Download Tolling Feeds in Olefin Processing to Improve Yields

The numerous types of feeds are being cracked in pyrolysis furnace of olefin plant. These feeds are either liquid i.e. propane, butane naphtha etc or gaseous feed i.e. ethane. There are mixed cracker who operate on the mixture of 50% liquid & 50& gas feed i.e. Propane & ethane in 50% ratio of feedstock. The yield of desire olefin products from liquid, mixed and gaseous feed are varies significantly as per the feedstock. The Furnace Yield of desire products i.e. ethylene & propylene plays a very vital role in distribution of olefin products. The production cost of olefin product from liquid feed is much higher than mixed feedstock. The production cost of olefin product from ethane feed cracker is much cheaper than the mixed feed cracker. If two mixed feedstock crackers agreed to toll (exchange) their feedstock in such ways that one cracker will operate on 100% propane and other will operate on 100% ethane. Then, products & by-products delivered from these two crackers will be shared as per the feedstock ratio. The tolling (exchange) of feedstock will provide the flexibility in operation and improvement in the Yield to individual cracker. A study has been carried out that tolling of feed will reduced the overall production cost of olefin products in comparison with mixed feedstock and improves the Yield. The improved yield will increase the production of olefin product & by-products. These papers will emphasis, first how the tolling of feedstock will reduce the product cost of olefin products. Moreover, tolling of feed will improve the yield without any extra feedstock. This paper will also provide the guide line, how to toll the feedstock between two mixed feed crackers without affecting their olefin production. The tolling between the two mixed feed crackers is linked with crude oil price. It is very difficult for olefin producer to compete in the petrochemical market with this vibrant & highly fluctuating crude oil price. Secondly it will provide the bit additional by-products, which can be process further in downstream process unit to generate further revenue. This scenario will provide competitive profit margin in comparison to other mixed feed olefin process unit, who are not able to exchange the feed.