tailieunhanh - INTRODUCTION TO URBAN WATER DISTRIBUTION - CHAPTER 2

Vận chuyển nước NGỮ trong một hệ thống cung cấp nước phụ thuộc vào tỷ lệ sản xuất, tiêu thụ, cung cấp và rò rỉ (hình ). Nước sản xuất sản xuất nước (Qwp) diễn ra tại các cơ sở xử lý nước. Nó thường có một tỷ lệ cố định mà phụ thuộc vào khả năng thanh lọc của bản cài đặt điều trị. Nước được xử lý kết thúc trong một hồ chứa nước sạch từ nơi nó được cung cấp cho hệ thống (hồ chứa A trong hình ). Nước cung cấp (Qwd) bắt đầu từ hồ. | CHAPTER 2 Water Demand Water production Water delivery TERMINOLOGY Water conveyance in a water supply system depends on the rates of production delivery consumption and leakage Figure . Water production Qwp takes place at water treatment facilities. It normally has a constant rate that depends on the purification capacity of the treatment installation. The treated water ends up in a clear water reservoir from where it is supplied to the system Reservoir A in Figure . Water delivery Qwd starts from the clear water reservoir of the treatment plant. Supplied directly to the distribution network the generated flow will match certain demand patterns. When the distribution area is located far away from the treatment plant the water is likely to be transported to another reservoir B in Figure that is usually constructed at the beginning of the distribution network. In principle this delivery is done at the same constant flow rate that is equal to the water production. Figure . Flows in water supply systems. Production Qwp Delivery Qwd Ị Demand Qd Consumption Qwc Leakage Qwi 2006 Taylor Francis Group London UK 22 Introduction to Urban Water Distribution Water consumption Water consumption Qwc is the quantity directly utilised by the consumers. This generates variable flows in the distribution network caused by many factors users needs climate source capacity etc. Water leakage Water leakage Qwl is the amount of water physically lost from the system. The generated flow rate is in this case more or less constant and depends on overall conditions in the system. Water demand In theory the term water demand Qd coincides with water consumption. In practice however the demand is often monitored at supply points where the measurements include leakage as well as the quantities used to refill the balancing tanks that may exist in the system. In order to avoid false conclusions a clear distinction between the measurements at various points of the system should .