Paper Production Plant Research Articles

CHARACTERIZATION OF AIRBORNE DUST IN A SOFT PAPER MILL

The characteristics of airborne dust in a soft paper production plant have been characterized by scanning and transmission electron microscopy. A combination of X-ray diffraction, electron diffraction and energy-dispersive X-ray flouresence spectroscopy (EDX) was used to determine the structure and composition of the different components. Size distribution determination and phase identification were carried out. Besides the cellulose fibres, fibres of kaolinite, wollastonite, talc and other silicates were also identified. Gravimetric analysis and fibre counting by optical phase contrast microscopy were used to determine total dust and fibre concentrations. Total dust exposure at the plant was generally below 3 mg m-3. The respirable fraction of the total dust concentrations varied from 15 to 70%. The inorganic dust was 36 +/- 15% of the total dust. The ratio of inorganic fibres to total fibre concentration at the plant varied between 10 and 15%.

Patterns of Mortality in Pulp and Paper Workers

A proportionate mortality ratio (PMR) analysis utilizing death certificates and work histories was performed on 201 white male decedents who had been employed in pulp and paper production plants and had died between 1970 and 1984. PMRs for all malignant neoplasms (PMR = 131) and lung cancer (PMR = 151) were significantly elevated, whereas PMRs for lymphopoietic system cancer (PMR = 190) and cancer of the large intestine (PMR = 147) showed nonsignificant excesses. Most of the excess cancers of the lung and large intestine were limited to those with greater than 30 years between initial employment in a pulp and paper plant and death. Excess lung and lymphopoietic system cancers have been found in other studies of paperworker mortality, although this study failed to support previous findings of excess stomach cancer. These results continue to raise concerns that paperworkers are at elevated risk for some occupational cancers.

Water Recycling – Industrial Applications

The application of industrial water recycling techniques is demonstrated by examples of various industrial branches such as: steel production, pickling and plating, coal mining and coking, sulphite cellulose and paper production, sugar works, and power plants. Special consideration is given to water recycling in metal finishing works and paper mills.