Abstract |
A multi-faceted study was conducted to determine the nature of emission problems in the graphic arts and metal decorating industries. By means of field visits and a survey of solvent and ink use, the industry's actual and potential problems were delineated and methods used for solving these were reviewed. An industry sampling plan was developed that will measure and attempt to characterize the emissions, according to the process, type of ink coating and substrate used. Analytical procedures requisite to the chemical evaluation of effluents and sampling technique employed were examined and reviewed. The less complex method of total hydrocarbon analysis suffices for certain segments of the industry. Solvent flow charts for the basic printing processes and modifications thereof were utilized to indicate the process variables in terms of inputs and outputs. Significant emissions can be expected from web printing (letterpress and lithography using heatset inks), metal decorating, gravure and flexography. Control techniques were reviewed and presented. There are three general approaches to the problem of controlling gaseous emissions from the printing and metal decorating industries: the first, the use of air pollution control equipment, the second, a change of process materials and the third is process modification. All were considered from both a technological and economic review. Changes in process material (e.g., solventless or low-solvent inks) were reviewed. Developments in radiative drying were also discussed. (Author) |