Small air separation FAQ - DEAR Air Separation

Causes of reduced efficiency of piston expanders in small air separation unit

The ratio of the actual expansion refrigeration capacity of the expander to the theoretical isentropic expansion refrigeration capacity is the efficiency of the expander. In small air separation unit operation, the efficiency of the expander is generally reduced for the following reasons: poor cooling, the outside world has more heat transfer, pay attention to keep the insulation material dry; inlet and exhaust valves are not closed, exhaust valve seat pressure sleeve top wire is too loose or in...

Sep 23, 2025

Selective adsorption of molecular sieves in small air separation unit

Selective adsorption of molecular sieves in small air separation unit The molecular sieve selectively adsorbs molecules according to their different properties in liquid air separation plant. According to the size of the molecules, the molecules smaller than their pore size are selected for adsorption; for molecules of similar size, according to the polarity of the molecules, the more polar molecules are selected for preferential adsorption; according to the saturation of the molecules, the lar...

Sep 12, 2025

Preventive measures of centrifugal compressor in small air separation unit

Centrifugal compressor, sometimes suddenly produce strong vibration in the production process, gas medium flow and pressure also appear substantial pulsation, and accompanied by periodic dull "call" sound, as well as airflow fluctuations in the network caused by "huffing" "huffing" strong noise, this phenomenon is known as the centrifugal compressor wheezing conditions in small air separation unit. According to the prod...

Sep 04, 2025

Characteristics of centrifugal compressor wheezing phenomenon in small air separation unit

Centrifugal compressor operation once the phenomenon of wheezing, the unit and the operation of the pipe network has the following characteristics. (1) the gas medium outlet pressure and inlet flow rate changes significantly, sometimes may also produce gas backflow phenomenon. The gas medium is discharged from the compressor to the inlet, which is a dangerous working condition. (2) Periodic vibr...

Aug 29, 2025

How do air separation units remove impurities from the air?

Aug 21, 2025

How to check the safety of small air separation unit before pressure testing?

Approved pressure test specifications and instructions or sketches are available at the test site. for multi-pressure stage equipment, all manual and automatic valves are checked to be in the correct open/closed position. all automatic valve operating mechanisms are adequately protected against overpressure. Pressure tests requiring safety nets, safety shields or other restraints at specified safety distances. Each pat...

Aug 13, 2025

VPS gas-liquid separation for small air separation unit

Gas-liquid separation is one of the simplest and most common methods of gas pretreatment. Many process gases in industrial plants, such as steam reforming gas, conversion gas, methanol choke gas, etc., which are based on natural gas, contain only H2, N2, CH4, CO, C02, 02, H20, CH30H or some of these 'light' gases, which H20 orCH3OH, if enter the PSA unit in liquid form, this can cause damage to the performance of the adso...

Aug 05, 2025

Selection of the VPS pre-treatment solution in small air separation unit

The adsorbent can adsorb and desorb small molecules such as H, N2.CH, C0. C02.02 etc. under operating conditions, but it is difficult to desorb liquid, sulphide and many large molecules such as high hydrocarbons (Cs+), tar, naphthalene, benzene etc. after adsorption. These substances are equivalent to 'toxic substances' for the adsorbent, once the adsorbent is adsorbed the adsorbent will not be able to desorb and regenerate in time, or cannot be completely desorbed, the adsorbent will lose its a...

Jul 28, 2025

Flow state and heat transfer coefficient in small air separation unit

Flow state and heat transfer coefficient Fluid mechanics flow experiments tell us that the fluid flow state can be divided into laminar flow, turbulent flow and excessive flow, laminar flow of each flow beam in an orderly flow, will not interfere with other flow beam. In turbulent flow, the bundles are irregularly intertwined and interfere with each other. Excess flow is a state of flow between laminar and turbulent flow. Of these three flow sta...

Jul 18, 2025

Advantages and disadvantages of the accumulator of small air separation unit

The accumulator is a heat exchanger that transfers hot and cold airflow through a filler as a medium. When the cold airflow passes through the accumulator, the cold is stored in the filler and the airflow is heated, and when the hot airflow passes through the accumulator, the airflow takes the cold from the filler. It has the advantage of being simple in structure, low resistance and not easily blocked. The disadvantages are high switching...

Jul 10, 2025

No pressure in the cylinder before starting the air compressor of small air separation unit

According to the starting characteristics of the motor towing the air compressor, when the air compressor is started, its starting current is several times the current in operation. Too much starting current can have a negative impact on the machine itself, the transformer and the transmission line, so we should try to shorten the starting time and the starting current. However, if pressure exists in the cylinder before the ...

Jul 02, 2025

The upper tower pressure of the two-stage distillation tower of small air separation unit

The lower the upper tower pressure, the more conducive to the separation of oxygen and nitrogen, and for the full low pressure air separation unit, the lower tower pressure will also be lowered as the upper tower pressure is reduced, and the lower tower pressure can reduce energy consumption. The pressure at the top of the upper tower depends on the resistance of the nitrogen piping in the heat exchange equipment and the resis...

Jun 24, 2025