Sealing grain stores for quality control
If you’re looking for the highest standards in pest control in your stored grain, the solution is simple; an Optimum Sealed Silo. Our custom designed Optimum Seal gives you the assurance you need as a grower that your stored grain will maintain a high quality. Our system does this by integrated pest management; hygiene, aeration and sealing all to the highest industry standards. Sealing ensures that the right concentration of pesticide is present through the whole silo for the right amount of time, leading to a significantly lower risk of a resistant population developing in your store grain.
Why do I need to seal my grain storage?
It’s important that pests in your grain are controlled, as they can cause significant damage to the quality of your grain. Pest contaminated grain has the potential for an entire silo load to be damaged and downgraded; so the importance of investing in a sealed storage system is obvious.
After a high standard of hygiene and high-quality aeration matched correctly to the silo and grains stored, sealing allows IPM to be effetely achieved. To reduce the potential of insect resistance to fumigants and insecticides, a sealed silo allows even and accurate dosage to occur.
Even if the grain is planned to be feed grain, you can still lose out economically with grain that is protein deficient thanks to pests in your stores.
Fumigation and pest control (silos over 300 tonnes)
To be able to effectively kill grain pests at any stage of their life cycle, phosphine gas levels need to be maintained at a level of up to 1200ppm, and over 400ppm, for 20 days through-out the whole silo. This becomes possible in a gas-tight storage bin with a recirculation system.
Being able to fumigate your grain is a much cheaper and far more effective means of controlling insects, which will also avoid residue and reinfestation problems; but it is only step one in the process. Effective sealing, followed by routine maintenance to ensure gas-tightness is a must.
What about moisture and mould?
Current research and anecdotal experience in Australian climates suggest that moisture and mould should not be a problem when the grain is stored at or below its safe moisture (this will differ for all grains). Problems will only arise in a sealed silo should moisture levels be too high, or insect infestation occur, as both will cause an increase in temperature and the subsequent development of moisture.
This scenario of course can lead to mass spoiling throughout the store brought on by wetting of the grain surface. However when an appropriate moisture level and grain temperature is achieved through cooling and drying prior to sealing, the sealable storage system will work to reduce any such issues arising.
Testing for gas-tightness
A sealed silo needs to be monitored regularly during fumigation to ensure its gas-tightness is maintained. Seasonal maintenance is required on all penteration points on a sealed silo. Testing is based on a standard test developed by the CSIRO, and essentially pressurises the silo to 1 inch water gauge. The silo should maintain up to 0.5 inch water gauge for 5 minutes when new, and 3 minutes when filled with grain.
At Optimum Silos we test all of our sealed silos in accordance to AS2628.
Sealing during design VS retro-sealing
Strict gas-tightness standards exist for grain storage systems nationwide; with many growers choosing to retro-seal their stores over the past two decades. Ideally, sealing is planned and achieved during the design and consultation phase, as retro-fitting a seal can be expensive and uneconomical for the grower.
With Australian climate conditions as they are, stores are extremely conducive to moisture and pests, which is why we work with Australian made Cyclone Silos that are designed and manufactured with Aussie conditions and the Aussie grain grower’s best interests in mind. The Cyclone silo range now has the highest structural rating on silos with a 1 in 200year wind event rating. This engineering also means that the silo is designed to be a sealed vessel. The roof and walls are designed to take the extra pressure (both positive and negative) a sealed silo creates.
This allows Optimum to build the Cyclone Silos to be sealed year after year, allowing our clients to make a robust capital investment designed to last generations.
Our team will work closely with you to determine the best storage solution for your grain in your location, and ensure that you’re getting the best return on your investment.
In simple terms, what an investment in sealing your grain will give you is peace of mind for your livelihood. While management and monitoring of grain stores remains important, sealing your silos is a big step towards mitigating the risks of damage to your stores.