Performance study on the dust removal from ritual money incinerator vent gases by a spray chamber
A 20 kg/hr ritual-money combustion chamber and a 20 Am3/min (@35oC) wet scrubber were setup for performance tests on the removal of TSP (total solid particulates) from the combustion flue gas. Test results indicate that (1) TSP in the flue gas ranged from 93-157 (avg. 126) and 127-182 (avg. 157) mg/m3 (@35oC) at gas drawing rates (QG) of 13.1 and 26.3 m3/min (@35oC), respectively, and ritual-money combustion rates of 14.2-16.3 (avg. 15.3) kg/hr. The lower gas drawing rate gave lower TSP concentrations in the flue gas. TSP removal efficacy varied linearly with the liquid scrubbing rate (QL) and a 70% TSP removal was achieved at a QL of 60 L/min which is equivalent to a scrubbing-liquid intensity of 4.0 L/m2.s over the scrubber cross section. (2) Visual smoke intensity in the exit of the scrubber chimney was not apparent with a combustion rate of 16 kg/hr, scrubbing intensity of 4.0 L/m2.s, and gas drawing rates of 13.1 and 26.3 m3/min. (3) Scrubbing water consumptions of 1.2-2.4 L were estimated for a combustion of 1 kg ritual money. (4) Pertinent design parameters of a scrubber for 70% TSP removal from the flue gas are (a) liquid/gas ratio (QL/QG) = 3-6 L liquid/(m3 gas @30oC); (b) superficial gas velocity over the scrubber cross section (UG) = 0.6-1.2 m/s; (c) superficial liquid velocity over the scrubber cross section (UL) = 0.004 m/s; and (d) a gas-liquid contacting length of 0.70 m. Results also show that the combustion exit gas odor concentration (D/T, dilution times to threshold) could be removed from 309 to 232 by the scrubber at operation conditions of QG = 13.1 and 26.3 m3/min, and QL = 60 L/min. Results also show that parts of CO2, CO, and NO could be removed by the scrubbing liquor, and there was no significant removal for NO2 and SO2 by the scrubber. By spraying KClO3 on a homemade wood pulp ritual money at a dosage of 3 wt.%, it shows that it burned more rapidly and with more smoke emission than a non-sprayed sample. Experiments also show that FeCl3 (15mg/L) was a satisfactory coagulant for enhancing the coagulation and sedimentation of the suspended solids (SS) in the wasted scrubbing liquor (known as Gray water). By the coagulant, SS in the Gray water with a pH of 7.0 could be removed from 100 to < 10 mg/L. XRD (X-Ray Diffraction) examination of a bottom ash sample indicates that the ash has an elemental composition of O, Na, Al, and Si of 49.9, 11.8, 23.8, and 15.1%, respectively. SEM (Scanning Electron Microscope) analysis indicates that the collected fly ash and the bottom one have particle sizes of 20-110 (mostly 45-60 nm) and 50-300 (average 250) nm, respectively.
Advisor:none; none; none
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:ritual money combustion air pollution control spray type flue gas scrubber
Date of Publication:07/05/2007