Parallel Liquefied Gas Pumps for Pressure-Split Air Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional air separation units with redundant pump configurations face challenges in reducing equipment costs and energy losses due to overpressure and heat penetration, leading to increased costs and reduced thermal efficiency.
Innovation Solution
A liquefied gas supply system with two pumps operating in parallel, one for low-pressure and one for high-pressure purposes, controlled by a unit that adjusts flow rates and valve openings to minimize energy loss and optimize pressure usage, allowing for continuous operation even with pump faults.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a single pump serves as both process pump and product pump, then equipment cost is reduced, but overpressure occurs causing heat penetration and loss of cold heat
Solution Approach 1:
The patent divides the single pump function into two separate pumps: a process pump for circulating refrigerant through the heat exchanger and a product pump for delivering product gas. This segmentation allows each pump to operate at its optimal pressure without causing overpressure and heat penetration, thereby reducing cold heat loss while maintaining cost-effectiveness through specialized function allocation.
Solution Approach 2:
The product pump is designed with multi-functionality to serve both as a product delivery pump and as a backup for the process pump. When the process pump fails, the product pump can assume the process pump's function, ensuring continuous operation without requiring a dedicated backup pump for each function, thus balancing reliability with cost efficiency.
2Reliability
If redundant pump configuration is provided, then operational reliability is improved, but equipment cost and construction cost increase
Solution Approach 1:
The product pump is designed with multi-functionality to serve both as a product delivery pump and as a backup for the process pump. When the process pump fails, the product pump can assume the process pump's function, ensuring continuous operation without requiring a dedicated backup pump for each function, thus balancing reliability with cost efficiency.
3Stress or pressure
If pump operates at design point based on maximum pressure and flow rate, then high-pressure demand is met, but energy loss increases when demand falls below lower limit of pump throughput
Solution Approach 1:
The patent implements dynamic operation where the process pump and product pump can adjust their flow rates and operating points based on real-time demand. The control system monitors process requirements and adjusts pump operations to maintain optimal efficiency, preventing energy loss that would occur if pumps operated continuously at maximum design capacity regardless of actual demand levels.
Solution Approach 2:
The system changes operating parameters (pressure, flow rate) dynamically based on demand. When high-pressure demand is required, the product pump operates at higher capacity; when demand decreases, the pump operates at lower capacity or is shut down, avoiding the energy loss associated with operating below the pump's efficient throughput range.
4Stress or pressure
If overpressure occurs in reflux liquid, then pump can meet product pressure requirements, but heat penetration increases leading to loss of cold heat
Solution Approach 1:
The patent divides the single pump function into two separate pumps: a process pump for circulating refrigerant through the heat exchanger and a product pump for delivering product gas. This segmentation allows each pump to operate at its optimal pressure without causing overpressure and heat penetration, thereby reducing cold heat loss while maintaining cost-effectiveness through specialized function allocation.
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 configuration reduces power consumption, minimizes energy loss, and enhances thermal efficiency by optimizing pump operation and pressure management, thereby reducing construction and operational costs.
Implementation Method 1
a first liquid feed pump (11) that is configured to feed a first liquefied gas from a supply source (e.g., a column bottom portion of a rectification column, or a product liquefied gas storage tank, etc.) to a low-pressure supply destination (e.g., a rectification column, vaporizer, or condenser, etc.) for low-pressure purposes
Implementation Method 2
a second liquid feed pump (12) that is configured to feed a second liquefied gas from the supply source to a high-pressure supply destination (e.g., a heat exchanger or demand destination, etc.) for high-pressure purposes
Implementation Method 3
means for sending feed air to the heat exchanger to be cooled and from the heat exchanger to the first rectification column
Implementation Method 4
a top condenser enclosed within a condenser section having an operating pressure which is the second pressure
Data Source
AI summary
An air separation unit comprises a first rectification column, having a top condenser and a second rectification column placed side by side, a heat exchanger, a first pump and a second pump connected in parallel, the first pump being capable of producing liquid at a first liquid pressure and the second pump being capable of producing liquid at a second liquid pressure, higher than the first pressure, each pump having an inlet connected to the second column, a first outlet of the first pump being connected to a first outlet conduit, a second outlet of the second pump being connected to a second outlet conduit, the first and second outlet conduits being connected to the condenser section