An oxy-combustion firing configuration, process, and apparatus can reduce the consumption of oxygen and fuel in an oxy-fuel combustion processes. Processes in accordance with the present invention include operation of an automated logic control device which controls an oscillating valve and controller. The valve and controller are used to oscillate the fuel and/or oxygen supplied to individual burners in a furnace. The oscillating parameters, such as frequency, amplitude, duty cycle, and phase difference between individual burners and their stoichiometry ratio are set to initiate preferable oxy-combustion in that furnace. Selective burner placement in the furnace enables the formation of deflagration zones which can provide very intense heating and complete combustion.

The burners of a fuel-fired system are controlled by means of a feedback control system for temperature control. The control system comprises temperature measuring means, a controller for temperature control, final burner controlling means translating the output from the controller into an appropriate burner input rate, and a digital central processing unit determining pulse spacing (t.sub.ps), pulse duration (tON) and pulse separation (tOFF). A minimum pulse spacing (.sup.t ps.sub.min), being the sum of the minimum pulse duration (tON.sub.min) and the minimum pulse separation (tOFF.sub.min), is present and used as an input rate reference value. Using the input rate reference value for the minimum pulse spacing, the burner input rate is controlled in accordance with process requirements by varying pulse spacing (t.sub.ps) through varying pulse separation or pulse duration. For input rates lower than the input rate reference value, pulse separation is increased, and for input rates higher than the input rate reference value, pulse duration is increased with pulse separation remaining the minimum pulse separation. The feedback control system substantially improves the rangeability of burners controlled by ON-OFF control systems, minimizing pulse spacing and achieving correspondingly rapid response.

A process for combustion in an industrial furnace (1), using at least one burner (2; 3) supplied with combustible (4) and combustion supporting (5) fluids. The flow rate of at least one of the fluids is pulsed at a frequency comprised between 0.1 and 3 Hz. There is provided in the furnace (1) at least one pair of two burners (2A, 2B; 3A, 3B) disposed substantially confronting each other; and the fluid of the burners of a pair is pulsed in offset phase from one burner to the other. The frequency of pulsation is between 0.1 and 1 Hz. The flow rates of fluids are substantially identical for each burner (2A, 2B; 3A, 3B) of the pair. The power of the pair of burners is greater than 300 KW.

A burner apparatus comprising: a burner plate on which fuel gas is ignited, a thermal sensor which generates an output voltage in response to the combustion of the fuel gas so as to detect an air component of the fuel gas, means for causing the output from the thermal sensor to correspond to the quantity of combustion on said burner plate, and a safety circuit which stops combustion on said burner plate when the output of the thermal sensor displaces from a magnitude within a certain range.

Pressure variation of combustion noise is detected by a microphone set in a combustion chamber, and the pressure propagation characteristic for the path from the gas flow control valve to the microphone is identified while the combustion apparatus is operating, and then an adaptive control is made using one signal detected by an microphone and the other signal produced by passing the signal of the microphone through a filter, and then a corrected anti-phase signal of a combustion noise is computed by the coefficient updating circuit, and the computed result is inputted to a gas flow control valve.