58aa0dd1-04b0-6918-96cc-000027963c0fEthylene glycolproduction mix, at plant1,2-ethanediol
glycol
monoethylene glycol
ethane-1,2-diolMaterials productionPlasticsDisclaimer: The LCI and LCIA results of this dataset can vary from the published Eco-profile on PlasticsEurope website due to the conversion of the original LCI to an ILCD compliant LCI, and some updates of characterization factors used in the Eco-profile since the time of the publication. This was done in agreement with PlasticsEurope.0EU27 including NorwayEthylene oxide (EO) is a key chemical intermediate to the manufacture of many products. The production of ethylene oxide started in 1937 with a Union Carbide process based on ethylene and air. In 1958, oxygen (rather than air) processes were introduced by Shell Development Company, and most European EO plants are now based on pure oxygen feedstock.
Ethylene glycols are produced by reacting EO with water. About 40 % of the EO production in Europe is converted into glycols. Globally the figure is even higher by about 70 % (BREF 2003). Therefore EO and ethylene glycols are mostly produced together at integrated plants.
The main product is monoethylene glycol (MEG), but diethylene glycol (DEG) and triethylene glycol (TEG) are also produced. MEG is mainly used for the manufacture of polyester fibres and polyethylene terephthalate (PET), and some as antifreeze in cooling systems. DEG is used in the fibre industry and as tobacco humectant and TEG is used in the manufacture of cellophane for food packaging. DEG and TEG are both used for gas drying.
In practice most EO / EG plants are designed as integrated plants for a production mix of high purity ethylene oxide and glycols. Although there is a number of different EO / EG manufacturing process licensors, the process technologies are broadly similar.
Feedstock ethylene is typically received by pipeline from a steam cracker. The oxygen is regularly provided in pure form by pipeline from an air separation unit. The reaction between ethylene and oxygen is carried out in a multi-tubular fixed bed type reactor with a silver oxide catalyst in the tubes and a coolant on the shell side. The heat generated by the exothermic reactions is removed by the coolant, and is recovered by producing steam. The steam is used as a heating medium in various sections of the plant.LCI resultOtherno extrapolation80.0926 Kt in 2010 (share is estimated with at least 80% of European production)literature values based on European company surveys & European statisticsnoneNo statementexternal review passedMersiowsky I., Dr.-Ing.The goal and scope of this Eco-profile study was confirmed to be a European production average of the following polymer precursors: Ethylene, Propylene, Butadiene, Pyrolysis Gasoline, Ethylene Oxide (EO), and Ethylene Glycols (MEG, DEG, TEG). The geographical scope includes the EU 27 member states and Norway, with a coverage of 50 plants (approx. 92% of European production volume). One important limitation of the technological scope is that the study considered only steam cracking, the most important process to produce ethylene and propylene, whereas the Fluid Catalytic Cracking (FCC) process is not included here. This technological scope is in line with earlier Eco-profiles published by PlasticsEurope which were also limited to steam crackers as a source of olefins and their derivatives. Further, since naphtha is the most common feedstock in Europe, the examined population of cracker units comprised predominantly naphtha crackers (only 2 gas crackers, while most units use a mix of feeds).
The main data source used for this study was a validated confidential report by the petrochemical industry (APPE) under the European Emission Trading Scheme (ETS) on energy use and CO2 emissions of European steamcracking operations. In addition, publicly available literature was used. Other processes, including refinery, ethylene oxidation, and ethylene glycol production, were derived from a proprietary refinery model (developed by the practitioner IFEU through various petrochemical industry projects), and further literature data. The review confirmed that, despite no primary data collection was conducted, the data used are applicable, up-todate, and modelled with a view to internal consistency. The temporal scope was confirmed to be 2009 reference year and valid at least until 2014 in view of the slow technological changes.
The following aspects were subject to particular scrutiny by the review panel:
•The product range of the steam cracker, especially the designation as high value compounds (HVC) for the purposes of allocation;
•the input/output balance of hydrocarbon feedstocks, also accounting for internal loops or further processing of some intermediate products (such as hydrogen and pyrolysis gas);
•specifically, the modelling of non-HVC refinery/fuel gases which are valorised either for thermal energy or for secondary cracking or other post-processing steps – while these will not be burdened with process energy requirements and emissions of the steam cracker itself, they do bear a share of the upstream burdens;
•the use of electric and thermal energy, and the consistent accounting for the associated emissions;
•the consistent and justifiable use of allocation methods;
•plausibility checks of calculations along the productions chains.
A review meeting between the LCA practitioner and the reviewers was held, including a model and database review, and spot checks of data and calculations. The results are thus held to be representative and reliable for the specified production routes. It is noteworthy that, compared with previous studies under the PlasticsEurope Ecoprofiles programme, the results for butadiene and pyrolysis gasoline (pygas) have changed notably:
•According to recent industry data (APPE), the thermal energy (steam) required for the steam cracking process is rather high compared with the previous version of this Eco-profile.
•The previous edition of the Eco-profiles for olefins apparently used a mass allocation for energy demand and emissions of the steam cracking process to all cracker output streams (thus lowering specific burdens), not only to the HVC as in the present version; from today’s perspective, also to ensure consistency with current industry practice (APPE), the latter allocation is deemed more appropriate.
•It is noteworthy that fuel-grade by-products which are returned to the refinery (looped back) were calculated with their calorific value and with their upstream burdens (oil extraction, transport and refining), but no process-related environmental impacts were assigned to them.
•Specifically, the impact indicators for butadiene have increased substantially because butadiene is extracted in a separate facility following the steam cracker, and this additional processing requires thermal energy, electricity, and solvents.
•The impact indicators for pygas (including benzene, toluene and xylene, BTX, and other components) have decreased because of the adjusted allocation.
•The overall levels of greenhouse gas emissions of the steam cracker units were confirmed to be in line with APPE’s ETS reporting and corroborated by bottom-up calculations based on the internal use of low-value byproducts as process fuels (mainly methane). For greenhouse gas emissions, the results of this new version of the Eco-profile are hardly higher than those published in the previous version of 2005.
•Other impact categories changed somewhat in proportion with the process energy requirements. It should be noted, however, that some indicators apparently changed substantially due to life cycle inventory items in the previous version not being specific enough to allow an accurate a posteriori calculation (average characterisation factors applied to unspecified substance flows). In these cases, a comparison with the previous version is strictly speaking not valid.
Further, the review verified that the model and calculations comply with the rules of the PlasticsEurope Ecoprofiles methodology and with ISO 14040–14044: the resulting life cycle inventory datasets for Ethylene, Propylene, Butadiene, Pyrolysis Gasoline, Ethylene Oxide (EO), and Ethylene Glycols (MEG, DEG, TEG) and are thus compatible building blocks for use in other Eco-profile calculations.
Review Summary
The Eco-profile of Ethylene, Propylene, Butadiene, Pyrolysis Gasoline, Ethylene Oxide (EO), and Ethylene Glycols (MEG, DEG, TEG) has been validated to appropriately represent current European production of these polymer precursors. The underlying emission data for the steam cracking process are consistent with reports of the petrochemical industry under the European Emission Trading Scheme (ETS). Other processes, including refinery, ethylene oxidation, and ethylene glycol production, were derived from project and literature data and modelled with a view to internal consistency. The results are thus held to be representative and reliable for the specified production routes.
Reviewer Names and Institutions
Chair: Dr.-Ing. Ivo Mersiowsky – Business Line Manager, Sustainability Leadership, DEKRA Consulting GmbH, Stuttgart, Germany
Co-reviewer: Dr. Martin Patel – Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands
Liebich A.2020-01-01T00:00:00.000ILCD format 1.1Liebich A.2020-01-01T00:00:00.00000.00.001Data set finalised; entirely publishedEco-profiles and Environmental Product Declarations of the European Plastics Manufacturers: EthylenetrueFree of charge for all users and usesGaBi (source code, database including extension modules and single data sets, documentation) remains property of thinkstep AG. thinkstep AG delivers GaBi licenses comprising data storage medium and manual as ordered by the customer. The license guarantees the right of use for one installation of GaBi. Further installations using the same license are not permitted. Additional licenses are only valid if the licensee holds at least one main license. Licenses are not transferable and must only be used within the licensee's organisation. Data sets may be copied for internal use. The number of copies is restricted to the number of licenses of the software system GaBi the licensee owns. The right of use is exclusively valid for the licensee. All rights reserved.Ethylene glycolOutput1.01.00Mixed primary / secondaryUnknown derivationvaluable