GB593778A - Catalytic conversion of oils - Google Patents

Abstract

<PICT:0593778/III/1> <PICT:0593778/III/2> In processes for the catalytic conversion of hydrocarbons (including cracking, reforming, hydrogenation, dehydrogenation, isomerisation, polymerisation, desulphurisation) of the kind employing a fluidised catalyst system, improved control of the coke deposition on the catalyst and thus of the heat produced in the regeneration are obtained by feeding and simultaneous conversion of two stocks differing in their refractory nature, a higher boiling less refractory fraction through line 23 into the upper portion of the converter 17 and a lower boiling more refractory fraction through line 7 into the bottom of the catalyst bed. The conversion plant comprises converter 17, regenerator 20, products fractionator 29 and associated preheating furnaces 21, 22 and catalyst standpipes 18, 19, 24, 25. The respective fractions for conversion are obtained by stripping the crude in a tower 3 of gasoline and naphtha which are separated in tower 5. The partly reduced crude is heated in furnace 15 and fractionated in tower 9 to separate heavy naptha, light and heavy gasoil fractions through lines 10, 11, 12 respectively and a reduced crude is recovered as bottoms and passed through a further coil in furnace 15 the products being flashed in a tower 14 at temperatures of 700-840 DEG F. and under a pressure of 100 mm. with slight cracking if desired to recover a heavy flashed condensate which constitutes the less refractory stock fed through line 23 while the naphtha collected at bottom of tower 5 constitutes the more refractory stock fed through line 7. Gasoline is recovered overhead from tower 29 while a heavy aromatic fraction is collected through line 35 and fed to tank 41 where it is mixed with the tarry residues from flasher 14 to constitute a stable fuel oil. The fractionation may be controlled to separate more or less refractory fractions differing in respect to (a) molecular weight (b) content of nitrogen bases (c) naphthenic and olefinic content (d) paraffinic and olefinic content (e) aromatic and paraffinic content. The reactor, Fig. II, is adapted to converting two stocks simultaneously by providing an upper manifold 46 for the less refractory stock and a lower manifold 45 for the more refractory stock.ALSO:In processes for the catalytic conversion of hydrocarbons (including cracking, reforming, hydrogenation, dehydrogenation, isomerization, polymerization, desulphurization) of the kind employing a fluidised catalyst system, improved control of the coke deposition on the catalyst and thus of the heat produced in the regeneration and simultaneous conversion of two stocks differing in their refractory nature, are obtained by feeding the higher boiling less refractory fraction through line 23 into the upper portion of the converter 17 and the lower boiling more refractory fraction through line 7 into the bottom of the catalyst bed. The conversion plant comprises converter 17, regenerator 20, products fractionator 29 and associated preheating furnaces 21, 22 and catalyst standpipes 18, 19, 24, 25. The respective fractions for conversion are obtained by stripping the crude fed through line 1 to the mid-point of tower 3 of gasoline and naphtha which are separated in tower 5. The partly reduced crude is heated in furnace 15 and flashed in tower 9 to separate heavy naphtha, light and heavy gas oil fractions recovered through lines 10, 11, 12 respectively and a reduced crude is recovered as bottoms and passed through a further coil in furnace 15, the products being flashed in tower 14 at temperatures of 700-840 DEG F. under a pressure of 100 mm. with slight cracking if desired to recover a heavy flashed condensate which constitutes the less refractory stock fed through line 23 while the naphtha collected at bottom of tower 5 constitutes the more refractory stock fed through line 7. Gasoline is recovered <PICT:0593778/IV/1> <PICT:0593778/IV/2> overhead from tower 29 while a heavy aromatic fraction is collected through line 35 and fed to tank 41 where it is mixed with the tarry residues from flasher 14 to constitute a stable fuel oil. The fractionation may be controlled to separate more or less refractory fractions differing in respect to (a) molecular weight, (b) content of nitrogen bases, (c) naphthenic and olefinic content, (d) paraffinic and olefinic content, (e) aromatic and paraffinic content. The reactor, Fig. II, is adapted to converting two stocks simultaneously by providing an upper manifold 46 for the less refractory stock and a lower manifold 45 for the more refractory stock.