Location

Rolla, MO

Session Start Date

6-11-1999

Session End Date

6-17-1999

Keywords and Phrases

Mine Ventilation; Airflow Reduction; Heat Load; Thermal Conditions; Climatic Simulation; Automation; Equipment; Skin Temperature

Abstract

This study demonstrates the importance of ventilation in an automated mine through climatic simulations. These have been performed on workings located at depths of 1000 m to 3000 m below surface in an underground metal mine. Each active working area employs either an electric or a diesel piece of equipment that has a full load power output of 100 kW to 200 kW. The airflows considered in the mining areas were standard full-flow conditions, i.e. 100% (6.5 m3/100 kW), and 125%, 75%, and 50% of full-flow. The analyses show, for instance, that a 100 kW electric machine can increase the dry-bulb temperature in the working area at a 1000 m level, by 11.5°C (full flow) and 23.1°C (50% flow); at a 2000 m level, by 10.9 °C (full flow) and 21.9 °C (50% flow), and at a 3000 m level, by 10.4°C (full flow) and 20.6°C (50% flow). These relative changes are not affected by the full power output of an electric machine. The highest temperature observed for the electric machine was 58. 7°C at a depth of 3000 m and when only 50% flow is supplied. A I 00 k W diesel equipment producing 7 litre of water per litre of fuel consumed, or when about 50% of the total heat load appears as a latent heat, results in dry-bulb temperatures only 0.5°C higher than these generated by the electric machine. However, when the water content of the exhaust drops from 7 to 3 litres/litre of fuel, the dry-bulb temperature would increase by 7°C at full flow and 12°C at 50% flow. The highest temperature observed for the diesel machine was 71 °C. In this situation the worker mean skin temperature can increase to 15°C above the limit value, while the relative humidity may reach a value as low as 16%. Overall, through climatic prediction, the analyses show the continued importance ventilation in an automated mine. This is because of the heat from the machinery and the operational temperature limits of such machinery. Such elevated temperatures could also affect the operation of on-board guidance, sensors and image systems of remote-operation and automated mining equipment. Therefore it cannot be assumed that reduced airflow requirements would be the natural result of removing humans from an automated mine.

Department(s)

Mining and Nuclear Engineering

Appears In

U.S. Mine Ventilation Symposium

Meeting Name

8th U.S. Mine Ventilation Symposium

Publisher

University of Missouri--Rolla

Publication Date

6-11-1999

Document Version

Final Version

Document Type

Article - Conference proceedings

File Type

text

Language

English

Share

 
COinS
 
Jun 11th, 12:00 AM Jun 17th, 12:00 AM

Computer Simulation of Climatic Conditions for Underground Automated Mines for Standard and Reduced Airflow Requirements

Rolla, MO

This study demonstrates the importance of ventilation in an automated mine through climatic simulations. These have been performed on workings located at depths of 1000 m to 3000 m below surface in an underground metal mine. Each active working area employs either an electric or a diesel piece of equipment that has a full load power output of 100 kW to 200 kW. The airflows considered in the mining areas were standard full-flow conditions, i.e. 100% (6.5 m3/100 kW), and 125%, 75%, and 50% of full-flow. The analyses show, for instance, that a 100 kW electric machine can increase the dry-bulb temperature in the working area at a 1000 m level, by 11.5°C (full flow) and 23.1°C (50% flow); at a 2000 m level, by 10.9 °C (full flow) and 21.9 °C (50% flow), and at a 3000 m level, by 10.4°C (full flow) and 20.6°C (50% flow). These relative changes are not affected by the full power output of an electric machine. The highest temperature observed for the electric machine was 58. 7°C at a depth of 3000 m and when only 50% flow is supplied. A I 00 k W diesel equipment producing 7 litre of water per litre of fuel consumed, or when about 50% of the total heat load appears as a latent heat, results in dry-bulb temperatures only 0.5°C higher than these generated by the electric machine. However, when the water content of the exhaust drops from 7 to 3 litres/litre of fuel, the dry-bulb temperature would increase by 7°C at full flow and 12°C at 50% flow. The highest temperature observed for the diesel machine was 71 °C. In this situation the worker mean skin temperature can increase to 15°C above the limit value, while the relative humidity may reach a value as low as 16%. Overall, through climatic prediction, the analyses show the continued importance ventilation in an automated mine. This is because of the heat from the machinery and the operational temperature limits of such machinery. Such elevated temperatures could also affect the operation of on-board guidance, sensors and image systems of remote-operation and automated mining equipment. Therefore it cannot be assumed that reduced airflow requirements would be the natural result of removing humans from an automated mine.