TY - THES

T1 - Microwave irradiation treatment in the improvement of the performance of a Bucket Wheel Excavator

AU - Folgoso Lozano, Elena

N1 - embargoed until null

PY - 2020

Y1 - 2020

N2 - The Bucket Wheel Excavator, also known as BWE, is a mechanical excavation machine used in open pit mines, widely implemented in open pit coal mines. BWE can continuously work a regime: it digs, loads and hauls the material simultaneously. The material that a BWE can extract is limited by its strength. Normally, only loose or soft rock types can be loaded economically. Harder rocks are often preconditioned by blasting prior to excavation with a BWE. This research is demonstrating that the range of the material that a BWE is able to dig can be widened by pretreating the material with microwave irradiation, in order to reduce its the rock’s mechanical strength. The demonstrations consist of the direct comparison of both situations: treated and nontreated material. At first, the simulations are run in a hypothetical situation, using a wide range of material properties based on the Rock Mass Rating system. In the second step, the simulations include real data obtained by sensors installed on a BWE. Additionally, the energy consumption balance is calculated, including the data from the machine sensors as well as the data obtained in laboratory tests regarding the microwave treatment performed in previous research regarding microwave irradiation tests on rocks. The results show that after the microwave treatment on a specific material, the forces applied to the bucket wheel are reduced, due to the decrease of the cutting resistance of the material. Therefore, as a consequence, a proportional reduction in energy consumption will be also achieved, which confirms that the performance of the BWE’s extraction is improved.

AB - The Bucket Wheel Excavator, also known as BWE, is a mechanical excavation machine used in open pit mines, widely implemented in open pit coal mines. BWE can continuously work a regime: it digs, loads and hauls the material simultaneously. The material that a BWE can extract is limited by its strength. Normally, only loose or soft rock types can be loaded economically. Harder rocks are often preconditioned by blasting prior to excavation with a BWE. This research is demonstrating that the range of the material that a BWE is able to dig can be widened by pretreating the material with microwave irradiation, in order to reduce its the rock’s mechanical strength. The demonstrations consist of the direct comparison of both situations: treated and nontreated material. At first, the simulations are run in a hypothetical situation, using a wide range of material properties based on the Rock Mass Rating system. In the second step, the simulations include real data obtained by sensors installed on a BWE. Additionally, the energy consumption balance is calculated, including the data from the machine sensors as well as the data obtained in laboratory tests regarding the microwave treatment performed in previous research regarding microwave irradiation tests on rocks. The results show that after the microwave treatment on a specific material, the forces applied to the bucket wheel are reduced, due to the decrease of the cutting resistance of the material. Therefore, as a consequence, a proportional reduction in energy consumption will be also achieved, which confirms that the performance of the BWE’s extraction is improved.

KW - Schlüsselwörter: Schaufelradbagger

KW - BWE

KW - Mikrowellenbehandlung

KW - Schnittfestigkeit

KW - Bucket wheel excavator

KW - BWE

KW - microwave treatment

KW - cutting resistance

M3 - Master's Thesis

ER -