| 摘要 |
<p>1354585 Biologically treating wastes ALFALAVAL AB 22 Sept 1971 [2 Oct 1970 9 Sept 1971] 44212/71 Heading C1C A biological process comprises contacting an aqueous liquid containing organic material and thermophilic microorganisms and having a BOD 5 of at least 1500 mg O 2 /l., with air, oxygen or oxygen-enriched air, the liquid being maintained by the activity of the microorganisms and without additional heating at a temperature of at least 42‹ C. The liquid may be a diluted whey or manure. The liquid may also contain mesophilic micro-organisms. A layer of foam formed on the liquid during decomposition may be maintained at a constant thickness. Protein may be recovered from the foam. In Fig. 1 liquid which has been mixed in container 1 is pumped into container 7 where it undergoes decomposition and is mixed with air supplied through pipe 9, by propeller 8. Foam layer 14 is broken up by rotary knife 15. Foam and liquid is discharged into reservoir 18 and the liquid is discharged therefrom through container 1 when the latter is empty. In another embodiment (not shown) the foam and liquid are discharged from container (7) through separate outlets, the foam being filtered and the liquid obtained from the foam being recycled to container (7) via container (1).</p> |
