4. Conclusion
A novel technique, the Scattering-Transmission method, for measuring soot concentration based on the
Scattering integration method and the Extinction theory, has been developed. The new technique need not
pre-required knowledge about the soot average diameter and the soot diameter distribution. Numerical
simulation by using the Mie theory has also infirmed the validity of this technique. Based on the method, a
soot concentration measurement system has been developed. The measurement system uses the 89C2052 as
the MCU and can transfer the on-line measurement data to the monitoring computer. The measurement
system is installed in an exhaust dust of an industrial duct. The experiment results that the Scattering-
Transmission method can on-line measuring the soot concentration.