Cradle to Gate
Identity ID
cd8469e2-b9e9-4571-aac9-2efda1caa3b5
Materials
Associated ID
2c449ca5-8d68-4110-afbe-c9e91bc4563a
Included activities starts
Included activities ends
Description
In industry, hydrogen is mainly used in hydrofining, hydrocracking and desulfurization reactions, and is also used in ammonia synthesis, methanol synthesis and reducing protective atmosphere scenarios; The dataset includes the main raw and auxiliary materials, energy, wastes and atmospheric emissions of the production process, in which the preliminary treatment of wastewater in the utility/auxiliary processes and the waste-gas treatment process are included within the dataset boundary, while infrastructure such as the manufacture of production equipment and plant construction is not included within the dataset boundary; the data inventory is formed by merging data from multiple sources; the production activities of this product include feedstock cracking, separation, waste-heat recovery and other process steps; the dataset contains multiple products, allocated by mass combined with special rules.
Activity Description
The production activities of this product include raw material cracking, separation, waste heat recovery and other processes.
Process Description
The chemical formula of hydrogen is H2 (CAS No. 1333-74-0). It is a colorless and odorless gas with low molecular weight, high diffusion coefficient and high combustion heat value. Its chemical activity is controlled by reaction conditions at normal temperature and pressure. Hydrogen has a wide flammable range in the air, so leakage monitoring and explosion-proof control need to be focused on during use. This product is mainly used in industry for hydrorefining, hydrocracking and desulfurization reactions. It is also used in ammonia synthesis, methanol synthesis and reducing protective atmosphere scenarios.
Time period
2016
2026
Geography
China
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
This dataset models a feedstock mix of naphtha, propane, and liquefied petroleum gas. At 800-900°C in a cracking furnace, longer-chain saturated hydrocarbons are broken down into shorter unsaturated compounds. The main products include ethylene and propylene, with hydrogen, mixed C4 hydrocarbons, and other co-products. Cracking-unit designs are broadly similar and require only minor modifications for local conditions. Naphtha remains the principal feedstock, although the shares of light components such as propane and butane and liquid feedstocks such as liquefied petroleum gas have increased in recent years. A portion of the by-product fuel gas is used in the cracking furnaces.
1. Cracking: Feedstocks entering the plant are preheated, mixed with dilution steam, and heated before cracking in the radiant section of the furnace. Liquid-feed furnaces use highly selective radiant coils for high-severity cracking, while gas-feed furnaces use multi-pass coils. Cracked gas is sent to the downstream separation section. Both liquid- and gas-feed furnaces are bottom-fired.
2. Separation: Heat is recovered from the cracked gas in a waste-heat boiler, after which the gas serves as stripping medium in the gasoline fractionator. The fractionator bottoms leave the plant as crude fuel oil, while the overhead stream is quenched in a quench-water tower and sent to compression. The demethanizer bottoms are sent to the deethanizer, and the deethanizer overhead enters an acetylene converter, where acetylene is selectively hydrogenated to ethylene and ethane.