It is predicted that by 2005, the annual growth rate of propylene demand will be 5.6%, which is higher than the annual growth rate of ethylene demand of 3.7%. It is expected that the demand for propylene will reach 82 million tons by 2010. At this rate of increase, by 2004, there will be an increase in production capacity of 15.5 million tons. The global propylene production capacity will increase from 59.30 million tons in 2000, 62 million tons in 2001 to 68 million tons in 2002, 74 million tons in 2004, and 82 million tons in 2008. At present, 66% of the world's propylene comes from the by-products of steam cracking to produce ethylene, 32% comes from refinery catalytic cracking (FCC) to produce gasoline and diesel by-products, and a small amount (about 2%) from propane dehydrogenation and ethylene-butenes translocation. The reaction is obtained. Various technologies for increasing propylene production are being developed and applied. (1) Steam cracking and increasing propylene production In the process of steam cracking ethylene, the yield of propylene under different raw materials and operating conditions is not the same. In general, the propylene yield of various raw materials increases as the relative molecular mass of the raw material increases. The production of ethylene from naphtha, gas oil, and propane, each producing 1 ton of ethylene, produces 0.4 to 0.6 tons of propylene by-product; ethane is used as the raw material to produce 1 ton of ethylene, and only by-product 0.04 to 0.06 tons of propylene. (2) Improved catalytic cracking technology for increasing propylene production According to the estimated growth rate of propylene demand of 5.6% over the next few years, existing refineries must increase production by 4.1 million tons per year in order to meet the demand of propylene in the petrochemical industry. This will mainly come from catalytic cracking units. . The petrochemical industry's demand for refinery catalytic cracking (FCC) to increase propylene production has enabled petrochemicals to be more closely integrated with oil refining. Bean Leatherette Cushion,Round Stools,Recycled Leather Stool,Breathable Leather Stool SHAOXING CITY JINYAO TEXTILES CO.,LTD , https://www.jinyaotextile.com
In order to meet the demand for naphtha cracking to produce more propylene, the Japan National Materials and Chemical Research Institute and the four petrochemical companies have jointly developed a naphtha cracking process that increases propylene production and reduces energy consumption. The traditional 0.6:1 increased to 0.7:1. Compared with conventional thermal cracking, the process uses a molecular sieve-supported ruthenium catalyst in a fixed bed. Laboratory validation tests have shown that the process can increase the propylene yield of ethylene to 61%, while the usual steam cracking is 50%. A feasibility study of a 3,000-ton/day installation indicates that the operation can be performed at pressures of about 650°C and 0.1 to 0.2 MPa, whereas conventional installations need to be performed at about 820°C and 0.1 to 0.2 MPa. The unit cost is similar to conventional cracking, but energy consumption is reduced by about 20% due to operation at lower temperatures. The process can also be used to retrofit existing naphtha crackers.
A typical FCC unit produces about 0.03 to 0.06 tons of propylene per ton of gasoline produced. In recent years, the FCC unit has developed a number of process technologies for increasing the production of propylene, including: the DCC process of the Sinopec Research Institute of Petroleum and Chemicals (RIPP), the Maxofin process of Kellogg-Brown-Rotter (KBR), the Superflex process, and UOP. The PetroFCC process, the Romacs SCC process. Figure 1. Shows a comparison of the yields of propylene produced by steam cracking, conventional FCC and DCC, Maxofin, Superflex, and others.