academic press alcohol aspen bod bark biochemical oxygen demand biodiversity birch black liquor bleaching of wood pulp brittle books program calcium bisulfite canada cellulose chelation chlorate chlorine chlorine dioxide counter ion doc de-inked pulp digester dissolved organic carbon eucalyptus fiber crop finland fir forest management fungus germany greenpeace grindstone hardwood hydrogen peroxide kraft process larch linen logging magnesium nbsk natural environment newsprint old growth forest oxygen ozone pgw ph paper paper mill paper pulp paper recycling paperboard pine polychlorinated dibenzodioxins pulp mill pulpwood rmp recovery boiler reforestation sapwood silicon carbide sodium carbonate sodium dithionite sodium hydroxide sodium sulfate sodium sulfite softwood spruce sulfite process sulfurous acid sustainability sweden tmp toilet paper tsuga white paper wood wood-pulp paper woodchipping