南水北調中線工程藻水分離技術研究

王文 苗淳洋 李昊

摘 要：南水北調中線工程干渠藻類滋生，從干渠內攔截或者從邊坡抽吸的藻水混合物數量很大，受場地制約和環保要求必須對藻水混合物進行藻水分離。利用振動篩的工作原理，由激振系統產生的激振力帶動篩箱振動，通過高密度篩網實現藻水分離，分離后的水可直接流回干渠或灌溉干渠兩側綠化帶，分離后的藻漿進行收集外運。針對藻類濃度的變化，可以改變藻水分離振動裝置激振系統的頻率和振幅，實現可調頻、可調幅的振動分離功能。該裝置可以與干渠節制閘自動化攔藻設備或渠道邊坡除藻車配合使用，實現攔藻、除藻和藻水分離同步進行。試驗結果表明，該裝置性能穩定、運行安全可靠，藻水分離效果良好，機械自動化水平高，可以為南水北調中線工程環境維護節約大量人力、物力和財力。

關鍵詞：藻水分離;篩網;南水北調中線工程

中圖分類號：TV213; TV53 ? 文獻標志碼：A

doi：10.3969/j.issn.1000-1379.2020.07.018

Abstract：The algae grow rapidly in the main canal of the Mid-Route of South-to-North Water Diversion Project. There are too much mixtures of algae and water removed from the main canal or the side slope， and the algae separation is necessary for the limited space and the environmental requirements. The working principle of the vibrating screen was used， and the vibration of the screen box was induced by the excitation system of the algae separation equipment， and the algae were separated by the high density screen. The water was used to irrigate the greenbelt along both sides of the main canal or returned to the main canal after filtration， and the algae were collected for transportation. The frequency and amplitude of the excitation system could be changed according to the different concentration of the algae water， therefore the algae vibrational separation equipment was both frequency-adjustable and amplitude-adjustable. This equipment could work together with the automatic mechanical algae removal equipment of the main canal sluice or the algae removal truck of the side slope， then the algae could be separated as soon as they were removed from the canal or the side slope. The results show that this equipment has the advantages of steady performance， safe and reliable operation， and good effects of the algae separation and highly mechanized. This equipment can save a lot of manpower， material resources and financial resources for environmental maintenance of the Mid-Route of South-to-North Water Diversion Project.

Key words： algae separation; screen; Mid-Route of South-to-North Water Diversion Project

隨著人類社會工業化進程的加快，工農業生產以及人們日常生活排污加速了內陸湖泊、水庫等緩流水體的富營養化。水體富營養化導致藻類滋生，大量繁殖的藻類呈膠質狀覆蓋在河面上或懸浮在水中，使水體中溶解氧含量快速減少，破壞水生態系統平衡，藻類還會釋放毒性較強的藻毒素，影響用水者的身體健康[1]。南水北調中線工程作為一項重大的民生工程，有效緩解了華北地區的用水壓力，但是每年6—11月干渠一些區段藻類滋生，水面一定深度下邊坡上附著大量藻類，嚴重影響水體質量。目前南水北調中線干渠主要采用機械或人工打撈的除藻方式[2]，例如在干渠節制閘門處設置自動化過濾設備攔截藻類，或使用渠道邊坡除藻車沖洗和抽吸岸坡上附著的藻類。但是攔截或抽吸上來的藻水混合物數量很大，沒有足夠大的場地或容器進行存放和處理，外運處理經濟上不可行[3]，采取渠岸自然放置處理，未能有效處置的藻類會腐爛發臭，對環境造成二次污染[4]。因此，在前期藻類清除和攔截的基礎上，如何對收集的藻類進行脫水分離并有效利用，是當前亟待解決的技術問題。