Biomanufacturing replaces coal-fired brick kilns with room-temp bacteria and sand

The coal-fired baking of bricks generates more CO2 annually than the entire aviation industry. A biomanufacturing process aims to change that, replacing fire with a mixture of non-pathogenic bacteria and sand. It's cheap, and the inventor, Professor Ginger Dosier, says it produces better and more sustainable bricks.

There are over 1.3 trillion bricks manufactured each year worldwide, and over 10% are made by hand in coal-fired ovens. On average, the baking process emits 1.4 pounds of carbon per brick - more than the world's entire aviation fleet. In countries like India and China, outdated coal-fired brick kilns consume more energy, emit more carbon, and produce great quantities of particulate air pollution. Dosier's process replaces baking with simple mixing, and because it is low-tech (apart from the production of the bacterial activate), can be done onsite in localities without modern infrastructure. The process uses no heat at all:mixing sand and non-pathogenic bacteria (sporosar) and putting the mixture into molds. The bacteria induce calcite precipitation in the sand and yield bricks with sandstone-like properties. If biomanufactured bricks replaced each new brick on the planet, it would save nearly 800 million tons of CO2 annually.
Biomanufactured Brick: Bricks Without Clay or Carbon (via Beyond the Beyond)


  1. The article fails to mention how long it takes to make the brick this way vs. how long it takes to make with fire. I suspect that would be a rather important tidbit of information. The fact that it’s lacking makes me suspect that this new process is much much slower. Would be nice to be proven wrong, though.

    1. The article fails to mention how long it takes to make the brick this way vs. how long it takes to make with fire

      About a week, compared to a couple of days for fired bricks.

      Apparently, it’s not just sand & bacteria, it’s sand, bacteria, calcium chloride and urea. And it requires emissions processing to prevent ammonia and nitrous oxide pollution. Ooops.

    2. Judging from the photographs, it looks like the process takes no longer than the time it takes for the brick to dry. That’s about the same amount of time as it takes to form a clay brick. And because the bricks don’t need firing, the entire process should be considerably shorter.

      Of course, they could be remoistening the bricks to give the bacteria more time to work, but that doesn’t show up in the photo.

      This invention really fired up my imagination. It’d be wonderful if we knew more about the process and the bricks themselves. Does the ratio of sand to bacteria solution have to be perfect? What happens if the solution is spilled on the ground? Do you have to make bricks, or can you use forms (like we currently do with concrete)? How do the sandstone-like bricks compare to the coal-fired bricks currently in use? How do users create/transport/store the bacteria? Does it take special equipment, like refrigerators or vacuum-sealed packaging?

      What an interesting invention!

    3. I’ve been through the process of making conventional bricks for large scale construction projects in Africa and the reality of conventional bricks is the the drying stage, after they are moulded but before they are fired, takes about 6 months.

      So even though the firing only takes about 12 hours, the whole process is very time consuming.

      Now the mould is not occupied during the whole period of time during which the bricks are being made by conventional means, unlike here where the mould is needed, but one can envision simple ways of building inexpensive multi-cavity moulds using planks constructed into a trough with spacers.

      Having seen the time, resources, and labour that go into the conventional process I am very excited to try this out and can’t say enough how much a difference it might make.

    4. to sean :

      the process in 40 degree Cecilius is about 45 hours for 1 Mpa strength for up to 18Mpa you need about 28 days!

  2. Bricks without straw?!?!

    OK, Anyway…
    I want to try this, it sure beats trying to gather or buy the fuel, especially since open flame is illegal most of the time.

  3. I’ll second the question about time.

    Also – what is the strength of these bricks? Are the much stronger than mud & straw mixed and left to bake in the sun?

  4. Only ten percent of bricks made worldwide are fired. From the photo, I really doubt that this bio-brick is comparable to a fired brick in strength or durability, but is it even as good as a standard adobe brick or a compressed earth brick?

  5. It would be really neat (although terrible for the ecosystem) to see an entire desert be converted to stone by out-of-control spread of the bacteria.

  6. The other big questions:

    Where does the bacteria come from? Fire is easy to make, bacteria may require advanced infrastructure.

    Is the process encumbered in any way by patents?

    The article seems pretty vague on all the key details.

    1. Bacteria is generally pretty easily transported through a starter culture. A little bit goes quite a long way, as they’re self replicating, typically reproducing incredibly fast. Like a sourdough starter culture, a little dab will do you indefinitely, as long as you keep it clean. This is a spore forming variety, these are typically pretty hardy, usually surprisingly hardy. You could probably bake it and kill off everything that isn’t a spore forming bacteria.

      Wondering if bacterial mutations/strains exist that would do the job faster.

  7. It seems like a waste to make bricks with this process. If the shape of your future sandstone is governed only by where wet sand may go, why make little rectangles? Shouldn’t you save time and cast the whole house in one go?

  8. What is the metabolic byproduct of the bacteria? If it’s CO2, we may be no better off than where we started

    1. To anon
      Co2 that produce by this bacteria used in formation and precipitation of CaCo3(calcite crystals).

  9. Err, the numbers above for CO2 emissions appear to be grossly exaggerated. The claimed number of 800 million tons of CO2 a year is only possible if every single brick fired in the world is made using 1.4 pounds of coal. This seems unlikely to me, especially in places like India where a significant fraction of bricks must be made using biomass fuels (like cow dung and straw, the norm in many instances). What is the justification for this figure, or is it just good ad copy?

  10. >> apart from the production of the bacterial activate

    How is this manufactured? How much does it cost? Where is it made? And how is it transported to the brick making site?

    The article linked to above does not provide this information.

  11. The information provided is disappointingly inadequate. The photos show a miracle liquid being poured on sand, but how many hundreds of gallons of this liquid are required to build a structure? And if a starter culture can produce the hundreds of gallons, what kind of equipment is necessary on site? Some plastic buckets or much more intensive machinery?

  12. This will ONLY work if it’s cheaper to make bricks this way. Relying on the good nature of contractors and manufacturers to pay more for “green” bricks is not a good bet to make. It’s nice to see tech like this but as with almost everything it’s about the Benjamins.

    1. Isn’t the Benjamin return dependent on things like economies of scale? Doesn’t most tech, green or not, require people buying in to the idea to create the infrastructure or supply chains to make a technology affordable. As far as green tech goes (like compared to solar panels), this looks like it could have a pretty low economic moment of inertia. Then again, is it better than adobe? That’s a reasonable question.

  13. Of course it depends on the type of brick it makes…

    Could this brick be used below grade? Does it have the same strength properties as a fired brick? Could you make pavers this way?

    In many ways it looks like a modified compressed earth block setup. And if so then it does have some limitations…

Comments are closed.