Some Issues by Algae on Water Supply in Tropical Country

水源水质原水浊度始终高于50NTU，雨季高于150NTU。原水平均浊度在80NTU左右，原水pH值在7.3~7.7之间。9月份原水电导率最低，为200亩S/厘米，2月份最高，为350亩S/厘米。河水中的藻类主要是环藻、直链藻属、硅藻、振荡藻、裸藻、小球藻、克氏杆菌、克氏杆菌等。和栅藻(Scenedesmus sp.)藻类细胞总数最大值平均为每100毫升数千个。藻类总数的70%以上是影响滤池堵塞的种类。因此，过滤器堵塞问题立即成为实际问题也就不足为奇了。藻类的可处理性对藻类的去除效率约为60%…平均较多，有时低于40%，尽管获得了较高的去除效率，对浊度的去除为98%。湖泊中的藻类在泰国面积18平方公里，平均水深1.8米的巴瑶湖，尽管藻类的存在不会同时发生堵塞，但至少所有由藻类引起的问题都将在未来发生。现在泰国人没有直接喝自来水的习惯。自来水中的气味、有毒物质、可溶性铝和THM问题可能与泰国人民和自来水厂无关。然而，混凝堵塞和滤砂堵塞与水处理工艺和系统密切相关，在泰国的河流和湖泊等水源中，观察到与藻类密切相关的物种种类。泰国的自来水厂将出现严重问题。泰国应继续进行藻类检测，这不仅是为了维护水源的水质，也是为了更好地运行净水工艺和系统。较少

Water Quality of Water SourceRaw water turbidity is always higher than 50 NTU and is over than 150 NTU in rainy season. Average turbidity of raw water is around 80 NTU.The pH values of raw water are 7.3 to 7.7. The conductivity of raw water in September is the lowest, 200 mu s/cm and is the highest, 350 mu s/cm in February. The average conductivity is 270 mu s/cm and the thick soluble matter is contained.Algae in RiverThe predominant species of the kind of algae in Chao Phya river as water source for metropolitan area are Cyclotella sp., Melosira sp., Diatom, Oscillatoria sp., Euglena sp., Chiorella sp., Clotieriopsis sp., Clasteriom sp. and Scenedesmus sp.. The total cell number of algae is thousands on average per 100 ml on maximum number. The species over the 70 % of total algae is the kind of affecting the filter clogging. It, therefore, comes as no surprise that the filter clogging problem becomes actual issue at once.Treatability of AlgaeThe removal rate for algae is around 60 % … More on average and is sometimes lower than 40 % in spite of getting high removal rate, 98 % for turbidity. It will be estimated to occur the some issues in distribution and service pipelines.Algae in LakesIn Payao lake, which has 18 km^2 in area and 1.8 m in average depth, in Thailand, at least all problems caused by algae will be occurred in the future though the existence of algae which affect the problem does not the occurrence of obstruction on same time. Now Thai people have no usage to drink tap water directly. Odour, toxic substances, soluble aluminium and THM problem in tap water may be no relation for Thai people and waterworks. However, coagulation blocking and sand filter clogging is deeply related to water treatment process and system.In the water source such as river and lake in Thailand, the kind of species closely related to some issues caused by algae are observed. It will be occurred serious problem on waterworks in Thailand. The examination of algae in Thailand should be continued for not only the maintenance of water quality of water source but also for better operation of water purification process and system. Less