DEVELOPMENT OF A NOVEL PEAK-SEEKER CONTROL-SYSTEM SUITABLE FOR WASTE INCINERATORS

Gas-sampling systems have shown an inability to respond to the rapid c hanges in conditions normally experienced in solid-waste incinerators, and this has led to control problems. Even in large municipal inciner ators, oxygen deviations take place in timescales comparable to the ga s-sampling lag. The spectroscopy-based system-the peak-seeker-describe d here has the potential to solve these problems. The research, design and development of a computerised peak-seeker control system that may be applied to the secondary tone of a waste incinerator is also descr ibed. The system relies on the measurement of flame radiation in respo nse to a sinusoidal air/fuel ratio modulation. Tests made on a laborat ory-based oil furnace include multisine system characterisation and th e effect of fuel flow on the Control point. Novel developments to the peak-seeker have been made which allow more information to be gained o n the operating point. The incorporation of the peak-seeker into a com mercial incinerator unit is also described, making use of a fluidic va lve (no moving parts) to improve life.