Evaluation of Plastic Waste Management in Thailand Using Material ...

silicate clay, natural clay, metal-loaded catalyst and hydro-cracking catalyst to reduce the
burning time and temperature required for combustion.
Normally this system can generate 5,000 liters of crude oil per day, but plastic wastes must
be very clean and are not contaminated by any contaminant. In fact, plastic bags from
landfill are dirty and contain a lot of contaminants and moisture content, so this pyrolysis
process can generate only 3,500-4,000 liters of oil per day. At the first time, the reactor is
initially heated by burning LPG at 480-520 ºC to melt the plastic bags, and then the plastic
bags are fed into the reactor which has seven paddles. This reactor has a fixed-bed like a
pan. Plastic bags are melted and mixed by paddles.
Drum screen for heavy material
separation
Air separation machine for
heavy material sorting
Weighting scale
Figure C-17 Sorting Unit
There are four movement patterns for paddles such as left to right, right to left, twist and
turn, and up and down. Plastic bags are converted from liquid into gas, and then the gas
will be condensed at 250-270 ºC to generate crude oil. Some uncondensed gases are reused
for burning in the reactor again in order to reduce the high amounts of LPG required. This
reactor is operated for 24 hours. Moreover, some unusable and uncondensed gases are
burnt before releasing into the atmosphere.
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Conveyer belt for manual
sorting
Conveyer belt for feeding
plastic waste to air separation
Sorted plastic waste