straight cone nozzle, organ pipe nozzle and self-excited oscillation pulsed jet nozzle. Also, the reasonable mining parameters are also crucial in mining underground oil shale efficiency. The jet characteristics of the non-submerged water jet, submerged water jet, direct water jet, cavitating water jet, and pulsed water jet are also explained and compared based on theoretical analysis. The jet performance of the non-submerged water jet is better than the submerged water jet. Each type of jet devices has its own basic principles and optimal structural parameters. The best operating scheme of borehole hydraulic mining for underground oil shale is to use the pulsed water jet which is produced by the self-excited oscillation pulsed jet nozzle to break underground oil shale under the non-submerged condition. Moreover, the pulsed water jet should be placed parallel to the oil shale bedding. In addition, under the preconditions of ensuring the safety and reliability of the hydraulic mining equipment and pipelines connection, the jet pressure and jet flow should be raised as much as possible, so as to obtain the much higher mining efficiency. These results and conclusions can provide very valuable guidance for borehole hydraulic mining of underground oil shale.

Bionic optimum design of straight cone nozzle and the effectiveness evaluation of reducing fluid resistance

“…The experimental setup is mainly comprised by the experimental bench, the power system of the water jet, the control and detection system, the fastening and motion system, and the fluid circulation system [7][8][9]. The setup can be used not only to detect the impact force of high-pressure water jet produced by the different nozzles, but also to implement experiments of breaking, cutting, or cleaning materials with high-pressure water jet.…”

“…The ordinary straight cone nozzle is a type of high-efficiency direct jet nozzle, which has been widely used in many different fields for years [5,6]. The straight cone nozzle mainly includes three parts: the access section (I), the contraction section (II), and the exit section (III) [7][8][9]. First, the access section (I) is used to connect the high-pressure hose.…”

“…High-pressure water jet technology (H-PWJT) is a clean and effective approach to clean and cut minerals and/or break mine ores. H-PWJT has been widely utilized resulting in remarkable social and economic benefits in several engineering and technical disciplines and may be combined with other technologies to develop new ones [5][6][7][8][9][10][11][12]. For example, the hydraulic coal mining and static pressure grouting technologies are combined to develop the highpressure jet grouting technology, which can be widely used in engineering fields such as rock and soil reinforcement and anti-seepage [13].…”

“…Nozzle is a fundamental component in the implementation of H-PWJT. The exploration of nozzle with good hydraulic performance is a key precondition for the smooth and efficient implementation of H-PWJT and other related technologies as the ones mentioned above [5][6][7][8][9][10][11][12][13][14][15][16]. This study proposes a combination of EB and nozzle's structural design.…”

Research on the Bionic Non-Smooth Nozzle for High-Pressure Jet Grouting Based on Computational Fluid Dynamics

“…In the practice, the straight cone nozzle is the most commonly used for HPJG, as shown in Figure 1 and Figure 2. The straight cone nozzle mainly consists of three parts: connection section, contraction section, outlet section [11][12]. For the normal nozzle, the all of the internal surfaces are smooth.…”