Field Trial to Assess Ash Leachability and Gaseous Emissions from Boilers Firing Deinking Residue, 1995 Engineering Conference Proceedings

Honghi Tran, Jouko Latva-Sommpi and David Barham

The Pulp & Paper Centre and

University of Toronto

Richard McMullen

Avenor Inc.

Mark A. Douglas

ABB Combustion Division

A field trial was performed to examine the chemistry and leachability of ash and gaseous emissions from boilers burning deinking residue with natural gas and bark. The results show that for the boiler firing deinking residue with natural gas, increasing the combustion temperature by increasing the gas flow rate had little effect on NOx emissions and ash chemistry. Fly ash consisted of mostly calcined clay, CaO and TiO2 Bottom ash was similar but had higher SiO2 ,Fe2 O3 Na2 O, K2 O and PbO contents than fly ash. Pb originated likely from clay used as a coating material. Hg was enriched in fly ash and particulates, but its concentration was too small to be of concern. The leachability of both bottom ash and fly ash was low, particularly for boilers which burn deinking residue with bark due to the high CaO content.