Admixture makers often blend calcium lignosulfonate with sulfonated naphthalene formaldehyde (SNF) or polycarboxylate ether (PCE). Lignosulfonate adds low cost and set delay; SNF or PCE add water reduction. This page covers why blends are made, how to screen them and what to test.
What Each Component Brings
| Component | Class alone | Role in a blend |
|---|---|---|
| Calcium lignosulfonate | Normal range (ASTM C494 Type A or D) | Cost, set delay, some water reduction |
| SNF | High range (Type F or G) | Main water reduction |
| PCE | High range (Type F or G) | Main water reduction and slump retention |
| Sodium gluconate | Retarder | Extra set delay at low dose |
A full comparison of the three water reducers is on calcium lignosulfonate vs SNF vs PCE. SNF data: SNF superplasticizer.
Screening a Blend
- Fix the total solids dose and vary the ratio, for example 0, 25, 50 and 75% lignosulfonate.
- Measure paste or mortar flow at 0 and 60 minutes.
- Measure setting time for each ratio.
- Take the best two ratios into concrete trials.
- For liquid blends, store samples for several weeks and check for separation or sediment.
Concrete Tests for the Final Blend
| Property | Test |
|---|---|
| Water reduction | Against control at same slump (ASTM C494 or EN 934-2) |
| Slump retention | Slump at intervals after mixing |
| Air content | ASTM C231 or EN 12350-7 |
| Setting time | ASTM C403 |
| Strength | ASTM C39 or EN 12390-3 |
Grade Data
| 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.
Frequently Asked Questions
Why blend calcium lignosulfonate with SNF or PCE?
To combine the low cost and set-retarding effect of lignosulfonate with the higher water reduction of SNF or PCE. The blend ratio is set by trial.
Is calcium lignosulfonate compatible with PCE?
It depends on the PCE and the cement. Test the blend in paste or mortar for flow and flow loss, and watch for separation in liquid blends during storage.
Can the blend reach high-range performance?
A blend is classed by test. If the finished admixture meets ASTM C494 Type F or G, or EN 934-2 Table 3.1 (at least 12% water reduction), it can be sold as high-range.
What other components are common?
Sodium gluconate is often added as a retarder, and defoamers or air entrainers to control air. Each changes the result, so test the full formula.
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: is it a superplasticizer? · admixture compatibility testing · all construction uses
