On-farm Product Dehydration, Storage and Hulling One of the highlights from the trip was a visit to Mark and Fred Montgomery of Chico. They are a family operation, farming approximately 700 acres of almonds, 300 acres of walnuts, and have their own dehydration and hulling (in- shell) facilities. Montgomery’s and the area of Chico, walnuts, a significant crop in this region. Montgomery’s planned to install their hulling facility in at least two stages, with the aim of expanding as their orchard production increased. However, the first stage has only been installed and the second won’t be required due to the highly efficient output being achieved, with the success attributed to the dehydration process prior to hulling. The dehydration was conducted by two methods: Batch Drying This system involved small trailers with false bottom floors, a connection for heated air to be blown in the bottom of the trailer and up through the trailers, recaptured near the roof of the shed via a plenum and blown back through the trailers again. The trailers are only 2/3 filled with product to enable quick drying, and only used for emergencies when the product became very wet from rain. Very wet product (e.g. >20%) would take approximately 24 hours to dry using this process. Bulk Drying This facility was more elaborate than the trailers, but at the same time was also very simple and very effective. The bulk drying facility was installed with the same objective of only using it to dry larger volumes of product with kernel moisture levels of approximately 12-14%; however, it produced such a significant increase in through-put of hulled (in-shell) product, it is used every season regardless of the climatic conditions. The bulk drying facility consisted of: • Pre-cleaner to remove foreign material from the harvested product. This was considered a critical component in efficient drying times. • A partially insulated shed in which are familiar with product drying due to the wetter climate and the mandatory requirement of drying
exchange unit located at the base of each silo. • A fan located below each of the silos to suck air heated through the radiator, and pushed up through each silo. The first cycle of air had the option of being expelled to atmosphere (outside the shed) and disposing of the moisture laden air. Subsequent cycles of dry air were re-circulated through the silos by closing the vent to atmosphere.
R&D Roundup Ben Brown continued from page 17
The machine was originally developed for their family almond orchards due to the time and cost involved in harvesting with the traditional inverted umbrella method. A total of five machines have been manufactured. The almond orchard needs to be developed specifically for the Tenias to obtain maximum efficiency, including precise row straightness, minimum row width of 5.5m, minimum tree spacing of 3.0m, maximum tree height of 4.5m, and a minimum trunk height of 1.0m. The harvesting speed is approximately 2km/ hr or 5-6 trees/min, and crop removal is approximately 50 tonnes of in-shell product/day. The on-machine storage of harvested product is approximately 2m3 per hopper or 550kg/in-shell per hopper. The current speed of the machine is limited due to the time taken to de-hull the product. The de-hulling feature is most successful when the kernel moisture is equivalent to 12% or less. The harvested product stored in the hoppers is unloaded at the end of the row by tipping it into the bucket of a front end loader and then emptied into a truck. The key features were the continuous movement of the shaking head without the stopping and starting, and the in-orchard de-hulling of the hard shell varieties. The dimensions of the Tenias make it suitable for younger (e.g. <5 years old) Australian trees or higher density plantings with potentially smaller trees; however, the higher Australian yields could limit the machines performance, in particular there is a lack of on- machine storage for harvested fruit and inappropriate unloading and logistics. The storage, unloading and logistics could be easily modified and Tenias indicated they were willing to work on the development of the machine for Australian conditions.
• Temperature monitoring with a drying threshold of 54°c. This was not to be exceeded at the top of the silo. Commonly, 52°c at the top of the silo was the temperature at which drying was ceased. • A cooling chamber which consisted of a vented hopper and fan. Once dried, the product was conveyed into the other side of the shed, away Top to Bottom: Montgomery’s batch driers: Drying trailers, Heating unit and plenum, connecting shoot to false bottom floors and Drying trailer with false bottom floor.
eight silos (2 rows of 4) storing 15 tonnes each (120 tonnes total).
• An outside central boiler. • Radiators acting as the heat
Over-the-row, continuous harvester developed in Spain