Abstract: Deposits are removed from surfaces by contacting the deposits with a deposit-removing liquid composition containing a substance which produces gas bubbles, and thereby stirs the liquid, at the conditions at which the deposits are contacted with the liquid. Where the substance is one which is a gas at atmospheric conditions but dissolves in the liquid at a super-atmospheric pressure, such as carbon dioxide, the pressure exerted on the composition while contacting the deposits is repeatedly raised and lowered whereby the gaseous substance is repeatedly liberated from solution and placed back into solution to promote agitation of the liquid.

Abstract: A method for passivating acid-cleaned ferrous metal surfaces is disclosed. The method features the use of an aqueous passivating solution having a pH of greater than about 8, comprising a base, an oxygen containing gas, and one of hydrazine, an iron complexing agent and mixtures thereof, wherein the method comprises contacting an acid-cleaned ferrous metal surface with the passivating solution at temperatures up to about 400.degree. F or greater.

Abstract: Iron containing scale is removed from a metallic substrate by contacting the scale with a composition which is an aqueous solution consisting essentially of at least 0.5 weight percent of a polyphosphonic acid, or an alkali metal or amine salt of such acid, with the acid being selected from the group of acids having the formulae: ##STR1## where R.sub.1 is selected from the class consisting of C.sub.1 -C.sub.12 alkyl groups, and the group ##STR2## and ##STR3## where R.sub.2 is selected from the class consisting of --H, --PO.sub.3 H.sub.2, C.sub.1 -C.sub.12 alkyl groups, and the group ##STR4## The scale is removed from the metallic substrate by contacting THE DESCRIBED SCALE-BEARING SUBSTRATE WITH THE DESCRIBED COMPOSITION AT SELECTED TEMPERATURE AND PH conditions, and over a controlled time period and iron concentration in the composition so that the formation of an undesirable polymeric precipitate in the cleaning solution is avoided.

Abstract: An alkali metal silicate foam composition comprising preferably sodium silicate, cementing agent such as sodium silicofluoride, gelling agent such as linoleic acid and filler such as glass fiber mixed with water and blowing agent to provide foams having high strength, high water resistance and low shrinkage upon curing. Amides and halo-alcohols are used as gelling agents in preferred compositions for exceptional strength and water resistance. Vermiculite and perlite are preferred fillers for a low shrinkage foam composition.