tailieunhanh - ENVIRONMENTAL ENGINEER’S MATHEMATICS HANDBOOK - CHAPTER 16

Trong những ngày vinh quang của Dệt may Empire, dung môi, thuốc nhuộm được sử dụng trên các loại vải được đổ trực tiếp xuống sông, nhuộm các ngân hàng dưới đây ngã màu đỏ và màu xanh lá cây và màu vàng, theo các ngày trong tuần và kích thước của lô. Các ngân hàng dốc có nhẫn, giống như những người trong một thân cây, ngoại trừ những màu sắc cầu vồng, họ thu âm không phải là năm nhưng gia tăng và giảm của dòng sông. Ngay cả bây giờ, năm mươi năm sau, chỉ có cỏ. | Part V Math Concepts Wastewater Engineering 2005 by CRC Press LLC Chapter 16 Wastewater Calculations In the glory days of Empire Textiles the solvents and dyes used on the fabrics were dumped directly into the river staining the banks below the falls red and green and yellow according to the day of the week and the size of the batch. The sloping banks contained rings like those in a tree trunk except these were in rainbow colors they recorded not the years but the rise and fall of the river. Even now fifty years later only the hardiest weeds and scrub trees grew south of the pavement on Front Street and when the brush was periodically cleared surprising patches of fading chartreuse and magenta were revealed. Richard Russo Empire Falls 2001 introduction Standard wastewater treatment consists of a series of steps or unit processes tied together see Figure with the ultimate purpose of taking the raw sewage influent and turning it into an effluent that is often several times cleaner than the water in the outfalled water body. As we did for the water calculations presented in Chapter 15 we present math calculations related to wastewater at the operations level as well as the engineering level. Again our purpose in using this format is consistent with our intention to provide a single self-contained ready reference source. PRELIMINARY TREATMENT calculations The initial stage of treatment in the wastewater treatment process following collection and influent pumping is preliminary treatment. Process selection is normally based upon the expected characteristics of the influent flow. Raw influent entering the treatment plant may contain many kinds of materials trash preliminary treatment protects downstream plant equipment by removing these materials which could cause clogs jams or excessive wear in plant machinery. In addition the removal of various materials at the beginning of the treatment train saves valuable space within the treatment plant. Two of the .