초록 ▼

A method is disclosed for the addition of an oxygen-containing gas under certain defined process conditions, to an off-gas stream derived from an FCC regenerator which is operated in a partial mode of combustion. The off-gas from the regenerator contains 1-6% CO by volume and at least 300 ppm nitrog

A method is disclosed for the addition of an oxygen-containing gas under certain defined process conditions, to an off-gas stream derived from an FCC regenerator which is operated in a partial mode of combustion. The off-gas from the regenerator contains 1-6% CO by volume and at least 300 ppm nitrogen compounds comprising NH3 and HCN. Without the addition of an oxygen-containing gas, roughly 25 percent of the NH3 and HCN are converted to NOx in downstream CO boilers. A preferable method of this invention comprises the addition of heated air (20% O2) into the regenerator off gas to produce an off gas stream having a temperature of 1260°F. to 1500°F.

대표청구항 ▼

A process for the reduction in the amount of nitrogen compounds comprising (ammonia) NH3 and (hydrogen cyanide) HCN present in a regeneration off gas stream prior to said stream\s passage to a CO boiler having an amount of said nitrogen compounds, wherein the regeneration off gas stream is derived f

A process for the reduction in the amount of nitrogen compounds comprising (ammonia) NH3 and (hydrogen cyanide) HCN present in a regeneration off gas stream prior to said stream\s passage to a CO boiler having an amount of said nitrogen compounds, wherein the regeneration off gas stream is derived from a regenerator operating in a partial mode of combustion to produce said nitrogen compounds and at least 1% CO in said stream, said process comprises adding an amount of an oxygen-containing gas consisting essentially of air or oxygen to said off gas stream to produce a gas stream having a temperature of 1260°F. to 1400°F. for a period of time sufficient to convert said nitrogen compounds to NOx and N2. In a process for the regeneration of a catalytic cracking catalyst in a regeneration zone operated at regeneration conditions sufficient to result in 1]a partial mode of regeneration defined by a CO content greater than 1% CO and 2]a quantity of nitrogen compounds including NH3 and HCN, the improvement which comprises adding an amount of an oxygen-containing gas consisting essentially of air or oxygen to said off gas to produce an off gas stream having a temperature of about 1260°F. to about 1400°F. sufficient to convert said nitrogen compounds to NOx and N2.