How to solve the problem of high alumina cement drying too quickly at the construction site?

When high-alumina refractory mortar dries too quickly at the construction site, it makes it impossible to form adhesion between the refractory bricks, affecting the construction progress. There are several solutions.

First, check the environmental temperature at the construction site. Check if the amount of water added to the high-alumina refractory mortar is insufficient or if the mixing is not uniform. The mortar may be too thick or have poor water retention, which can also cause the drying to be too fast. Additionally, if the site temperature is too high, the high-alumina refractory mortar that has been mixed should be covered with a wet cloth instead of being left exposed.

Second, during a single batch of mixing, if there is too much high-alumina refractory mortar exposed for a long time, the surface will form a crust and lose water, resulting in the drying being too fast and affecting the construction progress. It is best to mix less at a time and use it up within 30 minutes.

If the temperature and mixing are normal, adding 0.2-0.5% hydroxypropyl methylcellulose (HPMC) can delay the loss of water. You can also add 0.5-1% maltodextrin or methylcellulose to increase the stickiness and delay drying, giving enough time to build the refractory bricks. However, it is strictly prohibited to add excessive binders to avoid subsequent strength reduction and cracking between the bonding seams.

If the construction site is in a mountainous area with poor transportation or the supplier takes too long to deliver the binders, before mixing the high-alumina refractory mortar, add about 20% of drinking water, let it stand for 2-3 minutes, then add the remaining 5-10% amount, and during the mixing, a little household detergent can be dripped in to increase the stickiness and solve the problem without delaying the normal construction (this method is only applicable when the construction site is in a mountainous area with poor transportation).

In summary, all of these are remedial measures. It is best for the manufacturer to do a good job in process matching and testing during production to ensure that the powder of the high-alumina refractory mortar is above 180 mesh, with strong adhesion, and does not delay the construction time at the site.