Which method is NOT used to provide excess moisture during the curing stage?

Applying silicone sealant is not a method used to provide excess moisture during the curing stage of refractories. The primary purpose of silicone sealants is to create a moisture barrier, which can prevent the absorption of water and inhibit the curing process. In contrast, the other methods mentioned are intended to enhance the moisture content available to the refractory during curing.

Wetting with a fine water spray introduces moisture directly onto the surface of the refractory material, ensuring that it retains the necessary water for proper hydration and curing. Using a membrane type curing compound creates a film that retains moisture close to the surface of the material, minimizing evaporation and assisting in maintaining the necessary humidity levels. Avoiding air drying for more than 2 hours helps to ensure that the refractories do not dry out too quickly before they have had a chance to cure properly.

Therefore, among the options provided, the application of silicone sealant does not contribute to providing excess moisture during curing, making it the correct answer to the question.