MINE VENTILATION
Howden recently delivered the first phase of a 8 MW surface bulk air cooling plant for Roxgold ’ s Yaramoko gold mine in Burkina Faso
CONTROL customers for such cooling functionality , according to Dello Sbarba , with these clients realising the benefits that could come with controlling the process from the underground readings , assessing where cooling was most needed .
“ While the actual capital cost associated with the cooling plant installation is unlikely to change – given these plants should be sized by engineers on a worse-case scenario basis – you should definitely see significant improvements in terms of the operating and energy cost of the plants ,” he said .
This economic benefit is complemented by the health and safety advantages already mentioned .
“ At the moment , miners tend to put a chilling plant on surface and just cool the air regardless of where it is destined to go ,” Dello Sbarba said . “ This process doesn ’ t consider the fact that the only reason you are cooling air on surface is for the deeper levels of the mine that experience particularly high temperatures .
“ You currently don ’ t have intelligent control of this cooled air across the underground mine .”
With Howden ’ s cooling on demand module within Ventsim CONTROL , users can monitor if they are obtaining the required temperatures at these deeper levels , making sure the cooled air is pushed to where it needs to go .
Aside from a subscription to Ventsim CONTROL with at least Level 3 and 5 functionality – providing required set points for airflow , gas levels , and / or temperature – and the right-sized ventilation fans , users only require temperature and humidity sensors underground to carry out such control .
“ Even though you need many of these monitors , they are relatively cheap with many hardware solutions available on the market ,” Dello Sbarba said .
Equipped with these elements , users can assign certain temperature / humidity setpoints in areas of high activity , plug these setpoints into Ventsim CONTROL and allow the software to
‘ communicate ’ with the cooling plant and fans to automatically cool these areas to the required temperature . An advanced Level 5 installation of Ventsim CONTROL allows the users to automatically optimise underground fan and regulator settings and adjusting main fan settings to maintain required cooling levels while maximising energy savings .
He concluded on the subject : “ The reason it is advantageous to perform cooling on demand with Ventsim CONTROL over other solutions is the 3D modelling capabilities within the software . The model helps you predict and better control your air flows based on what you are seeing in the simulation .
“ It has an edge over any other custom-made ventilation engineering solution on the market .”
When Dello Sbarba spoke to IM in early June , the new cooling on demand functionality was in the final throes of testing in a factory setting . A mine site trial was being lined up for later in the year too .
He also flagged the potential for a ‘ heating on demand ’ solution where mines are not limited to stay above freezing point at the shaft collar . Such control would result in significant energy savings and reduced greenhouse gas emissions which comes in line with the low NOx-emissions heaters provided by Howden that many northern mines currently rely on .
One of the other new major features of Ventsim CONTROL is the ability to offer advanced connectivity with third-party software . This ensures data can be exchanged and Ventsim CONTROL can mirror the control abilities of any SCADA system .
Dello Sbarba explained : “ In the market , we were seeing a lot of mines wanting to keep on using their existing software and standardise on a given SCADA . This provides them the ability to do so .”
This year , Howden has been very busy signing agreements with other third parties to ensure it remains a ‘ total ventilation solutions provider ’ in the mining space .
A recent pact with VortexOHS could see the company gain further market share in South Africa and neighbouring countries in the near term , while setting the company up to provide the sophisticated occupational health and safety platform global mining leaders will soon require , according to Dello Sbarba .
The company ’ s software improves safety by assisting ventilation and occupational hygiene professionals to collect , manage and report data and information from their occupational health and safety sampling programs . It streamlines the process , reducing the administration burden and cutting costs , Dello Sbarba explained .
“ VortexOHS is a software widely used across South Africa , meeting the regulation needs of the South African government in terms of air sampling and reporting ,” he said . “ South Africa is by far the most advanced in terms of mine ventilation reporting – it is the only one that has such high standards – but I strongly believe the rest of the world will strive to meet those same standards over time .”
And , as previously mentioned in this article , Howden has teamed up with Maestro to integrate several Maestro products into Ventsim CONTROL .
“ Maestro ’ s products are purpose built for underground mining , having been tested over a really large installed base ,” Dello Sbarba said . “ At the same time , Ventsim CONTROL is a high quality , purpose-built offering for the industry . This is where we see a good fit in terms of integrating their hardware with our software .
“ It is about two best-in-class products coming together for a best-in-class ventilation solution .”
That optimal ventilation solution is , according to Dello Sbarba , making the industry transition towards battery-electric vehicle use that much easier , ensuring that the combination of the machine and ventilation system is right sized from the off and the economics stack up .
“ Howden ’ s goal here is to support mining operations in making their project more feasible whether it is from a capital or operating expenditure basis ,” he said . “ Miners looking at battery-electric vehicles can come to us for a full evaluation of their ventilation needs that ensures the system they employ is safe , affordable , consumes as little energy as possible and – increasingly important nowadays – comes with the lowest greenhouse gas footprint .”
Measure to optimise
Zitrón has also designed an intelligent ventilation management system for mining that , it says , can optimise underground air flow for a significant improvement in working conditions and an up to 40 % reduction in energy consumption . “ The rationale is to direct air where it is needed and in the volume that is required , to have safer working conditions , to increase productivity and to reduce energy consumption ,” the company explained . “ All this translates into a faster return on investment due to energy savings , reduced carbon emissions and greater guarantees in both safety and system reliability .”
Zitrón says it wants to streamline the ventilation process , eradicating the need to consult several complex 3D representations of ventilation circuits offering up difficult to
14 International Mining | JULY 2021