Cradle to Gate
Identity ID
fb257fe9-c5f1-439f-abca-5c1d66f3a08f
Materials
Associated ID
2c449ca5-8d68-4110-afbe-c9e91bc4563a
Included activities starts
Included activities ends
Description
Methane-rich fuel gas is mainly used for combustion and heat supply in cracking furnaces or utility boilers, and can also be used as a supplementary fuel for the park gas system to replace part of the externally purchased fossil fuels; 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
Methane-rich fuel gas is a combustible gas product produced by the separation system of a steam cracking unit. Its main component is methane and contains a small amount of hydrogen, ethane and inert gases. It has a high gas-phase calorific value and good combustion stability. This material is a colorless gas at normal temperature and is suitable for transportation and utilization as a fuel medium in pipeline networks. Methane-rich fuel gas is mainly used for combustion and heating in cracking furnaces or utility boilers, and can also be used as supplementary fuel for the park's gas system to replace part of the purchased fossil fuels.
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.