The Eltek in-vessel compost monitoring system is designed for batch tunnel in-vessel composting systems which can process various materials such as kitchen waste, green waste and organic fines. It is field proven within demanding, corrosive and moist environments.
Eltek data loggers with Eltek GenII transmitters are used to monitor temperature in a large scale composting operation, which enables foodstuffs to be safely composted in compliance with DEFRA (Department of Environment Food and Rural Affairs) Animal By-Products Regulations (ABPR) and matching EU regulation (EU) 142/2011. The customer needed to be able to compost both vegetable matter and animal by-products in this large-scale composting facility and approached Eltek for a solution that would meet regulatory standards and provide records for an audit trail. The solution provided is suitable for use in composting facilities anywhere. A wireless probe version is also available for the "wind rows" method of composting.
Our most recent facility processes food waste, green waste and organic fines, which consist of residue from black bin waste that can pass through a 12mm screen. Aerobic sanitisation is used to produce a compost for brown field site restoration.
The Eltek compost system is designed for (but not limited to) batch tunnel-in-vessel composting systems. The system is approved for use in both PAS100 and Non PAS100 facilities. Typically the vessel is 3m x 3m x 10m long with a retractable roof. Such a vessel can take 100 to 200 tons of feed stock. The batch tunnel-in-vessel composting process can comprise of a two stage pasteurisation process of at least 60°C for a minimum of 48 hours as required under ABPR 2005 / National Standards, or 70°C for 1 hour under the European Standard. Our system works for both standards.
The temperature is monitored using specialist designed stainless steel temperature ('lance') probes inserted into the material at predetermined positions and depths. The probes are connected by long runs of robust cable to the transmitter located outside the vessel. The feed stock is referred to as the batch.
The process is policed by AHVLA veterinarians who will require evidence that the two heat cycles detailed above have been correctly implemented. A total of 8 probes is considered ideal to provide a mean batch temperature of greater than 60°C for 48 hours, However, a mean temperature calculated from 6 probes worth of data is considered sufficient by the vets, providing redundancy in the system should a probe fail.
The process is policed by AHVLA veterinarians who will require evidence that the two heat cycles detailed above have been correctly implemented. A total of 8 probes is considered ideal to provide a mean batch temperature of greater than 60°C for 48 hours, However, a mean temperature calculated from 6 probes worth of data is considered sufficient by the vets, providing redundancy in the system should a probe fail.
This type of system needs to be extremely rugged and reliable, the environment is harsh and with heavy machinery moving large quantities of material around there is no room for delicate equipment. The Eltek system uses heavy duty stainless steel probes, connected to a ruggedized transmitter which sends its data to the more benign office environment where it can be analysed and processed on a desktop computer.
The Eltek system comprises:
Darca Compost has been designed specifically for compost recycling applications. It allows the user to keep track of each batch of compost as it moves between physical storage containers ("Bays"). Batches are grouped either as "Current" (typically less than 6 months old) or as "Historical" for ease of access in the software. The software calculates the results from the two tests each batch must undergo, informing the user whether a batch has passed or failed.
The batch in this example will be referred to as Batch 1.
