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Experimental and Numerical investigations are conducted in this work to mitigate self-sustained thermoacoustic oscillations in standing-wave Rijke-type thermoacoustic systems. 2D numerical simulations of a propane-burnt combustion system are first conducted to gain insight on the effect of a secondary heat source on damping flame- exited thermoacoustic oscillations. Constant-temperature heating bands are placed at the downstream of the Rijke-type combustor. It is shown that the flame-sustained pressure oscillations are dramatically dampened, depending on the surface temperature of the heating bands. Experiments are then conducted. It is shown that placing an electrical heater at a proper position can lead to heat-driven acoustic oscillations being completely mitigated. And the standing-wave Rijke-type thermoacoustic system is stabilized.

Nowadays, industries have been using combustion system as one of energy supply in their utility system. However, incomplete combustion process often takes place in the process, which resulted in several disadvantages for the industry such as less energy efficiency, higher CO emission and higher production cost. The aimed of this study was to understand characteristics and increasing combustion efficiency in fuel preheating system technology and to find out the effect of various initial temperature of LPG to combustion efficiency and CO emission. Results showed that increasing initial temperature of LPG from 28 °C to 50 °C would raise efficiency of the burner up to 6.75% while CO emissions decreased 49.06%. Furthermore, if the temperature increased up to 100 °C the burner efficiency would raise significantly and CO emissions considerably decreased.

The setting of furnace temperature in combustion system of reheating furnace at rolling mill is an important parameter in the production process. Variety of some factors such as furnace heating capacity, steel thermal stress, production rhythm etc. directly affects the setting of furnace temperature, it is an industry problem. This article analysis about how the above mentioned factors affect the furnace temperature setting, and mainly focus on dynamic setting strategy of furnace temperature so as to fit fluctuation of production rhythm through theoretical analysis on the energy balance of billet heat transfer in the furnace. This strategy has been verified by production and experiment, and matches with the related data.

Doosan Power Systems has adopted an evolutionary approach to the design and implementation of OxyCoal™ technology combining well proven and commercially available components with state-of-the-art advances in technology, and is leading a number of UK Government supported collaborative projects that are developing oxyfuel combustion technology. The “Demonstration of an Oxyfuel Combustion System” OxyCoal 2 project aimed to demonstrate an oxyfuel combustion system of a type and size (40MW t ) applicable to new build and retrofit advanced supercritical oxyfuel plant. Following conversion to oxyfuel firing, the Clean Combustion Test Facility (CCTF) became the world’s largest demonstration facility of an oxyfuel combustion system, and since the official opening on 24th July 2009 a test programme has been successfully undertaken to demonstrate the full-scale Doosan Power Systems first generation 40MW t OxyCoal™ burner on air and oxyfuel firing, achieving safe and stable operation across a wide operational envelope and CO 2 flue gas concentrations in excess of 75% v/v dry, and up to 85% v/v dry. The OxyCoal 2 project is discussed in the paper and results from testing the full-scale 40MWt OxyCoal™ burner firing bituminous coal in both air and oxyfuel firing operation are presented.

Doosan Babcock is aiming to develop a competitive oxyfuel firing technology suitable for full plant application post 2010, and is taking a phased approach to the development and demonstration of oxyfuel technology. Doosan Babcock is leading a number of UK Government supported collaborative projects that are developing oxyfuel combustion technology. The “Fundamentals and Underpinning Technologies” project aims to develop a competitive oxyfuel firing process based on the integration of well proven and innovative power plant design components, addressing critical technology gaps such as combustion fundamentals, furnace design and operation, novel flue gas purification technologies and generic process issues. The “Demonstration of an Oxyfuel Combustion System” project aims to demonstrate an oxyfuel combustion system of a type and size (40MW t ) applicable to new build and retrofit advanced supercritical boiler plant. These two projects are discussed in the paper and preliminary results from pilot-scale testing undertaken in the first of these are presented.