Search

The use of nitrogen gas in grain storage has a history of over 30 years. However, it wasn't until the recent emergence of economically efficient pressure swing adsorption (PSA) and membrane separation (MS) nitrogen production equipment that this technology became viable for grain storage. This study first conducted laboratory bioassays over 4, 3, and 2 weeks on wheat, barley, oats, lupin, and canola seeds, exposing them to environments of 25 ℃, 30 ℃, and 35 ℃ with nitrogen concentrations of 99%, 98%, and 97%. The study focused on assessing the adult and immature stages of Trogoderma variabile, Tribolium castaneum, Rhyzopertha dominica, and Sitophilus oryzae. Subsequently, in-field verification was carried out at the Lake Grace terminal and the Cooperative Bulk Handling (CBH) grain export terminal in Albany, evaluating the efficacy of controlling various storage grain pests and field pests in wheat, barley, and canola seeds, as well as assessing the quality of treated grains. The results showed that pest mortality increased with decreasing oxygen concentration, increasing exposure time, and temperature. However, under low-temperature conditions, nitrogen-rich low-oxygen treatment did not achieve 100% mortality of Trogoderma variabile larvae. There was no significant difference in the efficacy of controlling storage pests resistant or sensitive to phosphine. Canola seeds showed better control efficacy compared to other grains. Furthermore, the moisture content, protein, oil content, starch, and grain color quality indicators of various grains were unaffected. A commercially scalable nitrogen-rich low-oxygen application model was successfully developed, providing a solution for controlling pests resistant to phosphine and meeting the growing market demand for insect-free and chemical residue-free grains.

Nitrogen technology has been developed as a complementary technology with fumigants, for control of key pests in Australian grain storages. However, market feedback from industry was its cost which remained as a barrier of uptake. Therefore, a commercial scale trial was set up using advanced membrane technology to assist industry overcome operational and the cost barriers for the uptake of the technology. A new generation membrane technology was sourced from Changshun Anda, a China-based company. The unit was deployed at the CBH grain port of Kwinana, Western Australia to compare performance against an older nitrogen generation technology (Pressure Swing Absorbance/PSA). To meet the strict Australian standards operating conditions the port the unit was upgraded by Changshun Anda specialist team. The target benchmark was set to $0.50 per tonne of grain (the high-end cost of a phosphine fumigation). Research demonstrated an operational cost for the older PSA technology of $2.43 per tonne of grain. The technology also displayed operational limitations in its ability to generate and maintain the required level of nitrogen purity necessary to provide insect control (99%). In comparison, the generation of nitrogen using membrane technology cost $0.99 per tonne of grain. Other performance gains were generation of required nitrogen purity within 4.5 days of operation and ability to maintain purity for the required 14 days to provide full control of pests.

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)