Industrial Wastewater Neutralization Using Magnesium Hydroxide May 15, 2012 Steve Leykauf, Presenter
Discussion Topics What is Magnesium Hydroxide? Technical Benefits of Magnesium Hydroxide Economic Benefits of Magnesium Hydroxide Product Application
What Is Magnesium Hydroxide?
What Is Magnesium Hydroxide? React Magnesium Chloride Rich Brine with Dolomitic Lime CaCl 2 + MgCl 2 + H 2 O + CaO.MgO Manistee, MI - Brine Chemical Reaction Yields Mg(OH) 2 Milk of Magnesia! Woodville, OH Dolomitic Lime Magnesium Hydroxide Slurry
Magnesium Hydroxide Suspension Slurry Properties Typical Dry Solids, % 61.0 Bulk Density, lb/gal 12.8 Mg(OH) 2 Contained, lb/gal 7.7 Viscosity, cps 250 Mg(OH) 2 (dry basis), % 98.8 Median Particle Size, micron 3.0 % Passing 325 Mesh Screen 99.8
Wastewater Applications Acid Neutralization ph Adjustment Heavy Metal Precipitation Aerobic Wastewater Treatment Anaerobic Wastewater Treatment
Applications Chemical Processing Plants Food & Beverage (Biological) Heavy Metal Precipitation Municipalities Power Utility Plants Pulp & Paper
Technical Benefits
Technical Benefits Optimal Neutralizing Value Greater alkalinity contribution (pound for pound) Improves Biological Activity Magnesium is a nutrient provides ideal ph range Buffering Ability Naturally buffers at ~9.0 ph precluding ph excursions Will not endanger biomass Metals Removal Through precipitation and adsorption
Technical Benefits Improved Sludge Settling Less sludge volume compared to other alkalis Safe Non hazardous (by D.O.T. Standards), non corrosive, and safe for EMPLOYEES Environmentally Friendly Non Toxic to environment
Properties of Industrial Alkalis Mg(OH) 2 Ca(OH) 2 NaOH Na 2 CO 3 Alkalinity (lbs CaCO 3 per lbs dry solids) 1.68 1.32 1.23 0.944 % Solids 61 34 50 n/a Alkalinity (lbs CaCO 3 per gallon) Neutralizing Capacity (lbs OH - per lb dry solids) 13.38 4.68 7.61 n/a 0.572 0.450 0.425 0.322
Replacement Capacities of Mg(OH) 2 Slurry One (1) Gallon of Magnesium Hydroxide Slurry Replaces: 1.77 Gallons of 50% Caustic Soda (NaOH) 7.69 Pounds of CaO (Dry Solids) 2.85 Gallons of 34% Ca(OH) 2 Slurry 14.17 Pounds of Na 2 CO 3 (Dry Solids)
ph Relative Volume Mg(OH) 2 Efficiency Charts Dry Pounds of Neutralization Agent Required to Neutralize One Ton of Acid 6.0 Relative Sludge Volumes Using Various Alkalis 3000 5.0 2500 4.0 2000 1500 1000 500 0 Mg(OH)2 Ca(OH)2 NaOH Na2CO3 Sulfuric Hydrochloric 3.0 2.0 1.0 0.0 FloMag H/HUS Ca(OH)2 NaOH Titration Curves for Various Alkalis 14 12 10 8 6 4 2 0 0 50 100 150 200 Titration Percent Lime Caustic Soda FloMag H/HUS
Summary of Benefits vs. Caustic Soda Supplies 32% More CaCO 3 Alkalinity 1.68 Lbs of CaCO3 per Lb of Mg(OH) 2 Only 1.23 Lbs of CaCO3 per Lb of NaOH Much Safer to Handle Low Solubility = Longer Lasting Alkalinity and ph Control Provides Soluble Magnesium Essential for Cellular Respiration of Biomass Buffers to ph of 9.0 Caustic Soda ph excursions can be detrimental to biomass
Economic Benefits
$ Per Dry Ton Caustic Soda Pricing (Dry Ton Basis) $1,000 $900 $800 $700 $600 $500 $400 $300 $200 $100 $0 NaOH Mg(OH)2 Source: Chemical Week; MMMS Sources
Economic Benefits Caustic Soda Price Volatility Leads to Economic Uncertainty 1. Notice Magnesium Hydroxide Price Stability 2. Use Less Magnesium Hydroxide Slurry due to its higher alkalinity contribution per gallon! Cost Summation Over 4 ½ Years Suggests... Magnesium Hydroxide Slurry is 50% Less Expensive Than Caustic Soda!
Economic Benefits Consider All Cost Reductions: Less Chemical Use Sludge Disposal Costs Costs for Acids Costs for Polymers Reduced Transportation Costs
Product Application
Product Application Magnesium Hydroxide is a Suspension Intermittent Agitation Complete Wastewater Profile Form Determines Candidacy for Success Perform Laboratory Titrations Develop Comprehensive Report Describing Technical / Economic Merit Engineers Make Equipment Recommendations
Product Application Equipment Skid-Mounted Mg(OH) 2 Tote System with Agitator, Feed and Transfer Pumps Twin 2500-gallon Mg(OH) 2 Storage Tanks with Pump House
Thank You! Steve Leykauf 574-277-2237 steve.leykauf@martinmarietta.com