AQUAMAG® For SOx Scrubbing

Background

Currently, caustic soda is the most commonly used chemical in SOx scrubbers for pH control. With the price of caustic soda elevated, manufacturing and power plants evaluate methods for usage reductions of caustic soda. One method of caustic soda reduction and cost savings is the use of AQUAMAG® Magnesium Hydroxide slurry in SOx scrubbers.

Application

The typical AQUAMAG® addition point is the same location as the caustic soda addition point in the SOx Scrubber. With the use of AQUAMAG®, 30% reduction in chemical consumption is estimated compared to caustic soda on a dry basis. AQUAMAG® usage is advised for scrubbers that are either venturi or randomly packed scrubbers. If the scrubbing column is randomly packed, we advise engineering data be reviewed to insure packing does not go dry.

Chemistry

Below are three series of reactions which occur in the magnesia scrubbing-regeneration process. In the first series, the following reactions predominate. Sulfur dioxide absorption is represented by the formation of magnesium sulfite hexahydrate followed by its further reaction with sulfur dioxide to form magnesium bisulfite, see reactions 12.1-12.3:

  • SO2 + Mg(OH)2 + 5H2O ? MgSO3.6H2O? (12.1)
  • SO2 + MgSO3.6H2O ? Mg(HSO3)2 + 5H2O (12.2)
  • Mg(HSO3)2 + Mg(OH)2 + 4H2O ? 2MgSO3.6H2O? (12.3)

AQUAMAG® Pricing:

For use in the savings example below, we have assumed an AQUAMAG® price of $400.00/dry ton delivered. (Please contact your Premier sales representative for specific pricing applicable to your account and plant location.)

Savings Example:

Below is a chart of estimated cost savings for the use of AQUAMAG® vs. caustic soda.

Current 50%Caustic Soda Flow (GPM) Savings at Caustic Price $300.00 Savings at Caustic Price $350.00 Savings at Caustic Price $400.00 Savings at Caustic Price $450.00 Savings at Caustic Price $500.00
0.5 $15,087 $52,806 $90,525 $128,244 $165,963
1.0 $30,175 $105,613 $181,051 $256,489 $331,927
1.5 $45,262 $158,419 $271,576 $384,733 $497,890
2.0 $60,350 $211,226 $362,102 $512,978 $663,854
2.5 $75,438 $264,033 $452,628 $641,223 $829,818
3.0 $90,525 $316,839 $543,153 $769,467 $995,781
3.5 $105,613 $369,646 $633,679 $897,712 $1,161,745

Advantages:

  1. Stable Pricing compared to Caustic Soda.
  2. Safe, non-hazardous, both for the environment and personnel.
  3. Readily available, multiple manufacturing locations in U.S.A.

Plant Trials

Premier Chemicals, LLC field service personnel can provide assistance in running product plant trials in your SOx scrubber. The product trial will show the effectiveness/cost savings of AQUAMAG®. The cost for doing a trial is the freight cost to bring equipment to your plant site and the cost of AQUAMAG® used during the trial only.