Wood gas: CHP ECO HG

CHP ECO 165 HG with wood gas petrol engine

Burkhardt wood gas CHP ECO 165 HG

CHP ECO 180 HG with wood gas pilot injection gas engine

Burkhardt wood gas CHP ECO 180 HG

165 kWel / 260 kWth*
Engine

This Burkhardt adaptation of the popular MAN D26 pilot injection gas engine of the CHP ECO 180 HG operates without pilot oil. Thus, it is operated on wood gas alone and is even easier to service. The pilot oil unit was removed. Instead, the wood gas-air mixture is ignited with spark plugs. The Burkhardt ECO 165 HG, together with the Burkhardt V 3.90 wood gasifier, generates about 165 kW electrical and about 260 kW thermal energy and has a pellet consumption rate of 110kg/h.

 

PRINCIPLE OF THE PETROL ENGINE

Our engine operates on the currently predominant internal combustion principle known as lean burning. Lean burning means that the gas-air mixture is burned with an air ratio of ʎ ≥ 1.6. With lean burning, the exhaust-gas emission limits according to the German TA Luft can be achieved with engine-based measures. The compressed homogeneous wood gas-air-mixture can and should not self-ignite in a petrol engine. For this reason, the mixture is ignited in a controlled way with electrode spark plugs. In order to operate the motor in the best possible efficiency range at any time, and at the same time protect the mechanical components of the engine, an active knock control is used here. The knock control monitors the combustion sequence (combustion noise) and, if necessary, influences the ignition time.

180 kWel / 270 kWth*
Engine

The basic engine is a MAN D26 six-cylinder in-line diesel engine with turbocharger, control unit, and 4-stroke common rail fuel injection system, as well as 4-valve technology with optimised combustion chamber and centrally arranged injection elements. The Burkhardt CHP ECO 180 HG, together with the Burkhardt V 3.90 wood gasifier, generates about 180 kW electrical and about 270 kW thermal energy and has a pellet consumption rate of 110kg/h and 4 l of pilot oil / h.

 

FUNCTIONAL PRINCIPLE OF A PILOT INJECTION GAS ENGINE

In a compression-ignition engine (diesel functional principle), the wood-gas/air mixture is not ignitable. In order to be able to benefit from the good efficiency of the diesel engine compared to the petrol engine, pilot oil is injected. This results in a fuel/air mixture in the cylinder which is self-igniting when combined with sufficient compression. Using the common rail injection process (CDI), the combustion can be controlled in such a way that the efficiency level can be further optimised. A rape seed oil raffinate is used as pilot oil. Heating oil or diesel fuel are also suitable. However, the country-specific requirements must be taken into account. The additional consumption of pilot oil contributes fully to the engine output.

GENERATOR

An air-cooled synchronous generator is used in both models. The generator has the type of protection IP 23. It is equipped with a double-mounted rotor in order to keep the bearing loads on the drive unit as low as possible. The brushless AREP system by Leroy-Somer is used as field excitation system. The spacious and expandable terminal box enables simple access for maintenance and installation tasks. Housings made of steel, end shields made of grey cast iron, and lifetime-lubricated bearings designed for the special requirements and the vibrational behaviour of the drive unit.

BENEFITS OF THE PETROL ENGINE
  • NO pilot oil needed
  • Tried-and-tested base engine (MAN D26, Burkhardt adaptation)
  • No complex pilot oil unit with pilot oil tank needed
  • Easier to maintain
  • Possible advantages when it comes to authorisation
  • Fewer emissions
ADVANTAGES OF THE PILOT INJECTION GAS ENGINE
  • Tried-and-tested base engine (MAN D26)
  • Intelligent control system
  • Robust combustion (very high ignition energy)
  • Security of supply with liquid fuel (emergency operation possible even without wood gas)

 

* Thermal output incl. exhaust heat of the wood gasifier