Artveoli combines algae and microfluidics to generate fresh air indoors
Live in any major city, be it London, Paris, Los Angeles or Shanghai, and you’ll be all too aware that air pollution is a huge and growing problem. At the same time, indoor air quality can suffer because of attempts to reduce buildings’ energy consumption to make them less pollutive to the outdoor environment — by, for example, applying high-grade insulation and recirculating indoor air to reduce heat loss/lower air conditioning systems’ energy needs. Very well sealed buildings can lead to elevated CO2 levels as more people gather indoors. So how to square this circle?
Step forward Artveoli, a biotech startup that’s building an air purifying device that aims to convert carbon dioxide into oxygen in indoor environments, such as offices and homes, by harnessing the photosynthetic properties of algae. “It’s like having trees inside buildings,” is Artveoli’s elevator pitch. The startup is officially launching onstage at TechCrunch Disrupt New York, opening registrations for people to sign up for updates.
The aim is to start manufacturing its first air purifying product this year, says co-founder Alina Adams — with a view to shipping the device sometime in 2017. Adams has a background in microfluidics, the core technology which it’s applying to increase the efficiency of the algae to enable a single unit to have an impact on the room where it is placed — having worked at the Stanford Microfluidics Foundry, along with her co-founder.
Microfluidics refers to a field of research that looks at how fluids behave differently at the microscale and how those differences can be exploited for particular use-cases. “It’s a new type of technology that makes biochemical processes much easier, faster, it’s easier to control and work with the different, complex biological systems,” explains Adams.
“I was thinking, we have plants that make fresh air so how can we put lots and lots of plants inside buildings?” she adds, discussing how the idea for the business was born. “This was an ah-ha moment — ok nobody is actually using microfluidics devices to grow photosynthetic type of cells to make fresh air.”
An existing technology — photobioreactors — uses a light source to cultivate phototropic microorganisms, such as algae, generating biomass from light and carbon dioxide. But these units tend to need to be very large in order to generate a large amount of biomass. Artveoli’s founders’ mental leap was to wonder whether they could grow the same type of phototropic cells on the micro-scale — so very, very densely packed, and thus able to pump out more oxygen.
“We’re working with small channels and small volumes, so we’re working with chips that are easier to manipulate small volume type of liquids. High density means we’re using cell concentrations inside our system that are much, much more significant than those that you’d find even in traditional bioreactors.
“So we have these nature-type of systems inside that metabolically produces oxygen and removes carbon dioxide… Light powers the system. And because we have this large surface area and high density that’s how we’re able to achieve significantly higher outputs for carbon dioxide absorption and oxygen production than traditional trees.”
Adams says NASA has already looked at using the same type of algae it is putting inside its microfluidic high-density photobioreactors to power closed, self-sustaining systems to produce oxygen for astronauts on long space missions. However, the problem they ran into was making those systems efficient enough.
“They’re not able to get this efficiency because they’re using larger volumes. That’s where microfluidic technology eliminates that problem. With microfluidic technology we have more control and we have the higher efficiency, so they can work with higher densities,” she adds.
“We’re actually talking to DARPA — they are interested in potential future applications for this technology — because we are able to produce oxygen and remove carbon dioxide in closed spaces. Which is essential if you’re limited on the air supply from outside.”
Artveoli’s device is also a closed system (which lowers the risk of contamination), with the algae contained inside transparent, microfluidic plastic chips and the necessary nutrients (plus light, via an LED backlit panel) fed to them via a built-in control system. This allows for control of cell density (and therefore unit efficiency), including by controlling the rate of introduction of new algae, based on the growth rates of the existing population.
The particular microalgae being used by Artveoli has been selected because it has a high photosynthetic efficiency, says Adams. “We introduce the right proportions of media — that’s part of the control that we have, so we can have a very stable system.”
The algae won’t live forever, of course, even given ideal conditions provided for them in a closed system, so there is a need to remove waste (i.e. dead) algae from the units by replacing filters in the units and also replenishing with fresh microalgae over time. But the aim is to make this process very simple — similar to putting a new ink cartridge in a printer, says Adams.
“We remove the excess biomass, or bioproduct waste, which is basically dead algae,” she says. “And introducing — similar to printer cartridge models — you put in new media.
“There’s no periods whenever there’s no algae in the system so it’s continuously recirculating and introducing new media and removing the excess and dead cells/debris out with the cartridges.”
These (biodegradable) cartridges will need to be replaced three to four times per year, providing for a recurring revenue stream for the business. The cost of the cartridges will be similar to the price of new filters for existing air purifying machines, according to Adams.
Source: http://techcrunch.com