Pump Seal Pressure Control for Volatile Liquid Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing sealing systems for pumps pressurizing volatile liquids, such as ammonia, face issues with leakage due to changes in pressure and temperature, leading to potential damage to mechanical seals and environmental pollution when the pressure of the barrier gas is lower than the volatile liquid, causing leakage into the atmosphere.
Innovation Solution
A sealing system with a barrier-gas supply system that maintains a constant pressure difference between the barrier chamber and the pump-side seal chamber, incorporating a pressure control valve, relief line with a pressure relief valve, and non-contact seals to prevent leakage and recover volatile fluids, ensuring the barrier gas pressure remains higher than the volatile liquid pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the barrier gas pressure is increased to prevent volatile liquid leakage, then the sealing reliability improves, but the energy consumption and system complexity increase
Solution Approach 1:
The patent employs a pressure detection device that continuously monitors the pressure difference between the barrier gas and volatile liquid, feeding this information to a control device. The control device automatically adjusts the barrier gas supply to maintain the required pressure differential, ensuring sealing reliability without manual intervention or overly complex system design.
Solution Approach 2:
The patent replaces complex mechanical pressure control mechanisms with an electronic control system that uses sensors and automated regulation. This substitution simplifies the overall system while maintaining reliable sealing through precise electronic pressure management.
2Reliability
If the barrier gas pressure is maintained high to prevent leakage, then the sealing performance improves, but the risk of damage from pressure changes increases
Solution Approach 1:
The patent introduces a pressure control device that proactively maintains the pressure difference between barrier gas and volatile liquid before leakage can occur. By continuously regulating pressure in advance, the system prevents the harmful effects of pressure imbalances and potential seal damage.
Solution Approach 2:
The pressure detection device provides real-time feedback on pressure conditions, enabling the control device to make continuous adjustments. This feedback mechanism ensures the pressure difference remains within safe operating parameters, preventing damage while maintaining effective sealing performance.
3Reliability
If the mechanical seal is used to prevent volatile liquid leakage, then the sealing effectiveness improves, but the risk of seal damage from liquid contact increases
Solution Approach 1:
The patent introduces barrier gas as an intermediary substance between the volatile liquid and the mechanical seal. The barrier gas forms a protective layer that prevents direct contact between the volatile liquid and the seal surfaces, thereby maintaining sealing effectiveness while eliminating the harmful effects of liquid contact on the seal.
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
The system effectively prevents volatile liquid leakage into the atmosphere by maintaining higher barrier gas pressure, allowing for recovery of leaked fluids and minimizing damage to mechanical seals, thus ensuring safe handling and environmental protection.
Implementation Method 1
a pressure control valve configured to maintain a constant difference between the pressure in the barrier chamber and the pressure in the pump-side seal chamber
Implementation Method 2
The barrier gas flows into an inner peripheral side of the mechanical seal through a minute gap between the sealing surfaces of the rotating-side seal ring and the stationary-side seal ring
Implementation Method 3
a pressure relief valve attached to the relief line; and a valve actuator configured to open the pressure relief valve when a pressure in the relief line is out of a preset pressure range
Data Source
AI summary
The present invention relates to a sealing system for a pump configured to pressurize a volatile liquid, such as liquid ammonia. The sealing system (2) includes a stuffing box (35) forming a barrier chamber (30) and a pump-side seal chamber (43), a mechanical seal (20) arranged in the barrier chamber (30), and a barrier-gas supply system (32) for supplying a barrier gas into the barrier chamber (30). The barrier gas has a pressure higher than a pressure of the volatile liquid in the pump-side seal chamber (43). The pump-side seal chamber (43) is located between an impeller (7) of the pump (1) and the mechanical seal (20). The barrier-gas supply system (32) includes a pressure control valve (50) configured to maintain a constant difference between pressure in the barrier chamber (30) and pressure in the pump-side seal chamber (43).