Addition of alkaline materials to biotrickling filter or bio-filter make-up water

Abstract

A system for removing undesirable compounds from contaminated air includes a biofilter having an alkaline material introduction system and a fuzzy-logic based controller. A contaminant, such as hydrogen sulfide, is removed from contaminated air by passing the contaminated air through the biofilter.

What is claimed is: 
     
         1 - 22 . (canceled) 
     
     
         23 . A method of reducing water consumption of a biotrickling filter, the method comprising:
 adding a pH adjustment system to the biotrickling filter, the pH adjustment system configured to:   introduce an alkaline material from a source of alkaline material into the biotrickling filter;   measure a pH of a liquid in the biotrickling filter; and   control a rate of introduction of the alkaline material and a rate of introduction of water into the biotrickling filter to be sufficient to maintain the pH of the liquid within a range conducive to maintain a population of hydrogen sulfide oxidizing bacteria in a media bed of the biotrickling filter and to prevent clogging of the media bed.   
     
     
         24 . The method of  claim 23 , comprising controlling the rate of introduction of the alkaline material and the rate of introduction of the water with a fuzzy logic controller utilizing the pH as an input parameter of a fuzzy logic control algorithm. 
     
     
         25 . The method of  claim 23 , wherein reducing the water consumption of the biotrickling filter includes reducing the water consumption of the biotrickling filter by to at least about 50%. 
     
     
         26 . The method of  claim 25 , wherein reducing the water consumption of biotrickling filter includes reducing the water consumption of the biotrickling filter by at least about 99%. 
     
     
         27 . A wastewater treatment system comprising:
 a basin including a wastewater inlet fluidly connected to a source of wastewater;   a process gas outlet configured to output sulfur-containing process gas generated by the wastewater from the basin;   a source of alkaline material; and   a biotrickling filter comprising:   a vessel;   a contaminated air inlet providing fluid communication between an internal volume of the vessel and the process gas outlet;   a treated air outlet in fluid communication with the internal volume of the vessel;   a media bed disposed within the vessel and in fluid communication between the contaminated air inlet and the treated air outlet;   biofiltering media disposed in the media bed, the biofiltering media configured to support growth and maintenance of a population of hydrogen sulfide oxidizing bacteria on the biofiltering media;   a water introduction system configured to introduce water from a source of water into the vessel; and   an alkaline material introduction system configured to introduce an alkaline material from the source of alkaline material into the vessel.   
     
     
         28 . The system of  claim 27 , further comprising a sensor configured to measure a pH of a liquid within the vessel and to provide an indication of the pH to a controller configured to regulate a rate of introduction of the water and a rate of introduction of the alkaline material into the vessel. 
     
     
         29 . The system of  claim 28 , wherein the controller is configured to regulate the rate of introduction of the water and the rate of introduction of the alkaline material into the vessel based on an output of a fuzzy logic algorithm utilizing the indication of the pH as an input parameter.