Abstract: A system and method for ozone vent gas reuse is provided. The disclosed system and method involve controlling or conditioning the ozone vent gas stream or degassing unit vent gas stream and directing the stream to a mechanically agitating contactor in an aerobic section of the wastewater treatment system. The oxygen content of the vent gas stream is controlled so as to ensure sufficient oxygenation to the aerobic section of the wastewater treatment system. Control may be effected by adjusting the oxygen content of the vent gas stream in response to sensor or measurement inputs characterizing the gas contents of the vent gas stream or the dissolved oxygen levels. The volumetric flow of the vent gas stream to the aerobic section may also be controlled by adjusting the rotational speed of the mechanically agitating contactor in an aerobic section of the wastewater treatment system.

Abstract: Method and system for treating wastewater includes treating sludge with ozone in a plug-flow type reactor to cause lysis of biosolids in the sludge. The ozonated sludge may be provided to an anaerobic or anoxic section of the wastewater treatment system to aid the denitrification processes occurring in the anaerobic or anoxic section of the wastewater treatment system or to other sections of the wastewater treatment system such as a fermenter, an aerobic digester, or an anaerobic digester.

Abstract: An advanced control system for a membrane bioreactor based wastewater treatment plant is disclosed. The disclosed control system comprises a membrane bioreactor (MBR) system and a microprocessor based controller that receives signals corresponding to selected measured MBR parameters and calculates or estimates one or more MBR calculated parameters including Membrane Conductivity (Fxc); and/or Oxygen Uptake Rate (OUR). The microprocessor based controller compares one or more calculated or estimated MBR parameters to prescribed setpoints or desired ranges and governs one or more pumps and valves in the MBR system to adjust the cleaning cycle the MBR system, the MBR flows in the MBR system, or the influent flow to the biological basin in response thereto.

Abstract: A transducer, system and method of constructing the same that utilizes a composite of piezoelectric pillars. In one embodiment, the invention is an apparatus for generating acoustic energy comprising: a plurality of pillars constructed of a piezoelectric material, the pillars arranged in a spaced-apart manner so that spaces exist between adjacent pillars; the pillars having a width and a height extending between a top surface and a bottom surface, wherein the height of the pillars is greater than the width of the pillars; and the spaces filled with a resilient material so as to form a composite assembly.

Abstract: A process/method for cleaning wafers that eliminates and/or reduces pitting caused by standard clean 1 by performing a pre-etch and then passivating the wafer surface prior to the application of the standard clean 1. The process/method may be especially useful for advanced front end of line post-CPM cleaning. In one embodiment, the invention is a method of processing a substrate comprising: a) providing at least one substrate; b) etching a surface of the substrate by applying an etching solution; c) passivating the etched surface of the substrate by applying ozone; and d) cleaning the passivated surface of the substrate by applying an aqueous solution comprising ammonium hydroxide and hydrogen peroxide.

Abstract: A system (FIG. 5) and methods for selectively etching silicon nitride in the presence of silicon oxide that provide high selectivity while stabilizing silicon oxide etch rates. The invention comprises a processing chamber (10), dispense lines (20, 21, 22), feed lines (30, 31, 32), a recirculation line (40), a process controller (200), a concentration sensor (50), a particle counter (55), and a bleed line (90). The invention dynamically controls the concentration ratio of the components of the etchant being used and/or dynamically controls the particle count within the etchant during the processing of the at least one substrate. As a result etchant bath life is increased and etching process parameters are more tightly controlled.

Abstract: An activated sludge wastewater treatment system is provided. The disclosed system includes: an uncovered activated sludge basin; a high purity oxygen aeration system; a secondary clarifier; a return activated sludge line and a waste activated sludge line; wherein the system operates at a solids loading of between about 3000 mg and about 10000 mg of suspended solids per liter of mixed liquor; a dissolved oxygen level in the aeration basin in the range of between about 5 mg to 15 mg; and a solids retention time of between about 7 days and 40 days.

Abstract: An activated sludge wastewater treatment method is provided. The disclosed method includes: receiving a stream of wastewater into a mixed liquor in an uncovered activated sludge basin; introducing high purity oxygen to the mixed liquor in the activated sludge basin to produce euoxic conditions (i.e. a dissolved oxygen level in the range of between about 5 mg to 15 mg) in the activated sludge basin; passing a portion of the mixed liquor in the activated sludge basin through a clarifier to separate activated sludge and produce an effluent stream and an activated sludge stream; and recycling a portion of the activated sludge stream to the activated sludge basin to produce a mixed liquor having a solids loading of between about 3000 mg and about 10000 mg of suspended solids per liter of mixed liquor and a solids retention time of between about 7 days and 40 days.

Abstract: A system and method for the treatment and reduction of sludge via ozonation in a wastewater treatment process is disclosed. The sludge treatment system comprises: a sludge ozonation reactor coupled to an activated sludge treatment basin and adapted to receive a liquid stream of sludge containing biosolids from the activated sludge treatment basin. The sludge treatment system also includes an ozone-enriched gas injection system operatively coupled to the reactor and adapted to inject ozone-enriched gas into the liquid stream at or upstream of the sludge ozonation reactor. The sludge ozonation reactor is configured to allow effective gas-liquid contacting between the ozone-enriched gas and the liquid stream so as to oxidize the biosolids in the liquid stream and initiate bacterial cell lysis thereby reducing the biosolids. Upon reduction of the biosolids, the liquid stream is returned via a return line to the activated sludge basin or other discharge point.

Abstract: A transducer, system and method of constructing the same that utilizes a composite of piezoelectric pillars. In one embodiment, the invention is an apparatus for generating acoustic energy comprising: a plurality of pillars constructed of a piezoelectric material, the pillars arranged in a spaced-apart manner so that spaces exist between adjacent pillars; the pillars having a width and a height extending between a top surface and a bottom surface, wherein the height of the pillars is greater than the width of the pillars; and the spaces filled with a resilient material so as to form a composite assembly.

Abstract: A system and method for the ozone treatment of wastewater is disclosed. The disclosed wastewater treatment system includes a high selectivity reactor coupled to an activated sludge treatment basin. The high selectivity reactor is adapted to receive a stream containing sludge diverted directly or indirectly from the activated sludge treatment basin. The disclosed wastewater treatment system and method is adapted to inject a chemical agent, such as ozone-enriched gas, into the diverted stream for treatment within the high selectivity reactor for purposes of sludge reduction, foam control, or bulking control. The treated stream is then returned to the activated sludge treatment basin.

Abstract: A system and method for mixing high viscous liquids with gas is provided. The disclosed embodiments include a reactor or mixing vessel having a draft tube disposed therein, a gas injection subsystem adapted to inject gas into the reactor or mixing vessel proximate the entrance of the draft tube. The embodiments also include an agitator disposed within the draft tube which makes the draft tube the primary site for the gas-liquid mixing. In particular, the agitator is adapted to create gas bubbles having an average diameter between about 0.3 mm and 3.0 mm which are then ejected into the reactor or mixing vessel. The mass transfer efficiency associated with the present system and method is enhanced from the combined effect of gas dissolution into the high viscous liquid within the draft tube and greater bubble residence time within the high viscous liquid.

Abstract: A system and method for oxygenating an aerobic sludge digester is provided. The disclosed embodiments include an aerobic sludge digester tank or vessel having a mechanically agitated contactor disposed therein, an oxygen injection subsystem adapted to inject oxygen into the digester tank proximate the mechanically agitated contactor. The embodiments of the mechanically agitated contactor include an agitator or impeller disposed within the draft tube which makes the draft tube the primary site for the gas-liquid mixing. In particular, the agitator or impeller is adapted to create gas bubbles having an average diameter between about 0.3 mm and 3.0 mm which are then dispersed into the aerobic digester. The mass transfer efficiency associated with the present system and method is enhanced from the combined effect of oxygen dissolution into the sludge and greater bubble residence time.

Abstract: An activated sludge wastewater treatment system is provided. The disclosed system includes: an uncovered activated sludge basin; a high purity oxygen aeration system; a secondary clarifier; a return activated sludge line and a waste activated sludge line; wherein the system operates at a solids loading of between about 3000 mg and about 10000 mg of suspended solids per liter of mixed liquor; a dissolved oxygen level in the aeration basin in the range of between about 5 mg to 15 mg; and a solids retention time of between about 7 days and 40 days.

Abstract: An activated sludge wastewater treatment method is provided. The disclosed method includes: receiving a stream of wastewater into a mixed liquor in an uncovered activated sludge basin; introducing high purity oxygen to the mixed liquor in the activated sludge basin to produce euoxic conditions (i.e. a dissolved oxygen level in the range of between about 5 mg to 15 mg) in the activated sludge basin; passing a portion of the mixed liquor in the activated sludge basin through a clarifier to separate activated sludge and produce an effluent stream and an activated sludge stream; and recycling a portion of the activated sludge stream to the activated sludge basin to produce a mixed liquor having a solids loading of between about 3000 mg and about 10000 mg of suspended solids per liter of mixed liquor and a solids retention time of between about 7 days and 40 days.

Abstract: A system and method for mixing high viscous liquids with gas is provided. The disclosed embodiments include a reactor or mixing vessel having a draft tube disposed therein, a gas injection subsystem adapted to inject gas into the reactor or mixing vessel proximate the entrance of the draft tube. The embodiments also include an agitator disposed within the draft tube which makes the draft tube the primary site for the gas-liquid mixing. In particular, the agitator is adapted to create gas bubbles having an average diameter between about 0.3 mm and 3.0 mm which are then ejected into the reactor or mixing vessel. The mass transfer efficiency associated with the present system and method is enhanced from the combined effect of gas dissolution into the high viscous liquid within the draft tube and greater bubble residence time within the high viscous liquid.

Abstract: A method of oxygen-free heat treatment of a steel part in an atmospheric pressure furnace is disclosed. The present batch treatment process employs an oxygen-free controlled gas atmosphere including hydrogen gas in concentrations between about 1.0 percent to 10.0 percent, a hydrocarbon gas, such as propylene, in concentrations of between about 0.1 percent and 10.0 percent that varies as a function of time, with the balance of the gas atmosphere being nitrogen. The present continuous furnace treatment process employs a plurality of zones with each zone including an oxygen-free controlled gas atmosphere including hydrogen gas in concentrations between about 1.0 percent to 10.0 percent that varies across the different zones, a hydrocarbon gas, such as propylene, in concentrations of between about 0.1 percent and 10.0 percent that varies across the different zones, with the balance of the gas atmosphere within each zone being nitrogen.

Abstract: A method of controlling an oxygen-free heat treating process in an atmospheric pressure furnace is disclosed. The present method employs an oxygen-free gas atmosphere including hydrogen gas in concentrations between about 1.0 percent to 10.0 percent, a hydrocarbon gas, such as propylene, in concentrations of between about 0.1 percent and 10.0 percent that varies as a function of time, with the balance of the gas atmosphere being nitrogen. The presently disclosed oxygen-free carburization process uses a precisely controlled gas atmosphere to minimize inter-granular oxidation, eliminate the formation of soot and cementite, and avoid hydrogen embrittlement.

Abstract: A method of oxygen-free heat treatment of a steel part in an atmospheric pressure furnace is disclosed. The present method employs an oxygen-free controlled gas atmosphere including hydrogen gas in concentrations between about 1.0 percent to 10.0 percent, a hydrocarbon gas, such as propylene, in concentrations of between about 0.1 percent and 10.0 percent that varies as a function of time, with the balance of the gas atmosphere being nitrogen. The presently disclosed oxygen-free heat treatment process, preferably a carburization process, uses a precisely controlled atmosphere to minimize inter-granular oxidation, eliminate the formation of soot and cementite or other metallic carbides, and avoid hydrogen embrittlement.

Abstract: A system and method for the treatment and reduction of sludge via ozonation in a wastewater treatment process is disclosed. The sludge treatment system comprises: a sludge ozonation reactor coupled to an activated sludge treatment basin and adapted to receive a liquid stream of sludge containing biosolids from the activated sludge treatment basin. The sludge treatment system also includes an ozone-enriched gas injection system operatively coupled to the reactor and adapted to inject ozone-enriched gas into the liquid stream at or upstream of the sludge ozonation reactor. The sludge ozonation reactor is configured to allow effective gas-liquid contacting between the ozone-enriched gas and the liquid stream so as to oxidize the biosolids in the liquid stream and initiate bacterial cell lysis thereby reducing the biosolids. Upon reduction of the biosolids, the liquid stream is returned via a return line to the activated sludge basin or other discharge point.