With modern Ventilation on Demand (VoD) systems, when used correctly, African mines have the right tool at their disposal to manage the huge energy costs they incur in demanding ventilation tasks in the deep-level environment.
Mines face two tough decisions in the way they manage their ventilation requirements in the deep-level mining environment – stick with the conventional and bear the huge energy costs or opt for the cost effective Ventilation on Demand (VOD) technology and stay afloat. And the choice is entirely in their hands.
But if they are to stay in business in the contemporary operating environment sustainably for as long as possible the latter makes business sense. This fact was stressed during the high profile tenth International Mine Ventilation Congress (themed Managing Mine Ventilation Systems in the Modern Context: Meeting Mining, Economic, Sustainability, and Health and Safety Challenges), which was held in South Africa in late 2014. And it continues to be echoed in various forums globally.
No hidden agenda
There is no hidden agenda by Original Equipment Manufacturers behind to peddle their latest VOD innovations.
The reality is that decision makers or whoever is responsible in mines have to look beyond their fixation and sentimentality with conventional ventilation methods and ensure that their businesses continue to be profitable in the face of an increasingly rising running costs. And they have to seek convenient tools.
In deep-level mining, where huge volumes of contaminants and fumes are emitted, good airflow and quality creates a favorable environment for people and equipment to work. Ideally, every part of the mines which are operational should be ventilated. But practically, it is farfetched, as more financial resources would have to be committed towards energy costs
However, if the objective is saving costs, mining would have to be restricted to only an area where there is proper airflow and quality. This approach could stall productivity in other parts.
The cost-need balance
Plainly, the dilemma is that efficient ventilation is the pulse of mining yet is it very expensive to sustain. How can the cost-need balance be addressed then?
Of a host of alternatives, so far the veracity of VOD continues to be established in several scenarios.
Though it has been in existence for a long time, modern VOD is more rugged and toughened for the mining environment. Through specifically targeting areas that are needed, not only does VOD drastically reduce the amount of energy needed and greenhouse gas emissions, but also ensures the safety and well-being of the miners beneath the surface.
In a review, Tanveer Jahir and Mohamed Mohamed, two experts from a leading Canadian provider of VOD systems for mines, Conspec Controls Limited, underscore VOD’s relevance: “VOD is achieved by monitoring the air quality in target areas of the mine, and based on variables such as the number of personnel in the area, the number of emission-emitting vehicles, the air leakage around doors and entrances, dust levels, and other key environmental details, the speed and angles of the fan blades are adjusted to increase or decrease the volume of air flow.”
Through VOD, the fans can be turned up and down according to a predetermined work schedule i.e. only where activity is taking place, hence needed the most. This can significantly contribute to cost reduction (which can account to anything between 35 to 50% of underground energy consumption).Ultimately, mining processes, people and equipment are optimised and productivity is increased.
Valid business case
There is a very valid business case for deep-level mining operations to incorporate VOD in their ventilation management systems. The gains to be had go beyond the visible lowering of ventilation energy costs. The main benefit of the investment could be more visible in increase in revenue, of course in the medium to long term.