PATENT ABSTRACTS 387

of surface basin pressure, adequate levels of oxy- gen in the waste are maintained for biodegrada- tion purposes while unwanted gas, such as carbon dioxide and nitrogen, are disengaged. The pressure on the surface of the waste in the basin is controlled so as to ensure that the con- centration of oxygen in the waste is subsaturated and retained while the unwanted gas concentra- tion is super saturated and becomes disengaged.

4402275

P R O C E S S F O R T H E C O N T I N U O U S B L O W I N G O F F I N E - P A R T I C L E D R E D U C I N G

A G E N T S C O N S I S T I N G P R E D O M I N A N T L Y O F M I N E R A L C O A L I N T O A S H A F T F U R N A C E

Antoin Weiner, Fernan Artois, Raymond Lim- path, Luxembourg, Luxembourg assigned to Arbed S A

A mixture of fine-particle mineral coal and a fine-particle solid carrier of carbon is stored in a bulk store from which the mixture is withdrawn and continuously blown into a shaft furnace, e.g. a blast furnace. Sufficient carbon carder is used to loosen the mixture and to prevent it from caking and sticking. A suitable carbon carrier is particulate compost obtained by rotting household refuse or sewage sludge.

4401565

S Y S T E M S F O R T H E T R E A T M E N T O F O R G A N I C M A T E R I A L A N D

P A R T I C U L A R L Y S E W A G E S L U D G E

Keith A Schimei "

Anaerobic digestion of organic material, par- ticularly biological sludge, such as sewage sludge, is carried out in a closed system having a first digestion tank and a second concentration and partial digestion tank. The concentrated and partially digested sludge is fed to the first tank where it is maintained under vacuum such that an active zone of organic material undergoing digestion is detained therein for a long period of time. The digested sludge is withdrawn against the vacuum and has approximately 80 to 90°,/0 of the organic solids therein mineralized; thus sim- plifying dewatering and ultimate disposal of the sludge. Pathogens including viruses are also removed from the digested sludge. Denitr/fica- tion takes place in the vacuum digester tank and gas consisting essentially of nitrogen is removed. Return sludge from the vacuum digester and in- fluent sludge is fed into the second or con- centrator tank to facilitate reseeding with anaerobic organisms. Both tanks are provided with passageways which are coterminous near the upper ends of the tanks and provided with baffles which direct the flow to be in opposite directions in the passageways, thus providing for stripping of the gas and solid-liquid separation. Gas consisting essentially of methane and car- bon dioxide is produced from the second tank. Supernatant from the second tank may be recir- culated to the source of the sludge to facilitate degradation of remaining organic contaminants.

4400470

U S E O F C O : C U L T U R E S IN T H E P R O D U C T I O N O F E T H A N O L BY

T H E F E R M E N T A T I O N O F B I O M A S S

Joseph G Zeikus, Thomas Ng, Arie Ben-Bassat, Raphael J Lamed ~aigned to Wisconsin Alumni Research Foundation

Production of ethanol and enzymes by fermen- tation of biomass with co-cultures of C. thermo- cellum and C. thermohydrosulfuricum.