Canadian scientists from Saltworks Technologies have recently discovered a new technology for water desalination. The process reduces the electrical energy consumption needed by the process by 70%. Saltworks Technologies reported that they can produce 1 cubic meter of fresh water using just 1kWh compared to 3.7kWh per cubic meter achievable using reverse osmosis.
But how does the actual technology really work? Simple: solar heat or waste heat is used to evaporate water and concentrate salt water. As a fact, solar energy is converted into osmotic energy and the resulted osmotic energy is used to desalinate water. The concentrated salt water is exposed to two separate solutions of regular salt water via two different ‘bridges’, one which is porous to chloride ion and the other which is porous to sodium ions.
Sodium and chloride ion are able to migrated across the bridges into the salt water solution. The two elements have the role to equalize the difference in ion concentration between the two solutions. In this way the two solutions get charged positively with the sodium ions and negatively with the chloride ion. To continue the process, the resulted solutions are exposed across two similar bridges to the water to be desalinated.
Sodium ions are attracted into the chloride solution and chloride ions into the sodium solution (different changes attract themselves) resulting desalination. The 1kWh energy used in the process for 1 cubic meter of water, comes mainly from pumping fluids around the pipework. To reduce costs, plastic pipes can be used instead of steel pipes as the system in not working under high pressure.
Let’s wish all the best to Saltworks Technologies and their smart desalination process, and let’s hope we’ll see this system very soon on the market.