Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Laboratory Tests for Selecting Wetting Agents for Coal Dust Control.

Authors
Zeller-HW
Source
MISSING :21 pages
Link
NIOSHTIC No.
10003159
Abstract
The Bureau of Mines is conducting research to determine whether the use of chemical surfactants improves respirable coal dust control and is evaluating laboratory test criteria for selecting effective surfactants. This publication presents the results from wetting effectiveness tests with emphasis on the capillary rise test. The test variables investigated included coal particle size, type of surfactant, surfactant concentration, test duration, and mineral content of the water. In addition to the rise test, measurements of contact angle, zeta potential, and sink time for various coal and surfactant combinations were conducted. No significant correlations among the four wetting tests were observed, a surprising result which implies that each test type measures specific aspects of the wetting phenomenon and also that each test type should only be used to select surfactants for specific applications. For example, the rise test shows solution penetration into porous materials, and the sink test discriminates among surfactants for dispersing finely ground materials into suspension. Another important conclusion is that combinations of agents retain their individual wetting properties, allowing mixtures to be formulated to perform well in both rise and sink tests.
Publication Date
19830101
Document Type
IH; Report of Investigations
Fiscal Year
1983
NTIS Accession No.
NTIS Price
Identifying No.
RI 8815
NIOSH Division
TCRC;
Source Name
MISSING
TOP