First, the role of molecular sieve in hollow glass

We all know that even if the doors and windows of the past were double-layered, there would be frost in doors and windows in the winter (north). It is produced because the saturated water content in the air becomes water when the temperature changes. The water molecules thus resolved are attached to the inside of the window to form frost. Then, when the hollow glass is put into the molecular sieve and sealed by the glue, the molecular sieve will adsorb the water molecules in the glass sandwich (up to several ppm). In this way, there will be no frost formation. At the same time, due to the reduction of mesons, it can also better play the role of thermal insulation.

Second, the choice of molecular sieve

According to the first part of the description, we know that due to the piece after the hollow glass is sealed by the component glue (butyl, polysulfide). No matter what glue air has a certain amount of penetration, we must choose the molecular sieve with high adsorption value. In other words, molecular sieves can absorb more water molecules even when air is infiltrated. Make it reach a certain dew point. When the molecular sieve adsorption reaches a certain value, the dew point decreases as the air enters a certain value, the hollow glass will dew. This period of time is referred to as the service life of the insulating glass, so when selecting a molecular sieve, it is necessary to select a product with a high adsorption value. However, the molecular sieve adsorption value and the falling powder are contradictory to each other, and the large particle size will also affect the transparency of the insulating glass.

Third, on the detection of molecular sieve

Adsorption heat (heating) Take 25ml water to measure temperature. Take 25g molecular sieve into water to measure temperature. The temperature difference between the two is the temperature rise, the standard is 30 degrees. General warming means that the adsorption value is high.

1, falling powder: Take 5g molecular sieve into 100ml of water, shake evenly, into the turbidity test. The reading number is turbidity. Requires less than 50ppm. If there is no turbidity meter, the molecular sieve can be taken to a certain height to shed sunlight, no dust is better.

Therefore, when selecting a molecular sieve, it is better to see that the powder is small. Then the above mentioned good molecular sieves have a large adsorption value and a small powder fall.

In addition, the hollow glass molecular sieves have 3A and 4A (because the price of 4A is low), and the pore size of the 3A molecular sieve is about 3.2-3.3A. (1A= cm). The 4A aperture is 4.2-4.7A. Among them: The water molecule diameter is 2.8A. Well, 3A and 4A can play a role in adsorbing water molecules. The molecular diameter of nitrogen in the air is 3.6A, so 3A will not adsorb nitrogen; 4A can adsorb nitrogen. Because of the characteristics of the molecular sieve, it adsorbs cold and regenerates under heat. Therefore, when using 4A molecular sieves, the molecular sieve will continue to adsorb the nitrogen in the sandwich when the temperature is lower than the combined temperature after the composite. This results in the formation of negative pressure hollow glass phenomenon; and when the temperature is higher than the temperature of the tablet 4A molecular sieve adsorbed nitrogen will be released, the hollow glass appears convex phenomenon, so that people do not visually Well, while the temperature changes every 24 hours, it means that the insulating glass is changing. This will accelerate the fatigue of the fixed (polysulfide) and closed (butyl) sealants and shorten their service life.

In addition, in order to extend the service life, in addition to selecting a good molecular sieve, it is also necessary to select a good hollow rubber.

Considering the current level of nitrogen production technology and economic considerations, the nitrogen generator uses nitrogen from pressure swing adsorption (PSA). The adsorption material is selected from Japan Takeda high-performance carbon molecular sieve, directly from the compressed air separation preparation purity ≥ 99.99% , (non-oxygen content specified in the national standard) nitrogen. The equipment composition is simple, the equipment covers an area of less, operation, maintenance is simple, and the failure rate is low. And it has low energy consumption and low equipment operating costs.

In order to ensure the long-term, stable and normal operation of the PSA nitrogen-making machine, compressed air must be cleaned, removed, and deoiled prior to entering the nitrogen generator to meet the requirements of the nitrogen-generating machine for compressed air quality. Therefore, we choose domestic famous brands in the selection of cold-drying machines and filters to ensure the stable and long-term operation of the entire system.

Nitrogen in pressure swing adsorption is characterized by a certain relationship between nitrogen flow and purity. The higher the flow rate used, the lower the nitrogen purity. The lower the flow rate used, the higher the nitrogen purity. The user can adjust the flow and purity according to the use conditions.