Ichihara Chemical Plant, Chiba, Japan
The Ichihara Works petrochemical plant in Chiba, Japan, has been run by Mitsui Chemicals since it first went into operation in 1967.
The main work of the petrochemical plant in the past has been based around its central ethylene production facility, which supplied feedstock materials to produce polymer resins and derivatives for the world market (612,000tpa of ethylene).
The 1,390,000m² plant produces petrochemicals such as olefins, aromatic hydrocarbons, polyethylene, polypropylene and TBA, along with basic chemicals such as phenol, BPA, acetone, epoxy resin, ethylene oxide, ethylene glycol and aniline.
Changes at Ichihara
With the changing market for chemical feed stocks and products, Mitsui announced in January 2009 that it was changing the face of production at Ichihara Works.
Mitsui reorganised its corporate structure to replace its product portfolio which competes with Middle East products to a value-added product portfolio employing differentiated technology, and which does not compete with Middle Eastern suppliers.
The first step included termination of the Ichihara EOG (ethylene oxide and ethylene glycol) plant due to large amounts of ethylene glycol being produced in Asia and the Middle East, making the market uncompetitive (used to produce polyester fibre and antifreeze).
Market conditions for domestic ethylene glycol are expected to become extremely dull due to large supplies of EG coming from numerous plants newly established in the Middle East and Asia.
The Ichihara EOG plant was shut down and the 80,000t of ethylene used for EOG production is being diverted to the production of value-added products.
Mitsui constructed a new 1-Hexane plant which uses 40,000tpa of the ethylene surplus to produce 30,000tpa of ethylene trimerisation, using a new 600-fold chromium catalyst. The plant required an investment of 7.5bn yen. It began commercial operation in April 2011.
1-Hexane is used as co-monomer of HAO-LLDPE (high-alpha olefin-linear low-density polyethylene) and HDPE (high-density polyethylene). The global consumption of the chemical is around 650,000tpa, with an expected growth rate of 6% to 7% per annum.
Mitsui in a joint venture with the Idemitsu Kosan Company, called Prime Polymer, which uses 1-Hexane to produce a metallocene linear low-density polyethylene called Evolue using gas-phase polymerisation (for this production 1-Hexane has previously been purchased from external suppliers).
The output of Evolue increased from 240,000tpa to 300,000tpa. Evolue has superior strength, transparency and sealing properties than other linear low density polyethylenes produced with Ziegler-Natta catalysts.
Mitsui now produces specialist polyethylene and polypropylene for the markets using its unique patented technology.
In January 2009 Mitsui announced its decision to withdraw from aniline sales and terminate its 66,000tpa production plant at Ichihara.
The decision is due to the increased production of aniline by methane diisocyanate (MDI) related manufacturers resulting in a decline in market demand.
Mitsui Chemicals Polyurethanes' Ohmuta Works at Fukuoka uses aniline produced at its own plant in MDI production.
Only 1% of the phenol produced at the plant is needed for aniline production and the remainder of the phenol production is supported by increased demand for bisphenol.