Emulsified asphalt has two foam sources: the emulsifier soap solution foams on its own under high-speed agitation, and after the asphalt and soap pass through the colloid mill the finished tank goes through another round.
In road materials, Chemi Tech brings emulsified asphalt, modified emulsified asphalt and cold patch mixes into a low-foaming defoamer programme led by polyether systems, matched to soap concentration, shear intensity and storage period.
Business Advantages
First, foam breaks fast and the finished tank does not overflow after milling. From soap make-up to the colloid mill outlet the foam falls away quickly and tank capacity is used better.
Second, suppression is steady: no foam returns during long storage. After the product stands for a few days the surface foam layer is thin and tanker loading carries less air.
Third, it is compatible with breaking and does not slow set. It does not affect breaking speed or aggregate coating, so the set rhythm after paving stays as it was.
Fourth, residue is low and evaporation residue figures are not disturbed. The components disperse fully, leaving residue and penetration unaffected.
Boundary on these figures: the conclusion comes from conventional emulsified asphalt production. Change the emulsifier type or the soap recipe and it differs. Run a small-scale trial before scaling production.
Industry Pain Points and Solutions
Foam control in emulsified asphalt gets caught at three points: the soap foams on its own, the colloid mill shears hard, and the finished product is stored for a long time. Let go of any one of them and the foam comes back.
Pain point one: foam already forms at the soap make-up stage. High-concentration emulsifier plus high-speed agitation stacks foam to the tank mouth. The answer is a low-foaming compatible defoamer system.
Pain point two: foam rises again after the colloid mill. Shear drags air into the liquid and the finished tank level reads falsely high. The answer is greater shear tolerance and longer hold.
Pain point three: the defoamer affects breaking and specification figures. Too much and set is slower, with evaporation residue fluctuating too. The answer is to verify compatibility and specification together in one round.
The route on site is also three steps: reproduce the foam on your own soap recipe first, then run a trial on a small colloid mill, and finally fix the type and the addition point.
Typical Conditions and Verification
Soap temperature is generally held around seventy degrees Celsius, emulsifier concentration is adjusted to the recipe, and the colloid mill runs at high speed with strong shear. Foam peaks at two points: when soap make-up is complete and at the colloid mill outlet sample point.
Failure signals often come up in four places: the finished tank level reading falsely high and a thicker foam layer after standing; the pump carrying air during loading; evaporation residue running low; breaking time lengthening after spraying. Two of those and the trial deserves a re-check.
Site operating data at the same soap recipe is held by the technical team as comparable records and can be requested.
FAQ
Q1: Why does emulsified asphalt need a dedicated defoamer?
General-purpose products often fail under high temperature and high shear, and can compete with the emulsifier for the interface, which sends breaking time and storage stability into fluctuation.
Q2: Will evaporation residue and storage stability drift after adding it?
Both depend on the specific dosage. Run a gradient trial on the same soap batch and judge from evaporation residue and storage stability rather than concluding from a single result.
Q3: Which steps matter when replacing an imported defoamer with a domestic one?
Record the original dosage, the finished tank foam height and the breaking time as a baseline first, reproduce them equivalently on the same soap recipe, then run a parallel observation period and scale up once the figures match.