Reverse Osmosis (RO) design in 10 steps

Summary

This video discusses the concept of staging ratios in pressure vessel systems, particularly focusing on the relationship between stages in multi-stage systems. The staging ratio, denoted by 'r', represents the number of vessels in subsequent stages. Examples include systems with four vessels in the first stage and two in the second, with a staging ratio of 2:1. The ideal staging ensures that each stage operates at the same fraction of system recovery. Additionally, the video covers how to calculate the number of pressure vessels in the first stage based on the staging ratio and system recovery.

Takeaways

• 😀 Staging ratio is the relation of the number of pressure vessels between stages in a system.
• 😀 The staging ratio is represented by 'r' and is calculated based on the number of vessels in each stage.
• 😀 A system with four vessels in the first stage and two in the second has a staging ratio of 2:1.
• 😀 A three-stage system with four, three, and two vessels in the first, second, and third stages respectively has a 4:3:2 staging ratio.
• 😀 For brackish water systems, the staging ratio between subsequent stages is usually close to 2:1 for six-element vessels.
• 😀 Shorter vessels in a system tend to have a lower staging ratio than longer vessels.
• 😀 In two-stage sea water systems with six-element vessels, the typical staging ratio is 3:2.
• 😀 The ideal staging ratio ensures each stage operates at the same fraction of the system recovery.
• 😀 The staging ratio is applicable when all pressure vessels in the system contain the same number of elements.
• 😀 The number of pressure vessels in the first stage can be calculated using the staging ratio and system recovery.

Q & A

What is the staging ratio in a pressure vessel system?

The staging ratio refers to the relation of the number of pressure vessels in subsequent stages of a system. It is represented with 'r' and shows the ratio between the number of vessels in different stages.

How is the staging ratio represented for a system with four vessels in the first stage and two vessels in the second stage?

For a system with four vessels in the first stage and two vessels in the second stage, the staging ratio is 2:1.

What is the staging ratio for a three-stage system with four, three, and two vessels in the first, second, and third stages respectively?

The staging ratio for this system is 4:3:2.

What is the typical staging ratio for brackish water systems with six-element vessels?

For brackish water systems with six-element vessels, the typical staging ratio between two subsequent stages is usually close to 2:1.

How does the staging ratio change for shorter vessels in brackish water systems?

The staging ratio for shorter vessels in brackish water systems is typically less than 2:1.

What is the typical staging ratio for two-stage sea water systems with six-element vessels?

For two-stage sea water systems with six-element vessels, the typical staging ratio is 3:2.

What is the ideal staging for a pressure vessel system?

The ideal staging for a system is one where each stage operates at the same fraction of the system recovery, provided that all pressure vessels contain the same number of elements.

How can the staging ratio of a system with multiple stages and a given system recovery be calculated?

The staging ratio of a system with multiple stages and a given system recovery can be calculated using a specific equation that considers the number of pressure vessels in each stage.

How can the number of pressure vessels in the first stage be determined?

The number of pressure vessels in the first stage can be calculated based on the staging ratio of the system.

What is the significance of having the same number of elements in each pressure vessel for system staging?

Having the same number of elements in each pressure vessel ensures uniform operation across stages, which helps maintain consistent system recovery and optimal performance.