Spray tower exists as a treatment equipment for environmental waste gas treatment. According to the working principle, it is divided into circulating water spray tower, alkali spray tower, and acid spray tower (also known as pickling tower). Based on the tower body material, these are classified into FRP spray tower, PP spray tower, and stainless steel spray tower. Choosing a reasonable spray material and process depends on the specific properties of the waste gas.

Counterflow Spray Tower Design

In counterflow spray towers, the inlet gas stream usually enters from the bottom and moves upward, while the liquid is sprayed downward from multiple levels. This technology serves as an efficient wet scrubber for air pollution control. Counterflow exposure ensures that outlet gas with the lowest pollutant concentration meets the freshest scrubbing liquid. Many nozzles are placed at different heights to maximize fine droplets hitting pollutant particles, providing a large gas absorption surface area.

Droplets must be large enough (usually 500-1000 microns) to avoid being carried out in the outlet gas stream. Gas velocity is typically kept low, from 0.3 to 1.2 m/s (1-4 ft/s), to prevent excess droplet carry-over. Consequently, spray towers are often larger than other scrubbers handling similar gas flow rates.

Picture 1: Cross flow spray tower

In co-current spray towers, the inlet gas and liquid flow in the same direction, allowing for higher gas velocities and smaller vessel sizes. In cross-flow (horizontal) spray scrubbers, gas flows horizontally through multiple spray sections while liquid falls vertically. Cleanest liquid is typically used in the final spray stage to ensure optimal purification.

• The equipment occupies a small area and is easy to install.
• Low water and power consumption indicators.
• Corrosion-resistant, non-wear, and offers a long service life.
• Reliable operation with simple and convenient maintenance requirements.

The packing layer serves as a mass transfer device between gas and liquid phases. A support plate at the bottom holds random packing, while a pressure plate at the top prevents displacement from airflow. Liquid is distributed from the top and flows down the packing surface while gas enters from the bottom. To prevent "wall flow" and maintain efficiency, packing layers are often divided into sections with redistribution devices.

Picture 2: Flow chart

Picture 3: Packed bed spray tower

Picture 4: Venturi scrubber

Picture 5: Cyclone plate tower

Picture 6: Desulfurization tower

• Chemical Manufacturing: Controlling emissions from acid production or paint manufacturing.
• Power Generation: Removal of sulfur dioxide (SO2) from coal-fired power plant flue gases.
• Metallurgical Industries: Controlling emissions from steel and aluminum furnaces.
• Waste Incineration: Purifying exhaust gases from municipal and hazardous waste incinerators.
• Food Processing: Managing odorous gases and particulate matter for a hygienic environment.

Spray towers are indispensable tools in the fight against air pollution, offering a versatile and efficient solution for various industrial applications. By leveraging advanced scrubbing capabilities, these systems contribute significantly to environmental protection and public health, helping industries operate within strict regulatory frameworks.