S-ANT technology, the production technology of acrylonitrile, has been developed and improved continuously in SINOPEC since 1960. Acrylonitrile is the raw material of synthetic fiber, synthetic resin, synthetic rubber and organic synthesis industry. Acetonitrile and hydrocyanic acid are produced as by-products. So far, more than 90% production process of acrylonitrile is propylene ammoxidation fluidized bed reaction process.