Researchers University of Cape Town (UCT) master’s student developed the first bio-brick from human urine.
Tackling waste recovery, scientists have found an innovative technique to assemble bio-bricks through a natural process called microbial carbonate precipitation. This development could boost the management of waste material by many folds. Dr. Dyllon Randall, a senior lecturer in water quality engineering at UCT, said, “the bio-bricks are created through a natural process called microbial carbonate precipitation. It’s not unlike the way seashells are formed.”
The discovery was made by a master’s student in civil engineering at the University of Cape Town Suzanne Lambert. The process called microbial carbonate precipitation, uses the loose sands to colonize with bacteria, which then secrete the enzyme, urease. The enzyme urease breaks the urea present in urine to form calcium carbonate through a complex chemical reaction. In this process the sands get cemented into any desired shape.
Ranadall explains about the working of the process as, “if a client wanted a brick stronger than a 40 percent limestone brick, you would allow the bacteria to make the solid stronger by ‘growing’ it for longer. The longer you allow the little bacteria to make the cement, the stronger the product is going to be. We can optimise that process.”
The success of this process is highly commendable as it would check the increasing pollution from brick kilns. The bio-bricks are made in moulds at room temperature, without producing any harmful gases. Moreover, bio-bricks manufacturing generates nitrogen and potassium as by-products, which are important components of commercial fertilizers.