Biological Waste Treatment and Pollution Control

5096579

A N A E R O B I C D I G E S T E R

Jeff P Jordan, James D McElvaney assigned to Unisyn

An anaerobic digester for digesting animal manure and other biologically degradable material contains support media for enhancing the contact between the microbes in the digesting mass and the available nutrients. The digester in- cludes a novel fluid circulation and distribution system. The distribution system prevents build up of heavy material in the bot tom of the digester and prevents agglomeration of light material at the top of the digester. The digesting fluid travels over a floating weir into an intake and impeller assembly. The impeller drives the fluid through a conduit located adjacent the floor of the digester. Nozzles in the conduit project the fluid down- wardly toward the floor thus causing a sweeping action on the floor. Fluid then flows upwardly past the support media. Risers are provided at the ends of the conduit, which terminate in nozz- les at the surface of the digesting liquid. The noz- zles direct the flow of digesting material back toward the fluid inlet and also sweep the corners of the digester to prevent material accumulation.

5096588

M E T H O D A N D S Y S T E M F O R O P T I M I Z I N G T H E O P E R A T I O N

O F A T R I C K L I N G F I L T E R

Orris Albertson

A method and system for optimizing the opera- tion of a trickling filter. Optimization is obtained

by using a pair of controlling devices, a timer and an electric motor in combination. The electric motor rotates the distributor mechanism of the trickling filter in response to signals transmitted thereto by the first and second controller. The timer activates the first controller during opera- tion to provide a SK value of between 25-500 ram/pass. During non-peak hours, the timer ac- tivates the second controller for flushing the bio- mass used in the trickling filter operation. The flushing is accomplished at SK values of between 200-1000 mm/pass. A method is also disclosed incorporating the above system.

5098567

W A S T E W A T E R T R E A T I N G P R O C E S S

Takesh Nishiguchi, Kyoto, Japan assigned to Nishihara Environmental Sanitation Research Corporat ion Limited

A waste water treatment process wherein an iron contactor or iron contactors are immersed in a treatment tank, into which waste water flows. In the treatment tank sulfate reducing bacteria are made to coexist with activated sludge or bio- filters, wherein a velocity of flow of agitating stream on the outer surfaces of said iron con- tactor or contactors is set at 10 to 20 cm/sec, un- der an aerobic treatment. Iron ions are made to elute from said iron contactor or contaetors by utilizing electrochemical iron corrosion through the agency of oxygen concentration cells on the outer surfaces of said iron contactor or con- tactors on conditions that dissolved oxygen con- centration in the treatment tank is 1 to 3.2 mg/l and the oxidation-reduction potential is -200 to - 400 millivolts (mV). Under an anaerobic treat-

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