Forestry

Waste was one of the first considerations for Southern Pine Products when it started manufacturing MDF (medium density fibreboard) products.

The company opted to install a briquette press, which turns MDF dust into combustible briquettes for boiler fuel.

Moffatts Flower Company, a greenhouse complex only 5 km from Southern Pine, now buys all the briquettes the company produces.

The saving in Southern Pine's waste disposal costs is projected to be $180,000 a year and annual revenue from briquettes is projected to be around $25,000.

Fitting a variable-speed drive to a fan motor for a boiler has already saved Juken Nissho's Wairarapa mill $20,000 on a $50,000 investment made a year ago.

This Technical Guide provides guidance on the conversion of existing coal fired boilers to wood pellet operation. There are a number of obvious advantages to using wood pellets: they are 100% renewable and relatively clean burning. Of paramount importance in a conversion is the need both to maintain the safety and integrity of the boiler and control systems, and also to improve safety to the level of best practice.

A thermal energy audit of South Island MDF producer Dongwha Patinna identified seven energy management opportunities, and a buyer for excess fuel produced onsite - which together could be worth up to $288,000 a year.