Gerhard Bauhuis
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The so-called ‘Graphene Flagship’ originitated from the European Commission. This initiative has set a goal to concretise the development of Graphene before the start of 2020, from laboratory level to the consumer market.

What is graphene?

Graphene can be subdivided in three different types: single-layered, double-layered and multi-layered graphene:

  • Single-layered graphene is the purest form available with with unique characteristics. These characteristics make (single-layered) graphene an attractive product for a large number of applications.
  • Double-layered as well as multi-layered graphene have other (less qualitative) characteristics.

As the number of layers increases, it also becomes increasingly cheaper to produce.

In this blog I limit myself to only single-layered graphene, because as of today this type still gives the best result in various research.

Graphene is the world’s first 2D material that consists of only a single atomic layer of carbon; the same material that’s used in diamonds and penciltips. The carbon atoms in graphene are ranked in a hexagon structure. Single-layered graphene is characterized by the following properties

  • 200 times stronger than steel
  • 1.000.000 times thinner than a single human hair
  • The world’s lightest material (1 m² weighs about 0,77 milligram)
  • Flexible
  • Transparent
  • Impenetrable for molecules
  • Excellent electrical and heat conduction

Graphene can also be combined with other materials, such as gases and metals, to produce new materials with the abovementioned properties or to improve existing materials.

Graphene production

At this point there isn’t a method available yet to produce graphene on a larger scale against acceptable costs. However, this is still being researched.

Plasma Enhanced Chemical Vapour Deposition (PE-CVD)

There are a couple of different methods to produce graphene. One of the most common methods in single-layered graphene production is Plasma Enhanced Chemical Vapour Deposition (PE-CVD). In this method, a mixture of gases - in which at least one gas contains carbon – is heated until a plasma has formed. Mass flow meters and controllers are used in CVD processes to dose gases and liquids accurately.

In PE-CVD the plasma forms a graphene layer on a nickel or copper substrate. Heating takes place in a vacuum, but a more ‘green’ CVD process can be used as well, in which heating takes place under atmospheric pressure. By using Chemical Vapour Deposition large sheets of graphene can be produced.

Some of the precursors are liquids that need to be evaporated first, to be used in the CVD process in its gaseous form. It’s very important that the plasma is created with the right proportions and precision. This can be achieved by using highly accurate flow instruments. A deviation in the plasma can cause defects in the graphene layer. Defects can be impurities in the 2D structure that can change the unique properties of the material.

3D-Model structure of graphene

3D-Model structure of graphene

Research for high quality graphene by using atmospheric pressure plasma-based techniques

Our Spanish distributor, Iberfluid Instruments S.A, recently cooperated with the University of Cordoba in a research to investigate the opportunities regarding graphene production on a large scale by using a plasma based technique under atmospheric pressure. In this research ethanol was evaporated with the use of Bronkhorst evaporation system, the so-called Controlled Evaporation and Mixing (CEM) system, to form a plasma. With the use of an evaporation system liquids are being evaporated directly to create the right gas for the plasma. A possible setup of such an evaporation system can consist of a CEM system with an additional liquid flow meter (i.e. a Coriolis mass flow meter, from the mini CORI-FLOW series) for ethanol, a gas flow controller (i.e. an EL-FLOW mass flow controller) for argon, which functions as a carrier gas and finally a temperature-controlled control valve or mixing valve.

An evaporation system like the Bronkhorst CEM system can deliver excellent performance in terms of stability and accuracy. These properties guarantee a reliable creation of plasma, which eventually leads to higher quality graphene.

Bronkhorst CEM system for research at the University of Cordoba

Bronkhorst CEM system for research at the University of Cordoba

In the research document ‘Scalable graphene production from ethanol decomposition by microwave argon plasma torch’ is described why the University of Cordoba (ES) uses the Bronkhorst Controlled Evaporation and Mixing system in the PE-CVD graphene production process.

Areas of application for graphene

Due to a large amount of unique properties research takes place in numerous areas of application. The main focus is on single-layered and double-layered graphene. For now it seems that single-layered graphene still gives the best results. At the same time the use of so-called flakes has been taken into account. These flakes are tiny pieces of graphene which can be mixed with another material, such as polymers. The properties of these materials can be improved by adding graphene flakes, which makes graphene widely applicable in different industries. A couple of examples based on single-layered graphene:

  • Water purification: Scientists are currently developing an advanced filtration system based one graphene oxide that is being used to make polluted water drinkable.
  • Medical industry: Since graphene isn’t poisonous for the human body, research is being done to the possibilities to use graphene in medicine transport in the body, by attaching the medicine to the graphene. Graphene also has the properties to prevent bacteria formation, which makes it ideal to use as a coating for implants.
  • Energy industry: Because of the large surface and excellent electrical conduction, graphene could be used in energy storage. The goal is to make graphene batteries more compact than they are now, while increasing the capacity to make it possible to charge batteries within seconds.
  • Textile industry: Graphene could be used to process electronics in textiles, such as effective, efficient and highly accurate sensors. Furthermore, graphene anti-corrosion coatings and conductive inks can be made.
  • Semiconductor industry: Thanks to good electrical and thermal conductivity, graphene offers possibilities to increase the speed and capacity of chips (for computers and smartphones).

We continue to closely monitor the developments of graphene and we will keep you informed.

Dr. Christian Monse (IPA)
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The emission of nitrous oxides (e.g. NO2) into our atmosphere is a global issue these days. Everywhere researchers and developers are working on better and more accurate simulation and measurement methods, as well as on the development of more efficient catalysts. This applies both to stationary combustion processes (e.g. power plants, steel production and chemical base materials) and to mobile applications in the automotive sector to reduce the NO2 with selective catalytic reduction (SCR). Ammonia or ammonia forming compounds (urea) are added to form pure nitrogen and water.

NOx, a generic term for nitrogen oxides that are most relevant for air pollutions, is a mixture of different nitrogen oxides; nitric oxide (NO) and nitrogen dioxide (NO2). The focus here is on NO2 radicals and its dimer dinitrogen tetroxide N2O4. NO2 is toxic and emissions to the environment should be kept as low as possible. However, NO2 occurs as a by-product in a large number of combustion processes, so that both technical developers in the industry and developers of occupational and preventive medicine have to deal with this substance.

However, this equilibrium also poses the problem of measuring and controlling gas flows containing NO2 in higher concentrations. Especially when using pure NO2, which is in balance with its dimeric form N2O4, which is temperature and pressure dependent and additionally influenced by light and surface conditions (at 27°C only 20% is present as NO2, the remaining 80% as dimer N2O4). The mixture is very sensitive to moisture and can react with humidity to nitric acid (HNO3) and nitrous acid (HNO2), which in turn are highly corrosive.

Gas mixtures with NO2

For investigations of combustion processes with NO2 emission or the testing/ new development of catalysts, a precisely known flow rate of gas mixtures with NO2 must be realised. This applies not only to catalysis but also to the effect of NO2 on the organism and the environment, because NO2 is highly toxic due to its reactivity.

IPA

In one of our projects a system consisting of a gas cylinder, needle valve, backwash unit, transfer lines and mass flow controller should be constructed, which can dose nitrogen dioxide (NO2) in the range between 0- 6 g/h against room pressure.

Challenges with thermal mass flow

Common mass flow meters and mass flow controllers work with thermal measuring principles (with bypass sensor or according the CTA principle (Constant Temperature Anemometry)). Thermal sensors operate on the principle of heat transport in the sensor element. This method depends on the type of gas, since the heat transport depends directly on the heat capacity and the thermal conductivity of the gas to be metered.

Since NO2 has a temperature and pressure-dependent equilibrium with N2O4, the parameters in the sensor element can change constantly. Consideration of the equilibrium using a single conversion factor to a reference gas is not sufficient, especially for pure NO2 or N2O4. Through gravimetric tests, we have determined that massive under-dosing can occur at a dosage of pure NO2 (approx. 10 % of the target value).

A further challenge with a thermal mass flow controller in the closed state, corresponding to a flow rate of 0 ml/min, is that it can produce pseudo signals of up to 10% of the maximum dosing range. The reason for this is that the sensor element contains a mixture of NO2 and N2O4, which is constantly influenced by the active heating of the sensor element. Thus, a heat transport in the device is faked and a flow rate is indicated.

The solution: Use of a Coriolis mass flow controller

The remedy here is a Coriolis mass flow controller instead of a thermal mass flow controller due to its different working principle. It does not matter to what extent the balance of NO2 and N2O4 is on one side or the other, since it is all about the transported mass. When using a Coriolis mass flow controller, however, it must be ensured that the medium to be metered is in a defined physical state, i.e. either in a completely liquid or gaseous state.

Coriolis Mass Flow Meter Mini CORI-FLOW ML120

The boiling point of NO2 at atmospheric pressure is 21 °C, so the complete dosing system, consisting of gas cylinder, needle valve, backwash unit, transfer lines and mass flow controller, can be heated here. Since evaporative cooling occurs inside the mass flow controller when dosing NO2 at the pressure relief point, the temperature there must be set significantly higher than 21 °C. Only at a temperature of at least 45 °C is it ensured that the dosing functions in the range between 0-6 g/h without fluctuations due to condensing and re-evaporating NO2. In this setup a Bronkhorst mini CORI-FLOW ML120 was used, which is the Coriolis instrument with the lowest flow control range in the world. So it is possible to dose even these small gas amounts of NO2.

Check the nitrous oxides (NO2) dosage

The dosed NO2 quantity is checked with the aid of gravimetric measurements. NO2 is transferred via a heated transfer line to a glass U-tube with stopcocks where it is frozen out at -50 °C. The shut-off valves are then closed, the condensate thawed to room temperature and weighed. A total of five different mass flows were tested. The figure shows the result of the check and confirms the very small deviations between the desired and actual dosing quantities. In addition, it can be seen that the mass flow controller operates linearly in the tested range between 0.1 and 4.0 g/h (single points: 0.1; 1.0; 2.5 and 4.0 g/h with error bars drawn in).

no2-dosierung-per-coriolis-massenflussregler-868.jpg

This proves that precise control for small quantities of NO2 can be achieved even at low inlet pressures. As mentioned, nitrogen dioxide (NO2) is a substance of the mixture nitrogen oxides (NOx). Reducing the level of NOx can also be done with Selective Catalytic Reduction (SCR). In case of Selective Catalytic Reduction (SCR) Ammonia or ammonia forming compounds are added to form pure nitrogen and water.

John S. Bulmer (Cambridge University)
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As a scientist at the University of Cambridge, I’m closely involved in a fascinating project on Carbon Nanotubes. In cooperation with Bronkhorst, we are working on a reactor to control the fabrication of this exceptionally strong and conductive material. Let me explain more about this subject and why I consider Carbon Nanotubes to be a material of the future.

History and future of Carbon Nanotubes (CNT)

In the beginning, carbon came in three molecular forms:

  • diamond
  • graphite
  • amorphous carbon Suddenly, in the mid-1980’s, a new molecular form of carbon surfaced in research and ignited the multidisciplinary field of nanotechnology. This all carbon molecule, Buckminsterfullerene, is a nanometre-sized cage of carbon atoms with a molecular structure that resembles a football.

A few years later, another molecular carbon cousin came to light: carbon nanotubes (CNT). Similar to Buckminsterfullerene, the football structure is vastly elongated into a nanometre-wide tube with length millions of times greater than its diameter. Captivating scientific attention; CNT’s strong carbon bonds with its ordered molecular structure make it the strongest material ever made. Electrons glide down CNT’s effortlessly, as stable one-dimensional conductors, which makes CNT’s electrical conductivity four times greater than copper and with a maximum current carrying capacity 1,000 times greater than copper.

3d-model-of-buckminsterfullerence

3D model of Buckminsterfullerene

By the early 2000's, researchers created processes to fabricate textiles composed of CNT’s with densely packed and aligned microstructure. Initially, the bulk properties of CNT textiles lagged well behind the exciting properties of their individual molecules. After steady incremental improvement, the state-of-the-art CNT fibre is as strong as conventional carbon fibre and about four times more conductive. With continued development we expect CNT fibres that are substantially stronger than conventional carbon fibre with an electrical and thermal conductivity greater than traditional metals like Copper and Aluminium.

Application of Carbon Nano Tube fibres is in strain-resistant textiles (protective clothing, bullet-proof vests), composites, construction compounds (ceramics, lighter car bodies) and cables because of their strength. Using carbon nanotubes could have enormous impact on day-to-day life, similar to the way plastics changed the world in the mid-20th century.

Carbon Nanotubes (CNT) at the University of Cambridge

Our laboratory invented a production process that not only creates Carbon Nanotubes in industrially competitive volumes, but does so with unparalleled graphitic perfection into a macroscopic textile with aligned microstructure, all in one production step. This production process is intrinsically simpler than other fibre production processes such as conventional carbon fibre and Kevlar.

The floating catalyst chemical vapour deposition reactor (F-CVD) that is used for this process just requires a carbon source (toluene), a catalyst source (ferrocene) and a Sulphur based promotor (thiophene), which are mixed together and fed into a 1300°C tube reactor by a carrier gas (hydrogen). A floating CNT cloud is formed. Mechanically extracting the CNT cloud out of the tube reactor condenses the cloud into a bulk fibre with aligned microstructure. This is called “CNT spinning”. Specially protected personnel, also known as “the spinner”, mechanically extracts the CNT cloud into a fibre.

Consistent reactor control however, is challenging. The CNT material properties vary substantially between runs and the relationship between controlled and uncontrolled reactor input parameters are not fully understood yet.

Control of the Carbon Nanotubes Reactor

Our program seeks to implement a robust feedback loop to control the reactor’s CNT material properties. Every reactor input variables and output variables, which are specifically selected CNT material properties, are automatically measured and recorded into a database; from the outside weather, to the operating personnel, to the age of the tube, to the precursor concentrations, gas flows, etc.. The database is continually data mined for correlations, parameter interaction, and multidimensional linear regression models that statistically predict reactor behaviour using the data exploratory software JMP™.

For example, figure 1 shows a statistical model for the material’s G:D ratio, this is the ratio between graphite (G) and graphitic defects (D) from Raman spectroscopy, which indicates the degree of graphitic perfection. The model is a function of various reactor input parameters that were found the most statistically significant to the G:D ratio. On the horizontal axis in the plot below, there are the predicted G:D values of the model and, on the vertical, the actual measured vales. In a perfect model with perfect control, we would expect a straight 45 degree line. Clearly, the data points are widely spread along the red line, which indicates a low level of reactor control.

Statistical model for the material’s G:D ratio

Figure 1. Statistical model for the material’s G:D ratio

The setup here involved simply mixing the precursors together (toluene, ferrocene, and thiophene) and injecting the solution into a hydrogen carrier gas via a simple gear pump. It became evident a more sophisticated system was required for greater reactor control.

Bronkhorst solution for control of the Carbon Nanotubes Reactor

Figure 2 shows our improved system. Separate liquid precursors are now independently controlled with Bronkhorst Coriolis instruments (mini CORI-FLOW series)(link product page). The Coriolis mass flow meters give precise mass flow rates without the need of recalibration between different precursors, which greatly facilitates trying out different CNT recipes. Bronkhorst is the only one who succeeded in applying the well-known high-precision Coriolis principle to an extremely small scale by applying MEMS technology.

Carbon Nanotubes Reactor Scheme

Figure 2. Carbon Nanotubes Reactor Scheme

The flow rates are in the range up to 200 g/h for toluene and even below 100 mg/h for thiophene. Hydrogen carrier gases are controlled by robust, plug-and-play Bronkhorst mass flow controllers. Finally, the precisely metered precursors are vaporized and combined with the controlled hydrogen carrier gases with vaporizer technology.

Chemical vapour deposition reactor is much more effective

Figure 3. Chemical vapour deposition reactor is much more effective

With this new and more sophisticated instrumentation, statistical modelling of the floating catalyst chemical vapour deposition reactor is much more effective. Here, the actual versus predicted values for the graphitic perfection are much more agreeable, as is shown in figure 3. This model has substantially less noise, which means the reactor’s response is predictable and repeatable. So far, with this controllable and well modelled reactor system, we have more than doubled typical CNT production rates and tripled the degree of graphitic crystallinity.

Stay tuned! With Bronkhorst and other important commercial, academic, and government partners we hope to surpass conventional carbon fibre soon!

Bronkhorst information

If you are active in reactor technology, do not hesitate to contact us for solutions for your processes. Please contact us for more information.

Chris King
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Anhydrous Ammonia Control for Nitrogen Oxides Reduction

As a technique to reduce the level of Nitrogen Oxides (NOx) in boiler or furnace exhaust gases, Selective Catalytic Reduction (SCR) has been around for years. SCR is a technology which converts Nitrogen Oxides (NOx) with the aid of a catalyst into diatomic Nitrogen (N2) and Water (H2O). A reductant agent is injected into the exhaust stream through a special catalyst. A typical reductant used here is Anhydrous Ammonia (NH3).

A customer of Bronkhorst, who has been selling and servicing boilers and pumps for commercial and industrial applications for over 50 years, had been using a mass flow controller (MFC) which was not reliable and robust enough for the application and thus their customers were suffering from poor ammonia measurement and control.

Selective Catalytic Reduction example

Why use mass flow measurement in Ammonia Control?

Some NOx reduction systems are liquid ammonia based, and others are gas based ammonia. Whatever the state of the ammonia in the NOx reduction system Bronkhorst can offer accurate ammonia measurement and control. Systems in the field today are using the MASS-STREAM (gas), IN-FLOW (gas) and Mini CORI-FLOW (liquid) to accurately control the ammonia being injected into the exhaust gas stream so that proper reaction takes place without ammonia slip. Ammonia slip is when too much ammonia is added to the process and it is exhausted, un-reacted, from the system; effectively sending money out the exhaust stack.

There are very strict federal and state air quality regulations that specify the allowable level of NOx which can be released into the atmosphere and there can be very heavy fines if those levels are exceeded. The company needs to provide their customers with a reliable and robust solution. The application demands a robust and repeatable mass flow controller that is at home in industrial environments.

What kind of Mass Flow Meter or Controller can be used here?

In the NOx reduction system serviced by our customer the mass flow controllers are used to control the flow of anhydrous ammonia (ammonia in gas state) into the exhaust gas of a boiler or furnace where it is adsorbed onto a catalyst. The exhaust gas reacts with the catalyst and ammonia which converts the Nitrogen Oxides into Nitrogen and Water.

Bronkhorst recommended a mass flow controller – from the MASS-STREAM series - using the CTA (Constant Temperature Anemometer) technology which is ideal to avoid clogging in potentially polluted industrial gas applications.

MASS-STREAM mass flow meter

Let me explain a bit about the working principle of this kind of mass flow controller and why it is suitable for an application like this.

The CTA (Constant Temperature Anemometer) principle is essentially a straight tube with only two stainless steel probes (a heater and a temperature sensor) in the gas flow path. A constant temperature difference between the two probes is maintained with the power required to do so being proportional to the mass flow of the gas. This means the MASS-STREAM is less sensitive to dirt, humidity, or other contaminants in the gas, as compared to a by-pass type flow meter that relies on a perfect flow split between two paths. The thru-flow nature of the CTA technology is ideal to avoid clogging in potentially polluted industrial gas applications. The straight flow path and highly repeatable measurement and control capability, combined with the robust IP65 housing, allows the MASS-STREAM to thrive in tough applications.

  • Watch our video animation, explaining the functions and features of the Bronkhorst Mass Flow Meters and Controllers for gases using the CTA principle.
  • Check out the top 5 reasons why to use mass flow controllers with CTA measurement.
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Walter Flamma
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In our previous blog we’ve already discussed many applications at a campsite where Bronkhorst solutions are used. However, we did not mention a very important aspect of camping life; food and beverage. Delicacies like ice cream, soda and candy are also inextricably linked to the summer and to Bronkhorst. Let me explain why…

Ice cream aeration with mass flow controllers

Have you ever celebrated summer holidays without eating ice cream? I didn’t. To create ice cream, aeration in the production process is crucial. This because air makes up anywhere from 30% to 50% of the total volume of ice cream. Higher aeration will produce a tastier and smoother ice cream. A side effect of adding air to ice cream is that it tends to melt more quickly. Thus, for attaining an optimal structure of the ice cream, it is important to have a stable inlet air flow in the production process with a constant cream/air ratio. This can be achieved by using a mass flow controller. If you got a big appetite to read more about the production process of ice cream, please read the blog about the aeration process.

Ice cream

Carbonation process of soda

During the warm days it is important that you stay hydrated. So, a tasty soft drink is by no means a frivolous luxury. The "fssst" you hear when opening a bottle of sparkling soda, is millions of carbon dioxide (CO2) molecules bursting out of their watery prisons, where they have been held against their will. In the soda industry an effective solution is needed to add CO2 gas to liquids, quick and consistent. Soft drink manufacturers add this tingling sensation by forcing carbon dioxide and water into your soda at high pressures, with the help of a thermal mass flow controller for gas. It’s important that the carbonation process is accurate. Inadequate CO2 injection will end in ‘flat’ beverage, while excessive carbonation can possibly break the bottle, which leads to safety issues and loss of product.

carbonation soda

Surface treatment for packaging

Not only beverage itself originates with Bronkhorst products. The packaging used for foods must meet many requirements, whereby flow meters are needed. To extend the shelf life, the packaging must be sterile and oxygen must be eliminated during filling. Also here, an accurate and reproducible flow is very important. Coriolis mass flow meters, CEM (Controlled evaporation mixer) and gas mass flow controllers are the key instruments in these processes. To read more about this process, please read the blog of James Walton, where he explains the sterilization of packaging to extend shelf life.

Additive dosing in candy manufacturing

Certainly the parents among us will know the strong preference of children for candy, due of its sweetness but also because of their attractive colours. During the manufacturing of candy, additives such as colourings, flavourings and acids are added. By using ultrasonic volume flow meters, the accuracy of measurement has been improved, and so is the quality control of the manufacturing process. Many colourings and flavourings are costly agents, and a controlled and efficient use of these substances will gain a better quality product, and will save on raw materials as well.

additive dosing candy manyfacturing

Dosing colourants is not only applicable with foods. When we have finished our diner, there’s one thing everyone runs away from, certainly during vacation…

Dosing colourants in detergent with Coriolis mass flow controllers

Dishwashing; it’s one of the most tedious tasks of camp life, especially when you are used to a dishwasher at home. However, with a little help from Bronkhorst, dishwashing becomes a bit more colourful. Coriolis mass flow controllers are used for dosing colourants (or dye). This applies, among other things, to the production of dishwashing detergent. As well as in flavouring, accuracy and repeatability with dye dosing are of extreme importance for a detergent manufacturer. Every flacon has to be the same colour, you should not see any colour difference between the flacons on the shelves. For this, combining a pump with Coriolis mass flow controllers makes the pump dose mass flow instead of the usual volume flow. Since real mass flow is independent of the fluid properties of the colourant, the accuracy will be inimitable.

dosing colorants in detergent

As you can read Bronkhorst is present in many products at a campsite without you knowing it. Want to learn more about how Bronkhorst is involved in camping life? Read our blog ‘Camping applications that are made possible with mass flow control’.

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Gerhard Bauhuis
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The temperatures are sky high! All winter you've thought about going camping, travelling with your caravan and planning precious family trips. Finally now it’s the time to leave everything behind, and for a moment, forget the busy daily live and struggling at home. However, everywhere you go, Bronkhorst is travelling with you. Bronkhorst plays a role in many more applications than you think, also when you go camping. Let me guide you through some mainstream products you often see at a camping site, and the involvement of mass flow controllers.

Surface treatment

If you are travelling to your holiday destination by car, you will constantly look at some Bronkhorst solutions. Let’s start with the dashboard of your car. Many cars have a leather dashboard; at least, it looks like leather. A major company manufactures ‘skin’ that covers a car's dashboard, to give it this ‘leather look’. The skin is produced by spraying liquid, coloured polyurethane into a nickel mould. A Coriolis mass flow controller combined with a valve forms the basis of this solution to accurately supply external release agent to the nickel mould surface.

Coating of a dashboard But also the foam within the dashboard is manufactured by using Bronkhorst products. To create foam, a gas is added to a mixture, containing acrylonitrile-butadiene-styrene (ABS) or polyvinyl chloride (PVC), to give it the right volume. Too much gas will make the foam unstable, too little and you’ll get a heavy solid block. Therefore, it is utterly important that the correct amount of gas is added with an accurate gas flow controller.

Glass coating

If you look beyond your dashboard, you’ll look through the front window of your car. To control the light transmittance of glass, but also to make glass water repellent, protect it from mechanical and chemical stress, increase the scratch resistance and shatter protection, thermal mass flow controllers are used for the coating process. By controlling individually process gas flows, film thickness uniformity improvements are achieved.

Coating on headlights

When polycarbonate was introduced as a replacement for headlights glass in the early 1980s, new problems arised. Headlights are subject to a harsh environment. Due to the position in the front of a car, critical parameters for lifetime and performance are weather ability, scratches and abrasion. To protect headlights from these factors, scratch and abrasion coatings have been developed that are sprayed on the headlights with the help of robots in which Coriolis mass flow controllers control the flow to the spraying nozzles.

Hydrophobic coating

However, surface treatment is not only applicable for glass and dashboards. If you have experience with camping, you will be familiar with how fierce the summer weather sometimes can be. The awning of your caravan needs to be water repellent - this also applies to your raincoat - to sustain the heavy rainfall now and then. To make fabrics and textiles hydrophobic, Empa - a research institute of the ETH Domain, applies plasma polymerisation to deposit thin, nanoscale layers on top of fabrics and fibers. For this, they are using a Controlled Evaporation and Mixing system, in short a CEM system. In one of our previous blogs ‘Hydrophobic coating, the answer to exercising in the rain’ you can read about this application.

Mass flow controllers are used to make awnings hydrophobic Mass flow controllers are used to make awnings hydrophobic

Odoration

Bronkhorst is also involved with many smaller attributes you will encounter on a campingsite. Most people still enjoy the comfort of gas for heating or cooking on the stove. But also with gas we are able to fire up the barbecue in no time at all, in comparison with the old-fashioned briquettes that are sometimes hard to ignite. When gas escapes from a pressurized cylinder, you’ll recognize this from its penetrating scent. However, like Sandra Wassink stated in her blog “How mass flow controllers make our gas smell”, natural gas is odorless. By controlled supply of odorants like Tetrahydrothiophene (THT) or Mecaptan with a mass flow controller, the scent is added to the natural gas on purpose.

Barbecue

Let’s stay with the topic scent for a moment. For when we want to decrease the amount of mosquitos in our surroundings, we often enlight a citronella candle when we are getting tired of using the flyswatter. With the CORI-FILL dosing technology, Bronkhorst offers an easy-to-use setup to dose fragrances, like citronella, in candles. The addition of fragrance to a candle should be carefully monitored to ensure the candle burns cleanly and safely. To read in more detail about the production of scented candles, please read the blog of Graham Todd.

LED lighting

However a candle can bring much light to your surroundings, you won’t take a candle with you when you haste to the camping toilets at night. Instead you will use a flashlight of course. The working principle of the LED (Light Emitting Diode) inside this flashlight is a technology where Bronkhorst plays its part. LED works via the phenomenon called electroluminescence, which is the emission of light from a semiconductor (diode) under the influence of an electric field. By applying a semiconducting material like Gallium arsenide phosphide for instance, the manufacturing of red, orange and yellow light emitting diodes is possible.

Flashlight

I already told you so much, but frankly, just a tiny bit of all the camping applications we are involved at. Hopefully you got some more insights on the importance of Bronkhorst in many industries, also when you go camping.

If you want more information concerning the discussed applications, please contact us.

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