SRF Dryer Manufacturer
See how we dry SRFIf you are shortlisting SRF dryers manufacturers or solid recovered fuel drying plant manufacturers, STRONGA designs FlowDrya lines that condition SRF into a consistent, cement-kiln-ready fuel. As an alternative fuel dryer manufacturer, we build each plant to order at our Hertfordshire works, matched to your fuel spec and heat source.
- FlowDrya continuous flow drying range — in production since 2012
- Engineered and built to order in the United Kingdom
- Custom-configured to your material, throughput and heat source
FlowDrya SRF (solid recovered fuel) dryers are manufactured by STRONGA LTD, built to order in the UK as part of the FlowDrya continuous flow drying range, in production since 2012.
FlowDrya conditions SRF down to below 15% moisture – the specification cement plants require for stable combustion – raising net calorific value from around 12–13 MJ/kg at 35% moisture to 18–20 MJ/kg at 15% moisture.
Why SRF Needs Drying
Moisture is the primary factor limiting the energy output of Solid Recovered Fuel (SRF): moisture content above 15% reduces net calorific value because combustion energy is consumed evaporating water. SRF often carries significant surface moisture even though its plastic content has low bound water compared with RDF, and ambient conditions cause seasonal fluctuations in incoming moisture. Flow drying stabilises SRF quality year-round, so calorific value and combustion performance stay predictable batch after batch.
How a FlowDrya SRF Drying Plant Works
FlowDrya SRF dryers use existing residual heat sources common at cement plants – waste heat from clinker beds, kilns and pre-calciners. The deep-bed drying floor (600–800mm) is designed specifically for light, fluffy SRF, with PulseWave™ agitation continuously mixing and tumbling the material so every part of the load receives equal thermal contact and airflow. A stainless-steel drying floor gives a service life of 25+ years, and the stop/start hydraulic operation uses 3–4X less electrical power than belt dryers.
SRF Moisture, Calorific Value & Cement Kiln Specification
Under EN ISO 21640, SRF is graded into five classes by net calorific value: Class 1 (≥25 MJ/kg, <5% moisture) down to Class 5 (≥3 MJ/kg). As moisture falls from 35% to 15%, calorific value rises from around 12–13 MJ/kg to 18–20 MJ/kg – the specification most cement kilns require. Dried below 10%, loose SRF can also be compressed into pellets, increasing bulk density by up to 9X and improving handling, storage and combustion stability.
SRF Moisture Content vs Calorific Value
| Moisture Content | Approx. Calorific Value |
|---|---|
| 35% | 12–13 MJ/kg |
| 25% | 14–16 MJ/kg |
| 15% (cement kiln requirement) | 18–20 MJ/kg |
| 10% (pellet requirement) | 19–22 MJ/kg |
SRF Dryer Manufacturer FAQs
Who manufactures SRF dryers?
FlowDrya SRF dryers are manufactured by STRONGA LTD (Companies House 03974884), engineered to order in the UK. The FlowDrya product line has been in production since 2012.
How does a FlowDrya SRF drying plant work?
FlowDrya SRF dryers use residual kiln, pre-calciner and clinker waste heat, drying material on a deep bed (600–800mm) with PulseWave™ agitation. A stainless-steel drying floor gives a 25+ year service life, and the stop/start operation uses 3–4X less electrical power than belt dryers.
What moisture content do cement plants require for SRF?
Moisture content above 15% reduces SRF's net calorific value, so FlowDrya SRF dryers ensure consistent SRF quality via optimised moisture removal to below 15% moisture, the specification most cement kilns require.
Can dry SRF be used for pellet production?
Yes. Dry, loose-shredded SRF below 10% moisture content can be compressed into high-value, dense SRF pellets, increasing bulk density by up to 9X and improving functionality, handling and calorific stability.
What are the SRF classes under EN ISO 21640?
EN ISO 21640 grades SRF into five classes by mean net calorific value: Class 1 ≥25 MJ/kg (<5% moisture), Class 2 ≥20 MJ/kg (<15%), Class 3 ≥15 MJ/kg (<40%), Class 4 ≥10 MJ/kg (<55%), and Class 5 ≥3 MJ/kg.
What heat sources can supply a FlowDrya SRF dryer?
FlowDrya SRF dryers utilise spare kiln heat, pre-calciner waste heat and clinker waste heat commonly available at cement plants for energy-conservative drying of SRF.
Do you install and commission SRF drying plants?
Yes. Every FlowDrya is fully assembled and factory-tested at Stronga's works before being disassembled for shipping. On-site installation is typically completed within days, followed by commissioning, operator training and a full 'hot test' before handover.