Evaluation of innovative low-volatile organic compound (VOC) industrial maintenance (IM) coatings. Report for April-September 1994
The paper discusses a field evaluation of the feasibility of using alternative low-volatile organic compound (VOC) coatings to replace higher-VOC coatings. The evaluation includes chemical, performance, and outdoor exposure testing. The feasibility of five alternative coatings for reducing pollution is considered. The coatings are compared to a standard coating that is being used in practice. Although outdoor exposure testing is not yet complete, available results indicate that all of the coatings have characteristics that could make them viable alternatives. For VOC emissions reduction, coating 4 (a two-component polysiloxane epoxy) was the best.
Pollution prevention methods in the surface coating industry
Abstract The surface coating industry is rapidly changing to meet environmental and economic pressures. Some of the changes include new formulations which meet environmental regulations, higher performance finishes with improved properties, continued development of solventless technologies such as powder coatings and radiation curable coatings, and new application methods with improved transfer efficiencies. These changes will be accelerated by the 1990 amendments to the U.S. Clean Air Act. These new enviromnental laws will require industry through the Environmental Protection Agency (EPA) and state and local agencies to further reduce emissions of volatile organic compounds (VOCs) which are contributors to ozone formation in the lower atmosphere. The focus of this paper will be to examine the paints and coatings industry and those pollution prevention methods that are being applied to meet these environmental pressures. It will review the life cycle of paints and coatings; from its inception in the manufacturing facility to its ultimate application and disposal. It will also review developing low VOC technologies that are being considered worldwide to comply with increasing VOC regulations.
Increasing pulp yield in kraft cooking of softwoods by high initial effective alkali concentration (HIEAC) during impregnation leading to decreasing secondary peeling of cellulose
Abstract Pulp yield can be improved by a more homogeneous delignification of the chips, achieved by improved impregnation prior to the cooking stage. Complete and efficient impregnation is obtained by increasing the diffusion rate by means of an impregnation liquor with a high initial effective alkali concentration (HIEAC). In the present study, the effect of HIEAC in the impregnation was evaluated and compared to a reference impregnation procedure and a prolonged impregnation. After the various impregnation scenarios, the alkali concentration was always adjusted to the same level in the beginning of the cooking stage. Impregnation with a HIEAC resulted in yield improvements by 1–1.5% units, due to a higher cellulose yield and possibly also to higher yield of glucomannan. The HIEAC with an even alkali distribution within the chips prior to the cooking stage resulted in a more uniform delignification carbohydrate degradation. Yield increase obtained by uniform delignification is due to both decreased shives content as well as less secondary peeling.