The Global Ozone Monitoring Experiment-2 (GOME-2) instrument continues the long-term monitoring of atmospheric trace gas constituents started with GOME / ERS-2 and SCIAMACHY / Envisat. Currently, there are three GOME-2 instruments operating on board EUMETSAT's Meteorological Operational satellites MetOp-A, -B and -C, launched in October 2006, September 2012, and November 2018, respectively. GOME-2 can measure a range of atmospheric trace constituents, with the emphasis on global ozone distributions. Furthermore, cloud properties and intensities of ultraviolet radiation are retrieved. These data are crucial for monitoring the atmospheric composition and the detection of pollutants. DLR generates operational GOME-2 / MetOp level 2 products in the framework of EUMETSAT's Satellite Application Facility on Atmospheric Chemistry Monitoring (AC-SAF). GOME-2 near-real-time products are available already two hours after sensing.
The operational H2O total column products are generated using the algorithm GDP (GOME Data Processor) version 4.x integrated into the UPAS (Universal Processor for UV/VIS Atmospheric Spectrometers) processor for generating level 2 trace gas and cloud products.
The total H2O column is retrieved from GOME solar backscattered measurements in the red wavelength region (614-683.2 nm), using the Differential Optical Absorption Spectroscopy (DOAS) method. For more details please refer to relevant peer-review papers listed on the GOME and GOME-2 documentation pages: https://atmos.eoc.dlr.de/app/docs/
technologyComment of kaolin production (RER, RoW):
There exist two different processes for the production of market kaolin - a dry and a wet process. The first one - the dry process - is relatively simple but yields therefore also a lower quality product, reflecting the quality found in the crude kaolin.
The wet process on the other hand side is used to produce filler and coating grades. It is this process that is modeled in this dataset.
The most important four steps of the wet process are the following:
- Mining: Nowadays most of kaolin mining is done in open pit mining. Depending on the composi-tion, either mining with shovels, draglines, motorized scrapers and front-end loaders is done (e.g. Georgia, USA) or mining with high-pressure hydraulic monitors (e.g. Cornwall, UK) is done. In the second case, a stream of water is washing out the fine particle kaolin and is leaving the coarse quartz and mica residues within the soil.
- Mineral separation (degritting): Kaolin beeing a mineral, it is obvious that there are always also other minerals (the grit) in the kaolin deposits, which have to be separated. To separate two miner-als, either physical or chemical differences between the two substances are taken as base. In gen-eral, the mined kaolin is mixed therefore with water and a dispersing chemical to form a slurry that is then degritted (by e.g. rake classifiers, hydrocyclones or screens).
- Kaolin benefication: When the separated kaolin fullfills not the specification asked a benefication process is added to improve e.g. the brightness (either by magnetic separation or by bleaching with ozone or hydrogen peroxide), the rheology (by blending different kaolins), the purity (either by blending or by magnetic separation) or the grain size distribution (again blending as a possibility). In this step, the producer is also deciding the form of delivery (bulk, powder, slurry).
- Storage & transport: The storage is done either in silos (bulk and powder) or in tanks (slurries). Due to the fact that customers more and more apply for the 'just in time' principle, the storage ca-pacities of the producers are increasing and the transports are done more and more by lorry to the customer (more flexible than other means of transport).
References:
Hischier R. (2007) Life Cycle Inventories of Packagings & Graphical Papers. ecoinvent report No. 11. Swiss Centre for Life Cycle Inventories, Dübendorf, 2007.