N₂O Decomposition
N₂O

Nitrous Oxide (N₂O) is formed and emitted into the atmosphere in significant concentrations from several industrial chemical processes, in particular the production of nitric acid, caprolactam and adipic acid. N₂O is a strong greenhouse gas (GHG) and has a global warming potential of 310 times higher than CO2. In the Clean Development Mechanism (CDM) under the Kyoto Protocol, N₂O is included as a GHG and N₂O reduction projects can be used to generate tradable carbon credits and financial revenues.

CRI N₂O Decomposition Technology

The CRI N₂O Abatement Technology (C-NAT) is a catalytic technology for the decomposition of nitrous oxide (N₂O) in chemical streams.

The CRI technology is a direct N₂O decomposition process that does not require the addition of any reducing agent or other reactant. N₂O destruction of 98% or higher can be achieved over a range of temperatures and pressures. No undesirable byproducts are formed.

The catalyst does not form other oxides of nitrogen such as NO or NO2.

Applications for the CRI N₂O abatement technology include the tail gas from nitric acid, caprolactam and adipic acid plants. The CRI N₂O decomposition technology is highly effective under the range of operating conditions and tail gas compositions typically found in such plants.

N₂O Abatement System

The CRI N₂O destruction catalyst is in the form of tri-lobed extrudates.  The catalyst is contained in a reactor module which is based on the Lateral Flow Reactor (LFR) principle.  The LFR is a packed-bed type reactor in which the catalyst is contained in thin layers between gas channels.  The flue gas is flowing laterally through the catalyst layers which makes possible the most efficient utilization of the catalyst and which minimizes pressure drop even at high space velocities.

The catalyst modules are placed in a reactor house, typically in a single layer, which provides support to the modules as well as sealing around the modules to insure all of the gas passes through the catalyst bed.  The reactor house can be atmospheric or the catalyst modules can be incorporated inside of a pressure vessel for high pressure applications.  The reactor house can be designed for vertical up or down flow or horizontal flow.

The CRI N₂O process does not require the addition of any reducing agent or other reactant.

The CRI N₂O catalyst is stable in the presence of NOx (NO + NO2) and ammonia (NH3) so that it can be located upstream or downstream of a selective catalytic NOx reduction (SCR) system.

If the tail gas temperature is lower than the optimum temperature range of the CRI technology, flue gas reheat with associated heat recovery can be installed upstream of the catalyst reactor to optimize process economics.