Chemicals from Acetylene: Back to the Future?
Tuesday June 26, 10:43 am ET
Nexant Sees Significant Prospects for Reviving Older Technology
WHITE PLAINS, N.Y.--(BUSINESS WIRE)--Between 1960 and 1970, when worldwide acetylene production peaked, it served as the primary feedstock for a wide variety of commodity and specialty chemicals. Advances in olefins technology, concerns about acetylene safety, but mostly loss of cost competitiveness, reduced and effectively limited the importance of acetylene. Now, with the current rise in petroleum prices, acetylene is finding a new place in the chemical industry. In a newly released ChemSystems® Special Report -- Chemicals from Acetylene: Back to the Future? -- Nexant experts analyze the technologies and economics of producing acetylene and commercially proven and technically attractive acetylene derivatives.
Conventional steam cracker feedstocks, whether derived from crude oil or from refinery products, have continued to increase in cost as compared with coal and remote natural gas -- coal and natural gas being the feedstocks for acetylene production.
Given the proven competitiveness of vinyl chloride from coal in China, the report re-examines other important acetylene derivatives for large-scale production. The report indicates that regions with low-cost coal and natural gas can now consider acetylene as a chemical feedstock and re-evaluate the known and potential derivative chemicals that can be produced from acetylene. It then examines major topics such as the process routes for acetylene and acetylene derivatives production; regional cost-of-production economics; and the potential for exporting derivatives from low-cost coal and natural gas regions.
The competitive use of acetylene as a feedstock for vinyl chloride monomer (VCM) production in China suggests that acetylene chemistry may be a competitive route for producing other chemical derivatives under the right circumstances. Acetylene production technology is mature and proven, and has experienced significant improvements in conventional processes, especially coal to calcium carbide to acetylene. The availability of low-cost natural gas or coal, and the low rise in coal prices as compared to crude oil prices, makes acetylene technology a viable possibility in many applications and regions.
Most acetylene-based chemicals used in the world today are based on inexpensive coal feed. Natural gas-based acetylene production is far rarer and occurs on a much smaller scale. The continued growth of acetylene technology will depend largely on the future cost of coal and natural gas, and the ability to produce large-volume commodity chemicals not produced today. The production of commodity chemicals, such as ethylene and benzene, is technically feasible, but a sound economic advantage will have to be proven to warrant commercialization.
The report discusses the uncompetitive cost position of a typical U.S. location for the three primary acetylene production processes: calcium carbide from coal, partial oxidation (POX), and plasma arc from natural gas, when all three are normalized at a 215,000 ton per year capacity, sufficient for a large-scale VCM plant. This cost comparison takes into account the number of lines needed for each technology based on current single-line capability.
The calcium carbide-based acetylene plant is by far the lowest cost producer. Coal in the U.S. is priced at $35 per short ton, a very inexpensive carbon source compared to natural gas, priced at $6.63 per MMBtu. Although the carbide, POX, and plasma arc processes feature relatively high power consumption per unit product, the plasma arc is exceptionally high -- a significant disadvantage given the U.S. power cost of 6.31 cents per kWh.
Producing VCM from acetylene in China is not only competitive, but an economic reality. Alternatively, acetylene-based acrylonitrile production would also be competitive in China. Nexant evaluated other chemicals in this manner, including acrylic acid, BDO/THF, isoprene, chloroprene, and vinyl acetate -- comparing production in the U.S., China, and a hypothetical Eastern Europe/Eurasia location.
The potential production of large volume commodity chemicals from acetylene, namely ethylene and benzene, is also evaluated. Nexant analyzes promising patents and estimates cost of production economics for use in comparison to conventional process and feedstock economics.
Though not directly cost competitive, the process route does exhibit low enough costs to have promise in the export market for ethylene produced in Eastern Europe, the Middle East, and China and exported to the U.S. in 2010.
Nexant's products and services help clients solve critical strategic and operational challenges in several key areas: chemicals and petrochemicals; oil and gas; electric power; energy technology; energy management; retail and wholesale power markets; and enterprise risk management. The company is headquartered in San Francisco, CA. Nexant maintains offices in London, U.K.; Bangkok, Thailand; Beijing, China; Tokyo, Japan; Seoul, South Korea; White Plains, NY; Washington, D.C.; Houston, TX; Madison, WI; Salt Lake City, UT; Boulder, CO; Phoenix, AZ; and Los Angeles, CA. The company is owned by a select group of investors and Nexant management and employees. Nexant® and ChemSystems® are proprietary trademarks of Nexant, Inc.
Source: Nexant, Inc.
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