Power washing generates large volumes of contaminated run-off and aerosols, presenting a hazard when used e.g. cleaning sewage systems or nuclear contamination. One of the main pieces of equipment currently used for industrial cleaning, ultrasonic cleaning baths, can only clean objects small enough to fit in them and the devices to be cleaned sit in a soup of contaminated liquid. Neither power washing (high-power pressure washing) nor ultrasonic cleaning baths can easily be scaled up and neither can be used on delicate materials such as hands or salad.
“Society runs on its ability to clean. Ineffective cleaning leads to food poisoning; failure of manufactured products such as precision watches and microchips; and poor construction – from shipbuilding to space shuttles – since dirty surfaces do not bond. The impact in healthcare is huge – hospital-acquired infections, from instruments that aren’t properly cleaned, cost the NHS £1 billion per year. There’s a very obvious need for technologies that improve our ability to clean while saving on our most important resources, water and energy.”
Currently, industry uses excessive water, power and additives for cleaning. For example, it can take up to 100 tonnes of water to produce 1 tonne of clean wool after shearing. Many industrial processes also generate large quantities of contaminated run-off. The water from hosing down an abattoir represents a real health risk and cannot be allowed to enter the water supply. Purifying run-off is costly – each cubic metre of water used for cleaning in the nuclear industry can cost around £10,000 to subsequently treat.