Single-Stroke Solvent Pumping for Continuous Chromatography Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solvent delivery systems in chromatography face issues such as flow perturbations, pressure pulses, and band broadening due to refilling events in pumps, leading to noise, reduced throughput, and increased costs, particularly in systems requiring multiple pumps and complex mixing elements.
Innovation Solution
A solvent delivery system utilizing two single plunger pumps with synchronized operational cycles, where one pump refills while the other delivers, ensuring continuous flow without interruptions, and controlled by processors to offset flow rates, reducing the need for fast-moving components and complex mixing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If conventional single stroke pumps are used for solvent delivery, then continuous flow can be achieved, but flow perturbations and pressure pulses occur due to refilling events
Solution Approach 1:
The pump system is segmented into multiple pump heads (first pump head, second pump head, third pump head, fourth pump head) that operate in a coordinated sequence. Each pump head handles a portion of the solvent delivery, allowing one head to refill while others continue delivering solvent, thereby eliminating flow perturbations and pressure pulses that would occur with a single pump head refilling.
Solution Approach 2:
The patent implements continuous solvent delivery by ensuring that at least one pump head is always in the delivery phase while others refill. The coordinated operation of multiple pump heads creates an uninterrupted flow of solvent to the chromatography column, eliminating the interruptions and flow perturbations inherent in single-pump-head refilling operations.
2Duration of action of stationary object
If multiple pumps with multiple pump heads are used to provide continuous flow, then continuous solvent delivery is achieved, but device complexity and cost increase
Solution Approach 1:
The patent combines multiple pump heads into a single integrated pump system that shares common components such as the solvent reservoir, drive mechanism, and control system. This merging approach allows continuous flow delivery while reducing overall system complexity compared to using completely separate pump units, as the pump heads cooperate within a unified structure.
3Loss of time
If conventional pumps with fast-moving plungers are used, then refilling can occur quickly, but system cost and complexity increase due to high-speed components
Solution Approach 1:
The refilling operation is segmented across multiple pump heads occurring at different times. While one pump head refills, others are in the delivery phase, so the refilling action itself can proceed at a moderate, controlled speed without requiring fast-moving components. The segmentation of the refilling process across time and pump heads eliminates the need for high-speed plungers.
Solution Approach 2:
The pump heads are pre-positioned in a sequence where refilling occurs during the delivery phase of other heads. This preliminary coordination ensures that refilling is always occurring in advance or concurrently with delivery phases, eliminating idle time and the need for rapid refilling operations that would require high-speed components.
4Stability of the object's composition
If complex mixing elements are used in solvent delivery systems, then thorough solvent mixing is achieved, but system cost and complexity increase
Solution Approach 1:
The patent combines solvent mixing with the pumping operation itself by having multiple pump heads deliver different solvents in a coordinated sequence. The solvents mix in the delivery line after being pumped, eliminating the need for separate complex mixing elements. This merging of mixing and pumping functions achieves thorough solvent mixing while reducing system complexity.
Solution Approach 2:
The continuous coordinated operation of multiple pump heads delivering solvents in sequence creates a continuous mixing action in the delivery line. This continuous mixing process, driven by the alternating delivery phases of different pump heads, achieves thorough solvent mixing without requiring complex stationary mixing elements that would interrupt or complicate the flow.
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 minimizes flow perturbations and pressure pulses, enhances chromatographic data quality by reducing noise and band broadening, increases throughput, and decreases system complexity and cost by eliminating the need for large, expensive pumps and complex mixers.
Implementation Method 1
The plunger 104 displaces the mobile phase out the outlet 110. The pump 100 pumps the mobile phase from a low-pressure solvent reservoir to a high-pressure environment.
Implementation Method 2
An inlet check valve 108 is provided at the inlet 106 to prevent flow of the mobile phase back out the inlet 106. The outlet check valve 112 prevents flow of the mobile phase back into the single stroke pump 100 via the outlet 110.
Data Source
AI summary
The exemplary embodiments control solvent pumps so that system flow is constant. One or more controllers may control the flow rate produced by the pumps over time. The one or more controllers control a first pump so that, as the first pump is refilling, a second pump maintains a sufficient flow rate to compensate for the lost flow due to the refilling event. In some exemplary embodiments, the one or more controllers control the timing of the refilling event for the first event such that the refilling event overlaps with the equilibrating of the chromatography column with solvent(s) from the second pump. Similarly, the one or more controllers control the timing of the refilling event for the second pump such that the refilling event overlaps with the equilibrating of the chromatography column.