Page 62 - Industrial Plants

Fig ure 5 -
Performances on WTE
flue gas after the
fabric filter: reduction
of the PM
concentration (left)
and abatement
efficiency (right)

2 mg/Nm . The recirculation was introduced after the particles and acids removal at low temperatures makes
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fabric filter unit and reinject the gas before the fabric the WES system particularly suitable as a revamping of
filter, to allow compliance of the emissions and preserve low-efficiency wet scrubbers for the removal of fine,
the representativeness of the emission control system submicronic and ultrafine particles.
placed before the plant stack. The WES was installed After the successful completion of the pilot-scale tests,
as a retrofit for the abatement of the submicronic Boldrocchi company will be ready to commercialize the
particles that were around 2-5·10 #/cm , consistently WES technology for industrial application in 2022, with
3
5
with the low particulate emissions at the chimney of extension to other sectors in the following years. In
incinerators equipped with a similar exhaust gas particular, Boldrocchi is part of a joint venture with
cleaning train. The treated gas stream was 4500 Nm /h other companies for the building, installation and
3
and the liquid-to-gas ratio was slightly below 1 kg/kg. experimentation of a pilot-scale WES unit for marine
diesel engine exhaust gas treatment, that will be put in
Despite the very low particles concentration and the operation in the first half of 2022.
very low liquid-to-gas ratio, which reduce the removal
efficiency, the WES unit allowed reducing the emissions “Following the successful completion
by more than 80%, for PM , 75% for PM , and 60% of the pilot-scale tests, Boldrocchi
10 2.5
for PM , with a reduction of particles number above will be ready to commercialize
1
70% for particles finer than 50 nm (Figure 5). the WES technology for industrial
Due to the low concentration of pollutants (PM and applications in 2022
acids) at the WES inlet, the system operated in a
closed-loop mode, with a total water consumption
below 0.02 kg per kg of treated gas. Besides, the (Endnotes)
maximum power consumption for the loading WES 1 Di Natale, Carotenuto C., D’Addio L., Jaworek A., Krupa
units was 25 mWh/Nm and the pressure drop was of A., Szudyga M., et al., Capture of fine and ultrafine
3
0.5 mbar. particles in a wet electrostatic scrubber, J. Environ.
Chem. Eng. 3 (2015) 349–356. doi:10.1016/j.
Tests will be performed in the next months to further jece.2014.11.007.
explore the performances of the WES unit for this 2 Di Natale F., Carotenuto C., Manna L., Esposito M., La
application, thanks to better integration with the Motta F., D’addio L., et al., Water electrified sprays for
existing fabric filter unit aimed to optimise the particle emission control in energy production processes, Int. J.
capture. HEAT Technol. 34 (2016) S597–S602. doi:10.18280/
ijht.34S256.
3 Di Natale F., Carotenuto C., Caserta S., Troiano M.,
Conclusions Manna L., Lancia A., Experimental evidences on the
chemi-electro-hydrodynamic absorption of sulphur
WES will find application in many industrial sectors, dioxide in electrified water sprays, Chem. Eng. Res. Des.
where low concentrations of submicronic and ultrafine 146 (2019) 249–262. doi:10.1016/j.cherd.2019.04.006.
particles are required. Low energy consumption and 4 F. Di Natale, C. Carotenuto, A. Parisi, A. Lancia,
low-pressure drops allow an easy integration within Absorption of sulphur dioxide by electrosprayed droplets,
existing gas cleaning trains either for newbuilds and Can. J. Chem. Eng. 98 (2020) 1989–1997. doi:10.1002/
retrofit conditions. Furthermore, the high capacity of cjce.23821.

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