The usage of fly ash from flue gas desulfurization to make compositions for building

Abstract

Composition for building materials comprises of fly ash from flue gas desulfurization. The fly ash (CaSO.sub.4 anhydrite), obtained from circulating fluidized bed flue gas desulfurization, is mixed with binder reactants at a ratio of 9:1. It's mainly used for non-structural cement mortar, bricks for paving walkways, brick wall decors, fire-resistant walls for interior partitions, plasterboards and so on. The binder reactants compose of 70% CaSO.sub.4.H.sub.2O, 10% Na.sub.2SO.sub.4, 10% CaO, 5% NaOH, 05% cement and 05% starch. When the binder reactants are mixed with fly ash and water (30% to 40% of the above total weight), the hydration process of CaSO.sub.4 anhydrite is accelerated.

Claims

1. The binder reactant for reusing a calcium sulfate compound comprising: approximate 70% CaSO.sub.4.H.sub.2O, approximate 10% Na.sub.2SO.sub.4, approximate 10% CaO, approximate 5% NaOH, approximate 05% cement, and approximate 05% starch.

2. The binder reactant of claim 1, wherein the calcium sulfate compound is a fly ash, CaSO.sub.4 anhydrite, essentially obtained from circulating fluidized bed flue gas desulfurization.

3. The method of making a building material: (a) mixing the binder reactant of claim 1 with the fly ash of claim 2 substantially at a ratio of 1:9 to form a pre-hydration material; and (b) mixing the pre-hydration material with water at a weight ratio of about 30% to 40%, whereby a hydration process of CaSO.sub.4 anhydrite is accelerated.

4. The method of making a building material of claim 3, wherein the building material can be used for non-structural cement mortar, bricks for paving walkways, brick wall decors, fire-resistant walls for interior partitions, or plasterboards.

5. The process of making an alternative building material: mixing the binder reactant of claim 1 with hydrated CaSO.sub.4 at a ratio about 75% w/w.

6. The process of making an alternative building material of claim 5, wherein the alternative building material can be used for non-structural cement mortar, bricks for paving walkways, brick wall decors, fire-resistant walls for interior partitions, or plasterboards.

Description

DETAILED DESCRIPTION OF THE INVENTION

[Simple Illustration]

[0006] To help the review committee better understand the technology, means and effects by which set goals are accomplished, the following case is shown in sequence and illustrated in details to provide deeper perception of the goals, features and advantages of this invention.

[The Way of Implement]

[0007] This invention involves mixing fly ash ( CaSO.sub.4 anhydrite), obtained from circulating fluidized bed flue gas desulfurization, with binder reactants at a ratio of 9:1. It's mainly used for non-structural cement mortar, bricks for paving walkways, brick wall decors, fire-resistant walls for interior partitions, plasterboards and so on. The binder reactants compose of 70% CaSO.sub.4.H.sub.2O, 10% Na.sub.2SO.sub.4, 10% CaO, 5% NaOH, 05% cement and 05% starch. When the binder reactants are mixed with fly ash and water (30% to 40% of the above total weight), the hydration process of CaSO.sub.4 anhydrite is accelerated.

##STR00001##

[0008] The products are showed in the following:

TABLE-US-00001 Category Raw Material Strength (SGS) Non-structural Cement CaSO.sub.4 anhydrite 43% 2500~3000 Lb/in.sup.2 Mortar granular CaSO.sub.4 57% Bricks for Walkways CaSO.sub.4 anhydrite 43% 2500~3000 Lb/in.sup.2 granular CaSO.sub.4 57% Wall decor and plasterboard CaSO.sub.4 anhydrite 100% 1500~1700 Lb/in.sup.2 Fire-resistant walls for CaSO.sub.4 anhydrite 43% 1000 Lb/in.sup.2 interior partitions and Hydrated CaSO.sub.4 57% plasterboards

[0009] The above products satisfy the demands and standards of normal building materials. Only 10% binder reactant by weight of the above by-products is needed to produce building materials that meet standard construction strength requirement.

[0010] From the above procedures, it can be seen that the binder reactant of this invention can accelerate the hydration reaction of the fly ash, which provides a great variety of applications, in contrast to prior art.

[0011] The invention has been described in detail with particular reference to certain preferred embodiments thereof and it is intended that the specification and examples be exemplary only. It should be appreciated that variations and modifications can be effected within the spirit and scope of the invention.