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Frequently Asked Questions - Water Treatment
  • The sludge in my clarifier isn’t settling as well as it normally does. Is there anything I can do to improve the settling?
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    • There are several things that can be done, but first an attempt should be made to determine what might be causing the settling problem. The characteristics of the influent flow should be checked for anything unusual. This might help to determine if your plant is receiving a toxic or unusually high organic load. The internal plant treatment processes should also be checked for proper operation: Is there enough D.O. in the aeration tank? How much sludge is being retained in the system? The answer to improving the settling may be to change the treatment strategy slightly such as increasing or decreasing the return and wasting rates.
      The reason we conduct so many tests and record so much data is so that when “things” aren’t running right, we can go through this data and see what worked right in the past. Even though our job is to try to maintain that steady state of operations, there are always problems that arise beyond our control. Having access to this historical data can help you in dealing with these problems. While the corrective measures are being conducted, a settling agent can help to “tighten” up that blanket until the problem is corrected.
  • The sludge in my clarifier is floating to the surface in large clumps. I also see fine bubbles. Will bio-augmentation products help my system?
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    • Bio-augmentation products won’t help unless the problem is caused by a toxic chemical entering your system. As with all process disturbances, the operator must strive to determine the cause. A general overview of the influent flow should be checked for anything unusual such as a toxic chemical flow. The dissolved oxygen in the preceding aeration tank(s) should be checked with a calibrated D.O. meter. The D.O. level should be 1.5 to 4.0 mg/L. The sludge blanket level should be checked with a measuring devise such as a CorePRO. A general “rule of thumb” is that the blanket depth should be no more than 1/4 of the sidewall depth. In other words, a 10’ tank shouldn’t have more than a 2.5’ sludge blanket. Sludge that is rising in clumps with fine bubbles generally is indicative of denitrification. This is a process in which the microorganisms in the sludge goes without oxygen for too long and strips the oxygen off of the nitrate (NO3) in the sludge and forms nitrogen gas (N2). This gas is trapped in the sludge. If enough gas is released, the sludge sticks to the gas and floats to the surface. At this point, the only way to get the sludge to settle out is to break it up with a fire hose. This usually gets the sludge to settle back down. The sludge return rates should be increased to get the sludge back in the aeration tank where there is a viable source of oxygen.
  • Which gauges can I use for chlorine gas applications?
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    • We carry gauges with your choice of PVDF or Hastelloy-C gauge guards. Gauge guard chambers are filled with fluorolube instead of mineral oil to eliminate the potentially serious problems associated with mineral oil accidentally mixing with chlorine gas. Gauges with Monel internals are also available and these can be used in direct contact with chlorine gas.
  • I need to add polymer to one of my processes, what do you recommend?
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    • USABlueBook offers several means of delivering polymer. Several things need to be known before recommending a system. First of all, the type of process needs to be known. Different processes will require different amounts of polymer. Also, if the line or channel, where the injection point is, isn‘t providing enough mixing action on its own, a polymer blending system is an excellent choice.
      These systems have a chemical feed pump that feeds to a mixing chamber where it is mixed with dilution water. The dilution water also carries the polymer to its application point. We have many systems that can be built for your process, please contact us with the information below in order to properly size a polymer blending system for your process.
      Process flow
      Polymer dosage rate (ppm)
      Polymer type (dry, emulsion, or Mannich)
      Voltages available
      Water pressure available
      Floor space available
      Device used for clarification or filtration
  • I’m having trouble with my wastewater treatment process in our plant. Will the bio-augmentation products help my system and what is the guarantee?
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    • Bio-augmentation products are not magical elixirs, nor are they a miracle cure. These products generally contain the same bacteria that are found in a stable operating treatment system and can help a system to get back on track when recovering from an upset. They can also help an overloaded system handle a heavier-than-normal organic load.
      The first step in solving any problem at your plant is to determine the exact problem and what is causing it. Often times a system doesn‘t have enough available oxygen to sustain the amount of bacteria present. In this case, adding more bacteria (like a bio-augmentation product) is not the solution. In fact, this will only make matters worse since more bugs need more oxygen. The only alternatives are lightening the load of sludge in the system or increasing the oxygen levels by adding more aerators or blowers.
      If there is problem caused by a toxic condition, such as a chemical load entering the plant, this needs to be corrected. Some bio-augmentation products contain specific blends of bacteria that can survive in certain toxic conditions. But be aware - these are not “super bugs” and can die off just like any other bacteria. The best solution is finding the source of the toxic load and correcting it.
      If you’re experiencing any problem in your system, contact a USABlueBook technical support rep for assistance in choosing the correct bioaugmentation product.
  • I’m having trouble with algae in my pond. What do you recommend to get rid of it?
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    • There are many kinds of algae that form in ponds; floating, submerged, broad leaf and algae that form on the bottom of the pond. there are many chemical and non-chemical controls for algae. First, we have to figure out what type of algae that is there and what restrictions you have in introducing chemicals into the water.
      Many have chemicals like copper and other herbicides that can affect downstream processes and wildlife. We can recommend a chemical or a non-chemical approach to getting rid of the algae, depending on what type of algae is present and what restrictions you have in your discharge permit.
      Call our tech support with for a personalized approach to your algae problem.
  • How do I size a UV system for my application?
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    • First, you have to know the flow rate of the water you need to have sterilized. This is the maximum flow you are going to put through the unit. We also need to know if the water is well water, surface water or treated wastewater. This will affect the flow rates that will be able to go though the unit. When sizing for wastewater applications, the rul of thumb is 3X your flow rate for proper sizing.
      Most states require a transmittance level or UV energy of 20,000 microwatts per square centimeter. To allow for less than 100% transmittance, manufacturers and most states require 30,000 microwatts per square centimeter. This is what all of our units are rated at. This is accepted in all states except for New York where they recommend 40,000 microwatts per square centimeter.
      You can undersize our units by 25% to accommodate for the 40K rule.
  • What accessories are available for the UV Sterilizer units?
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    • There are many accessories that can be useful to assist in making your UV system more reliable. First is a UV monitor, this will measure the transmittance of the UV bulb and warn you when the light intensity is too low.
      Flow restrictors can be useful if there is a chance the water flow can exceed the rated flow of the unit. If the flow rate of the unit exceeds that of the manufactures specification, you might not have the correct transmittance level and not decontaminating the water.
      Time delay module is another accessory that can assist in a water system. This unit will turn off a valve if the electricity is cut to the unit and will not allow the water to flow until the unit has warmed up and the bulbs are up to full intensity.
      The last item is an elapsed time indicator. This can tell you how many hours are on your current bulbs and will remind you to change them before the unit fails.
  • I need to order UV Bulbs for my UV unit, what information do I need to have?
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    • There are many UV bulbs that differ for each manufacturer. You will need the following information to make sure you get the correct bulb for your unit:
      What is the Manufacturer and model of your UV unit?
      What is the date of the unit’s manufacture, if possible?
      What is the length of the UV Bulb? (not including the pins)
      Are there pins on one end or both?
      What is the pin configuration?
      What is the model number on the bulb?
      What is the power draw on the bulb?
      Is it a pre-heat or a rapid start bulb?
      With all or most of this information we can find the correct bulb for your unit.
  • I need replacement RO membrane(s) for my RO system, what do I need to get the correct one(s)?
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    • First, if you have a model number of the old membrane that would be enough, but if you do not we will need the following information:
      Overall length of the element
      Connection type, male or female
      Element Diameter
      Type of membrane, thin film or cellulose acetate
      Water operating temperature
      Presence of chlorine
      Maximum rated flow rate
      Outer wrap material
      System pressure
      This information should allow us to size the correct membrane for the application. Using a membrane not designed for the application will result on high reject rates and possibility for premature fouling.