Fuel Feed Systems

• Brightwater Hog Feed System
• Tachikawa Wood-Waste Handling System
• Pan Pac Forest Products Fuel Handling System
• Hoggers Opening Up New Energy Options In Forestry

Sawmills produce a wide variety of sawmill wood and wood residue. These residues are a valuable energy resource for biomass energy palnts. However, the residues produced are often difficult to handle due to their variable sizes and different moisture contents. Creating automated systems to handle these waste streams and act as fuel feeds requires specialized knowledge and is best tackled on a case by case basis.

Brightwater Engineers have been involved in many New Zealand based projects designing, building, installing and commissioning integrated fuel handling systems. Three example case studies on fuel handling systems are outlined below:

Brightwater Hog Feed System

The Brightwater Hog Feed System was initially designed for Blue Mountain Lumber sawmill in Southland. The sawmill generates significant quantities of green sawdust, wood shavings, and lumber off-cuts which is utilised for a 10MWth steam and electricity co-generation plant.
The site requirement was for a system capable of handling the total range of wood residues and converting them into boiler fuel by passing them through a size-reducing hogger. It was also a requirement to be able to feed these residues into the hogger as either individual streams or as a mixture of different residue types.
Brightwater Engineers designed their Hog Feed unit to handle all material types and to provide a fully automated reception and discharge bunker mechanism.

Follow the following  links to read more:

BANZ project report [PDF 123kb]
Brightwater Engineers project report [PDF 100kb]

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Tachikawa Wood-Waste Handling System

Tachikawa Forest Products has a sawmill located in Rotorua. In 1997 Tachikawa installed a 8 MWth boiler to be fired on wood residues. The majority of the fuel required by the boiler is produced on-site as a by-product of the sawmill process. Additional wood residue required is trucked to the site from other local wood processors.

Brightwater Engineers designed, built, installed and commissioned an integrated fuel handling system to meet Tachikawa’s needs

The following links describe the fuel handling system at Tachikawa in more detail:

BANZ project report [PDF 106kb]
Brightwater Engineers project report [html]

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Pan Pac Forest Products Fuel Handling System

Pan Pac Forest Products, near Napier, have an integrated sawmill and pulp mill. Pan Pac required a fuel handling and management system to store and deliver fuel to a 36 MWth boiler.

The fuel comprises of course green wood residue and dry shavings. The fuels require storing separately but delivering to the boiler in a blended and metered condition according to demand.
Brightwater Engineers designed and built equipment to store and reclaim course wood residue as the primary fuel for the boiler, a shavings handling and storage system to store and discharge shavings to blend with the primary fuel.

The following link describes the fuel handling system at Pan Pac in more detail:

BANZ project report [PDF 89kb]

Brightwater Engineers project report [html]

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Hoggers Opening Up New Energy Options in Forestry

Forestry generates huge quantities of wood residues. Those residues could be a valuable new source of carbon-neutral energy for the industry and New Zealand.

In practice however, using wood residues is difficult in some sectors of the industry, particularly in forests after cutting. Here, the process can end up costing more than using coal.

Machines called ‘hoggers’ have been developed which are specifically designed for processing wood residue from forests.

As part of a new initiative coordinated by the Energy Efficiency and Conservation Authority (EECA), researchers have studied the economics of these machines in New Zealand conditions.

The bottom line is – today’s hoggers are making wood residue a practical and economic energy option in more situations than ever before...more