臭氧不臭 淨水高手
水是生活中不可或缺的物質，小朋友有想過，怎樣確保食水是乾淨及安全飲用嗎？食水從水龍頭流出來之前，先要經過澄清、過濾及消毒，當中常見的消毒方法是使用氧氣。近年有社會企業將臭氧消毒技術應用在學校添水機中，一同來了解臭氧如何達致消毒功效吧！
臭氧層的臭氧原來具有強力的消毒能力，聰明的人類，早在百多年前就發現臭氧的厲害，並且把臭氧廣泛應用在生活和醫療方面，最近有小學的添水機亦應用到臭氧技術呢。
臭氧臭嗎？
臭氧知多點 臭氧是甚麼？
臭氧對地球十分重要，大氣層中的「臭氧層」，猶如一道天然屏障，阻擋對人體有害的紫外線。臭氧也是非常強的氧化劑和消毒劑，能夠有效抗菌、除味及除去有毒物質。它可以破壞細菌和病毒的結構，令細菌無法生存。
臭氧有什麼厲害？
臭氧是常見的消毒劑，香港水務署為食水進行消毒步驟時，會加入臭氧或氯氣。那麼臭氧和氯氣相比，那一個比較「厲害」？臭氧的殺菌力是氯氣的3000倍，而且臭氧反應完畢之後，會立即還原成氧氣，不會產生殘留物，不用擔心造成二次污染。氯的消毒功效較差，產生異味，也會於水中有機物形成致癌物質「三鹵甲烷」，不過因其價格較臭氧底，仍有不少國家選用氯來為食水消毒。
臭氧消毒 應用廣泛
臭氧在180年前被人發現，自此人類得到了強效消毒劑，應用在生活上各個層面。
醫療 – 臭氧消毒常用於醫療領域，如病房及手術室的空氣消毒。牙醫亦常常使用臭氧水給病人漱口，達致消毒和除臭的功效。
空氣淨化 – 氣態的臭氧能夠迅速彌漫都整個空間進行滅菌，適合用於空氣淨化。不過人體吸入氧氣可引致口亁、咳嗽，並會刺激鼻孔及咽喉，使用高濃度臭氧進行空氣淨化時，應在空置房間進行。
水質 – 臭氧可以淨化水質，例如是泳池水及飲用水。見淨化的臭氧水亦可用作清洗物品及食材，例如去除蔬菜和水果上的殘留農藥，或替肉類、魚類、貝殼類食物殺菌。
智能添水機 斟水救地球
社會企業「城泉」近年推出智能添水機「Well井」，應用臭氧消毒技術，替飲用水進行深層清潔。現時有超過三十所小學使用智能添水機，其中一所為英華小學。英華小學常識科科主任葉挺堅指，新水機放在學校約四個月，學生感覺好奇，爭相使用，放學時甚至出現人龍。這部令同學躍躍欲試的添水機有何特別？一同來看看吧！
大數據管理 – 適時提醒公司更換濾芯，亦會計算出水量，於屏幕顯示節省了多少膠樽，鼓勵學生自備水樽斟水。
出水位 – 出水位置隱蔽，避免瓶口觸碰出水口，減低交叉感染的機會。
腳踏 – 踩腳踏出水，不需要用手長按開關。
香港每日有超過五百萬個膠樽落入堆填區，全世界每一分鐘消耗一百萬膠樽。我們可以為地球出一分力，減少購買樽裝飲品，走塑救地球！
同學有話兒
「我覺得這部水機不錯，因為它是一部智能水機，可以避免接觸出水後，感覺更加安全。」黃昊（小五）
「我有自備水樽的習慣，每日會斟三次水。這部水機好好用，可以用腳踏出水，不用長按按扭出水。」林柏舜（小四)
「添水機的水沒有怪味，溫度清涼，適合夏天飲用。」周浩鑨 （小五）
The ozone is a master in water purification
Water is essential to life. But have you, students, ever thought about how to ensure that drinking water is clean and safe to drink? Before the water flows out from the faucet, it must be filtered and disinfected. One common disinfection method is to use ozone. In recent years, ozone disinfection technology has been applied to school water dispensers by one social enterprise. Let’s learn how ozone can achieve disinfection effect!
Ozone in the ozone layer has strong disinfection ability. Humans have discovered the power of ozone as early as more than a hundred years ago. It has then been widely used in life and medical treatment. Recently, the water dispensers in elementary schools has also adopted the ozone disinfection technology.
Does Ozone smell?
(Note: The literal Chinese meaning of “Ozone” = “smelly oxygen” )
In fact, ozone doesn’t have a bad odour. It actually has a refreshing green smell. After the thunderstorm, the air is always filled with a refreshing green smell, that is the odour of ozone.
The high-voltage electricity released from the lightning separates the oxygen in the air into oxygen ions, and when the oxygen ions collide with the oxygen molecules to form oxygen, ozone concentration in the air will increase. A “refreshing green smell” will thereby be produced. If ozone doesn’t smell, where does its name come from? Ozone was discovered by a Swiss chemist in 1840. When he conducted a water electrolysis experiment at a university, he smelled a unique scent in the laboratory. Inspired by the Greek word “ozein” (meaning “to smell”), he named it “ozone”.
Getting to know more about ozone! What is ozone?
Ozone is very important to the earth. The “ozone layer” in the atmosphere acts as a natural barrier, blocking out ultraviolet rays which are harmful to human body. Ozone is also a very strong oxidant and disinfectant, which can help resist bacteria, deodorize and remove toxic substances. It can destroy the structure of bacteria and viruses, making them unable to survive.
What’s so special about ozone?
Ozone is a common disinfectant. The Hong Kong Water Supplies Department adds ozone or chlorine during the disinfection procedures for drinking water. Between ozone and chlorine, which one is more powerful? The sterilizing ability of ozone is 3,000 times of chlorine. Moreover, ozone will turn into oxygen immediately after its chemical reaction is over, generating no residue. Therefore, there is no need to worry about causing secondary pollution. Whereas chlorine has a weaker disinfection effect. It produces odour, and also forms a carcinogen called “trihalomethane” in organic matter in the water. However, because of its cheaper price, many countries still choose to use chlorine for disinfecting drinking water.
The widely used ozone disinfection technology
Ozone was discovered 180 years ago, and since then humans have obtained a potent disinfectant to be applied at all levels of life.
Medical field – Ozone disinfection is commonly used in the medical field, such as air disinfection in wards and operating rooms. Dentists also often offer ozonated water for their patient to rinse their mouths for disinfection and deodorization purposes.
Air purification – Gaseous ozone can quickly diffuse through the entire space for sterilization, which is suitable for air purification. However, inhaling ozone can lead to mouth dryness and coughing, irritating the nose and the throat. Therefore, air purification using highly concentrated ozone should be done in an empty room.
Water quality – Ozone can be used to purify water such as pool water and drinking water. Ozonated water left after purification can also be used to clean objects and food, for example to remove pesticide residue on vegetables and fruit, or to kill the bacteria in meat, fish and shellfish.
The smart water dispenser saves the earth from plastic bottled water by encouraging refilling
The smart water station “Well井”, launched by a social enterprises called “Urban Spring”, adopted ozone disinfection technology for deep cleansing of drinking water. There are currently more than 30 primary schools using smart water station, one of which is Ying Wa Primary School. Mr. Ip, the General Studies Panel Head of the school, said that Well井smart water station has been installed in the school for around 4 months. There is often a long queue at Well井because the students are curious and eager to use it.
What’s so special about this water station that makes students eager to try? Let’s take a look！
Big data management – This is to remind the company to replace the filter timely. The bottle saved number is displayed on the screen to encourage students to bring their own water bottles for refills.
Nozzle – The hidden nozzle can prevent any contact with user’s bottle, minimising risk of contamination.
Foot pedal – Refilling by using the foot pedal means that it is no longer necessary to press and hold the button by hand.
Over 5 million plastic bottles end-up in the landfill everyday in Hong Kong. 1 million plastic bottles are consumed every minute across the world. All of us can contribute to protecting the Earth. Let’s buy less bottled drinks, and save the planet by using less plastics!
Words from students
“This water dispenser is pretty good because it is smart. It feels safer because the nozzle is hidden to avoid any contact with it. ” Ho Wong (P5 student)
“I have a habit of bringing my own bottle and refill my bottle three times a day. This water dispenser is very useful because I can step on the foot pedal instead of pressing the button for refilling. ” Pak-Shun Lam (P4 student)
“Water from the water dispenser is cool and doesn’t smell, which is suitable for drinking in summer.” Ho-Lung Chau (P5 student)