Abstract: An inspection lens, including a lens tube having a central longitudinal axis and a plurality of axially aligned optical elements, including an outermost element. A sheath surrounding the lens tube and defining there between an annular air flow channel. The sheath has a diversion nozzle at a distal end, terminating in a lens tip. The diversion nozzle is configured to divert the air flow in the annular channel inward toward the longitudinal axis and at a slight reverse angle of between 0-18 degrees relative to a plane normal to the axis and back toward the outermost element creating a reverse oblique impinging jet inside said lens tip that minimizes any recirculation zone in front of the outermost element.

Abstract: An imaging system with the ability to produce clear images of deposits inside operating high temperature process equipment such as kraft recovery boilers and power utility boilers uses a terahertz/mm-wave imaging system. This system allows direct inspection capability and the ability to directly measure deposit thickness on tubes and other interior surfaces at all locations within the boiler and precipitator. Terahertz and mm-wave imaging systems employ active imaging in which a beam of terahertz or mm-wave radiation generated within the imaging system is used to illuminate a region of the scene under investigation. The reflected radiation is collected by a lens or mirror system and focused onto a detector that converts the collected radiation into an electrical signal. Both the illuminating beam and the receiving optics are scanned across the scene in a raster fashion to produce a time-varying signal that is converted into an image of the scene.

Abstract: An imaging system with the ability to produce clear images of deposits inside operating high temperature process equipment such as kraft recovery boilers and power utility boilers uses a terahertz/mm-wave imaging system. This system allows direct inspection capability and the ability to directly measure deposit thickness on tubes and other interior surfaces at all locations within the boiler and precipitator. Terahertz and mm-wave imaging systems employ active imaging in which a beam of terahertz or mm-wave radiation generated within the imaging system is used to illuminate a region of the scene under investigation. The reflected radiation is collected by a lens or mirror system and focused onto a detector that converts the collected radiation into an electrical signal. Both the illuminating beam and the receiving optics are scanned across the scene in a raster fashion to produce a time-varying signal that is converted into an image of the scene.

Abstract: A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system for information to enable a distributed control system by which the boilers are operated to operate said boilers more efficiently. The data processing system includes an image pre-processing circuit in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. It also includes an image compensation system for array compensation to correct for pixel variation and dead cells, etc., and for correcting geometric distortion. An image segmentation module receives a cleaned image from the image pre-processing circuit for separating the image of the recovery boiler interior into background, pendant tubes, and deposition.

Abstract: A sensing system simultaneously obtains images and surface temperatures of processing tubes inside process heaters using an imaging sensor operating in the visible or infrared regions of the spectrum and capable of detecting visible or infrared radiation emitted or reflected from surfaces within the process heater, and of providing an image signal to a display or to an image processor. One or more single element infrared detectors viewing specific regions within the aforesaid image accurately measure the intensity of radiation emitted by surfaces within those specific regions so as to allow the temperature of the surfaces within those specific regions to be inferred.

Abstract: A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system for information to enable a distributed control system by which the boilers are operated to operate said boilers more efficiently. The data processing system includes an image pre-processing circuit in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. It also includes an image compensation system for array compensation to correct for pixel variation and dead cells, etc., and for correcting geometric distortion. An image segmentation module receives a cleaned image from the image pre-processing circuit for separating the image of the recovery boiler interior into background, pendant tubes, and deposition.

Abstract: An acoustic pyrometer measures the average gas temperature across a space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time The acoustic signal generator includes an outer tank closed at top and bottom ends by top and bottom end walls and enclosing an outer chamber. A cylinder is supported within the tank and has top and bottom opposed ends. A mid-plate extends across the cylinder and defines the bottom end, and an axial opening in the mid-plate receives a shaft of a piston assembly having an upper piston and a lower piston at ends of the shaft. A throat is attached to the bottom end, and receives the lower piston. The lower piston seals the throat when received in the throat. The upper piston is slidable in the cylinder under influence of air pressure.

Abstract: A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system for information to enable a distributed control system by which the boilers are operated to operate said boilers more efficiently. The data processing system includes an image pre-processing circuit in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. It also includes an image compensation system for array compensation to correct for pixel variation and dead cells, etc., and for correcting geometric distortion. An image segmentation module receives a cleaned image from the image pre-processing circuit for separating the image of the recovery boiler interior into background, pendant tubes, and deposition.

Abstract: A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions and about 4 or 8.7 microns and directly producing images of the interior of the boiler. An image pre-processing circuit (95) in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. An image segmentation module (105) for separating the image of the recovery boiler interior into background, pendant tubes, and deposition. An image-understanding unit (115) matches derived regions to a 3-D model of said boiler. It derives a 3-D structure the deposition on pendant tubes in the boiler and provides the information about deposits to the plant distributed control system (130) for more efficient operation of the plant pendant tube cleaning and operating systems.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions and about 4 or 8.7 microns and directly producing images of the interior of the boiler. An image pre-processing circuit (95) in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. An image segmentation module (105) for separating the image of the recovery boiler interior into background, pendant tubes, and deposition. An image-understanding unit (115) matches derived regions to a 3-D model of said boiler. It derives a 3-D structure the deposition on pendant tubes in the boiler and provides the information about deposits to the plant distributed control system (130) for more efficient operation of the plant pendant tube cleaning and operating systems.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: A system for monitoring, controlling, and optimizing the operation of a kraft chemical recovery furnace which includes a mechanism for determining carryover particle counts, bed profile information, and temperature information of a smelt the bed over a major portion of the bed. The location and temperatures of high and low temperature spots on the bed can be determined. This information may be displayed in a convenient manner, such as on a common screen, for use by the furnace operator in controlling the furnace. Trending and history of bed performance in relationship to these characteristics may be tracked for use in diagnosing furnace operating problems and in adjusting parameters of the furnace to enhance furnace performance.

Abstract: A method and apparatus for profiling the bed of a furnace involves the production of a digital image of the bed and background. The digital image is processed to determine transitions in the image which correspond to transitions between the bed and background and thereby to the boundary of the bed. Bed characteristics, such as the bed profile, the bed height, the slope of the bed and the volume of the bed are determined from the processed image. The image may be displayed for use in controlling the performance of a furnace. In addition, the determined bed characteristics may be compared with reference bed characteristics, with the differences being displayed, used in controlling the operation of the furnace, or in activating an indicator, such as an alarm, in the event the reference and determined bed characteristics differ by a threshold amount.

Abstract: An apparatus for detecting the presence of carryover particles in an upper region of a furnace, such as a smelt bed boiler, includes plural spaced apart detectors. These detectors monitor discrete portions of the interior of the furnace for the purpose of detecting carryover particles in such monitored portions. Signals indicative of the carryover particles are processed to obtain a count of the carryover particles. The carryover particle count may then be displayed. For example, the signals from all of the detectors may be averaged with trends and overall changes in count rates then displayed. In addition, the counts from the individual detectors may also be displayed to assist an operator in locating the source of excessive carryover particles in the furnace. An image sensor, such as a charged coupled device (CCD) detector, may be used to provide a visual display of detected carryover particles.

Abstract: This invention comprises an optical displacement sensor that uses the inverse-square attenuation of light reflected from a diffused surface to calculate the distance from the sensor to the reflecting surface. Light emerging from an optical fiber or the like is directed onto the surface whose distance is to be measured. The intensity I of reflected light is angle dependent, but within a sufficiently small solid angle it falls off as the inverse square of the distance from the surface.At least a pair of optical detectors are mounted to detect the reflected light within the small solid angle, their ends being at different distances R and R+.DELTA.R from the surface.