Surface-active agents in waste waters. IV. Biological degradation of nonionic agents in laboratory models of aeration tanks
Pitter, P; Trauc, J
| HERO ID | 4944628 |
|---|---|
| In Press | No |
| Year | 1963 |
| Title | Surface-active agents in waste waters. IV. Biological degradation of nonionic agents in laboratory models of aeration tanks |
| Authors | Pitter, P; Trauc, J |
| Volume | 7 (1963) |
| Page Numbers | 201-216 |
| Abstract | Investigations are reported, with tabulated and graphical results, using a model activated-sludge tank to study the biological degradation of non-ionic detergents based on alkylene oxides. In contrast to the results previously obtained with Dubaral, a biologically-hard alkylbenzenesulphonate (see Wat. Pollut. Abstr., 1964, 37, Abstr. No. 1478), neither detergents containing a high number of condensed molecules of ethylene oxide (represented by Slovasol O, a condensation product of oleyl and cetyl alcohols with 20 molecules of ethylene oxide) nor those with a low number of molecules of ethylene oxide (represented by Slovasol S, a condensation product of lauryl alcohol with 4 molecules of ethylene oxide) interfered with processes of purification or nitrification in the activated-sludge tank when present in the influent in concentrations of 10 or 20 mg per litre. but concentrations of 20 mg per litre caused foaming. although the foam was coarser, less stable, and less in quantity than that produced by Dubaral. Although Slovasol S is rapidly attacked by bacteria, Slovasol O is not degraded and may cause foaming in streams if the sewage-works effluent is insufficiently diluted. However, some of the Slovasol O is adsorbed on the activated sludge and discharged with the excess sludge into the digestion tanks. Determinations of chemical oxygen demand showed that the 4 hour permanganate test is not suitable for determining pollution by non-ionic detergents, as the values obtained are too low; the dichromate reflux method is more suitable. |
| Is Certified Translation | No |
| Dupe Override | No |
| Comments | Journal:Sb. vys. Sk. chem.-technol. Praze. Technol. Vod. ISSN: |
| Is Public | Yes |