A pipe which can be shut off by a solenoid valve is provided to feed ammonia gas into {HEAD ~ the mixing chamber} of {TAIL ~ the regeneration system}  
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A pipe which can be shut off by a solenoid valve is provided to feed ammonia gas into { HEAD ~ the mixing chamber } of { TAIL ~ the regeneration system }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH