Technical Info, and Advise for Operators

This page will be expanded and updated continuously.

Atmospheric air contains 78% nitrogen, 21% oxygen, and 1% other gases.
Oxygen is a “fast” gas and is selectively diffused (permeated) through the membrane wall while nitrogen is allowed to travel along the inside of the fiber, thus creating a nitrogen rich product stream.
The oxygen enriched gas, or permeate, is vented from the membrane separator at atmospheric pressure, while the nitrogen is piped from the outlet for further pressure and flow controll.

Membrane_flow

The Oxygen content in the produced nitrogen, is mainly a factor of feed-air pressure and nitrogen flow. But temperature also have some influence.

-Increasing the flow rate will increase oxygen content in the product gas.Higher nitrogen flow, higher oxygen content.
-Decreasing the flow rate will decrease the oxygen content in the product gas.Lower nitrogen flow, lower oxygen content.
-Feed Air pressure increases the productivity of the membranes.

The relationship is illustrated in the following graph:

O2_vs_flow3

This relationship is important to keep in mind when troubleshooting a system that deviate from original spesifications. It could be as easy as adjusting feed-pressure or flow. Knowledge to this could save time and frustration to a system that could need re-tuning.

SHB2883-2
Failure due to ignoring maintenance can be very expensive. Damage to cargo, delayed discharge, reduced discharge rate; Unnecessary COST.

Membranes are the heart of our systems, and they do not require maintenance.
However, there are safety devises and several other components in the system for treating the air, controlling flow, measuring oxygen; and most of these components need some kind of maintenance.

The key-factors are RELIABILITY and COST. Our systems are designed for easy and reliable operation, at all the times. Ignoring maintenance will weaken the reliability-factor, and at one point there will be a failure.

Below you will find memos, technical info etc. that can be of interest to operators of our nitrogen systems.

(PDF) Membrane Disposal