Plasma technology to remove NO_x from off-gases

Abstract

Operation of marine diesel engines causes significant emission of sulphur and nitrogen oxides. It was noticed worldwide and the regulations concerning harmful emissions were introduced. There were several solutions elaborated; however, emission control for both SOx and NOx requires two distinctive processes realized in separated devices, which is problematic due to limited space on ship board and high overall costs. Therefore, the electron beam flue gas treatment (EBFGT) process was adopted to ensure the abatement of the problem of marine diesel off-gases. This novel solution combines two main processes: first the flue gas is irradiated with electron beam where NO and SO2 are oxidized; the second stage is wet scrubbing to remove both pollutants with high efficiency. Laboratory tests showed that this process could be effectively applied to remove SO2 and NOx from diesel engine off-gases. Different compositions of absorbing solution with three different oxidants (NaClO, NaClO2 and NaClO3) were tested. The highest NOx removal efficiency (>96%) was obtained when seawater-NaClO2-NaOH was used as scrubber solution at 10.9 kGy dose. The process was further tested in real maritime conditions at Riga shipyard, Latvia. More than 45% NOx was removed at a 5.5 kGy dose, corresponding to 4800 Nm3/h off-gases arising from ship emission. The operation of the plant was the first case of examination of the hybrid electron beam technology in real conditions. Taking into account the experiment conditions, good agreement was obtained with laboratory tests. The results obtained in Riga shipyard provided valuable information for the application of this technology for control of large cargo ship emission.

Advances in electron beam technology for environmental and biotechnological applications at Fraunhofer FEP

“…To remove not only SOX and PM but also NOX and VOC with a high efficiency, Fraunhofer FEP, as a part of the ARIES collaboration, worked on the development of a hybrid electron accelerator system for the treatment of marine diesel exhaust gases. Under real field conditions a Proof of Concept could show that a removal of not only SOX and NOX but also VOC is possible in one hybrid process by combining an EB treatment (provided by two linear area beam generators) with a seawater scrubbing unit [6][7][8]. As in waste water treatment, the electron interaction causes the generation of free radicals in the flue gas.…”

Simulation of a Multistaggered Baffle Scrubber to Enhance the Efficiency of Simultaneous Desulfurization and Denitrification

“…Increased environmental consciousness and worldwide sustainable development have led to increasingly strict industrial emission requirements. Currently, the methods widely utilized in the industrial emission treatment include the optimized combustion technology, , selective catalytic reduction (SCR), , adsorption, absorption, − and electron beam technology. , However, each of these methods has limitations owing to the various requirements for gas management under different industrial settings, operating conditions, and running costs …”