Many of us may know what a silo is, those huge structures that can often be spotted on the skyline in farming and agricultural areas, where they are used for storing bulk commodities such as grain. From breakfast cereals, to bread, pasta, and even spirits like gin and whiskey, grains such as wheat, barley, maize, rye and oats are widely grown, harvested and used in the production of food, alcohol and animal feed. You may give little thought to silos and their role in our everyday lives, but it is an important one.
The UK harvest season is witnessing a jump start this year with a nationwide heatwave, and silos will have a vital role to play in protecting these commodities within a stable environment that reduces the risk of spoilage from contamination. As part of this process it is vital to keep silos properly cleaned and maintained. Regular cleaning of silos prevents the build-up of product residues on internal surfaces, which can create the ideal conditions for microbial growth, which could in turn lead to the spoilage of stored commodities or worse still contamination.
As silos are very large and often dangerous structures, cleaning them is not a simple process. Although the techniques used to clean a silo are straightforward, actually completing the job is far from it and specialist cleaning teams that are fully trained in confined space entry, emergency escape, and the correct use of appropriate equipment need to be engaged.
The health and safety of cleaning operatives is paramount when cleaning silos, as there is a high risk of injury or fatality if suitable equipment and procedures are not in place. Ensuring the use of the correct safety equipment is crucial, especially when working with dusty food stuffs such as flour, as the potential for a spark from electrical equipment to ignite dust and cause an explosion, is a very real possibility. Furthermore, the cleaning process can also result in a large quantity of dust, which can increase the cleaners’ risk of lung conditions and therefore particle masks are essential for anyone conducting a silo clean.
When cleaning a silo a team of three is standard. First, an entry technician is typically winched into the main chamber and supported by a winch-person. A third person is then on hand to record gas readings and assist in case of an emergency. The air must always be tested with a gas detector before entering the silo, as it may be oxygen deficient and dangerous to enter.
Once specialist operatives are safely in the right place, the actual process of cleaning the silo is relatively straightforward, the same as cleaning any large storage area. It involves dry brushing, scraping and the removal of waste. The only real challenge is the difficulties presented by the specific commodity. For example, sugar can set like concrete, and flour is prone to clinging onto the side of the silo creating a thick layer of flour suspended in mid-air, which can bridge across the silo and then empty beneath.
So, next time that you tuck into your breakfast cereal or relax with a ‘dram’ of whiskey, then maybe spare a thought for the mighty silo and the important role it plays in storing and protecting our grain.