Bubble-capturing surface helps get rid of foam
In many industrial processes, such as in bioreactors that produce fuels or pharmaceuticals, foam can get in the way. Frothy bubbles can take up a lot of space, limiting the volume available for making the product and sometimes gumming up pipes and valves or damaging living cells. Companies spend an estimated $3 billion a year on chemical additives called defoamers, but these can affect the purity of the product and may require extra processing steps for their removal. Now, researchers at MIT have come up with a simple, inexpensive, and completely passive system for reducing or eliminating the foam buildup, using bubble-attracting sheets of specially textured mesh that make bubbles collapse as fast as they form. The new process is described in the journal Advanced Materials Interfaces, in a paper by recent graduate Leonid Rapoport PhD ’18, visiting student Theo Emmerich, and professor of mechanical engineering Kripa Varanasi. The new system uses...