MULTI JET fuels

Heating oil made from crude oil is divided into two types: light heating oil (heating oil EL) and heavy heating oil (heating oil S). The quality requirements for heating oil are defined in DIN 51603. Light heating oil can be burned in furnaces, central heating systems and industrial firing plants without preheating. Heavy heating oil, on the other hand, has to be preheated for transport and burning. The systems running on these fossil fuels, however, are increasingly subject to regulations and restrictions.

The BENNINGHOVEN gas burners can burn liquid gas already during the liquid phase, without first having to transform it into a gaseous state. This means that no additional periphery such as an evaporator is necessary and therefore no additional energy is required either.

Liquid gas burners and natural gas burners have the same mechanical structure. They differ only in their periphery, i.e. how the fuel is introduced into the burners.

Liquid gas, referred to as “associated gas”, is generated during the extraction of crude oil or natural gas. This associated gas used to be simply released into the atmosphere or burned in many cases. Today, more and more regions worldwide have banned this burning, which has an additional positive impact on the increasing availability of liquid gas.

Wood is a renewable resource which can be produced sustainably and is therefore carbon-neutral when used as a fuel. With the MULTI JET wood dust burner, BENNINGHOVEN has made it possible to burn wood dust in asphalt mixing plants, adding another product to the portfolio of burner technologies developed in-house. The wood dust burner offers owners a sustainable option for modernising their existing mixing plants.

The development engineers at BENNINGHOVEN have identified the ideal particle size of the wood dust, which is produced mainly from scrap wood and wood waste. Identifying the optimum grading curve for the fuel is important for the flame geometry of the burner – and therefore for the effectiveness of heating the virgin mineral or the recycled asphalt (RAP). Several Benninghoven customers are already successfully using the MULTI JET wood dust burner.

The complete periphery includes the burner and the dosing unit. The interface to the customer systems is the inlet to the dosing unit. The wood crusher and the wood silo are provided by the customer.

Burner
The wood dust is fed into the burner with precision dosing by means of the feed fan and the dosing unit. In the burner head, a separate auxiliary flame then ignites the material. The control range for wood dust with pilot flame is 1:6; the calorific value of wood dust is approx. 18 MJ/kg depending on the type of wood.

The secondary fuel, e.g. heating oil EL, liquid gas or natural gas, is used for the support flame.

The owner is obligated to ensure that the overall plant (for example the silo with the dosing system) is checked as part of a regular inspection as per the German industrial safety regulations (BetrSichV). Outside of Germany, the systems are subject to mandatory testing – the applicable national laws and directives must be observed.

Explosion protection (ATEX) especially for coal dust and wood dust

The principle of producing biomass-to-liquid (BtL) fuels is based on liquefying biomass.

In the case of wood as a starting material, thermo-chemical conversion processes in a reactor use high temperature and high pressure to turn the cellulose-rich wood into pyrolysis oil.

The further processing steps are cleaning, synthesis and refining of the pyrolysis oil to produce BtL fuels.

For wood or wood waste as a starting product, the challenge lies in the processing of the natural material that can vary greatly in its chemical composition. These fluctuations affect the final BtL product. Smaller fluctuations can be compensated by adapting the preheating temperature. Larger fluctuations or fuel changes, however, require adjustments on site.

Customers therefore send their heating medium to Wittlich in a stainless steel container so the correct basic parameters for the burner can be determined at the BENNINGHOVENBENNINGHOVEN factory for new fuels. There, the fuel is tested extensively and the optimum burner settings are identified.

• BENNINGHOVEN MULTI JET brenner – attached to the dryer drum
• Coal dust is fed into the burner with precision dosing using the supply fan and coal dust dosing system.
• In the burner head, a separate auxiliary flame then ignites the material.
• This is switched off at a burner output of 20 % of the nominal burner output.
• The solid material flame continues to burn independently from this point onwards or is automatically activated again when the value falls below the set value.
• The fuel for the ignition flame can also be used as an independent fuel.
• Control range 1:5 for coal dust only and 1:8 for coal dust with auxiliary flame
• Calorific value of coal dust 20,900 kJ/m³
• Burner control, output control, coupled control and switchover between the fuels are implemented with a type-approved control system.

Asphalt production, recycling systems, combustion technology, control systems and bitumen technology – with BENNINGHOVEN technologies, every customer can find the right solution for their location, according to the specific requirements and conditions.