Chanrit Punkluaymai. The design and construction of a control unit for dust and metal fumes from a melting bronze furnace . Master's Degree(Industrial Hygiene and Safety). Mahidol University. : Mahidol University, 2007.
The design and construction of a control unit for dust and metal fumes from a melting bronze furnace
Abstract:
A small foundry usually produces air pollution causing problems in the
working area and community. The study aimed to remove the total dust emitted from
a melting bronze furnace and decrease total dust concentration based on the
principles of particle control unit construction and the budget of small a foundry.
This study started with preliminary sampling, where total dust concentration
average and particle size distribution were determined. Those results were considered
for the design and construction of a local exhaust ventilation system and a packed bed
scrubber type countercurrent to remove total dust from the melting bronze furnace.
The local exhaust ventilation system was constructed by galvanized steel for drawing
total dust emitted from the melting and pouring bronze process. Then, total dust was
transferred into the packed bed scrubber type countercurrent flow, afterward clean air
would be released to atmosphere. The packed bed scrubber was constructed by
stainless steel, with the dimensions 1.97 x 1.97 x 7.22 ft and separated into 3 parts:
bottom, middle and top. The selected packing was square rings, which had a surface
area of 58 ft2/ft3 and density of 3.4 kg/ft3. The square rings filled the middle part of
the scrubber, packing height 0.67 ft/stage, in 3 stages. The flow rate of liquid in the
packed bed scrubber was 90 l/m. The testing system was done in order to measure and
adjust parameters following Wiwat and Kanaoka’s (1985) [9] recommendation after
the design, construction and installation. The sample collection was stack sampling of
5 samples by isokinetic principle at 2 positions (inlet and outlet duct). The measured
parameters were gas velocity 222-287 fpm, gas flow rate 862-1,114 cfm, duct velocity
1,951-2,521 fpm, pressure drop 0.1167-0.1500 ft.H2O and liquid/gas ratio 61.2-79.1
l/1,000ft3. The results of total dust concentration at inlet and outlet duct were 13.24-
14.25 mg/m3 and 6.55-8.62 mg/m3, respectively. The packed bed scrubber type
countercurrent flow had a removal total dust efficiency average (η) of 44.00% and
removal of total dust larger than 2 μm efficiency average (η ≥2μm) of 89.96%.