Abstract: A waste water processing system includes an upflow contacting column having a flue gas input for receiving flue gas having a temperature of at least 500 degrees F., a waste water input, and a flue gas output. The waste water input is coupled to a fluid injector, e.g., atomizing nozzles, positioned in the throat of a Venturi portion of the upflow contacting column or in a sidewall of the throat of the Venturi portion of the upflow contacting column. The flue gas in the upflow contacting column has a high velocity, e.g., a gas velocity exceeding 65 fps in the throat of the Venturi portion of the upflow contacting column at a position where the fluid injector is located. Drying additives such as recycled ash, lime, and/or cement may be, and sometimes are, input into the upflow contacting column downstream of the waste water input.

Abstract: A waste water processing system includes an upflow contacting column having a flue gas input for receiving flue gas having a temperature of at least 500 degrees F., a waste water input, and a flue gas output. The waste water input is coupled to a fluid injector, e.g., atomizing nozzles, positioned in the throat of a Venturi portion of the upflow contacting column or in a sidewall of the throat of the Venturi portion of the upflow contacting column. The flue gas in the upflow contacting column has a high velocity, e.g., a gas velocity exceeding 65 fps in the throat of the Venturi portion of the upflow contacting column at a position where the fluid injector is located. Drying additives such as recycled ash, lime, and/or cement may be, and sometimes are, input into the upflow contacting column downstream of the waste water input.

Abstract: A waste water processing system includes an upflow contacting column having a flue gas input for receiving flue gas having a temperature of at least 500 degrees F., a waste water input, and a flue gas output. The waste water input is coupled to a fluid injector, e.g., atomizing nozzles, positioned in the throat of a Venturi portion of the upflow contacting column or in a sidewall of the throat of the Venturi portion of the upflow contacting column. The flue gas in the upflow contacting column has a high velocity, e.g., a gas velocity exceeding 65 fps in the throat of the Venturi portion of the upflow contacting column at a position where the fluid injector is located. Drying additives such as recycled ash, lime, and/or cement may be, and sometimes are, input into the upflow contacting column downstream of the waste water input.

Abstract: A waste water processing system includes an upflow contacting column having a flue gas input for receiving flue gas having a temperature of at least 500 degrees F., a waste water input, and a flue gas output. The waste water input is coupled to a fluid injector, e.g., atomizing nozzles, positioned in the throat of a Venturi portion of the upflow contacting column or in a sidewall of the throat of the Venturi portion of the upflow contacting column. The flue gas in the upflow contacting column has a high velocity, e.g., a gas velocity exceeding 65 fps in the throat of the Venturi portion of the upflow contacting column at a position where the fluid injector is located. Drying additives such as recycled ash, lime, and/or cement may be, and sometimes are, input into the upflow contacting column downstream of the waste water input.

Abstract: Flue gas processing is described. A circulating dry flue gas desulfurization (DFGD) scrubber is positioned upstream of a wet flue gas desulfurization (WFGD) scrubber. Flue gas temperature and humidity is controlled. Reagent use is monitored and controlled. The DFGD scrubber is controlled without concern for sulfur dioxide absorption and thus reagent utilization is controlled based on the goal of removing one or more of: sulfur trioxide and/or other acid gases. In some embodiments the circulating DFGD scrubber removes the majority of sulfur trioxide, HCL, and/or HF from the flue gas stream supplied to the DFGD scrubber. The DFGD scrubber is followed by the WFGD scrubber that removes sulfur dioxide and mercury, to achieve a high degree of pollutant removal at a low operating cost as compared to some other systems. WFGD scrubber liquid waste is sent to the circulating DFGD scrubber and used for temperature and/or humidity control purposes.