Compared to caustic soda, magnesium hydroxide is very safe and will not raise the pH above 8.0. Magnesium hydroxide works better if it can be made into a slurry before being added into the anaerobic system.
Use Boost N Lock to finish the pH adjustment to improve pH stability.
Exact Dosing Bench Test
- Prepare Chemicals: Make a slurry mixture of 50g of magnesium hydroxide and 1000 mL of distilled water. Add the slurry to a bottle with a cover so it can be shaken up regularly.
- Prepare Sample to Be Tested: Collect 500 mL of well-mixed (if possible) anaerobic digester sample in a 1000 mL beaker. Place the beaker on a mixing plate with a magnetic stir or put in a 1000 mL beaker with mixing.
- Add Magnesium Hydroxide Until Desired pH is Achieved: Test and record the initial pH, then add 5 mL portions of magnesium hydroxide. After each 5 mL magnesium hydroxide addition, mix the digester sample for 3 minutes and then test and record the pH and add another 5 mL until the pH is at 7. Magnesium hydroxide should be shaken or mixed before each 5 mL addition.
- Calculate Dose Required for Full Scale Treatment: Once the pH reaches 7, the dose of 5 mL equates to 210# of magnesium hydroxide per 100,000 gallons digester volume. This means you will need to add 210 pounds of Boost N Lock per 100,000 gallons digester volume or other solid pH adjuster for each 5 mL added to the beaker.
Applications and Benefits
- Great for neutralizing acid waste stream
- Works better in digester with good mixing
- Recovery if an anaerobic system goes sour
- Safe to handle and safer for your system