The Challenge
A mineral processing facility in Suceava County, northern Romania, mines potash (K₂SO₄) from a local deposit and feeds it into a downstream granulation line. The problem was the moisture at mine output: depending on the season and extraction depth, the potash arrives at 14–22% moisture. The granulation process requires material at 0.3% moisture maximum — anything above that causes caking in the granulator and failures downstream.
The client's existing drying system — a 20-year-old rotary drum unit — could no longer hold consistent moisture output as throughput demands grew. Capacity had been stretched from its original 22 t/h design point to attempted runs at 30 t/h, which put it outside its design envelope. Outlet moisture was drifting to 0.8–1.2% on peak production shifts, causing downstream process interruptions.
The Solution
Lozzar Process specified and delivered a complete drying system sized for 35 t/h at the worst-case inlet moisture of 22%. The complete scope:
— Direct-fired rotary dryer: 2.8 m internal diameter × 22 m cylinder length, constructed in S355 structural steel with abrasion-resistant liner in the inlet zone
— Natural gas combustion chamber: 4.2 MW thermal input, modulating burner with O₂ trim control
— High-efficiency cyclone pre-separator: recovers coarse product fraction before the bag filter, reducing bag filter load and recovering saleable material
— Jetpulse bag filter: 3,200 m² filter area, guaranteed outlet particulate emission <20 mg/Nm³
— PLC-based control panel: inlet temperature and exhaust temperature control loops, bag filter differential pressure monitoring, and data logging with remote SCADA connectivity
The system was manufactured at Ermak Proses in Istanbul, factory acceptance tested, and transported to site by road in two truck loads over 5 days.
Commissioning and Results
Hot commissioning started on a Monday morning with the client's process team on site. By end of day one, the system was running at 34.8 t/h — 99.4% of rated capacity. On day two, with feed moisture deliberately varied between 15% and 20% to stress-test the control loops, outlet moisture held at 0.28–0.35%, consistently within specification. The client signed performance acceptance on day three.
"For a system of this size, three days to sign-off is not common," noted the Lozzar Process commissioning engineer. "The preparation on both sides — our factory testing, and the client's civil and utility readiness — made the difference."
This is the third rotary dryer project Lozzar Process has completed for the mining and minerals sector in Romania, and the first in the potash segment. If you have a mineral drying application in Romania or the wider CEE region, we welcome a technical discussion.