SHIELD SILO PROTECTION SYSTEMS - ENSURING SILO SAFETY
Hycontrol's SHIELD SPS Silo Protection System is the most advanced pressure safety system available for powdered product silos. It is the only system that physically tests at ground level all the critical components of your silo protection system before each filling.
Silo protection systems play an essential role in silo safety - preventing the over-pressurisation and over-filling of cement silos, lime silos, flour silos and a wide range of other bulk powder storage silos. Powder silos are typically pneumatically filled from road tankers – compressed air is used to push powder from the tanker into the silo. However, unlike the delivery tankers, which can withstand several bar of pressure, storage silos can be damaged by pressures as low as 1 psi above atmospheric. Silos constructed from concrete can be vulnerable to even lower pressures.
Disasters waiting to happen - how can I prevent silo over-pressurisation and over-filling?
Unfortunately many silo protection systems will not operate effectively when required and are ‘disasters waiting to happen’. The consequences of this can be catastrophic; silos can rupture, pressure relief valves (PRVs) can blow and, in some cases, filter housings on top of the silo can be ejected from their mounts, resulting in injury or even death. In all of these events, product from the silo is released into the environment.
There are a number of reasons for the failure of silo protection systems including poor or inadequate design and little or no regular servicing. In many applications operators ignore warning signs such as product discharge at the top of the silo. If there is powder on top of your silo, there is something wrong with the silo protection system and/or the filters, which can become blocked if not sized correctly or regularly maintained.
Health and Safety Guidelines for Silo Protection
The HSE and MPA (Mineral Products Association) lay down guidelines on the design and maintenance of silo protection systems. Such a system should include a PRV, a pressure sensor, a high level alarm, and an auto-shut off valve to prevent overfilling. Unfortunately even if a well-designed system is installed, unless it is regularly maintained, it may not work as intended if problems arise. If pressure builds up and product is allowed to escape via the PRV, it will solidify in the atmosphere rendering the PRV useless.
Unfortunately, silo protection systems on top of silos are 'out of sight and out of mind', with limited access. The only way to ensure your silo protection system will continue to function is to have a ground level testing (GLT) system which physically tests all the critical components before each and every fill. In parallel, the protection system must be fully inspected on a regular basis. Just visually inspecting the components is of no use at all.
Hycontrol's new SHIELD SPS exceeds current guidance from the MPA and is the most comprehensively-featured, and competitively-priced, system on the market.