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General comment ecoQuery: https://ecoquery.ecoinvent.org/3.10/cutoff/dataset/21424/documentation
This dataset describes the operation of a typical oil refinery in the given geography. Since refineries are very complex the actual unit process modeling is done in a separate refinery model by ifeu and this is a subdivided product-specific dataset.;The ifeu refinery model reproduces the complexity of petroleum refinery plants in which the combination and sequence of processes are usually very specific to the characteristics of the raw materials (i.e. the close relation between the composition of the crude oil and the products to be produced). Refineries differ not only in their configurations, process integration, feedstocks, product mixes, unit sizes, designs, and control systems but also the market situations, locations and ages of the refinery or environmental regulations can result in a wide variety of refinery concepts. It represents the current European state-of-the-art. The basic setting of the model reflects the technical characteristics of European refineries as described in the BREF - BAT reference document for the Refining of Mineral Oil and Gas. Further specific data was collected from companies and production plants and was incorporated in order to elaborate a comprehensive and robust model of a refinery.;The BREF contains not only aggregated numbers or weighted averages of emission and energy or water consumptions, but also encompasses primary data of the majority of refineries in Europe in anonymous form. The data quality is excellent. This data source has been complemented by various specific confidential refinery datasets, by values from Eurostat (e.g. in the case of the energy source mix or process energy), and by literature data. In the case of the BREF, a range of values were mentioned as process parameters for which the arithmetic averages were applied. After adapting the model to the up-to-date mass and energy flows within the European refineries, it has been validated and calibrated by comparing the results to the dataset of the BREF, the Eurostat and the European Pollutant Release and Transfer Register (E-PRTR).;Despite the default settings (weighted EU average), the refinery model was adjusted to fit typical refinery production data in the special geographies. In order to do this data from the refineries in the countries was analysed and an assessment of the refinery complexity (according to the BREF classes) was done. Furthermore crude oil qualities were researched an adjusted (e.g. sulphur content and API class) to fit the specified geography.;Documentation for this model can be found in the ecoinvent refinery report by Fehrenbach et al. (2018).
Activity starts with crude oil entering the petroleum refinery. Waste water treatment, fresh water supply (from nature), refinery infrastructure, crude oil and product storage on refinery grounds and energy provision is included.
Activity ends with refinery products leaving the petroleum refinery.
Mineral oil refineries are highly integrated multi-output production plants where nearly each process step creates a few co-products. ;Unlike many other refinery models, which tend to consider a refinery as a black-box, here a step by step calculation of the complex network of refinery processes was done and gives an integrated sum of all connected processes. The allocation is executed within each of these steps allowing the implementation of the allocation rules at process step level separately and globally, over the system of all steps.;The allocation approach implemented within the ifeu refinery model is designed to consider the complexity of the production system, the valuation of the products (upgrading/downgrading of feedstock material during a specific process), real physical mass flows. The combined allocation procedure is stated by the following sequence of four rules:;1. the general allocation rule refers to the energy content (Rationale: the majority of refinery products are used for energy purposes.);2. The expenditures for the first step of separation (atmospheric distillation) are allocated to all co-products, including the atmospheric residue (Rationale: all co-products from atmospheric distillation will end up in marketable final products.);3. The expenditures for any subsequent process step intended to reduce the quantity of non-intended products (i.e. vacuum distillation and cracking) are allocated to all co-products except for the non-intended products (residues). (Rationale: all these downstream processes within the refinery are intended to reduce non-intended products in favour to increase the yield of non-residual co-products; hence, the expenditures are only allocated to the yielded products.);4. Retention of feedstock: The 3rd rule refers to the allocation of the respective process expenditures; it does not include the allocation of feedstocks. The input material (feedstock) into a refinery process step is always allocated according to the 1st rule: e.g. visbreaker residue takes 40 % energy content of the totalized co-product output of a visbreaker cracker output therefore 40 % of the visbreaker input (vacuum distillate) and its upstream burden is allocated to the visbreaker residue . (Rationale: Although the downstream processing steps are not intended to produce residues only to reduce them, the residual final products derived from residues (e.g. heavy fuel oil, petroleum coke) are defined as refinery products and not as wastes; if the 3rd rule would apply also for the allocation of feedstock, all final products from non-intended products (residues) would finally achieve LCIs with zero expenditures and emission; de facto they would be treated the same way as waste.) ;The combined allocation procedure involves following consequences:;• The LCI of every refinery product encloses at least 1 MJ crude oil per MJ product feedstock; considering that some refinery products have lower LHVs than crude oil (e.g. petroleum coke or heavy fuel oil), such refinery products enclose less than 1 kg crude oil per kg product;;• Final products with relevant shares derived from sequential processing accumulate higher loads than products predominantly derived from straight-run;;• An exception is the heavy products derived from non-intended products, even if they pass a cascade of cracking processes; without rule 3 and 4 heavy fuel oil would turn out to be the product with the highest burden, which would contradict any value-based perception of the refining business. |
