Initial investments in U.S. olefins production within the petrochemical industry are taking tangible form. Among the latest is ExxonMobil Corp.’s ethane cracker and polyethylene (PE) in Texas.

By processing “affordable supplies of U.S. natural gas,” ExxonMobil said it plans to convert that energy to chemical feedstock.

Typically for the ethylene value chain, the ethane portion of natural gas (ethane is a natural gas liquid) can yield a large amount of ethylene, which can be used as feedstock for PE. Ethylene is a basic olefin, and PE is a polymer and plastic.

The company also noted: “The chemical industry and other industrial sectors account for nearly 30% of U.S. natural gas demand.”

In a June 23 announcement, ExxonMobil Chemical Co. president Steve Pryor stated: “Shale development has provided U.S. chemical producers a double benefit as an energy source and as a key raw material to make plastics and other essential products, creating jobs and economic activity across the value chain.”

ExxonMobil has awarded several construction contracts that took effect immediately, according to its late-June statement.

“Contracts have been awarded to Linde Engineering North America, Inc. and Bechtel Oil, Gas, and Chemicals, Inc. to build olefins recovery units at the ExxonMobil Baytown Olefins Plant. Mitsui Engineering and Shipbuilding Co, Ltd. and Huertey Petrochem S.A. will construct the new olefins furnaces.”

The company further noted: “At the Mont Belvieu Plastics Plant, Mitsubishi Heavy Industries will construct two 650,000 tons-per-year high-performance PE lines. Jacobs Engineering, Ltd. will oversee enabling works and interconnections at both locations. Dashiell Corp. and Wood Group Mustang will provide specialty contracting services.”

Jacobs Engineering Group is among several firms tapped by ExxonMobil to build new facilities, According to an August 12 Jacobs announcement, it secured an engineering, procurement and construction (EPC) contract from ExxonMobil Chemical to provide services for an ethane-cracker project in Baytown, Texas, and downstream facilities in Mont. Belvieu, Texas.

ExxonMobil Chemical Co. is expanding its Mont Belvieu, Texas, polyethylene plant to produce more high-performance premium plastics for export. /Source: ExxonMobil Chemical

The value of the contract was not disclosed, but the award specifies that Jacobs will provide “site enabling works and interconnections services for the two sites. Jacobs’ scope of work includes site preparation of 350 acres for the ethane cracker in Baytown and 100 acres for the product facilities in Mont Belvieu.”

Jacobs said it’s also working to connect the two Texas sites by integrating ExxonMobil’s current facilities with the new 1.5 million-ton-per-year steam cracker in Baytown with the two new PE lines in Mont Belvieu.

The two PE lines will have a combined capacity of 650,000 tons per year. Jacobs said that portion of the project will require about 63,000 feet of pipe to integrate with the current Baytown facility and another 43,000 feet of pipe to integrate with the Mont Belvieu facility.

Commenting on the contract, Jacobs group vice president Mike Autrey said: “Our interface management and integration role is crucial to the success of this expansion project. We are excited to bring our execution skills and experience to support ExxonMobil in this important venture.”

Production of PE products from this site is expected to begin in 2017, according to ExxonMobil.

While ethane and ethylene are comparatively more expensive and difficult to export, PE pellets can be transported easily, then melted and molded into the desired products, such as plastic bags used in grocery stores, milk jugs and plastic bottles, among various other options.

A variety of other olefins and ethylene-specific projects have been announced over the last five years as the U.S. ethylene value-chain benefits directly from the cost-advantage of shale-gas resources.