Method for Monitoring and Control of a Wastewater Process Stream

Abstract

The invention is directed towards methods, compositions, and apparatus for accurately detecting the presence and amounts of contaminants in wastewater. The method comprises the steps of adding to a volume of wastewater at least one tracer molecule, observing the tracer for indications of particular contaminants, conducting at least one second form of contamination detection, and interrelating the two measured properties to identify the specific composition of the contamination. Using a tracer molecule allows for the detection of otherwise hard to detect oils and grease. Use of the second method however compensates for tracer interfering contaminants and allows for more accurate readings. The invention includes feeding of functional chemicals in response to the detections and conducting the detections online and continuously.

1 .- 15 . (canceled) 
     
     
         16 . A method of detecting a nonpolar contaminant in a fluid having a polarity and a turbidity, comprising the steps of:
 a) providing a solvatochromatic tracer having a detectable change in fluorescence in the fluid that occurs in the presence of the nonpolar contaminant, wherein the detectable change in the fluorescence includes a shifting fluorescence emission wavelength that shifts depending on the polarity of the fluid;   b) introducing the solvatochromatic tracer into the fluid;   c) measuring a fluorescent property of the solvatochromatic tracer after the solvatochromatic tracer is introduced into the fluid;   d) providing a correction factor that corresponds to the degree to which the turbidity of the fluid scatters the fluorescence of the solvatochromatic tracer in the presence of the nonpolar contaminant and that takes into account the shifting fluorescent emission wavelength of the solvatochromatic tracer;   e) adjusting the detected fluorescence property according to the correction factor to provide a corrected fluorescent property; and   f) detecting the nonpolar contaminant in the fluid using the corrected fluorescent property.   
     
     
         17 . The method according to  claim 16  wherein detecting the nonpolar contaminant in the fluid comprises determining an amount of the nonpolar contaminant in the fluid. 
     
     
         18 . The method according to  claim 16  wherein detecting the nonpolar contaminant in the fluid comprises detecting a presence of the nonpolar contaminant in the fluid. 
     
     
         19 . The method according to  claim 16  further comprising measuring turbidity emitted fluorescence of the fluid before the solvatochromatic tracer is introduced into the fluid. 
     
     
         20 . The method according to  claim 19 , wherein step d) further comprises using the measured turbidity emitted fluorescence of the fluid to determine the correction factor. 
     
     
         21 . The method according to  claim 16  wherein the fluorescent property is fluorescence emission λ max . 
     
     
         22 . The method according to  claim 16  in which the fluid comprises water. 
     
     
         23 . The method of  claim 16  in which the fluid is wastewater. 
     
     
         24 . The method according to  claim 16  further comprising the step of adding a functional chemical to the fluid in response to detecting the contaminant, the functional chemical being suited to reduce, separate or inactivate the detected contaminant in the fluid. 
     
     
         25 . The method according to  claim 16  wherein the functional chemical comprises one or more selected from the group consisting of: a biocide, a dispersant, a flocculant, a surfactant, an emulsifier, a demulsifier, and a corrosion inhibitor. 
     
     
         26 . The method of  claim 16  wherein the solvatochromatic tracer is 9-(Diethylamino)-5H-benzo[a]phenoxazin-5-one. 
     
     
         27 . The method of claim  7 , wherein the nonpolar contaminant comprises an oil. 
     
     
         28 . The method of claim  7 , wherein the nonpolar contaminant comprises a grease. 
     
     
         29 . The method of claim  7 , wherein the nonpolar contaminant comprises a hydrocarbon liquid. 
     
     
         30 . A method of detecting a nonpolar contaminant in a fluid having a polarity and a turbidity, comprising the steps of:
 a) introducing a solvatochromatic tracer into the fluid, wherein the solvatochromatic tracer has a detectable change in fluorescence in the fluid that occurs in the presence of the nonpolar contaminant, wherein the detectable change in the fluorescence includes a shifting fluorescence emission wavelength that shifts depending on the polarity of the fluid and wherein the fluorescence has a detectable fluorescence property that depends on an amount of the specific non-polar contaminant in the fluid;   b) measuring a fluorescent property of the fluid after introducing the solvatochromatic tracer into the fluid;   c) correcting the measured fluorescence property taking into account the degree to which the turbidity of the fluid scatters the fluorescence of the solvatochromatic tracer in the presence of the nonpolar contaminant and that takes into account the shifting fluorescent emission wavelength of the solvatochromatic tracer that shifts depending on the polarity of the fluid; and   d) detecting the nonpolar contaminant in the fluid using the corrected fluorescent property.   
     
     
         31 . A method of detecting a nonpolar contaminant in a fluid having a polarity and a turbidity, comprising the steps of:
 a) introducing a solvatochromatic tracer into the fluid, wherein the solvatochromatic tracer has a detectable change in fluorescence that occurs in the presence of the nonpolar contaminant, wherein the detectable change in the fluorescence includes a spectral shift depending on the polarity of the fluid;   b) measuring a fluorescent property of the fluid after introducing the solvatochromatic tracer into the fluid;   c) correcting the measured fluorescence property to provide a corrected fluorescent property taking into account the degree to which the turbidity of the fluid scatters the fluorescence of the solvatochromatic tracer in the presence of the nonpolar contaminant and that takes into account the spectral shift; and   d) detecting the nonpolar contaminant in the fluid using the corrected fluorescent property.   
     
     
         32 . A method of detecting a nonpolar contaminant in wastewater having a polarity and a turbidity, comprising the steps of:
 a) adding a solvatochromatic tracer into a flowing fluid sample obtained from the wastewater, wherein the solvatochromatic tracer has a detectable change in fluorescence that occurs with changes in the amount of the nonpolar contaminant in the fluid sample, wherein the detectable change in the fluorescence includes a spectral shift that depends on the polarity of the fluid sample;   b) measuring the changing fluorescent property and the changing spectral shift of the flowing fluid sample that includes the added solvatochromatic tracer;   c) correcting the changing measured fluorescent property to provide a corrected fluorescent property that takes into account the degree to which the turbidity of the wastewater scatters the fluorescence of the solvatochromatic tracer in the presence of the nonpolar contaminant and that takes into account the changing spectral shift;   d) detecting the nonpolar contaminant in the wastewater using the corrected fluorescent property; and   e) in response to detecting the nonpolar contaminant in the wastewater, adding a functional chemical to the wastewater to treat the wastewater.   
     
     
         33 . The method according to  claim 32  wherein detecting the nonpolar contaminant in the fluid comprises determining an amount of the nonpolar contaminant in the fluid. 
     
     
         34 . The method according to  claim 32  wherein detecting the nonpolar contaminant in the fluid comprises detecting a presence of the nonpolar contaminant in the fluid. 
     
     
         35 . The method according to  claim 32  wherein the fluorescent property is fluorescence emission λ max . 
     
     
         36 . The method of  claim 32  wherein the functional chemical comprises one or more selected from the group consisting of: a biocide, a dispersant, a flocculant, a surfactant, an emulsifier, a demulsifier, and a corrosion inhibitor. 
     
     
         37 . The method of  claim 32  wherein the solvatochromatic tracer is 9-(Diethylamino)-5H-benzo[a]phenoxazin-5-one. 
     
     
         38 . The method of  claim 32 , further comprising repeating steps a) to d) after carrying out step e). 
     
     
         39 . The method of  claim 32 , wherein treating the wastewater with the functional chemical comprises reducing, separating or inactivating the nonpolar contaminant in the wastewater. 
     
     
         40 . The method of  claim 32 , wherein the nonpolar contaminant comprises an oil. 
     
     
         41 . The method of  claim 32 , further comprising the step of measuring the turbidity emitted fluorescence of the wastewater before the solvatochromatic tracer is added to the wastewater. 
     
     
         42 . The method of  claim 26 , wherein step c) comprises taking into account the measured turbidity emitted fluorescence of the wastewater. 
     
     
         43 . A method of detecting a specific nonpolar contaminant in a fluid having a polarity and a turbidity, comprising the steps of:
 a) introducing a solvatochromatic tracer into the fluid, wherein the solvatochromatic tracer has a detectable change in fluorescence in the fluid that occurs in the presence of the specific nonpolar contaminant, wherein the detectable change in the fluorescence includes a shifting fluorescence emission wavelength that shifts depending on an amount of the specific non-polar contaminant in the fluid;   b) measuring a fluorescent property of the fluid after introducing the solvatochromatic tracer into the fluid, wherein the measured fluorescent property is a known characteristic of the solvatochromatic tracer in the presence of the specific nonpolar contaminant;   c) correcting the measured fluorescence property taking into account the degree to which the turbidity of the fluid scatters the fluorescence of the solvatochromatic tracer in the presence of the specific nonpolar contaminant and that takes into account the shifting fluorescent emission wavelength of the solvatochromatic tracer that shifts depending on the polarity of the fluid; and   d) detecting the specific nonpolar contaminant in the fluid using the corrected fluorescent property.