[News](/in/en/news/) / [Cover balls](/in/en/news/?category=cover-balls) 11 August 2023 # Odor control and evaporation reduction in wastewater treatment However, this odor is not caused by the process itself, but by the evaporation of water and some of the substances contained within, which are released into the air, where we can then inhale and smell them. Closed-system wastewater treatment is usually not a realistic option because of the large volumes and considerable extra costs involved. Thus, the easiest way to reduce unpleasant odors is to reduce evaporation, which can be practically achieved by covering the surface of the water. However, since active processes continue to be carried out in the clarifiers and basins – adding and removing water, continuous mixing, introducing and filtering out various substances, etc. – a contiguous film cover is not a viable option. Firstly, film covers are not very resistant to long-term outdoor use, as they can easily be damaged by storms or strong winds. Secondly, they can hinder the movement of mixing arms, or cause problems during the aeration of wastewater. Cover balls offer a solution to this problem, as they can easily withstand UV radiation and stormy winds, as well as all the chemical effects occurring during the treatment process. Floating on the surface, these balls do not interfere with the aforementioned technological and chemical processes, while still covering 91% of the surface, thereby reducing evaporation and thus the formation of odors. The balls follow changes in water level, and are also excellent thermal insulators. The latter is important because the biological processes taking place during clarification require a specific temperature range, which the balls can also help maintain: they prevent the risk of freezing in winter, and protect against overheating in summer. ### Related Product [ Cover balls The Euro-Matic outdoor cover ball is the best choice for airports, mines, sewage treatment plants and livestock farms, as well as for covering reservoirs. Learn more ](/in/en/products/cover-balls/)### What is a cover ball? The cover ball is a hollow high quality plastic ball that can be used to create a continuous cover layer on the surface of liquids. Depending on the amount of balls placed on a given surface, they can cover up 91% of the surface in a regular shape, self-arranging next to each other. This cover layer separates and isolates the open surface of the liquid from its surroundings, i.e. it significantly reduces the effect of the liquid on the environment and vice versa. In English, several names are used for these balls, often referred to as ‘shade ball’, ‘cover ball’, ‘armor ball’, ‘barrier ball’, or ‘bird ball’. We, as a proud European Manufacturer, call them cover ball and Bird Ball™. [VIEW OUR PRODUCTS](https://euro-matic.eu/in/en/shop/?category=cover-balls) ### How does it work? What can it be used for? The cover balls have countless benefits, so it can be used in many diverse areas. Those advantages usually help our partners to achieve their goals for cost-saving, more efficient water management, safer work environment, environment and nature protection. Thus, the Bird Ball™ is an excellent solution for reducing evaporation, preserving water quality, preventing algae formation, keeping birds away, camouflaging the water surface, thermal insulation, reducing heating costs, reducing the release of toxic gases and vapors, reducing unpleasant odors, covering hazardous materials and many more, where cost savings or other beneficial effects can be achieved as a result of use. ### ### Types **Bird Ball™****Water-filled Bird Ball™****Self-Filling Ball®** Diameter100 mm100 mm100 mm Weight40 g240 g40 g MaterialHDPEHDPEHDPE UV resistanceYesYesYesColorBlackBlackClear/black Warranty10 years10 years10 years Wind resistanceUp to 80 km/hUp to 150 km/hUp to 150 km/h PackagingBig-bag, cardboard or in bulkBig-bag or in bulkBig-bag, cardboard or in bulk Quantity116 balls/m2116 balls/m2116 balls/m2 [SEND ME AN OFFER](https://euro-matic.eu/in/en/get-a-quote/) ## Shop Cover balls [See all products](/in/en/shop/?category=cover-balls) [Fish Ball 38/50 mm 8,3 g clear € 120,00 / 1000 pcs ](/in/en/shop/fish-ball-38-50-mm-8-3-g-clear/) [Fish Ball 38/50 mm 8,3 g transparent blue € 126,00 / 1000 pcs ](/in/en/shop/fish-ball-38-50-mm-8-3-g-transparent-blue/) [Bird ball™ 100 mm 40 g black ](/in/en/shop/bird-ball-TM-100-mm-40-g-black/) [Water-filled Bird ball™ 100 mm 240 g black ](/in/en/shop/water-filled-bird-ball-TM-100-mm-240-g-black/) ### Related References [ Water-filled Bird Ball™ at Brussels Airport Cover balls ](/in/en/references/offloading-bird-balls-at-brussels-airport/) [ Covering water reservoirs with outdoor cover balls Cover balls ](/in/en/references/covering-water-reservoirs-with-outdoor-cover-balls/) [ At Heathrow Airport, since 2004 Cover balls ](/in/en/references/at-heathrow-airport-since-2004-/) [ Bird Ball™ balls in sewage treatment plants Cover balls ](/in/en/references/bird-ball-balls-in-sewage-treatment-plants/) [ Bird Balls™ are also used at Klagenfurt Airport Cover balls ](/in/en/references/bird-balls-are-also-used-at-klagenfurt-airport/) [](/) [News](/in/en/news/) [About us](/in/en/about-us/) [Products](/in/en/products/) [Contact](/in/en/contact/) [References](/in/en/references/) [Shop](/in/en/shop/) If you would like to buy a bigger amount, please ask for [an individual offer](/hu/hu/arajanlat-keres/)! 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