Abstract: A method of measuring the amount of substance associated with a material in the presence of a contaminant comprises choosing a first band of radiation which lies outside the absorption band of the substance but within the absorption band of the contaminant. The first band is directed at the material; a first detector is positioned to receive the radiation after impinging the material. The first detector converts the radiation received into a first electrical signal. A second band of radiation, which is chosen to lie within the absorption band of the substance, is also within an absorption band of the contaminant. The second band is directed at the material; a second detector is positioned to receive the radiation after impinging the material. The second detector produces a second electrical signal in response to the radiation received. The second electrical signal is subtracted from the first electrical signal.

Abstract: A heating system for dwellings or other enclosures includes a furnace in which a burner is isolated from a hot air or water system, and receives substantially all of its combustion air from outside the enclosure and preheated. A heat exchanger is provided between exhaust gases from the burner of the furnace and the combustion air.

Abstract: An apparatus to measure select properties such as color, brightness or gloss, of a moving sheet, is insensitive to flutter in the sheet. The apparatus comprises a housing to one side of said sheet. A source is located in the housing; the source is capable of emitting a beam of electromagnetic radiation which is aligned to impinge the sheet. The radiation is selected such that it is capable of being absorbed and being reflected by the select properties of the sheet. A collector is also located in the housing; the collector is capable of receiving a portion of the beam reflected from the sheet. A detector capable of measuring the select properties of the sheet based upon the radiation received by the collector is also provided. The housing is held at a constant distance from the sheet by a stream of fluid from the housing directed to impinge the sheet in a direction substantially perpendicular to the sheet. A standardization member is to the other side of the sheet.

Abstract: An improved precipitator voltage control system including an automatic voltage control (AVC) circuit, a firing circuit, an alarm circuit, a power-saving circuit, a remote set-point control circuit and a power supply, all of which are mounted on a single, readily interchangeable circuit board. The automatic voltage control circuit includes a highly responsive spark detection subcircuit which causes the transformer/rectifier voltage to be reduced to zero at the end of the half-cycle in which a spark occurs and then causes the voltage to remain at zero for a short period of time after which voltage is reapplied in a dual ramp manner causing it to rapidly reach a level below the precipitator arcing potential and then increase at a slower rate to the threshold of sparking. The firing circuit drives silicon-controlled rectifiers (SCRs) through optical couplers which provide several thousand volts of circuit isolation.

Abstract: A process and system to dry wet sewage sludge with hot sand and to burn the dried sludge. The sand is heated in a heating device by burning dried sludge, and the hot sand is mixed with wet sludge in a drying device. Thereby moisture is driven from the wet sludge to dry it. The dried sludge and sand are separated, and the sand returned to the heating device while the dried sludge is burned to heat the sand.

Abstract: In a measuring instrument for obtaining information about a medium through which ultrasonic signals can be transmitted or from which ultrasonic signals can be reflected, transducers (21 and 22) are provided for sending and receiving the ultrasonic signals. Electronic amplification means (25) is provided to amplify received ultrasonic signals to a level suitable for processing by a signal processor (23) to provide the desired information. A power supply (20) is provided for activating the sending and receiving transducers (21 and 22) and the amplification means (25). Strobe switching means (26) is provided for activating the power supply (20) during periodic intervals, leaving intervening spans of time when the power supply (20) is inactive. Capacitive means (32) is provided for activating the amplification means (25) when the power supply (20) is inactive,thereby precluding electronic noise generated by the power supply (20) from establishing a gain limit for the amplification means (25).

Abstract: A machine for dispersing gas bubbles in a liquid includes a horizontal series of adjacent flotation cells without baffles or mechanical gas distribution means. In each cell, an ejection device is mounted to expel a two-phase gas-liquid mixture into the cell. Liquid is pumped into the ejection devices so that the density and energy of the mixture at the point of ejection falls within Region I In FIG. 3.

Abstract: A machine which utilizes hydraulic effects to disperse gas bubbles throughout a contained liquid includes a feed duct mounted to introduce raw liquid into the contained liquid. The feed duct comprises a first hollow tubular member into which a stream of processed liquid is pumped. A second hollow tubular member is affixed outside, and concentric with, the first tubular member so that space is formed around the open end of the first tubular member. Raw liquid is introduced into the space between the two members, and the processed liquid aspirates the raw liquid through the feed duct.

Abstract: A system for drying and burning wet waste materials includes a multiple hearth furnace having an upper, drying zone and a lower, burning zone. Wet waste material is introduced into the upper, drying zone and dried with a stream of hot air, and the stream of air is then conveyed to a condenser to remove water. The stream of air from the condenser is then conveyed to the center column of the furnace wherein it is heated, and the hot air is then introduced into the lower, burning zone of the furnace to aid combustion. Hot gaseous products of combustion are conveyed from the burning zone to an afterburner, and the gases leaving the afterburner are transferred to a heat exchanger and then discharged. In the heat exchanger a stream of ambient air is heated, and the heated air is then conveyed to the upper, drying zone.

Abstract: A resin cartridge injection device for use in roof bolting apparatus in the mining industry includes a turret carrying both the hole drilling carriage and the bolt inserting carriage as well as a feed line for introducing the resin cartridge or cartridges into the drilled hole, before bolt insertion, by way of a flexible hose from a remote control station. The cartridges are conveyed from the control station into the hole pneumatically. Indexing of the turret will select either the drilling carriage, the cartridge inserter or the bolt insertion carriage into an operating position, as desired.

Abstract: The disclosure relates to collector electrodes for electrostatic precipitators and particularly to generally annular in cross section hollow cylindrical collector electrodes having a pair of spaced concentric wall structures with a filler means disposed therebetween, the filler means being a lightweight filler means and hermetically sealed in and between said wall structures. The disclosure also relates to fixture means in the lower ends of the hollow cylindrical collector electrodes, the fixture means comprising internally screw threaded openings in blocks secured or fixed to the lower ends of the collector electrode so as to provide for the use of screw threaded bolts for securing the lower ends of the collector electrode structures in juxtaposition. The disclosure also relates to modifications and/or various species of the lightweight filler means between the inner and outer walls of the collector electrode.

Abstract: An apparatus for clarifying liquid waste having a tank with a center column mounted in its center and suction pipes to remove sludge which has settled to the floor of the tank. The center column is provided with an influent trough to introduce liquid waste into the tank, and ports are formed in the upper part of the column to introduce waste into the influent trough. The ports and the influent trough are located at about the level of the liquid in the tank so that the waste leaving the ports creates a radially outward current on the surface of the liquid in the tank to carry scum towards the periphery of the tank for collection.

Abstract: An apparatus for filter backwashing includes a vessel containing a bed of filter media. Laterals with nozzles are disposed below the filter media to convey backwashing air and water into the filter bed. Below the laterals are located a manifold and a distribution plenum to carry air into the laterals. The manifold and the distribution plenum are separated by a common wall having a plurality of ports to provide communication therebetween. Communication between the distribution plenum and the laterals is provided by a plurality of conduits, one conduit extending into each lateral from the distribution plenum.

Abstract: The following disclosure teaches ways and means for incinerating organic materials in a multiple hearth furnace equipped with an afterburner. In the furnace, the wastes are pyrolyzed in an oxygen deficient atmosphere which is regulated to only partially complete the oxidation of the organic substances which are pyrolyzed from the wastes. In the lower part of the furnace fixed carbon is substantially burned. In the afterburner, air is introduced to complete the oxidation of the partially oxidized substances carried by gases and vapors from the furnace. The air supply to the afterburner is controlled so that, at temperatures above a predetermined temperature, the quantity of air introduced is increased with increasing temperatures and is decreased with decreasing temperatures.

Abstract: The following disclosure teaches means for thickening primary and secondary sewage sludge. The disclosed apparatus comprises a tank having upper and lower feedwells disposed therein. Primary sludge is introduced into the lower feedwell and flows into the lower part of the tank to thicken therein. Secondary sludge is aerated and introduced into the upper feedwell so that it flows therefrom and thickens in the upper part of the tank by flotation type thickening.

Abstract: A machine and process for washing paper stock pulp and similar free-filtering materials includes two or more horizontally-disposed wash drums mounted each in a tank. Two endless filter belts are trained to pass under each of said wash drums and through liquid contained in each of the tanks. A mat of pulp is formed between the two endless filter belts and carried under each of the wash drums for washing therein. Wash liquor passes through the pulp mat as it travels under each of the drums thereby washing the pulp mat, and the liquor passes between the drums by gravity flow. After the pulp has been washed it is removed from between the two belts.

Abstract: The present process and system provides a means for controlling denitrification in an orbital system. The process includes measuring the dissolved oxygen concentration at two or more points in the sewage in the orbital system and controlling the rate of aeration of the sewage according to the dissolved oxygen concentration.

Abstract: A process and system to dry wet sewage sludge with hot sand and to burn the dried sludge. The sand is heated in a sand heater by burning dried sludge, and the hot sand is transferred to a sludge dryer. Wet sludge is mixed with the hot sand in the sludge dryer and thereby moisture is driven off. The dried sludge and sand are separated, and the sand returned to a sand heater while the dried sludge is burned to heat the sand.

Abstract: A flotation process wherein hydraulic effects are used to disperse gas bubbles throughout a contained liquid body with a free surface. The process comprises ejecting a two-phase fluid into the liquid body with the density and the kinetic energy of the ejected fluid per unit of the contained volume being such as to define a point within the area encompassed by Regions I and II in the graph of FIG. 2.

Abstract: In an electrostatic precipitator, a downwardly directed corona discharge is produced at the entrance to dust collecting hoppers attached at the bottom of the precipitator chamber, the corona discharge being produced by an array of corona discharge points connected to a high voltage source and a grounded electrode grid positioned below the corona points near the hopper entrance either in the hopper or in the chamber.