In urban sewer design, the accomplishment of design intention is effected directly by the function of overflowing well, an important structure for combined sewer system with collector.
溢流井是城市截流式合流制排水系统的一个重要组成部分，它的成败直接影响着规划设计意图的实现。
3
Chelating agents combined with neutral oil may be used as effective collector for fine wolframite. The selectivity of flotation is much better than that of sodium oleate.