Abstract: Characteristics of a flame within a turbine or burner are determined based upon ultraviolet, visible, and infrared measurements of the flame. The measurements include the amplitude of frequency bands that are indicative of an efficient combustion process, such as those that increase when the flame temperature increases. The measurements also include the amplitude of frequency bands that are indicative of an inefficient combustion process, such as those that do not vary, increase a relatively small amount, or decrease when the flame temperature increases. The temperature of the flame may therefore be determined accurately, to facilitate efficient operation of the turbine or burner, while minimizing polluting emissions.

Abstract: An automatic safety system for a fluid fuel air heating furnace. The safety system utilizes a double-sided carbon monoxide sensor for detecting unsafe levels of carbon monoxide interiorly and exteriorly of the furnace's heated air duct and a single-sided carbon monoxide sensor for detecting unsafe levels of carbon monoxide interiorly of the furnace's flue pipe. The sensors employ carbon monoxide detector chips which are electrically conductive in normal conditions, but become non-conductive when exposed to levels of carbon monoxide that are deemed unsafe for humans. The sensors are incorporated in an electrical circuit for energizing a solenoid valve which valve, when energized, opens to permit fuel flow to the furnace. Detection of unsafe levels of carbon monoxide will result in the sensors becoming non-conductive, thereby causing the solenoid valve to become de-energized and to close thereby preventing fuel flow to the furnace.

Abstract: A boiler having a combustor for combusting an air/gas fuel mixture, the combustor including a heat exchanger which conducts coolant therethrough surrounding the combustion chamber and a fan coupled to an air line provides a flow rate of air in the air line. A gas line is coupled at one end to a source of gas and at another end to the air line so as to produce a mixture of gas and air. Means for measuring a property of the air/gas fuel mixture characteristic of its combustibility are utilized. A valve coupled to said gas line is operative to control a flow rate of gas in response to a control signal from the means for measuring. A temperature sensor takes a temperature measurement of the coolant after passing through the heat exchanger and transmits the temperature measurement to the speed control unit. The speed control unit slows down the speed of the fan when the coolant temperature approaches a preset limit.

Abstract: An intelligent burner control apparatus is provided for controlling the rate of air and fuel flow in a burner system from air and fuel supplies to a burner. The apparatus includes a peer-to-peer communication network including a plurality of network control modules that communicate with each other over the communication network. The apparatus further includes a brain module including one of said network control modules coupled to the communication network, air and fuel flow controllers including one of said network control modules coupled to the communication network, and air and fuel flow regulators including one of said network control modules coupled to the communication network. The brain module is configured to send air and fuel setpoint signals over the communication network to the air and fuel flow controllers.

Abstract: A hot fluid generating apparatus includes a combustion chamber, a regenerative combustion burner, a fluid passage formed along a wall structure of the combustion chamber, and a device for causing fluid to flow in the fluid passage. The combustion chamber has a flame radiation heat transfer only as a heat transfer portion. A portion of the wall structure opposite to the burner is utilized as a radiation heat transfer portion. A portion of exhaust gas from the burner is recirculated to the supply air to suppress generation of NOx. A portion of the wall structure close to the burner is formed to be a cone.

Abstract: Apparatus provides an air/fuel mixture to a fully premixed burner and comprises means for providing fuel at a variable flow rate to the burner, means for supplying air at a variable flow rate to the fuel to form the mixture, means for sensing aeration of the fuel combustion products and control means for controlling the fuel flow rate in dependence upon a heat output demand and the air flow rate in dependence upon both the fuel flow rate and the sensed aeration in such a way that the air flow rate is sufficient to maintain the aeration at a predetermined value, the controller, in use, maintaining the fuel flow rate at one of a number of predetermined values and the air flow rate at a corresponding one of a number of differing predetermined values, each set of predetermined values being characterized by a constant value of the ratio between successive values.

Abstract: Systems and methods are disclosed that optimize the combustion process in various reactors, furnaces, and internal combustion engines. Video cameras are used to evaluate the combustion flame grade. Depending on the desired form, standard or special video devices, or beam scanning devices, are used to image the combustion flame and by-products. The video device generates and outputs image signals during various phases of, and at various locations in, the combustion process. Other forms of sensors monitor and generate data signals defining selected parameters of the combustion process, such as air flow, fuel flow, turbulence, exhaust and inlet valve openings, etc. In a preferred form, a neural networks initially processes the image data and characterizes the combustion flame. A fuzzy logic controller and associated fuzzy logic rule base analyzes the image data from the neural network, along with other sensor information.

Abstract: An unburned carbon and other combustibles monitoring and control system for a fly ash producing fossil-fueled boiler, such as a pulverized coal fired boiler. An infrared imaging camera counts the moving hot particles entrained in the hot gases downstream of the furnace region of the boiler and provides a first signal representative of the number of hot particles in the hot gases over a predetermined period of time. A signal processor is connected to the infrared imaging camera for counting the hot particles for receiving the signal representative of the number of particles in the hot gases and providing a second signal representative of the mass flow of unburned carbon and other combustibles content of the fly ash produced by the boiler, the second signal being a function of the first signal.

Abstract: Apparatus provides an air/fuel mixture to a fully premixed burner (4) and comprises a fuel line for providing fuel to the burner (4) a fan for supplying air at a variable flow rate to the fuel to form the mixture, a sensor (30) for sensing aeration of the fuel combustion products and a controller (26) for controlling the air flow rate in dependence upon the aeration sensed in such a way that the air flow rate is sufficient to maintain the aeration at or close to a predetermined value, the controller, in use, maintaining the air flow rate at one of a number of differing predetermined values which are in the form of a geometric series characterized by a constant value of the ratio between successive values.

Abstract: A gas heater is provided with a combustion status sensor that provides heater performance data to a controller that controls the heater according to the sensor data and stored calibration parameters optimized for the particular heater.

Abstract: Systems and methods are disclosed that optimize the combustion process in various reactors, furnaces, and internal combustion engines. Video cameras are used to evaluate the combustion flame grade. Depending on the desired form, standard or special video devices, or beam scanning devices, are used to image the combustion flame and by-products. The video device generates and outputs image signals during various phases of, and at various locations in, the combustion process. Other forms of sensors monitor and generate data signals defining selected parameters of the combustion process, such as air flow, fuel flow, turbulence, exhaust and inlet valve openings, etc. In a preferred form, a neural networks initially processes the image data and characterizes the combustion flame. A fuzzy logic controller and associated fuzzy logic rule base analyzes the image data from the neural network, along with other sensor information.

Abstract: A pair of reference electrodes and a flame rod are placed in contact with charged particles in a flame produced by a burner. When a voltage is applied between the flame rod and the burner by a power source, a current (I.sub.fr) flows between them due to the flame conductivity. A potential difference (V.sub.12) between the pair of reference electrodes is detected by a potential difference detector. The dynamic flame impedance between the pair of reference electrodes is defined as the slope of the I.sub.fr -V.sub.12 relationship and is independent of I.sub.fr.

Abstract: A combustion control method includes the steps of providing an oxygen sensor within a furnace or at a flue of the furnace, detecting an oxygen concentration of exhaust gas, and controlling an air ratio. A regenerative combustion apparatus includes a regenerative combustion burner, an oxygen sensor disposed in an air supply and gas exhaust passage of the burner. A combustion control method and apparatus includes the steps of switching an electrical voltage imposed on an oxygen sensor between a first electrical voltage and a second electrical voltage near 0 V, conducting an air ratio control when the imposed voltage is at the first voltage and monitoring unburnt components included in exhaust gas when the imposed voltage is at the second voltage.

Abstract: In a cross flow type burner apparatus, a burner is provided to which a gaseous fuel and air are supplied by a blower. An air reduction member is provided to reduce an amount of air supplied to specified flame holes of the burner wherein the reduced amount of air is less than the amount of air supplied to the other flame holes. A temperature sensor is provided to detect the burning condition of flames built up on the specified flame holes. A safety member is activated depending on an output generated from the temperature sensor.

Abstract: The method of invention involves the steps of placing a small hole in the flue of a furnace or the like; inserting the elongated probe of a CO tester in the hole; visually ascertain from the tester the CO content of the gas in the flue, comparing the measured CO content of the gas in the flue against a predetermined perimeter range of CO content between 0-45 ppm for furnaces, and 0-85 ppm for hot water boilers to determine the cleanliness of the combustible materials in the gas being combusted, and resealing the hole in the flue.

Abstract: A system for automatically admitting and regulating the flow-rate of an alkaline substance admitted to the combustion chamber (10) of a refuse incineration plant for the hot destruction of the acids contained in the combustion fumes, comprising sensors (22, 23, 24, 25, 51, 124, 140) for detecting the concentration of the acids in the fumes in the combustion chamber (10) and working conditions of the plant such as temperature, flow-rate and humidity of the fumes, and processing means (26, 27) connected to the sensors for identifying, in dependence on the concentration of acids and of the working conditions, a flow-rate of an alkaline substance to be admitted to the combustion chamber in order to achieve a destruction yield which reduces the concentration of acids in the fumes discharged from the plant to a predetermined value, and for operating flow-rate regulation members (40) for admitting to the combustion chamber the flow-rate of an alkaline substance thus identified.

Abstract: A catalytic differential gas combustible microcalorimeter sensor for monitoring the exhaust gas conversion for monitoring the exhaust gas conversion efficiency of a catalytic converter. The catalytic calorimetric sensor disclosed includes a sol-gel processed washcoat and sol-processed catalytically active metal particles. Sol-gel processing creates a washcoat with high surface area and controlled porosity which increases the sensitivity, durability, and reproducibility of the resultant sensor.

Abstract: A heater including a housing, a heating assembly having a burner, and at least one of an oxygen level detection assembly adapted to distinguish between a relatively normal oxygen level, a relatively low oxygen level and relatively unsafe oxygen, a carbon monoxide sensor and a combustible gas sensor. The heater may also include an indicator adapted to produce at least one of an audible indication and a visible indication in response to a detection of a relatively low oxygen level, a detection of a predetermined level of carbon monoxide, or a detection of combustible gas.

Abstract: A gas flow rate controller arranged between a gas burner and a flammable gas source and a combustion-assisting gas source includes a gas flow rate setting means for producing a flow rate setting signal corresponding to a preset flow rate of gas flowing toward the gas burner. A ratio setting means produces a flammable gas setting reference signal and a combustion-assisting gas flow rate setting signal at a predetermined ratio, based on the flow rate setting signal produced by the gas flow rate setting means. The flow rate of the flammable gas detected is compared with the flammable gas setting reference signal produced and the flow rate of the combustion-assisting gas detected is compared with the combustion-assisting gas flow rate setting reference signal produced. Control valves are feedback controlled so that any differences therebetween will become zero. Thus the mixing ratio between the gases is kept constant even if the gas pressures change.

Abstract: A carbon monoxide detection and automatic deactivation system including a fuel burner having a fuel supply conduit coupled thereto. A pilot igniter is situated adjacent to a pilot supply conduit and is adapted to provide a flame in an interior space of the burner upon the actuation thereof. A thermocouple is positioned adjacent to the pilot igniter for producing an electric current upon the detection of heat. Also included is an electromechanical fuel valve comprising a solenoid adapted to allow the supply of fuel to the burner upon the receipt of current via the thermocouple and further preclude said supply upon the lack thereof. Finally, a switch mechanism is electrically coupled between the thermocouple and the solenoid. The switch mechanism has a first orientation for allowing current to pass therebetween with the absence of carbon monoxide and a second orientation for precluding current to pass therebetween with the presence of carbon monoxide.

Abstract: A system including a resonant cavity for measuring in-situ and in real time the Carbon content of the fly ash produced from the combustion process occurring within a pulverized coal-fired steam generator. The resonant cavity basically includes an intelligence section, a transmitting section, a cavity section and a receiving section. When the system including the resonant cavity is so employed the measurements gained therefrom may be utilized either by an operator or as input to a boiler control system or both in order that corrective action may be implemented when such is required.

Abstract: Disclosed is a method to make and an apparatus for monitoring the exhaust gas conversion efficiency of a catalytic converter. The catalytic calorimetric sensor disclosed includes a sol-gel processed washcoat and sol-processed catalytically active metal particles. Sol-gel processing creates a washcoat with high surface area and controlled porosity which increases the sensitivity, durability, and reproducibility of the resultant sensor.

Abstract: A method and apparatus is disclosed for controlling staged combustion systems of the type used for combusting two reactants wherein at least one reactant is supplied as two flows, the first of which is combusted with the flow of the other reactant in a primary stage and the other of which is combusted with the exhaust of the primary stage in a secondary stage. In the present invention, the respective flows are monitored and controlled to provide a desired equivalence ratio for both the first stage and for the burner overall which is adaptable in response to variable input conditions. By controlling the flows in this way, a calculated energy output or adiabatic flame temperature can be produced. The present invention can also control the reactant flows to each stage in response to measured parameters such as flame temperature or emission levels. In this way, the flows can be varied in order to drive the measured parameters to a desired level.

Abstract: A method and system of regulating the air to fuel ratio supplied to a burner to maximize the combustion efficiency. Optical means are provided in close proximity to the burner for directing a beam of radiation from hot gases produced by the burner to a plurality of detectors. Detectors are provided for sensing the concentration of, inter alia, CO, CO.sub.2, and H.sub.2 O. The differences between the ratios of CO to CO.sub.2 and H.sub.2 O to CO are compared with a known control curve based on those ratios for air to fuel ratios ranging from 0.85 to 1.30. The fuel flow is adjusted until the difference between the ratios of CO to CO.sub.2 and H.sub.2 O to CO fall on a desired set point on the control curve.

Abstract: An apparatus is provided for controlling the flow of gas for artificial logs. The apparatus includes a main gas burner and a pilot as well as a gas valve which controls the flow of gas to the main burner and to the pilot. The pilot includes a oxygen depletion sensor. A thermal responsive electrical generator is adjacent to the pilot and is connected to the valve. The output voltage of the generator, while under load, is at least 140 millivolts so as to operate the gas valve, which is capable of full automatic operation without the use of an additional electrical source. In addition, the thermal responsive electrical generator is positioned with respect to the pilot so that gas from the pilot will not continue to burn about the generator when the oxygen depletion sensor senses a predetermined low level of oxygen.

Abstract: Apparatus is provided for detecting faults in a sensor providing an output voltage representative of aeration of a combustible mixture. The apparatus comprises a control box which checks whether the value of a reference voltage with which the output voltage is compared to control the aeration is suitable for causing an intended value of the aeration to be maintained.

Abstract: Method and apparatus for reducing the NOX levels in stack emissions of compact boilers and fluid heaters through selective injection of exhaust flue gases into the combustion process. Flue gas injection into the primary and secondary air of the burner along with flue gas injection directly into the combustion process is utilized. Injection of generated steam obtained from various components of a compact boiler, selectively injected into the combustion process is also provided.

Abstract: A gas vent and burner monitoring system for monitoring a gas burner vent appliance. The system includes an alarm, a first sensor proximate the burner and a second sensor proximate the draft hood. Each sensor detects the occurrence of an event and the respective sensor activates the alarm when the event occurs.

Abstract: Method and apparatus for reducing the NOX levels in stack emissions of compact boilers and fluid heaters through selective injection of exhaust flue gases into the combustion process. Flue gas injection into the primary and secondary air of the burner along with flue gas injection directly into the combustion process is utilized. Injection of generated steam from a compact boiler, selectively injected into the combustion process is also provided.

Abstract: A gas sensor for measuring gas constituents, particularly exhaust gas constituents for an internal combustion engine, comprising a pair of polysilicon plates, each plate supporting a pair of resistors, one serving as a heater and the other as a thermometer, one plate being coated with a catalyst to promote combustion of unburned combustible gas constituents, wherein provision is made for reducing temperature gradients across the plates and for effecting temperature uniformity of the catalyst while maintaining a high degree of structural integrity.

Abstract: A method and apparatus for low NOX combustion of natural gas in a compact steam boiler having output steam delivery controlled by predetermined outlet steam pressure. The compact boiler employs a small high heat release combustor discharging into a forced draft convective heat exchange section. In operation, the compact boiler is completely and automatically self-operating, employing flue gas recirculation (FGR) wherein the FGR is admitted into the burner combustion air through a valve controlled by boiler flue gas NOX content. A novel bell mouthed flue gas scoop is utilized in the boiler stack upstream of the NOX sensor. In an alternate combustion chamber design, a cylindrical water wall coil surrounds the combustion process, increasing boiler efficiency through the inherent large temperature difference between the coil and the combustion in process, along with reducing the combustion temperature and further reducing the NOX content of combustion products.

Abstract: An apparatus is provided for controlling the flow of gas for artificial logs. The apparatus includes a main gas burner and a pilot as well as a gas valve which controls the flow of gas to the main burner and to the pilot. The pilot includes a oxygen depletion sensor. A thermal responsive electrical generator is adjacent to the pilot and is connected to the valve. The output voltage of the generator is at least 250 millivolts so as to operate the gas valve, which is capable of full automatic operation without the use of an additional electrical source. In addition, the thermal responsive electrical generator is positioned with respect to the pilot so that gas from the pilot will not continue to burn about the generator when the oxygen depletion sensor senses a predetermined low level of oxygen.

Abstract: The invention relates to a gas burner system with at least one gas burner comprising: i) a mixing chamber (2) for supplying fuel gas and air; ii) a closed combustion chamber (3) located under the mixing chamber (2) and separated therefrom by a ceramic burner plate (16); iii) a jacket (30, 31) surrounding the combustion chamber (3) and heatable by radiation with an inlet (43) and an outlet (44) for liquid for heating, which jacket (30, 31) is provided with standing fire tubes (35) connecting onto the combustion chamber (3); iv) an outlet (46) for combustion gases; and v) combustion control means (17) situated in the combustion chamber (3) in the vicinity of the burner plate (16) which are connected to a control system.

Abstract: A device to control a gas-fired appliance as a function of the composition of a gaseous fuel. The device includes a thermal conductivity sensor emitting a measurement signal dependent upon the thermal conductivity of the gaseous fuel. An analyzing unit receives the measurement signal and uses it to develop a control signal dependent upon the composition of the gaseous fuel. A control unit receives the control signal and uses it to control the operating parameters of the gas-fired appliance, in the case of a gas engine particularly the parameters of air/fuel ratio, output and angle of advance. The analyzing unit may include an input interface into which data on the type of gaseous fuel components may be entered, which are used for the generation of the control signal. Preferably the control signal is proportional to the available methane number of the gaseous fuel, whereby the operating parameters of the gas engine are controlled so that the methane number required is adjusted to the methane number available.

Abstract: A method and apparatus for applying exhaust gas analysis to simple combustion control systems wherein the fuel flow and air flow control devices are interconnected with fixed mechanical linkage, or interconnected by a single specific signal, between the fuel flow and air flow control devices. An apparatus and method are disclosed to automatically compensate the air-to-fuel ratio, pre-calibrated on a volume basis, for uncontrolled variations of air or fuel quality such as density, BTU content and the like so that the calibration of the rate of combustion air flow relative to the rate of fuel flow will always be substantially correct even while these flow rates are changing.

Abstract: A method and system for controlling and providing guidance in reducing the level of NO.sub.x emissions based on controllable combustion parameters and model calculations while maintaining satisfactory plant performance and not causing other harmful consequences to the furnace. To implement such a system, boiler control values of flow, pressure, temperature, valve and damper positions in addition to emission sensors for data associated with the production of NO.sub.x, O.sub.2, CO, unburned carbon and fuel. This information is received from standard sensors located throughout a boiler which are connected either to a distributed control system (DCS), or another data acquisition system which is time coordinated with the DCS. The DCS passes this information to a computing device which then processes the information by model based optimization simulation programs, also referred to as the NO.sub.x Emissions Advisor.

Abstract: Disclosed is a system for regulating the efficiency of a combustion process by detecting radiant energy emitted from ash particles entrained in the gas stream exiting the combustion chamber of a boiler or incinerator. The intensity of selected wavelengths of light emitted from the particles is indicative of the temperature of the particles. The change in the intensities of the selected wavelengths of light, and thus of the temperature of the gas stream at the furnace exit, is monitored, and a feedback control mechanism is used to regulate one or more combustion, pollution control, or heat transfer parameters thereby maximizing the thermal efficiency of the combustion process in the boiler or incinerator.

Abstract: A combustion control system for a burner having an analog circuit unit which includes a photosensor for detecting combustion flame of the burner, an amplifier for amplifying a detection output from the photosensor, a rectifier for rectifying the amplified signal to a DC component, and an integrator for smoothing the rectified signal to obtain an oscillating power signal.

Abstract: An optical method for monitoring the products of combustion, particularly for the detection of upset conditions in the incineration of hazardous waste, is disclosed. On-line detection of upsets is extremely important to avoid sending untreated waste out the stack plume and to avoid the formation of hazardous products of incomplete combustion, such as dioxins. Small hydrocarbons are the strongest candidates for in situ monitoring of combustion efficiency. The combustion is monitored via infrared absorption using tunable diode lasers (TDLs).

Abstract: Disclosed is an integrated imaging sensor/neural network controller for combustion control systems. The controller uses electronic imaging sensing of chemiluminescence from a combustion system, combined with neural network image processing, to sensitively identify and control a complex combustion system. The imaging system used is not adversely affected by the normal emissions variations caused by changes in burner load and flame position. By incorporating neural networks to learn emission patterns associated with combustor performance, control using image technology is fast enough to be used in a real time, closed loop control system. This advance in sensing and control strategy allows use of the spatial distribution of important parameters in the combustion system in identifying the overall operation condition of a given combustor and in formulating a control response accorded to a pre-determined control model.

Abstract: A fuel/air control system for use in controlling the operation of a surface combustion burner includes a photodetector that provides electrical signal equivalents of burner flame emission to a controller. The controller simultaneously receives signals indicative of the fuel/air mixture. The controller fits the emission and fuel air mixture data to a fourth order polynomial. Thereafter, the mathematical inflection point is computed and the corresponding fuel/air mixture is determined. The controller then generates command signals to adjust and maintain the burner at the inflection point fuel/air mixture. Multiple burner control can also be achieved with the present fuel/air control system without the need to sample exhaust gas.

Abstract: Detecting the presence of PAC's in the effluent of a combustions system by detecting the presence of a high molecular weight PAC's having five or more rings. A position along the effluent stream is selected at which high molecular weight PAC's may be present. The effluent is illuminated with radiation having a wavelength absorbed by the high molecular weight PAC's in the gas phase. The fluorescence from the illuminated effluent is detected, and analyzed by comparison to the known fluorescence of high molecular weight PAC's in the gas phase to determine the presence of the PAC's in the effluent. The effluent composition may be controlled in response to the detection.

Abstract: A control system for a burner is disclosed which detects oxygen concentration in a room using an oxygen sensor, to thereby supply an abnormality detecting signal to at least one of an alarm and a combustion reducing device to actuate it when oxygen concentration is lowered below a predetermined set value. A first comparing device and a reference value storing device are used to cause maximum oxygen concentration detected to be stored as an oxygen concentration reference value in the storing device. A second comparing device compares the deviation between the oxygen concentration reference value and a detected oxygen concentration value with an abnormality judging reference value, to thereby generate the abnormality detecting signal when the deviation is larger than the reference value. The control system is capable of effectively detecting a low oxygen concentration condition without being affected by an ambient temperature.

Abstract: Carbon particulate concentration of diesel exhaust or other sampled gas is measured by collecting the particulate on a high efficiency filter while measuring the amount of sampled gas passing through the filter. The filtered particulate is then heated in an oxygen rich environment to oxidize carbon within the particulate to carbon dioxide. The amount of resulting carbon dioxide is measured with a closed measurement loop to derive a corresponding measurement of the amount of filtered particulate. Particulate concentration is calculated by comparing the amount of carbon particulate with the measured amount of sampled gas passed through the filter. Filtered particulate can be heated incrementally to obtain a measurement of volatile carbon components within the particulate prior to the oxidation of the non-volatile carbon component.

Abstract: An apparatus and method for adjusting the air-fuel ratio of a burner in order to minimize the presence of undesirable emissions in exhaust gases of the burner combustion. A burner calibration is performed by selecting a number of calibration points corresponding to burner fuel positions. Air flow is varied for each calibration point as an exhaust gas analyzer determines the content of exhaust gases of the burner combustion. Air settings for optimal combustion are determined for each calibration point and are stored in a programmable logic controller and software. During plant operation, the programmable logic controller and software adjust the air supplied to the combustion of the burner according to the calibration data and the fuel position of the burner.

Abstract: A process and apparatus for monitoring and ensuring safe operation of unvented kerosene heaters in indoor spaces detects the hazard of incomplete combustion and the concomitant reduced O.sub.2 and increased CO.sub.2 levels in the indoor air. CO.sub.2 level in the indoor air is monitored quickly and accurately, - regardless of the burner's flame height. This is achieved by sensing O.sub.2 level in the burner exhaust which is used as a measure for monitoring the CO.sub.2 level in the indoor air and as a control signal. During burner operation outside a predetermined flame height range, the O.sub.2 detection is used both for restoring a normal heating condition and for monitoring operation at minimum flame height and to generate a warning signal and a delayed automatic shut-down of the burner.

Abstract: A draft control for material processing apparatus, such as asphalt plants, having a chamber through which material to be processed is passed for contact with combustion gases and heat originating in a fuel supplied burner which may require a draft to draw air into the chamber for complete combustion of burner supplied fuel and to exhaust the products of combustion and other gaseous materials from the chamber. The air pollutants and the percent oxygen in the exhausted gases are monitored, and the draft is adjusted between minimum and maximum values for a given burner set point when the air pollutant content of the stack gases exceeds a predetermined maximum limit. The direction of draft adjustment is determined by the percent oxygen in the exhaust gases.

Abstract: An acoustically operated burner control system for optimally controlling a flow of air and fuel into a flame producing combustion burner throughout a range of firing rates is disclosed. The system includes separate valve assemblies for modulating the flow of air and fuel into a burner, a microphone for generating an electrical signal indicative of the intensity of all sounds generated by the combustion flame having a frequency in excess of about 10 Khz, and a controller including a programmable microprocessor electrically connected to both the air and fuel valve assemblies and the microphone. The system further includes a wave guide for remotely acoustically coupling the microphone to the combustion flame in order to isolate the microphone from both heat and corrosive combustion products. Prior to the operation of the system, empirically-derived sound intensities associated with optimum stoichiometric combustion and minimum pollution are entered into the memory of the microprocessor.

Abstract: Disclosed is a system for regulating the efficiency of a combustion process by detecting radiant energy emitted from ash particles entrained in the gas stream exiting the combustion chamber of a boiler or incinerator. The intensity of selected wavelengths of light emitted from the particles is indicative of the temperature of the particles. The change in the intensities of the selected wavelengths of light, and thus of the temperature of the gas stream at the furnace exit, is monitored, and a feedback control mechanism is used to regulate one or more combustion, pollution control, or heat transfer parameters thereby maximizing the thermal efficiency of the combustion process in the boiler or incinerator.

Abstract: A continuous drier for drying a printed web on web-fed rotary printing presses operates during ongoing printing and blanket washing processes with control of the gaseous and vaporous constituents of the ink, solvent, and burner gases. An infrared beam path is installed in the drier to measure concentrations of gas vapors in the drier by an extinction method. The continuous drier process is thus controlled according to the rate of evaporation of volatile constituents. The infrared extinction measurement yields spectral measurements of vapors released by the printing ink during the printing process, or of solvent constituents released during the blanket cleaning process, each according to their characteristic band position and intensity. During the transition from printing to blanket washing, the user obtains an instant picture, based on the band intensities, of the current vapor concentrations.