Calcium lignosulfonate is a normal-range water reducing agent for concrete and mortar. It is supplied as powder or as a ready-made solution. This page gives the dosage, the expected water reduction, how to dose the solution and what to check in a trial.
Key Numbers
- Dosage: 0.20–0.30% by weight of cement (GAC-CaLS-Construction TDS).
- Water-demand reduction: up to 12% (same TDS).
- Class: ASTM C494 Type A or D; EN 934-2 Table 2 (at least 5%).
- Solution: 45% min solids, density 1.265 g/ml.
Powder or Solution
| Parameter | Construction Grade (GAC-CaLS-Construction), TDS Rev. 2.0 |
|---|---|
| Form | Light brown powder |
| Bulk density | 0.8 g/cm³ |
| Moisture | 5% max |
| pH (5% solution) | 4–6 |
| Recommended dosage | 0.20–0.30% by weight of cement; higher dosages may retard set beyond specified limits |
| Water-demand reduction | Up to 12% |
| Packaging | 25 kg woven bags with PE liner; 500 kg or 600 kg jumbo bags |
| Shelf life | 12 months |
| Parameter | Liquid Calcium Lignosulfonate (GAC-CaLS-L), TDS Rev. 2.0 |
|---|---|
| Solid content | 45% min |
| Lignosulfonate content | 45% min (dry basis) |
| Reducing sugar | About 4% |
| Density | 1.265 g/ml |
| pH | About 5.0 |
| Packaging | Flexitank or IBC |
Typical values from the current TDS. Each lot ships with a COA.
Dosing the Solution
| Step | Example |
|---|---|
| 1. Set the dry-basis dose | 0.25% of cement mass |
| 2. Divide by the solids fraction | 0.25 ÷ 0.45 = 0.56% of cement as solution |
| 3. For 350 kg cement per m³ | 350 × 0.0056 = 1.94 kg solution per m³ |
| 4. Convert to volume | 1.94 ÷ 1.265 ≈ 1.5 l per m³ |
Add the solution with the mixing water or just after it, and keep the same point in every batch. Account for the water in the solution when calculating the water-cement ratio.
Performance Checks
| Property | Test | What to look for |
|---|---|---|
| Slump | ASTM C143 or EN 12350-2 | Same slump at lower water, or higher slump at same water |
| Air content | ASTM C231 or EN 12350-7 | Change from control |
| Setting time | ASTM C403 | Delay within the allowed window |
| Strength | ASTM C39 or EN 12390-3 | At least equal to control at 7 and 28 days |
Why It Is Normal Range
Its dispersing power is moderate, so it is classed as a normal-range reducer. For larger water cuts it is blended with SNF or PCE (blending guide). A comparison is on calcium lignosulfonate vs SNF vs PCE.
Frequently Asked Questions
How much water does calcium lignosulfonate save?
The GAC-CaLS-Construction TDS gives up to 12% water-demand reduction at 0.20–0.30% by weight of cement. Confirm the figure in a trial with your cement and aggregates.
Can it be used as a solution?
Yes. The liquid grade is supplied at 45% min solids. Convert the dry-basis dose: 0.25% of cement as dry powder is about 0.56% as 45% solution.
What class of water reducer is it?
Normal range: ASTM C494 Type A (or Type D when it also retards) and EN 934-2 Table 2, which requires at least 5% water reduction.
Does it entrain air?
Lignosulfonates can add some air. Measure air content (ASTM C231 or EN 12350-7) in the trial mix.
Samples and Documents
Send the cement type, mix design, target slump or setting time, and the test standard you work to, to info@greenagrochem.com or use the contact form.
Related: ASTM C494 Type A and D · EN 934-2 and GB 8076 · all construction uses
