A method is provided for controlling combustion in a modulating gas furnace. The method includes receiving an indication of a firing rate setpoint for a burner assembly, and applying the firing rate setpoint to first and second continuous functions that map the firing rate setpoint to air-to-fuel ratio and combustion system pressure setpoints. A variable-speed draft inducer blower is set to drive to a combustion system pressure setpoint, and the modulating gas valve is controlled during combustion in the combustion system. In this regard, a combustion system pressure measurement is obtained and applied to an inverse of the first continuous function that outputs an adjusted firing rate for the combustion system pressure measurement. The adjusted firing rate is applied to a third continuous function that maps the firing rate to gas valve position, and outputs a gas valve position to which the modulating gas valve is set.

An edge-banding apparatus is provided and configured to apply an edging strip having a heat activated layer to a substrate or work piece. The apparatus uses localized heat generated from a controlled flame from combustible fuel to apply heat to the edging strip to active the heat activated layer.

A heater comprises a combustion chamber and a jacket extending about the combustion chamber. There is a fan having an output which communicates with the combustion chamber to provide combustion air. There is also a fuel delivery system having a variable delivery rate. A burner assembly is connected to the combustion chamber. The burner assembly has a burner mounted thereon adjacent the combustion chamber. The burner receives fuel from the fuel delivery system. There is an exhaust system extending from the combustion chamber. An oxygen sensor is positioned in the exhaust system to detect oxygen content of exhaust gases. There is a control system operatively coupled to the oxygen sensor and the fuel delivery system. The control system controls the delivery rate of the fuel delivery system according to the oxygen content of the exhaust gases.

A flame arrester for a process device is provided. The flame arrester includes a flame arrester element formed of a first helix having a first axis and a second helix having a second axis, wherein the first axis and the second axis are unparallel. A housing configured to mount to the process device. The flame arrester element is mounted to the housing. A combustion analyzer employing an improved flame arrester is provided along with a method of manufacturing an improved flame arrester for process devices.

Systems and methods operate to infer a fuel composition in a combustion system. The fuel composition may be inferred by receiving measured operating parameters including one or more of fuel data defining fuel characteristics used in combustion within a heater of the combustion system, emissions data defining emission gasses exiting the heater, airflow data defining ambient air being supplied to the heater and airflow rate of the air within the heater. One or more relationships within the measured operating parameters may be identified that result in a list of potential fuel compositions. One of the potential fuel compositions from the list may be selected having sufficient likelihood of resulting in the measured operating parameters as an inferred fuel composition. The output the inferred fuel composition to a heater controller of the combustion system and used for automatic control thereof.

A portable indirect fuel fired heater includes a burner assembly having a fuel burner to deliver fuel from a fuel supply to a combustion chamber of the heater and a combustion air blower to deliver combustion air to the combustion chamber with the fuel for combustion in the combustion chamber to produce exhaust gases. A heat exchanger receives air to be heated in heat exchanging relationship with at least a portion of the combustion chamber. A sensor senses an oxygen level as a partial pressure of oxygen in the exhaust gases. A controller operates an actuator operatively connected to the burner assembly to controllably vary the delivery rate of combustion air and thus vary the ratio of the air and fuel responsive to the oxygen level sensed by the combustion sensor so as to maintain the sensed oxygen level at a prescribed set point level stored on the controller.

A heater comprises a combustion chamber and a jacket extending about the combustion chamber. There is a fan having an output which communicates with the combustion chamber to provide combustion air. There is also a fuel delivery system having a variable delivery rate. A burner assembly is connected to the combustion chamber. The burner assembly has a burner mounted thereon adjacent the combustion chamber. The burner receives fuel from the fuel delivery system. There is an exhaust system extending from the combustion chamber. An oxygen sensor is positioned in the exhaust system to detect oxygen content of exhaust gases. There is a control system operatively coupled to the oxygen sensor and the fuel delivery system. The control system controls the delivery rate of the fuel delivery system according to the oxygen content of the exhaust gases.

A process and apparatus for regenerating a spent acid stream or other stream, such as a spent acid stream or other stream containing sulfur, by decomposing the spent sulfuric acid stream and/or other sulfur-containing streams to recover sulfur dioxide from the stream. Also provided is a process for preparing sulfuric acid from the sulfur dioxide recovered by the apparatus and process.

A burner and methods of using the burner. The burner produces a flame from combustion air and fuel gas. Flue gas, also produced, can be withdrawn and recycled to the burner. A cooling or condition gas, such as ambient air, may be mixed with the flue gas to reduce its temperature. The burner may also utilize a stage injection so that a portion of the produced flue gas is recycled internally.

A system is provided with a turbine combustor having a first diffusion fuel nozzle, wherein the first diffusion fuel nozzle is configured to produce a diffusion flame. The system includes a turbine driven by combustion products from the diffusion flame in the turbine combustor. The system also includes an exhaust gas compressor, wherein the exhaust gas compressor is configured to compress and route an exhaust gas from the turbine to the turbine combustor along an exhaust recirculation path. In addition, the system includes a control system configured to control flow rates of at least one oxidant and at least one fuel to the turbine combustor in a stoichiometric control mode and a non-stoichiometric control mode, wherein the stoichiometric control mode is configured to change the flow rates and provide a substantially stoichiometric ratio of the at least one fuel with the at least one oxidant, and the non-stoichiometric control mode is configured to change the flow rates and provide a non-stoichiometric ratio of the at least one fuel with the at least one oxidant.