The CRT-pH Series pH adjustment systems are designed for pre or post adjustment of waste stream pH values that vary in the same direction from the required value or variable pH levels in any direction. The system is an integrated design that monitors and controls pH levels within an adjustment vessel via adjustable chemical metering pump.
The system is designed for uses such as meeting discharge (6-9) requirement, metals precipitation, pH neutralization etc. Applications are reviewed and system flexibility matched to achieve required solution.
The systems are configured to control pH by metering acid, base or both to meet project requirements. The standard system design shall incorporate treatment of a continuous stream. Where desired or required the system can be configured for use on a batch basis.
Customization & modifications to fit your project needs are offered.
pH is a measure of the relative amount of hydrogen and hydroxide ions in an aqueous solution. An acid is a chemical that releases hydrogen ions when it is dissolved in water. An alkali is the opposite of an acid. It removes hydrogen ions from a solution. In any collection of water molecules a very small number will have dissociated to form hydrogen (H+) and hydroxide (OH-) ions: H2O = H+ + OH
The number of ions formed is small. At 25°C fewer than 2 x 10-7 % of the water molecules have dissociated. In terms of molar concentrations, water at 25°C contains 1 x10-7 moles per liter of hydrogen ions and the same concentration of hydroxide ions. In any aqueous solution, concentration of hydrogen ions multiplied by the concentration of hydroxide ions is constant.
Stated in equation form: Kw = [H+] [OH-] (1) where
pH is short for potential of hydrogen.
What is water pH? pH is an indication and quantification of its acid/basic properties. pH is measured on a scale of 0-14. See the reference scale for this range.
pH neutralization is required for several purposes. The most popular purposes are for precipitation of metals, breaking of emulsions, correcting pH for polymer & coagulant use and final pH correction prior to sewer discharge. If the water is basic, an acid, such as sulfuric acid is added to reduce the pH level. If the water is acidic a base such as sodium hydroxide is added to raise the pH level. The particular reagent used to raise or lower the pH is dependent on the nature of the wastewater, abilities, cost and availability of reagents as well as the preference of the end user.
Neutralization is an exothermic reaction, thus it releases energy in the form of heat, causing neutralization process systems to heat up during use. The heat energy released by a general neutralization reaction at standard temperature and pressure Uncontrolled neutralization reactions with concentrated reactants are potentially dangerous. The heat released could raise the system’s temperature past the solvent’s boiling point or cause some plastics and temperature sensitive materials to soften, distort or fail.
The amount of reagent used is dependent on the starting pH level and can be determined by a titration curve.
pH adjustment can be performed on a batch or continuous basis. The chemical metering process can be automated or manually operated as dictated by project or end user.
Typical pH Adjusting Chemicals:
Hydrochloric acid HCL
Sulfuric acid H2S04
Nitric acid HN03
Phosphoric acid H3PO4
Carbon dioxide CO2
Sodium hydroxide (caustic) NA0H
Ammonium hydroxide NH40H
Magnesium hydroxide MG[0H]2
Calcium hydroxide (lime) Ca[OH]2
*Model number indicates flow rate in GPM
*Flow based on 10 minute reaction time.
*Large sizes available.
– Frac water
– Produced water
– Biodiesel plants
– Car wash water
– Manufacturing plant water
– Wire drawing water
– Petrochemical plants
– Groundwater remediation
– Ice cream production water
– Cheese production water
– Drinking water pretreatment
– Sewage treatment plants
– Slaughter houses
– Rendering plants
The CRT-pH system can adjust water pH to any set point desired between 1-14.
Materials of construction depends on starting, end pH points and contaminants.