Dual-Stripper Hydroprocessing Recovery Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydroprocessing recovery units are energy-intensive due to high temperature and pressure requirements, and existing designs inefficiencies lead to duplicative heating needs, increasing energy consumption and costs.
Innovation Solution
Implementing a dual-stripper system where a cold stripper processes a relatively cold hydroprocessing effluent stream and a hot stripper processes a relatively hot effluent stream, allowing for separate heating and direct feed to the fractionation column, reducing the need for a fired heater and decreasing energy usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single stripper is used to process all hydroprocessing effluent streams, then the equipment complexity is reduced, but energy consumption increases due to duplicative heating requirements
Solution Approach 1:
The effluent stream is divided into two separate streams based on temperature: a hot effluent stream and a cold effluent stream. Each stream is processed by a dedicated stripper (hot stripper and cold stripper respectively), preventing mixing and duplicative heating. The hot stripper processes only the hot stream while the cold stripper processes only the cold stream, eliminating energy waste.
Solution Approach 2:
The harmful thermal mixing effect is extracted and eliminated by separating the processing paths. The hot effluent stream is extracted and processed separately in the hot stripper, while the cold effluent stream is extracted and processed separately in the cold stripper, preventing the energy-wasting mixing that would occur in a single stripper system.
2Device complexity
If hot and cold effluent streams are mixed in a single stripper, then the device complexity is reduced, but heating duty increases due to redundant heating requirements
Solution Approach 1:
The heating function is segmented and assigned to separate strippers based on the temperature characteristics of the effluent streams. The hot stripper is designed to handle hot effluent with appropriate heating requirements, while the cold stripper handles cold effluent with different heating requirements, eliminating redundant heating duty.
Solution Approach 2:
Each stripper is optimized for its specific stream temperature characteristics. The hot stripper is configured with heating and stripping conditions appropriate for hot effluent, while the cold stripper is configured with conditions appropriate for cold effluent, ensuring efficient local processing without imposing unnecessary heating requirements on either stream.
3Loss of energy
If separate hot and cold strippers are implemented, then energy efficiency improves by eliminating duplicative heating, but the device complexity increases
Solution Approach 1:
Each stripper serves its designated effluent stream independently, with the hot stripper self-servicing the hot stream and the cold stripper self-servicing the cold stream. This eliminates the need for complex interconnections and control systems that would be required to manage a single stripper handling both temperature streams, making the increased complexity manageable through functional independence.
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 reduces the fuel used in the product fractionation heater by approximately 40% and decreases capital equipment costs, resulting in lower operational and capital expenses for hydroprocessing units.
Implementation Method 1
A relatively cold hydroprocessing effluent stream which is a portion of the hydroprocessing effluent stream is stripped in a cold stripper to provide a cold stripped stream
Implementation Method 2
A relatively hot hydroprocessing effluent stream which is a portion of the hydroprocessing effluent stream is stripped in a hot stripper to provide a hot stripped stream
Implementation Method 3
The relatively cold hydroprocessing effluent stream and the relatively hot hydroprocessing effluent stream are fractionated in a product fractionation column to provide product streams
Data Source
AI summary
A process is disclosed for recovering hydroprocessing effluent from a hydroprocessing unit utilizing a hot stripper and a cold stripper. Only the hot hydroprocessing effluent is heated in a fired heater prior to product fractionation, resulting in substantial operating and capital savings.