First of all, let's talk about the application of Dankai Teflon film in the photovoltaic field. Teflon PTFE film meets industry standards for UV resistance and weather resistance PV module backsheets. All iron

 

Fluorolon films are all made of PTFE, which has excellent toughness, durability and weather resistance for more than 25 years. The main functions of the solar back panel include water vapor barrier, physical protection

 

Protect wiring and other sensitive components, electrical insulation properties and reduce the operating temperature of the battery. The most popular backsheets are a three-layer "sandwich" film and a two-layer Teflon film.

between the polyester film.

 

Second, Teflon properties

 

The industry prefers to use Teflon as a negative material because of its unique properties that provide excellent long-term protection under various conditions:

 

1. UV protection;

 

2. Moisture-proof;

 

3. Weather resistance;

 

(4) mechanical behavior;

 

5, strength and durability;

 

6. Electrical insulation;

 

7. UL certification;

 

8, inert to a large number of chemicals, solvents and stains.

 

For many years, Teflon has been used as an important component of negatives. Tests show that it is still intact and continues to protect the solar modules, which are already in real life.

Live exposed for more than 25 years.

 

 

Figure 1: PTFE film source: network

 

Brief Introduction of 1. Production Teflon Film Calender

 

In the 1930 s, due to the large production of PTFE, the United States and Germany all tried to process rubber calenders to calender PTFE, but in view of these calender rubber machines

 

Limited by the original design, in some aspects can not fully meet the processing requirements of plastics, for example, in order to obtain a more accurate thickness tolerance of PTFE film, in addition to the requirements of pressure

 

In addition to the higher precision of the rolling roller, there is also a set of rolling rubber for accurate film. In addition to the higher precision of the rolling roller, there is also a set of rolling rubber

 

Roller heating system with much higher temperature and easy control, as well as means to compensate for the effect of the roller separation force. So later on the design of a special calendering plastic calender. Calendering

 

The equipment includes calenders and other auxiliary equipment such as extruders and winding devices.

 

Calenders are usually classified by the number of rolls and the arrangement. Depending on the number of rollers, the calender has two-roll, three-roll, four-roll, five-roll or even six-roll, as well as three-roll or four-roll

 

The calender is used the most. In order to avoid the adverse effects of the transverse pressure of adjacent calendering rollers on the thickness of PTFE film, the original straight calender was gradually changed to L-type and inverted L-type.

 

After 1950, the United States and West Germany have designed Z-type and oblique Z-type four-roll calender. The two-roll calender is mainly vertical, and this roller arrangement makes the equipment structure.

 

Simple, easy to manufacture, low production and manufacturing costs, small footprint, light weight, motor power utilization is more economical.

 

At present, China's equipment in the plastics, rubber, paper and other industries is relatively backward, especially the rolling equipment. Most of them are not configured for automatic thickness measurement and thickness measurement of processed products

 

Automatic control system, such as two-roll calender this relatively small equipment is so, mainly using manual thickness measurement, manual pitch, which not only affects the quality of the product, but also

Waste of processing raw materials.

 

 

Figure 2: PTFE film source: network

 

2. comparison of traditional filter media, the superiority of PTFE membrane filter media

 

The traditional bag filter uses bag filter material to filter the dust-containing gas, so that the dust is trapped on the filter material, and the dust layer is formed to continue to collect dust particles to achieve the dust removal effect. in the pocket

 

When the dust collector starts to be used, it mainly relies on the effects of screening, interception, inertial collision, diffusion and static electricity generated by the filter fiber to retain the dust on the surface layer of the filter material. woven fabric

 

Filter materials (such as 729,208, etc.) retain dust particles on the surface of the filter material. Non-woven filter materials (non-woven fabrics, needle felt, etc.) can not only adhere to the surface of the filter bag, but also enable dust particles to enter

 

Inside the filter material, there is an internal filtering effect. The above effects make the dust particles accumulate on the surface of the filter material, forming a "dust layer". The deep filtration of traditional filter material mainly depends on one time

 

The role of the dust layer, in order to ensure the continuous work of the filter material, the filter material should be cleared regularly, and the "one-time dust layer" should not be damaged as far as possible ". During the filtration process, one

 

The secondary dust layer is only relatively efficient for a period of time, and the efficiency of deep filtration for trapping fine particles is very low.

 

PTFE membrane filter material is the use of a layer of microporous foamed PTFE film coated on the surface of the general traditional filter media. PTFE membrane filter material in addition to the traditional filter material dust removal mechanism

 

In addition to the five effects of screening, interception, inertial collision, diffusion and static electricity, due to the many micropores and small pore size of the membrane, only 0.3μm ~ 0.5 μm, it is difficult for dust particles to pass through the micropores.

 

Holes, so the sieving effect of the film removes dust particles above 0.3μm, and the interception and inertial collision effect of the film on dust are very high for dust particles above 0.1μm.

 

removal efficiency. The sieving effect of membrane micropores on dust plays a leading role in the five effects. PTFE membrane filter material uses surface filtration instead of using "a dust layer"

 

Filter, PTFE film from the role of a dust layer, the bottom cloth material only from the role of supporting the skeleton. The filter material is very efficient from the beginning, and does not need a dust layer to improve efficiency

Rate.

 

The traditional filter material relies on inertial collision and interception to form a dust layer, and relies on the screening effect of a dust layer to filter, so the traditional filter material needs to have a more stable one.

 

The dust layer can achieve the ideal dust removal effect, but it is difficult to do in actual operation. The dust layer is in a repeated state of formation → stabilization → ash removal destruction → formation.

 

The surface of Dankai PTFE film is extremely smooth and the friction coefficient is small. It is difficult to form a thick dust layer on the surface of the film. Tests have proved that even if the number of times of cleaning is small, the dust on the surface of the film accumulates.

 

Tired is also very little, dust can be stripped naturally. Therefore, the formation and destruction of "a dust layer" has little effect on the dust removal effect. Tetrafluoro membrane filter material mainly uses thin micropores for dust removal

 

The sieving effect of the membrane is the difference between the new type of PTFE membrane filter material and the dust removal mechanism of the traditional filter material.

 

 

Figure 3: PTFE film source: network

 

3. PTFE membrane for oily wastewater treatment

 

Oily wastewater contains a large number of COD, suspended solids, petroleum organic matter, volatile phenol, sulfide and other harmful substances, which is a kind of serious pollution, complex composition, wide range of sources and difficult

Industrial wastewater that is difficult to dissolve and degrade.

 

The methods of treating oily wastewater can be summarized as physical, chemical and biological methods, as well as other emerging water treatment technologies. Due to the complexity of oily wastewater, the use of a single

 

It is difficult to meet the emission standards, so a variety of methods are used to combine treatment technology. Membrane separation, as an emerging treatment technology, is currently used in the treatment of oily wastewater in oil fields.

 

It is microfiltration, ultrafiltration and reverse osmosis, but compared with ultrafiltration and reverse osmosis, microfiltration generally treats nanoscale particles, which have greater flux and anti-pollution ability.

 

oily wastewater is more economical and applicable. The mechanical strength of Dankai PTFE film shows that the influence of the active agent is small, and when the pore size is small enough, it can produce better demulsification effect.

 

The combined process of hydrolysis acidification and PTFE membrane bioreactor is used to treat the oily wastewater from the simulated oilfield in the laboratory.

 

The hollow fiber membrane module provided has a membrane pore size of 0.1-0.2 μm. The experimental results show that the combined process of simulated oily wastewater COD, ammonia nitrogen, petroleum pollutants, volatile

 

The results show that the process can be well applied to the treatment of industrial oily wastewater. The entrapment efficiency of PTFE membrane for contaminants is in

 

10% ~ 98%, and is not affected by immersion organic compound and hydraulic retention time, which plays a positive role in the treatment of oily wastewater. PTFE film was also carried out with polyvinylidene fluoride

 

Ethylene raw water filtration comparison experiment, the experiment found that PTFE flux is larger, oil resistance is better, confirmed the advantages of Dankai PTFE film for oily wastewater treatment.

 

This article is originally created by Teflon's little sister. Welcome to pay attention and take you to grow knowledge together!