Malt conveyance:
For transportation of grains like Barley and Malt there are a variety of different systems available. Each of them has advantages and disadvantages and need to be considered carefully according to budget and the task at hand.
Common Methods
Flex Augers: This is a very versatile, the least expensive option, and widely used method. These can convey horizontally and at up to 60 degree incline. Rates and overall length limitations are adequate for most breweries. Properly designed and installed systems cause minimal breakage and provide acceptable service life.
Bucket Elevators: These are used for vertical transportation where minimal horizontal distance is available. Infeed, discharge, flow should be carefully reviewed to ensure good service life. Most layouts require horizontal conveying at infeed and/or discharge.
Enclosed Tubular Drag Conveyor: These are very versatile enclosed conveying systems for horizontal and vertical in a single system. These are extremely gentle on grain and can handle multiple inlets and considerable distances easily. Disadvantage would be the installation cost and initial cost when compared to a flex auger.
Flex augers, bucket elevators, and tubular drag systems do not completely empty so it’s critical to stage specialty malts in the middle of the batch and to flush the system with base malts. These systems are all sealed during installation and result in minimal dust.
Pneumatic Conveying: Pneumatic conveying uses air in an enclosed system and can be vacuum or pressure. Like a tubular drag system these can convey horizontal, vertical, handle multiple inlets, discharges, and significant distances. These are the most sanitary option and experience near full cleanout.
Screw Conveyors (Augers): Screw conveyors can be used in various applications in the brewing and malting industry.
In-feed and discharge can be located at any position along the conveyor. Usually in-feed and discharge are set at either end of a screw conveyor to ensure proper emptying of the screw. The transportation can be horizontal or up to 60 degree incline. The goods (malt) get mixed during transportation. Screw conveyors can be used for unloading of Silos, loading of trucks, railroad cars, spent grain removal and much more.
The disadvantages are the high-energy consumption, (not that high really) development of dust, and it cannot be used for long distance transportation jobs. They require some maintenance and typically cannot get emptied completely (at least it’s not easily done). Screw conveyors are used for short distance transportation. Auger conveyers do tend to “beat the grain up” somewhat and depending on the length of transport, the mill may need to be adjusted to compensate for the breakage.
Trough Chain Conveyors: A very popular and versatile conveying system, widely used in the malting and also brewing industry mostly for horizontal conveying but can also handle incline of up to 30%. Intake and discharge of goods is possible at various locations, the goods do not get mixed during transportation in general but there is some mechanical friction. A disadvantage is the noise and also the usage of the through chain paddles.
There are a few other systems in use but the systems mentioned above are most common.