Tar Sand Hydrogen Production Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing process for producing sweet crude from tar sand oil is sensitive to process failures, particularly in hydrogen availability due to the low reliability of gasification and de-asphalting units.
Innovation Solution
A process that involves atmospheric distillation of tar sand feed, hydrocracking with hydrogen, partial oxidation of the asphalt fraction in a gasification reactor, water gas shift reaction, and purification of hydrogen, with additional capacity in parallel-operated gasification reactors and a spare reactor for methane partial oxidation to ensure hydrogen availability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If gasification units and de-asphalting units are used to produce hydrogen for hydroprocessing, then hydrogen can be obtained from tar sand feed, but the reliability of hydrogen availability is low due to process failures
Solution Approach 1:
The patent applies preliminary action by separating the asphalt fraction before gasification to prepare a more suitable feedstock for the gasification unit. This pre-processing step ensures that when gasification occurs, the feed is already optimized, reducing the risk of process failures and improving hydrogen availability reliability.
Solution Approach 2:
The patent changes the physical state parameter of the asphalt fraction by heating it to a liquid state before feeding to the gasification unit. This parameter change ensures proper flow and combustion characteristics in the gasifier, improving operational reliability and preventing process failures that would otherwise reduce hydrogen availability.
2Quantity of substance
If asphalt fraction is fed to gasification reactor, then hydrogen and carbon monoxide are produced, but burner damage may occur without proper feed preparation
Solution Approach 1:
The patent applies preliminary action by separating the asphalt fraction from vacuum bottoms before gasification. This pre-separation removes impurities and prepares a more suitable feedstock, preventing burner damage while maintaining hydrogen production quantity.
Solution Approach 2:
The patent changes the temperature parameter of the asphalt fraction, heating it to a liquid state before feeding to the burner. This parameter change ensures proper atomization and combustion, preventing burner damage from improper feed conditions while maintaining hydrogen production levels.
3Reliability
If de-asphalting unit is used to separate asphalt fraction, then feed for gasification is obtained, but the unit lacks high reliability to ensure continuous operation
Solution Approach 1:
The patent applies universality by designing the system so that vacuum bottoms can serve dual purposes: normally being processed through de-asphalting to obtain asphalt fraction, but alternatively being fed directly to gasification when de-asphalting fails. This multi-functionality ensures continuous operation despite de-asphalting unit reliability issues.
Solution Approach 2:
The patent applies beforehand cushioning by preparing alternative feed pathways in advance. When de-asphalting unit failures occur, the system can immediately switch to using vacuum bottoms as gasification feed, cushioning against process disruptions and ensuring continuous hydrogen production.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the reliability of hydrogen production by allowing quick adaptation to feed changes and reduces hydrogen availability loss in case of reactor failure, while preventing burner damage through a multi-orifice burner design with a moderator gas.
Implementation Method 1
supplying an atmospheric distillation bottoms of a tar sands originated feed to a vacuum distillation to obtain a vacuum gas oil and a vacuum bottoms
Implementation Method 2
contacting the vacuum gas oil with hydrogen in the presence of a suitable hydrocracking catalyst to obtain a sweet synthetic crude
Implementation Method 3
feeding said asphalt fraction to a burner of a gasification reactor where the asphalt fraction is partially oxidized in the presence of an oxidizer gas in a burner to obtain a mixture of hydrogen and carbon monoxide
Implementation Method 4
performing a water gas shift reaction on the mixture of hydrogen and carbon monoxide
Implementation Method 5
separating hydrogen sulphide and carbon dioxide from the shifted gas in an acid removal unit thereby obtaining crude hydrogen
Data Source
AI summary
A process to prepare a sweet crude from an ash containing and heavy fraction of a tar sand oil comprising supplying an atmospheric distillation bottoms of a tar sands originated feed to a vacuum distillation to obtain a vacuum gas oil and a vacuum bottoms and contacting the vacuum gas oil with hydrogen to obtain a sweet synthetic crude. The vacuum bottoms obtained are separated into an asphalt fraction comprising between 0.1 and 4 wt % ash and a de-asphalted oil and the asphalt fraction is fed to a burner of a gasification reactor to obtain a mixture of hydrogen and carbon monoxide on which a water gas shift reaction is performed. Hydrogen sulphide and carbon dioxide are separated from the shifted gas in an acid removal unit thereby obtaining crude hydrogen which is purified and used to obtain the sweet synthetic crude. The asphalt fraction is provided to the burner in a liquid state and wherein in case the separation step fails to provide sufficient feed for the gasification reactor, vacuum bottoms from the first step are fed to the burner in a liquid state.