Biodegradation of synthetic detergents evaluation by community trials: I. Linear alkylbenzene sulphonates

Abstract

AbstractThe biodegradability of a number of linear alkylbenzene sulfonates (LAS) has been evaluated by field trials with a trickling filter sewage plant serving a small community. All the LAS material examined showed a satisfactory order of biodegradability. In all the LAS materials examined, aeration of the sewage effluent resulted in further biodegradation to a degree corresponding to 96% to 99% degradation of the LAS present in the settled sewage. The results of laboratory scale biodegradation tests are largely in agreement with those obtained in the field trials. However, with tests of the simple open bottle type, such as the test of the U.K. Standing Technical Committee on Synthetic Detergents, misleading indications of low biodegradability may sometimes be obtained on products of higher molecular weight. Such products do not appear to acclimatize sufficiently rapidly to bacteria under the conditions of the open‐bottle test. Under practical sewage treatment conditions, or with tests which simulate these, a high order of biodegradation is obtained. There were only minor differences in biodegradability between an LAS derived from paraffins and those derived from cracked wax olefins.