# Micro-Nanobubble Technology in Surface Cleaning and Defouling
## 3 Advanced Applications of NBs in Precision Surface Cleaning
### NBs in Membrane Cleaning  
Membrane corrosion has a major impact on system efficiency and operating costs in industrial processes, wastewater treatment, and water treatment. The application of NB technology for fouling reduction and membrane cleaning is a viable and environmentally beneficial alternative [44]. Owing to their special qualities, which include high surface energy, ROS production, and small size, NBs have proven effective in avoiding and eliminating fouling layers, improving membrane performance, and reducing the need for chemical cleaning agents [34]. [PERSON] et al. [25] examined and compared the use of air MNBs with traditional antiscalants as a chemical-free technique to control the production of scale (CaCO\({}_{3}\) and CaSO\({}_{4}\)) on seawater reverse osmosis (SWRO) membranes. With values of 86.5% for CaCO\({}_{3}\) and 83.0% for CaSO\({}_{4}\) solutions, greater than the fluxes obtained with antiscalants (63.5% and 55.8%, respectively), the results showed that MNBs were more successful in preserving the permeate flux. While crystals were present without MNBs, scanning electron microscopy analysis (SEM) pictures demonstrated that MNBs inhibited the production of calcium crystals on membranes. It has been shown that MNBs, which have a negative surface charge and range in size from 90 to 900 nm, can enhance membrane permeability and regulate scaling without the use of chemicals. By providing a chemical-free substitute for SWRO operations, this strategy lowers operational expenses and the negative environmental effects of chemical use. [PERSON] et al. [45] examined the effects of emitter types and micro-/nano-aeration treatments on drip emitter clogging. According to these findings, the blockage started initially and quickly accelerated, eventually resulting in severe or total clogging. Owing to the considerable inhibition of the emitter blockage caused by micro-/nano-aeration, the typical working times of the emitters increased by 38%, 20%, 30%, 28%, and 130%, respectively. The clogging times were the shortest for cylindrical emitters, and the anti-clogging performance was greater for high-flow emitters. Through the stabilization of the uniformity coefficients (Cu and Us) and the reduction in their sensitivity to discharge ratio fluctuations (Dra), particularly in cases of minor clogging, micro-/nano-aeration also enhanced the uniformity of drip irrigation systems. According to the results, micro-/nano-aeration can improve the overall performance and stability of drip irrigation systems, decrease clogging, and extend the service life of emitters. [PERSON] et al. [46] presented carbon nanostructures and nano-zeolite-based electro-ceramic self-cleaning membranes, which were initially created through periodic electrolytic cleaning. The vacuum-filtered composite membranes exhibited good electrocatalytic performance for hydrogen evolution, high electrical conductivity, and hydrophilicity. Electrolysis produced hydrogen bubbles on the membrane surface during the filtration of sodium alginate and yeast, which successfully eliminated foulants and restored the membrane flux. The flux recovery for sodium alginate and yeast was 90% and 95%, respectively. In wastewater treatment, dye separation, and oil-water separation, where fouling and bacterial development are major concerns, the membranes also showed promising antibacterial qualities against both Gram-positive and Gram-negative bacteria. In this study, the concept of electrochemical self-cleaning, which was previously applicable only to polymeric membranes, was extended to ceramic-based membranes. [PERSON] et al. [47] examined the ways in which various bubble flows can be used to regulate and avoid organic fouling in ultrafiltration (UF) membranes. To investigate their impacts on fouling, both regular and oscillating bubble flows were created using a unique air-water vortex apparatus.