Trong chà ẩm ướt, một chất lỏng phun, thường là nước, được sử dụng để nắm bắt bụi hạt hoặc để tăng kích thước của hạt nhân ngưng tụ. Tăng kích thước tạo điều kiện tách của hạt từ khí nhà cung cấp dịch vụ. Ướt chà hiệu quả có thể loại bỏ các hạt mịn trong khoảng từ 0,1 micromet đến 20 micromet. Các hạt có thể bị bắt đầu tiên của chất lỏng, hoặc đầu tiên về cơ cấu chà sàn, và sau đó rửa sạch bằng chất lỏng. Bởi vì hầu hết các máy lọc thông thường. | 22 Design and Application of Wet Scrubbers INTRODUCTION In wet scrubbing an atomized liquid usually water is used to capture particulate dust or to increase the size of aerosols. Increasing size facilitates separation of the particulate from the carrier gas. Wet scrubbing can effectively remove fine particles in the range from pm to 20 pm. The particles may be caught first by the liquid or first on the scrubber structure and then washed off by the liquid. Because most conventional scrubbers depend upon some form of inertial collection of particulates as the primary mechanism of capture scrubbers when used in a conventional way have a limited capacity for controlling fine particulates. Unfortunately inertial forces become insignificantly small as particle size decreases and collection efficiency decreases rapidly as particle size decreases. As a result it becomes necessary to greatly increase the energy input to a wet scrubber to significantly improve the efficiency of collection of fine particles. Even with great energy inputs wet scrubber collection efficiencies are not high with particles less than pm in size. Wet scrubbers have some unique characteristics useful for fine particulate control. Since the captured particles are trapped in a liquid re-entrainment is avoided and the trapped particles can be easily removed from the collection device. Wet scrubbers can be used with high-temperature gases where cooling of the gas is acceptable and also with potentially explosive gases. Scrubbers are relatively inexpensive when removal of fine particulates is not critical. Also scrubbers are operated more easily than other sophisticated types of particulate removal equipment. Wet scrubbers can be employed for the dual purpose of absorbing gaseous pollutants while removing particulates. Both horizontal and vertical spray towers have been used extensively to control gaseous emissions when particulates are present. Cyclonic spray towers may provide slightly .
