Ettlingen, April 2005
In a production plant, 72 kg/h of NH3 containing
portions of a highly inflammable constituent must be drawn off and cleaned to
comply with the values required by TA-Luft. The highly inflammable constituent
is contained in the gas in the form of drops and is not electrically
conductive.
This application is particularly characterized by the high
explosion protection requirements.
In accordance with ATEX, the gas
chamber inside the scrubber belongs to category II 1G (zone 0), and the
ambiance belongs to II 2G (zone 1).
GEA Jet Pumps have designed a
two-stage process for this application based on the standard compact gas
scrubber series.
The exhaust gas is drawn off by the jet scrubber and
is cleaned to a large extent by chemical absorption in diluted sulphuric acid.
The compliance with the specified limiting values is then ensured in the
downstream counterflow column (2nd stage) by fine adsorption.
The
entire plant has been designed for the operation in Ex-zone 0 and has been
certified and homologated in a separate official acceptance procedure by the
EXAM in Bochum, Germany.
The jet scrubber tube and the motive nozzle
are made of material PP-EL. The gas scrubber is made of PP, is installed on a
base frame made of galvanized steel and is equipped with a circulation pump and
the necessary measuring and control equipment for pH value, level, density and
temperature.