Cradle to Gate
Identity ID
3658ace6-6a70-4eca-8240-bddd04ceaeec
Materials
Associated ID
de8bb2a5-b593-449a-bf48-325b1a8a0b9e
Included activities starts
Included activities ends
Description
This dataset represents a life cycle inventory (cradle-to-gate) for Coking clean coal, starting from dense middlings coal beneficiation to the production of cleaned coking coal. It covers all coal washing-related activities, but excludes external conditions beyond the coal preparation plant (such as raw coal mining, utilization of Clean coal), as well as direct or indirect greenhouse gas emissions from personnel commuting and daily office operations during the coal washing process. Based on national standards including the "Cleaner Production Standard for the Coal Mining and Washing Industry" (HJ 446-2008) and the "Emission Standards for Pollutants from the Coal Industry", this dataset was compiled from multiple data sources and is representative of the average production level in Shanxi.
Activity Description
This dataset describes heavy medium coal beneficiation, a method that uses a heavy medium suspension to separate coal from impurities. The specific process is as follows:
Coal crushing:
Raw coal is crushed by a crusher into particles suitable for washing, typically below 50 mm. The crushed coal then enters screening equipment for particle size classification.
Preparation of heavy medium suspension:
Magnetite powder or other heavy medium materials are mixed with water to prepare a heavy medium suspension of a specific density. The density of the suspension is adjusted according to the density difference between coal and impurities.
Coal separation:
The crushed coal enters the heavy medium separator. In the suspension, coal with lower density floats while impurities with higher density sink, enabling separation of coal and impurities. The separated light fraction (coal) and heavy fraction (impurities) are discharged through different outlets.
Recovery of dense medium:
The dense medium suspension after separation is processed through a magnetic separator to recover magnetite powder, which is then recycled. The recovered dense medium materials are returned to the preparation stage.
Dewatering:
The separated coal contains a certain amount of moisture and is treated by dewatering equipment such as dewatering screens and centrifuges to reduce moisture content and increase the calorific value of the coal.
Storage and transportation:
After dewatering, the coal is stored and transported. To prevent coal from moisture absorption and spontaneous combustion during storage and transportation, protective measures should be taken, such as using coal sheds or enclosed stockyards for storage.
Process Description
Coking coal in Shanxi Province is widely distributed in the Taiyuan Formation and the Shanxi Formation. The Taiyuan Formation includes gas coal, fat coal, coking coal, lean coal, and gas-fat coal, while the Shanxi Formation includes gas coal, fat coal, coking coal, and lean coal. For raw coal from the Taiyuan Formation, ash content ranges from 6.95% to 37.97%, volatile matter from 9.6% to 41.01%, maximum thickness of the vitrinite layer from 0 to 40 mm, total sulfur from 0.68% to 5.97%, and the net calorific value on an as-received basis (Qnet,ar) from 7712 to 9078 kcal/kg. For raw coal from the Shanxi Formation, ash content ranges from 16.53% to 34.33%, and volatile matter from 13% to 40%. 0.03%, the maximum thickness of the vitrinite layer ranges from 0 to 75 mm, and the net calorific value on an as-received basis (Qnet,ar) ranges from 7400 to 8660 kcal/kg.
Time period
2022
2026
Geography
China,Shanxi
Geography comment
Forming Shanxi's average data through merging data from multiple sources.
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
Heavy middlings coal beneficiation is an effective coal cleaning method primarily used to improve coal quality. This method employs a liquid medium with a density between that of coal and gangue for separation. The separation media used include heavy liquids and suspensions. Currently, both domestically and internationally, suspensions prepared by mixing magnetite powder with water are widely used as the separation medium in coal beneficiation. Heavy middlings coal beneficiation involves several steps, including coal crushing, preparation of the heavy middlings suspension, coal separation, recovery of the heavy middlings, and dewatering processes.