Energy-saving technologies for reverse osmosis equipment to improve water yield and prevent and remove biofilms

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This post was last edited by slll611 on 2016-5-29 at 13:59. The dispersion and aggregation of colloids are determined by electrostatic forces (repulsive forces) and van der Waals forces (attractive forces)； Due to the charge on the surface of the dispersed particles, which attracts the surrounding counterions, these counterions are distributed at the interface between the two phases, forming a diffuse double layer. According to the Stern double-layer theory, the double layer can be divided into two parts, namely the Stern layer and the diffusion layer. The Stern layer is defined as a planar layer composed of charge centers of ions (IHP or OHP) adsorbed on the electrode surface; the potential at a point in the fluid relatively far from the interface with respect to this planar layer is called the Stern potential. The interface that forms when the stationary layer (which includes the Stern layer and the part of the diffusion layer within the slipping plane) moves relative to the dispersion medium in the diffusion layer is the slipping plane. The potential at a certain point in the fluid away from this interface is known as the Zeta potential or electrostatic potential (ζ-potential). The DLVO theory was proposed independently by Derjguin and Landau in 1941, and by Verwey and Overbeek in 1948. Therefore, the theory is usually named after the initial letters of the four people's names. In the DLVO theory, they believe that whether a sol can exist stably under certain conditions depends on the potential energy of the interactions between the colloidal particles. The total potential energy equals the sum of the van der Waals attractive potential energy and the electrostatic repulsive potential energy caused by the double layer. Both types of potential energy are functions of the distance between colloidal particles; the attractive potential energy is inversely proportional to the sixth power of the distance, whereas the electrostatic repulsive potential energy decreases exponentially with distance. The forces acting between these two types of potential energy are van der Waals attraction and electrostatic repulsion. These two opposing forces determine the stability of the colloid. The Zeat Rod utilizes applied electrochemical technology: an insulating electrode, namely the Rod electrode, is inserted into pipelines or tanks to act on the colloids in the water. A power supply converts 90-240V AC electricity into 35KV high-voltage DC electricity, and the high-voltage discharge generates a capacitance on the surface of the electrode rod (i.e., zeta potential), thereby increasing the surface charge density of the colloids and enhancing the electrostatic repulsion between particles, allowing them to disperse and form a stable suspension. It also prevents particles from adhering to the surfaces of containers and pipelines, stops the formation of structures and gel clumps, and inhibits the growth of bacterial microorganisms. The charging effect also possesses a very strong ability to remove or uniformize biofilms. (Not a fungicide). In RO reverse osmosis systems, it can increase the water output of such systems, extend the lifespan of the membranes, and improve the overall energy efficiency of the devices. It can also be applied in heat exchangers, cooling towers, and washing towers. It is currently being used in the RO systems of Kunshan Helin Optoelectronics High-Tech Co., Ltd., FuKui Precision Components (Shenzhen) Co., Ltd., Changchun Chemical (Changshu) Co., Ltd., Changchun Chemical (Miaoli) Co., Ltd., Foxconn Group’s Fuyong plant, Songgang plant, Tianren plant, Jiugushan Food Company, PepsiCo, etc., with remarkable results. The increased water output rate due to reverse osmosis can rise by 3–10%, and after multiple cleanings, it exceeds the originally designed water output rate. At the same time, the dosage of chemicals can be reduced by about 30%, and the addition of scale inhibitors can even be completely stopped. At the same time, by extending the cleaning time and increasing the lifespan of the reverse osmosis membrane, energy consumption is correspondingly reduced.