Part: Primary airflow estimate
The aim of this exercise is to estimate the primary airflow for a mine based on determining diesel dilution requirements, using bypass airflow requirements for auxiliary ventilation systems and leakage factors.
The mine is an underground metal mine located at a depth of 500m from surface. The mine does not anticipate any problems with heat and humidity or explosive gases or dusts. The mine plans to operate three through ventilated open stopes at a time and have three stopes in development using auxiliary ventilation. In the developments the primary diesel load consists of a 350 kW rated LHD loading out to a stockpile located in the main intake airway. Similar LHD's are also employed in the active stopes in conjunction with a 400 kW rated underground truck. In total the underground fleet consists of 6 LHD's and 5 trucks. In addition a fleet of light vehicles are also used underground (15 Toyotas rated at 250 kW each)
1. For a single development heading determine the required airflow for diesel dilution at the face of the heading if the requirement is for 0.05 m3/s of air per kW of diesel power?
2. If an allowance of 20% of the face end ventilation is required to cover leakage from the ventilation ducting what is the airflow required at the fan located in the intake airway?
3. If a bypass airflow of 25% is required to flow past the fan to stop recirculation what is the airflow required for a single development heading?
4. What is the total development airflow
5. For a single Stope determine the required airflow for diesel dilution if the requirement is for 0.05 m3/s of air per kW of diesel power?
6. What is the total stopes airflow?
7. If all the drives are 5m by 5m and the minimum airflow velocity requirement is 0.5 m/s do the airflows calculated in the previous questions cover this requirement?
8. Determine the total stoping and development ventilation flow
9. If am allowance for leakage of 20% is made what will the minimum primary airflow be for the mine?