pH values adjustment

How to adjust pH values when it's increase or decrease in wastewater bodies. 

Taxonomy

• Industrial Wastewater Treatment
• Alkaline
• Wastewater Treatment
• Acid-base Chemistry
• Hydrogeology & Hydrochemistry
• Water & Wastewater Treatment
• Water & Wastewater
• wastewater
• Ocean acidification
• hydrogenated Water
• Water and Wastewater
• alkaline water ionizer
• Wastewater Engineering
• Wastewater Specialist
• Ph

6 Answers

1. go back to the requirement, and What is the pH of your influent. Adjustments start with that. use acid, or bases as you may need specifics.

2. In waste water treatment the PH control is very important role otherwise the process will be disturbed.For decreese the PH -Acid dosing and sodaash ,co2,Alkaline dosng for adjustment.

   3 Comments

   1. Thank you mohammed

   2. Thank you Christelli,Actually high PH around 8 cause in waste water is Algae growth and Low PH will cause Ammonia in lagoons so aeration,organic loading and healthy levels of nuetraints also import in system.

   3. Exactly, I agree with you, daily control needed to sustain the treatment system

3. The safest and easiest method for automated control is with the addition of carbon dioxide, if it is available as a commercial bulk supply in your area.  Minor adjustments can be handled well with cylinder quantities as well.  You are less likely to have "overshoots" with CO2 instead of lime or soda ash, and it is easier to automate.  The CO2 is much safer for workers than the caustic chemicals and their solutions.  Here's one source that also has world-wide locations: https://www.airgas.com/solutions/process-water-ph-control

   2 Comments

   1. Christelle Lwaba you could start here: https://congoindustrial.com/about-us/  They have cylinder CO2 for welding and fire extinguishers.  That may be sufficient.  If you need a bulk liquid CO2 storage and dedicated pH control system I recommend Air Liquide and subsidiaries anywhere in the world.

   2. Thanks Steven, that's great  I will check if carbon dioxide available onsite. 

4. The practical scientific method is, as stated by others, the addition of Lime or Sodium Carbonate solution. This is effected by using a smart pH sensor connected to a pH transmitter which sends the pH value to a controller. This controller has a set point and when the solution is above the setpoint, ( ie Alkaline) the controller activates a valve which adds Acid or Sodium Carbonate to the water. When the ph is low or acidic, the controller then opens a damper feeding lime or other alkaline substance into the water. The controller has a split range whereby both valves are closed at centerline ( on setpoint, 12mA output) as the alkalinity increases, so the controller output ramps up from 12 mA, until the water has returned to the setpoint and the controller output is once again center-line, 12mA. If the pH of the water drops, becoming acidic, the controller output drops from 12mA down in a sequence of steps ( controlled by the gain & Integral action settings) , thereby opening the lime or other alkaline substance valve. Once the water has returned to the setpoint, which is normally around 7.1pH ( very slightly Alkaline) this valve will close. Lime needs to flow continually, as it is a substance that solidifies when not flowing in a pipe; as such a 3 way diverter valve or an overflow weir is used to control this dosing action. A normal open/closed control vale will not function due to the coagulation of the lime in the pipe.

   1 Comment

   1. That's a great achievement Mr. Charles, thanks for your contributions. 

5. I am not a water expert. But have some experience in promoting fish ponds with fish farmers in Odisha, India. Farmers are trained to monitor water quality regularly. I know only by applying lime they reduce the acidity of the water. There are other ITK prctices like putting Banana trees( in pieces), drumstick trees( in pices). My knowledge is limited. Any fishery scientist can answer well. Thanks. Kedar

   1 Comment

   1. Thanks a lot for your contributions, I learned about natural with using banana's tree. I will try as well. 

6. Wastewater bodies??   Water pH is typically raised by controlled  lime or sodium carbonate addition. It is often lowered by controlled sulfuric acid addition. Possibly by adding sulfur dioxide which converts to sulfurous acid in water.

   1 Comment

   1. Thanks Mr. Joseph, by wastewater bodies I mean treatment plant.