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Repurposing Old Breast Pumps to Meet Ventilator Demand

Breast Pump Ventilator

The Issue at Hand

The respiratory impacts of the COVID-19 virus have made ventilators one of the most needed medical devices in hospitals. As of April 5th, the New York City Mayor Bill de Blasio warned that the city would run out of ventilators in a matter of days. Luckily, just over 3 weeks after his warning, New York has been able to keep up with demand and is now giving away extra ventilators to other areas in need.

Nonetheless, this issue caught the attention of some engineers who wanted to make a difference. Located in Maryland, Brandi Gerstner, Grant Gerstner, Alex Scott, and Rachel LaBatt modified breast pumps to create temporary ventilators and free up higher-quality ones for those who need them the most.

The Solution

To create temporary ventilators, the team needed to produce medical-grade equipment at a low cost. Following the FDA’s approval for the use of positive-pressure emergency medical equipment, Gerstner had an idea: why not try a breast pump?

The closed-loop compressor combined with a medically-based production process made the breast pump an ideal choice for a ventilator. One issue, however, was that breast pumps sucked instead of pumped. To remedy this, Gerstner broke into one of her old breast pumps and found a way to easily reverse its air-flow. To further increase its accuracy, the team soldered some pins into the pump’s electrical board and used an Arduino to control its operation.

The prototype costs about $250 to produce, which is incredibly low when compared to the $25,000 cost of a medical ventilator. While the team is well-aware their pump adaptation will not provide the same services as a high-end medical ventilator, they seek to ‘fill the gap’ and make the higher-quality ventilators more available to those who need them.

The Implementation

To ensure user safety, the ‘breath pump‘ team is working to improve and test their pump before releasing the designs. They are currently working with a pulmonologist to create a better design more suited for medical use. For FDA approval, the device will also need to be tested in a biomedical simulation lab.

Once their design gains FDA approval, the team will release their modifications in an open-source format. Unconcerned about monetary gain, they simply want to “make a difference.” While the ventilator shortage has become less of an issue, engineers like Gerstner and her team will make a large impact in the fight against COVID-19.

Green Innovation: The Smog Free Tower

Smog Free Tower

In my last post, I discussed the Dearman Engine, which posed a viable solution to the NOx emission problem. However, NOx gases are only a small part of a bigger issue: smog. Smog is produced through the burning of fossil fuels and their derivatives, and it contains a large assortment of particulates and greenhouse gasses.

Because smog is such an issue, I would like to discuss a proposed solution: the Smog Free Tower.

The tower is the work product of Dutch visionary Daan Roosegaarde and his team at Studio Roosegaarde as well as the company ENS Clean Air. Studio Roosegaarde, started in 2007, aims to find innovative ways to solve today’s environmental issues. The tower is but one of their many projects.

The Smog Free Tower

At 7 meters tall, the Smog Free Tower is designed to clean air saturated with smog. The tower does this through a process called positive ionization, which I will discuss later. Using this technique, the tower filters around 30,000 cubic meters of air every hour.

More important than capacity, however, is effectiveness. In a 2017 study completed by the Eindhoven University of Technology, the tower was said to eliminate 70% of PM10 and 50% of PM2.5 from the processed air. PM10 and PM2.5 refer to the diameter of particulate matter in microns.

Before this study, the tower went on a tour of China in 2016 to test its operation in high-smog environments. Throughout the tour, the tower functioned extremely well in a variety of locations. The success of this tour, combined with the promising results of the Eindhoven study, go far in arguing for the validity of this technology.

Still, we must ask ourselves: how does it work?

Positive Ionization

The tower processes smog in the air through principles of positive ionization. Air ionization, a well-documented practice, can be used in many applications, including the reduction of static electricity and separation of particulates from the air. Although the company’s positive ionization process is not specifically discussed, I decided to apply the principles of air ionization to attempt an explanation.

When an AC current is applied to the air, positive and negative ions are created. With a DC current, however, it is possible to create only positive or only negative ions. The process of positive ionization likely refers to the former of these two options.

The positively ionized air (primarily oxygen, nitrogen, and argon) attracts the polar compounds in smog – CO, NOx, and others. These compounds gather around the ion, clumping together and weighing it down. This not only creates larger particulates, it also helps to separate them from the air.

While the description of this process is speculative, derived from the descriptions of air ionization technology, its results are supported by ENS’s description of the system. They claim the “positive ionization technology [is used] to capture fine dust and transform it into coarse dust.” As explained in my theorized description of the process, the particles will gather and grow in size — growing from fine dust to coarse dust.

Although my description is not based on any actual information released from the company, it may portray at least a semi-accurate account of the technology.

Other Smog-Related Projects

In addition to their Smog Free Tower, Roosegaarde has two more initiatives for their Smog Free campaign. Both are designed to increase awareness of their brand and encourage the reduction of smog.

The first, a Smog Free Ring, is derived from the Smog Free Tower. The ring’s ‘stone’ takes the form of a small cube of smog encased within a larger, clear cube. The smog represents 1,000 cubic meters of filtered air, and is currently a permanent exhibit in 3 museums. Purchased by many couples, the ring costs $294.

The second venture, the Smog Free Bicycle, uses a mountable filter to clean air for the rider. The filter takes in air from the front end, filters it, and exhausts the clean air around the rider. The studio hopes to have bike share companies use this technology as a standard within cities.

Just as for the environment, there is also much benefit for the rider. He or she will now have fresh air blown into his or her face, making a smog-filled day more than rideable!

Cleaner Air, Better Future

The smog free tower, along with its counterparts, is a fantastic step in the right direction. The different designs are portable, easy to incorporate, and perform their function admirably. With more Smog Free campaigns and technologies to match, our atmosphere may just survive the future.

Green Innovation: The Dearman Engine

The Dearman Engine

The Dearman Engine

The Problem

It is no great secret that our well-being is tied to, among other things, the contents of our air. Currently, cars, coal-burning plants, diesel-powered machines, and more are releasing dangerous amounts of Nitrogen Oxides, or variants of NOx, into our atmosphere. These chemical compounds are known green house gasses and also serve as long-term health risks.

This is clearly an issue, but what are we doing to solve it? One tech company, Dearman, has designed a new engine for peripheral systems . The so-called Dearman engine will be able to replace many diesel counterparts in cooling, heating, and power applications.

The Engine

The Dearman engine draws information from the Industrial Revolution’s steam engines – but with a twist. Instead of heating water, causing it to expand and push a piston, the engine heats up liquid nitrogen with air and hot water. During this process, the liquid nitrogen expands to 710 times its initial volume, making it much more effective than steam engines. Click on the image below to see the process as a GIF.

The engine works much like current combustion engines. As portrayed in the images below, there are 4 main stages to the stroking process. The first step of this process begins when the piston is in its ‘Return Stroke’. During this time, the piston pulls warm water into the chamber.

During the upstroke, the water is compressed and, in a position described as ‘Top Dead Centre’, the liquid nitrogen is pumped into the chamber. The nitrogen becomes gaseous, expanding rapidly with a relatively stable temperature (the reaction is largely isothermic).

The expansion of the gas pushes the piston down in the ‘Power Stroke’, turning the drive shaft. Finally, the momentum of the drive shaft pushes the piston upwards, expelling the gas and water out of the chamber. The piston then travels downwards, and the process begins again.

The Environment

Most engines emit CO2 and NOx gasses, which are harmful to the environment — and your health! The Dearman engine, however, solves this issue. The now-cooled water is recycled within the system and the nitrogen gas is exhausted. Atmospheric nitrogen, which has decreased as a result of human civilization (replaced by nitrogen compounds), is extremely beneficial to the ecosystem.

This engine not only ceases to emit nitrogen compounds, it also emits much-needed nitrogen back into the atmosphere.

The Applications

Dearman has already begun using their engine to power a variety of systems. Under the projects section of the website, the company discusses their current ventures.

The Transport Refrigeration Unit (TRU): The Dearman Engine, with its liquid nitrogen system, is ideal for cooling applications. The engine is quieter, quicker, and more efficient than its diesel counterparts — plus its clean!

The Dearman Generator (Genset): While the Dearman Genset is still in its design phases, the company hopes it will surpass diesel generators in both efficiency and emissions. The generator, because its functioning is liquid-nitrogen-based, will also provide a unique service to environments that need special cooling.

The Dearman Heat Hybrid (DHH): The Dearman Heat Hybrid is the company’s vision of a diesel-Dearman hybrid. The waste heat generated by the diesel engine can be used by the Dearman engine to increase its efficiency. Already, there has been rigorous testing of a large hybrid bus, with promising results.

The Future

The Dearman engine promises much, but it still has a long way to go. A big leap will occur when the engine gains enough power to fully operate a car — and it is only a matter of time. As mentioned above, the company has already successfully tested a hybrid engine for a bus. Technologies like the Dearman engine are entering the market at an encouraging rate, and it seems many of them are promising increased efficiency over their polluting counterparts.

 

Part 3: Washing and Resizing

Part 3 of Green Innovation: Recycling Plastics Series

Washing

The washing process can be completed many ways, with the main focus to remove non-plastic contaminants. For example, PRM sells many types of washers for plastic films which can be used individually or together. These include the Hot Water Washer and the Friction Washer.

The Hot Water Washer: The PRM’s Hot Water Washer works by sending plastic flakes (specifically PET) horizontally through the machine. As they travel, they are sprayed with hot water and sterilized.

The Friction Washer: Much like the hot water washer, the plastic – again PET – is sprayed with hot water as it travels throughout the machine. This time, however, the plastic is fed into the bottom of an inclined, mesh-walled cylinder. The cylinder, spinning at around 1000 rpm, flings small contaminants through the mesh and causes the plastic pieces to rub against each other, scraping of dirt and grime.

Resizing

During the resizing process, plastics are cut into much smaller pieces. This makes storage and processing both easier and more efficient. In fact, although it has been posted later in the list, it often occurs before the washing process.

In PRM’s plant recycling line, for example, they use an assortment of machinery to cut plastic films down to 10 – 20 mm in size. To learn more about the resizing equipment they use, check out the size-reduction section of their website.

Stay Tuned for Part 4 of the Green Innovation: Plastics Recycling Series!

Part 2: Sorting

Part 2 of Green Innovation: Recycling Plastics Series

The bulk of sorting, at least at the consumer-level, is done by the plastic collection agencies. However, in industrial-scale recycling – where businesses sometimes send their plastics without sorting them – different methods are used. Northstar’s article on the subject discusses how these plastics can be sorted with water and heat.

By placing plastics in water, their density (relative to water) can be determined. Typically, LDPE, HDPE, and PP plastics will sink while PET, PVC, and PS plastics will float.

When heating the plastics with a flame, the plastic’s identification is more precise. The plastics that float should also produce a blue flame with white smoke. Those that have a waxy smell are usually LDPE or HDPE, but the plastic with a sweet smell is typically PP.

Of the plastics that typically sink, each has their own properties when burning. If, when melting, it has a burnt-sugar smell, the plastic is likely PET. If the plastic ignites only at higher temperatures (with a blue/green flame), it is likely PVC. Finally, if the plastic does not drip and has black, sooty smoke, it is likely PS.

It’s pretty clear, however, that this process is time-consuming and inefficient for large batches of unsorted plastics. To solve this issue, a group of researchers designed a way to process almost 1.4 tonnes of plastic every hour – with computers.

They use the unique fluorescence patterns of plastics to identify and separate them. For more information on the process check out this research paper. In the future, I may create a post about the topic, so stay ready!

If you liked this post, be prepared for Part 3 of the Green Innovation: Plastics Recycling series.

Part 1: Recycling Plastics Overview

Part 1 of Green Innovation: Recycling Plastics Series

In 2017, roughly 267.8 million tons of waste were generated by the American population. Of the 35.3 million tons of plastic, only 2.92 million tons were recycled or composted. For more information on these statistics, check out the EPA’s 2017 report.

While it would be nice to see the amount of recycled plastic increase, there is still a lingering question: what happens to the plastic that is recycled?

The plastic-recycling can be easily separated into a series of 6 steps:

  1. Collection: This step is the most well-known, and it involves all the recycling collection processes including government services, bins in public spaces, and more.
  2. Sorting: Machines sort the plastics to find which ones the plant can process and to prevent damaging the equipment or slowing the process.
  3. Washing: This step is used to remove impurities, including labels, dirt, residue, and other non-plastic things.
  4. Resizing: During this stage, the plastics are ground-up to make processing more efficient and remove possible impurities unaffected by the last step.
  5. Identification and Separation: Here, the plastic chunks are separated by their different properties in processes that will be discussed later.
  6. Compounding: During this phase, the plastic bits are combined into pellets which are then used in the manufacturing of plastic products.

In the following posts, I will discuss each in greater detail. The collection process, however, is quite straight-forward and is discussed below.

Collection

The collection process, as mentioned above, is quite simple. Plastics are collected through a variety collection methods, including trash services (retrieving designated RECYCLE-ONLY bins), non-for-profits, and recycling bins. The real “meat” of the process occurs in the following steps.

Stay posted for Part 2 of the Green Innovations: Plastics Recycling Series.

Green Innovations: Recycling Plastics Series

Walking down the street or within many buildings, you may see these odd-looking bins with a circle of arrows on them. Of course, these bins are not mysterious, and neither is their purpose. We use recycling bins to send our unneeded plastic, glass, and paper to the magical land of recycling factories, where they are converted into those “recycled” products we love to buy.

The recycling process, however, is not quite as simple as magic. As a matter of fact, it is a complex process that requires the use of highly-specialized machinery.

There is a recycling process for dozens of materials, but, to keep it simple, I will only begin by discussing the recycling process for a commonly used material: plastic. Furthermore, this discussion will likely miss some information on the process. For a more complete picture, let these posts serve as a gateway to research – and feel free to start with the included references throughout the entries.

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