Storage grain cleaning

Herbicides reduce transportation and storage costs. A good example of the transportation and storage costs of weed seeds was given by a Canadian weed scientist ( 1). He reported that despite herbicide usage and grain-cleaning processes, 33 railroad carloads of weed seeds are transported across Canada from elevators to ports each day. 

In most parts of the world, except India, safflower seed is handled in bulk. In Califomia this is accomplished in large aluminum-sided, bottom-dumping, open-top truck trailers of approximately 10-121 capacity each, two of which are hauled in tandem to a field by a truck tractor unit. The trailers are left by the field to be filled by the farmer, and the tractor unit returns and hauls the full trailers directly to the oil mill or export terminal (in some cases up to 250 km away) or to a closer grain elevator for intermediate storage. In other parts of the United States, safflower is delivered in many types of grain trucking equipment and much of it is delivered to small country elevators where it is stored, cleaned if necessary, and subsequently loaded onto trucks or railroad hopper cars (which can hold between 50 and 701 of safflower seed) for delivery to a buyer. 

Submicron-sized NaCl crystals were deposited on soda lime glass substrates by dissolving a few grains ( 1 mm ) of commercial salt in a drop of de-ionized water on a clean microscope slide. The solution was spread across the slide with a cotton swab and allowed to evqjorate to dryness at ambient humidity and temperature. Both evaporation and sanq>le storage were under ambient laboratory atmosphere conditions—typically 20 0% relative humidity (RH). 

Filtration occurs in depth and the retained particles are deposited in the inter-grain voids which represent around 55% of the bulk volume of the filtering mass. Practically 100 to 110 liters per cubic meter is available for storing retained matter (SS and oils). This useful volume therefore defines the maximum storage capacity. It should never be reached in downflow filtration because the pressure drop would be too great or more importantly, because the quality of the filtrate would decline dramatically. When this capacity is saturated, the filtering mass must be washed in runs by clean water return and blown with blowered air. 

Drying grain and feed to a moisture level of 13%-15% may prevent recontaminatkm during storage. Storage bins and feeders should be kept dry and clean. 

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