What site doesn’t want to increase their stockyard capacity? The frustration of having nowhere to stack, shutting down process plants, or facing in-loading delays is all too common. StacksOn™ provides a cutting-edge digital twin system for bulk material stockyards, delivering a method to increase overall capacity, enhance working flexibility, and improve stockyard operations—all without the need for costly capital works. 

Why StacksOn?

• Boost capacity: Increase overall stockyard capacity without costly upgrades
• Maximise reclaiming: Unlock more material available for reclaiming
• Enhance flexibility:  Adapt your stockyard to changing needs with ease 
• Manage grades better:  Improve grade control and material tracking 

Filling in the gaps

When we look at a stockyard from the point of view of stockyard capacity, the first thing we notice is the areas of wasted space between the stockpiles. What if we could fill in these areas? What would be the consequence of such a change?   

The long arm of the reclaimer

The first thing to consider is your reclaimer’s reach. Often the reclaimer extends its boom past the end of its rails to increase its range and maximize the stockyards footprint. In a typical yard, as shown below, most stockpiles are reclaimed in the “forward” direction. The reclaimer will however turn around to reclaim a couple of stockpiles in the reverse direction to use its reach to good effect. 

If the goal is to fill the gaps between stockpiles to increase capacity, it might make sense to leave one strategic gap. Advanced modelling can help determine if this approach is suitable for your site. Figure 3 illustrates how modelling identifies the optimal length for a continuous stockpile. Naturally, the position of the gap between the piles can move further right as required.  

Eating your own Tail

The next aspect to consider is how you use your yard currently and how the new yard layout will be used. Typically, the new yard layout will employ continuous stockpiling, which essentially means that the stacker continuously extends the head stockpile, whilst the reclaimer continuously gobbles up the tail.  

All you can eat buffet

This results in substantially greater usable capacity. Let me explain. Consider the following scenario in Figure 5. The poor reclaimer has nothing to reclaim. Adding insult to injury, there is a full stockpile, but you would take a risk in shipping material that hasn’t been sampled. Let’s imagine now that the right-most stockpile was also empty, the only stockpile left is being blocked by the stacker.  You could bump the stacker to another pile and reclaim it, but the reclaim rates would be terrible with low and/or narrow benches.  

Consider a similar scenario but with a continuous stockpile as shown in Figure 6. The reclaimer is at an all you can eat buffet! It first reclaims nice, sampled material. Then, if the stacker’s feed is down, it reclaims unsampled material which is better than nothing. Finally, if the reclaimer catches up to the stacker, the stacker is simply bumped down the yard 15 meters and the reclaimer has access to the material previously blocked by the stacker. And the best part of this buffet, the reclaimer gets to eat at its maximum rate as there are no low or narrow benches, even when it bumps the stacker to a new pile. 

Filled to the brim

So, what’s the story with stacking? Well, with traditional stockpiling, as shown in Figure 7, the reclaimer blocks a portion of the yard, even if the stockpile is close to empty. You can bump the reclaimer to another pile, but it was in the meat of the pile with good reclaim rates. It may also delay the train if it is in the middle of loading. And what if the stockpile on the right was full due to an out–loading shutdown? Then you have nowhere to go with the stacker and must shut down the plant. 

Now let’s consider what would happen if we combined the right three piles into a continuous stockpile. By removing the two gaps, you get extra capacity before you catch up to the reclaimer. Plus, if you are in an out–loading shut, you can park up the reclaimer and fill in the entire thing resulting in even more capacity. 

Mixing it up

The good news doesn’t stop there, you can mix it up and do continuous stockpiling within multiple discrete stockpiles. Why? Because you get a whole lot of flexibility. Want to stack and reclaim in the same pile? Sure! Want to make a stockpile footprint longer while it is being stacked? You got it! Want to shrink a stockpile footprint while it is being reclaimed? Yup, no problem. Got something special coming down the pipe you want to segregate? Bump the stacker down the yard 15 meters and start a new continuous stockpile. Problem solved! 

But what about grade?

So, this all sounds great, but what about grade. To this question I would say, let’s find out! We can model exactly how your grade will change by moving to continuous stockpiles, providing you with videos and graphs of what you shipped during a period compared to what you would have shipped if you were running your yard in a different configuration.   

You may be surprised at the result.

In addition to modelling the change before implementing, we can monitor stockyard tonnages and grade distribution after rollout in near real time, so you can continue to manage your tonnages and grades. 

Want to know more

Give us a call. We’re a one stop shop for these kinds of things. We’ve done studies, control system changes, commissioning, and live monitoring. Always happy to talk stockyards.