PATENT ABSTRACTS 4a9

concentrations greater than 5,000 ppm and em- lower end of the bubble plate-type column (2). It ulsifier concentrations greater than 2,000 ppm. then flows through the plates (3) and issues again Rates of solvent biodegradation range from as purified gas at the top of the plate column (2). 0.095 mg/L.min to about 7.0 mg/Lmin. When the plate column is used for purifying

waste water, the waste water to be purified is conveyed from top to bottom through the plate

4867883 column (2) and is traversed by air, oxygen or oxygen-containing gas. At the same time, a pro-

H I G H - R A T E B I O L O G I C A L W A S T E portion of the biomass is separated from the W A T E R T R E A T M E N T P R O C E S S purified waste water and re-circulated into the

U S I N G A C T I V A T E D S L U D G E entering waste water or into the column. The R E C Y C L E waste water to be purified flows successively over

the plates (3) to the liquid outlet (l 1). From here, the clarified waste water flows out through the

Glen Daigger, James R Borberg, Liliana M overflow (13). This process is suitable, in par- Morales assigned to Hampton Roads Sanitation titular, for highly charged waste water, par- District of the Commonwealth of Virginia ticularly ifa compact structure is required during

construction of the apparatus. A high-rate biological waste water treatment process for removing organic matter, phosphorus and nitrogen nutrients from 4880473 municipal waste water comprising the steps of mixing the influent waste water in an initial P R O C E S S F O R T H E anaerobic reactor zone to maintain the bio- logical solvents in suspension with a denitrified P R O D U C T I O N O F mixed liquor from a downstream anoxic reactor F E R M E N T A B L E S U G A R S F R O M zone, typically at a flow rate of 0.5 to two times B I O M A S S the waste water flow rate. The reactor zone ser- ves to select microorganisms capable of ac- Donald S Scott, Ja Piskorz, Waterloo, Canada cumulating quantities of phosphorus in excess of assigned to Canadian Patents & Development that required for simple cell growth and Ltd reproduction. The phosphorus removal occurs due to the removal of excess sludge (waste ac- A process for the production of fermentable sug- tivated sludge) produced in the process wherein ars from wood or other cellulose-containing bio- such sludge can be removed from the clarifier masses, comprises the steps of (a) hydrolysing undertow or as a mixed liquor directly from the the biomass with a dilute sulfuric acid to dissolve biological reactor, hemicellulose while leaving most of cellulose in a

solid phase, (b) separating the c¢llulose~ containing solid phase, (c) subjecting the solid

4869824 phase to rapid pyrolysis at a temperature of 400 degrees-600 degrees C. at atmospheric pressure,

B U B B L E P L A T E S Y S T E M F O R preferably in a fluidized bed reactor with a short B I O L O G I C A L P U R I F I C A T I O N O F vapor residence time, to obtain a crude pyrolysis

A I R A N D W A S T E W A T E R product by condensing the pyrolytic vapors, (d) adjusting the water content of the crude product

Thomas Melin, Hubert Stracke, Otto Barth, to form an aqueous phase with high carbohy- Cologne, Federal Republic Of Germany as- drate content and a water-insoluble phase con- signed to Bayer Aktiengesellschaft taining lignin-derived material, and (e)

separating the aqueous phase. Optionally, the The outgoing gas or waste water is conveyed aqueous phase may be purified, e.g. by absorp- through a gas-liquid contact apparatus in which tion. biological purification takes place. A bubble plate-type column (2) is used as gas-liquid con- 4880542 tact apparatus. The biomass is distributed over the plates (3) in the form of an aqueous suspen- B I O F I L T E R F O R T H E sion with a layer height corresponding to a liquid content per plate greater than 0.07 m3/m2, pre- T R E A T M E N T O F S O U R W A T E R ferably greater than 0.15 m3/m2 of column cross-sectiOn. During the biological purification Kerry L Sublette assigned to Combustion of gas, the gas to be purified is supplied at the Engineering Inc

490 PATENT ABSTRACTS

A process for oxidizing the sulfide (H2S, HS-, S- gas from each gas well is measured, thereby pro- 2) in sour water to convert the sulfide to sulfate riding information for controlling the flow of by producing a sulfide tolerant strain of gas from the corresponding wells. The apparatus Thiobacillus denitrificans and then co- disclosed by the invention comprises a control immobilizing the T. denitrificans and CaCO3 on chamber connected to one or more gas wells on or within a carrier to form the biofilter. The sour the one hand and to a gas furnace over a gas fan water is contacted with the biofilter in a con- on the other hand. A temperature meter located tinuous process, in the gas flow is connected to a microprocessor

which is connected to an adjustment valve located in the control chamber.

4885094

A N A E R O B I C D I G E S T I O N 4891459 P R O C E S S , A N D F O R C E D F E D

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

Vadake Srinivasan, Wilbur Monceaux assigned B I O M A S S A N D P R O C E S S I N G O F to Micro Pure Systems Inc O I L A N D C H A R

An anaerobic process for the digestion of or- James A Knight, Charles Gorton assigned to ganic wastes, and novel anaerobic digester. In Georgia Tech Research Corporation digestion of the organic wastes in the presence of anaerobic microorganisms, at anaerobic condi- Entrained pyrolysis of lignocellulosic material tions, the carbon:nitrogen and proceeds from a controlled pyrolysis-initiating nitrogen:phosphorus ratios of the digestion are temperature to completion of an oxygen free en- adjusted to optimize the rate of anaerobic diges- vironment at atmospheric pressure and con- tion, generally only about 12 to 72 hours, or less, trolled residence time to provide a high yield being required to produce a stabilized low solids recovery of pyrolysis oil together with char and sludge and clean liquid effluent. The anaerobic non-condensable, combustible gases. The resi- digester is designed to facilitate this process, and dence time is a function of gas flow rate and the is transportable from site to site. initiating temperature is likewise a function of

the gas flow rate, varying therewith. A controlled initiating temperature range of about 400

4890672 degrees C. to 550 degrees C. with corresponding gas flow rates to maximize oil yield is disclosed.

M E T H O D O F C O N T R O L L I N G T H E F L O W O F L A N D F I L L G A S F R O M S A N I T A R Y L A N D F I L L S 4894162

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

O R G A N I C S U B S T A N C E S A T Lars Hall, Liding Sweded assigned to RAGN- W A S T E W A T E R T R E A T M E N T SELLSFORETAGEN AB P L A N T S

A method of controlling the recovery of landfill Richard Cournoyer, Thomas Jakopp, G E gas from a sanitary landfill and apparatus for Friberg assigned to Ciba-Geigy Corporation performing the method. Landfill gas, which mainly consists of methane and carbon dioxide, A method and apparatus for purifying industrial is formed by anaerobic decomposition of the or- waste fluids by an aerobic biological treatment is ganic content of the refuse. This process provided herein, which is capable of con- develops a very small amount of heat. If more currently purifying waste gases emanating from gas is drawn frgm the sanitary landfill than is such waste liquids. The improvement relates to formed by the anaerobic decomposition, air is the elimination or reduction of odors and drawn into the landfill. The decomposition volatile organic substances by enclosing all tanks thereby becomes aerobic, developing large quan- and basins from the influent of the waste water tities of heat and increasing the content of car- treatment plant up to the aeration treatment bon dioxide and nitrogen in the gas. According zone for the liquid waste water and venting these to the disclosed method, the temperature of the gases to an aerobic digester and/or an aeration