As Bio-Brussels we are trying to find a more sustainable and effective way
to better deal with hard water
Why are we doing this?
Because hard water causes a lot of problems, both on a large scale such
as in industry as on a small scale in your homes. And when we say
problems of scale we mean that very literally: limescale to be precise.
Indeed, hard water means nothing more than “water that contains a lot of
minerals”, of which magnesium and calcium are most impactful when
talking about water hardness, because these two can form insoluble
carbonates aka yes, you guessed it, limescale.
What’s so bad about limescale?
This limescale can have detrimental effects on all appliances that come
into contact with water such as pipes, boilers, heat exchangers, dish
washers, washing machines… because it causes narrowing, and in extreme
cases complete blocking, of the pipes and, additionally, lowers the
efficiency of heat transfer by boilers and heat exchangers. Removing the
scale is a very costly and difficult process, especially on industrial
scale (Donaldson & Grimes, 1988).
And it ruins your hair too? No thank you!
Chemically the presence of these ions can cause trouble under the form
of soap scum (calcium salts of long chain fatty acids), which not only
forms undesired deposits on for example clothing but also lead to a
higher soap demand for the same degree of cleanliness. (Soontravanisch
et al., 2010). It has also been suggested that these deposits can form on
hair leading to it looking dry and less healthy, as well as on the skin
leading to irritation and dryness (Doan & Nong).
Okay, I want to get rid of hard water in my house, what can I do?
Up until now, there aren’t really any efficient or sustainable ways
to make water softer. Most commonly, ion exchange chromatography is
used. This technique is based on a negatively charged resin with
sodium ions in which the calcium replaces the sodium and sticks to
the resin so that no insoluble carbonates can be formed. Check out
the image we made for a more schematic overview of how this all
works! The sodium however remains part of the softened water
(Alexandratos, 2009). This leads to another undesirable phenomenon:
salination (Overbo & Heger, 2019).
With our IGEM project we hope to develop a 100% biological water
softener.
How did we come to this idea?
We really wanted to focus on an issue local to Belgium, and since
our university is from Brussels and we learned so much in this city,
we wanted to do a project that gave back to it. When Jonas and Wael
suggested this brilliant idea, we got really excited about it. And
after a few more brainstorming sessions and introducing chickens and
eggs into the conversation it was safe to say that everyone wanted
to go full steam ahead on developing something like this. Chickens
and eggs you ask? Well, it is actually so that the shell of eggs is
made from those insoluble carbonates we keep mentioning and chickens
posses special enzymes to induce formation of these carbonates,
allowing them to produce the shell. This fun little fact was later
also used as the inspiration for our team logo.
If chickens can do it, coral reefs can too!
Finding out about the egg, we wanted to look into what other natural
systems are made from calcium carbonate, so that we could find even
more crystallizing enzymes. We screened the entire animal kingdom,
from corals to humans, for these types of proteins and found plenty
of potential candidates! We’re expressing all of those in a very
stable protein scaffold, separating the formed proteins from the
producing cells and using those as a dried paste in system where the
water passes through,
Here's a schematic overview
