NEO MAKİNA ve MÜHENDİSLİK A.Ş. designs and manufactures industrial travelling (chain) grate combustion systems for continuous, automatic firing of coal, biomass and agricultural residues. A low-maintenance, high-efficiency solid-fuel solution for steam boilers, thermal oil heaters, hot-air generators and dryers.
What Is a Travelling Grate Combustion System?
On a travelling (chain or belt) grate, fuel is carried through the furnace at a controlled speed on a moving grate surface. It passes through drying, devolatilisation, main combustion and ash-cooling zones in turn; when combustion is complete, ash is discharged automatically at the grate end. Grate speed and air distribution are adjusted to the fuel's calorific value and moisture.
Operating Principle
- Fuel dosing: Fuel taken from the main bunker by screw conveyor is weighed in a load-cell day bunker and fed to the grate.
- Even spreading: Vibrating or pneumatic spreader distributes fuel evenly across the grate width; no hot spots or unburned zones.
- Variable-speed drive: Planetary gear motor with inverter control; grate speed adjusts automatically to load.
- Staged air: Primary air is supplied zone by zone from under the grate; secondary air enters from the furnace side walls to create turbulence.
System Components
Grate and Cooling
- Grate bars: Alloy cast steel resistant to high-temperature corrosion and thermal shock.
- Cooling: Air-cooled for low-medium capacity; water-cooled grate for high capacity and fuels with low ash-melting temperature.
Furnace
- Refractory: Furnace lined with high-temperature refractory brick/castable for low heat loss.
- Ash discharge: Wet or dry automatic ash conveyor.
Automation and Emissions
- PLC/SCADA: Fuel feed, grate speed, fans and O₂ trim controlled from one panel; remote monitoring.
- Flue-gas cleaning: Multicyclone and bag filter for dust; additional SO₂/NOx units where required.
Typical Application Range
- Thermal capacity: 1 – 30 MW (single grate); higher with multiple grates
- Fuel: lignite, hard coal, wood chips, pellets, hazelnut and walnut shells, olive pomace, corn cobs, other agricultural residues
- Fuel size: 5 – 50 mm; moisture up to 40%
- Applications: steam and thermal oil boilers, district heating, greenhouse heating, industrial dryers
- Design codes: EN 12952/12953, CE
Operating Advantages
- Continuous automatic operation with minimal operator intervention.
- Wide fuel and particle-size tolerance.
- Low maintenance: worn grate bars are replaced individually.
- Low CO and NOx through staged air; low unburned carbon in ash.
The NEO MAKİNA Difference
Grate size, air zoning and furnace geometry are calculated from fuel analysis. Retrofit applications and grate modernisation for existing boilers are carried out. Installation, commissioning and operator training are included.
Frequently Asked Questions
What is the difference between a travelling grate and a reciprocating grate?
A travelling grate gives continuous flow with homogeneous, small-sized fuels (coal, pellets, chips). A reciprocating grate suits coarse, wet and heterogeneous fuels (wood, RDF, sludge).
What fuel moisture is acceptable?
Fuels up to 40% moisture can be fired using the pre-drying zone and hot primary air; a drying unit is recommended for higher moisture.
Can a travelling grate be added to my existing boiler?
Yes. If furnace dimensions are suitable, the grate, feeding group and fans are retrofitted; a feasibility study is prepared at proposal stage.
To select the right travelling grate system for your fuel and request a quotation, contact us.