PetroChina Develops Co-cracking of C4with Light Ends to Broaden the Source of Steam Cracker Feed

The PetroChina’s Petrochemical Research Institute has been granted a Chinese invention patent on the technology for manufacture of ethylene through steam cracking. This technology aims to co-cracking of alkane-rich light ends in admixture with C4fraction to increase the ethylene yield in the C4byproducts to broaden the source of steam cracker feedstocks which has improved the feedstock structure and the overall product quality.

It is told that this technology has avoided such setbacks as the less than 18% of ethylene yield upon pyrolysis the single C4fraction, severe coking in pyrolysis furnace tubes and shortened pyrolysis furnace operating cycle. Thanks to the stimulus action of alkanes to pyrolysis of C4fraction, the ethylene yield can be increased by 25%—26% (converted to C4basis), and the ethylene yield obtained from C4fraction during co-cracking process can be increased by 7%—8% as compared to that obtained during pyrolysis of the single C4fraction to harvest apparent economic benefits. Meanwhile the researchers have been engaging in selection of reasonable blending ratio between C4fraction and light ends and optimal process parameters to remarkably increase the yield of ethylene, propylene and butadiene obtained from pyrolysis of C4fraction.