초록

A system is disclosed for monitoring the concentration of gaseous ammonia in flue gases by simultaneously measuring the temperature and optical transmission of a flue gas-ammonia mixture.

대표청구항 ▼

A system for monitoring gaseous ammonia concentration in flue gases comprising: (a) a first laser means which emits radiation at about 927.30 cm-1 which is selectively absorbed by ammonia but not spectrally selectively absorbed by any substance in said flue gases said flue gases including more than

A system for monitoring gaseous ammonia concentration in flue gases comprising: (a) a first laser means which emits radiation at about 927.30 cm-1 which is selectively absorbed by ammonia but not spectrally selectively absorbed by any substance in said flue gases said flue gases including more than about 10% CO2 and more than about 8% H2O; (b) a second laser means which emits radiation which is not spectrally selectively absorbed by ammonia or by said flue gases; (c) means to measure the temperature of said flue gases; (d) means to modulate the output radiations of each of said first and second laser means; (e) means to measure each of the powers of the output radiations of said first and second laser means; (f) means to combine and direct a portion of each of said output radiations onto a common optical path through said flue gases; (g) means to measure the powers of each of said portion of said radiations after passing through said flue gases; (h) means to electronically measure the absorption of said radiations; and (i) means for computing the absolute concentration of said ammonia from said measurements of said absorption of said radiation and said measurements of said temperature.