Method of preparing baking-free load-bearing bricks through steam curing of semidry desulfurization residues

Abstract

The invention discloses a method of preparing baking-free load-bearing bricks through steam curing of semidry desulfurization residues, belonging to the technical fields of environmental engineering and preparation of construction material. According to the invention, a gelling agent is prepared from semidry desulfurization slag and multi-component powder and is uniformly mixed with inert sandy aggregate in a mixer, water accounting for 10 to 46% of the mass of solid powder is added and uniformly mixed with the solid powder, an obtained mixture undergoes pressure forming and demolding so as to obtain green bricks, and the green bricks are subjected to steam curing at a temperature of 40 to 90 DEG C for 1 to 7 d so as to obtain baking-free bricks with sufficient strength; the baking-free bricks can meet different strength requirements for load-bearing bricks of a model number in a range of MU10 to MU30, have excellent water resistance and can be used as exterior wall tiles. According to the invention, the problem that comprehensive utilization of semidry desulfurization gypsum is not easy due to complex composition of the semidry desulfurization gypsum is overcome; effective usage of solid waste in production of the baking-free bricks which cost less than conventional sintered clay bricks do has great significance to energy conservation and environmental protection.

Description

technical field [0001] The invention belongs to the technical field of environmental protection engineering and preparation of building materials, and in particular relates to a method for preparing fire-free load-bearing bricks by steaming and curing semi-dry desulfurization waste residue. Background technique [0002] Desulfurization and purification of coal-fired flue gas before discharge into the atmosphere is a rapidly developing environmental protection technology at home and abroad. It has been widely used in various major industrial fields. When lime or slaked lime is used as the desulfurization medium, a large amount of desulfurization gypsum will be produced. Early desulfurization technologies were mainly wet and dry. Wet desulfurization produced a large amount of sludge-like desulfurization gypsum, while dry desulfurization products were generally discharged together with fly ash or slag, and desulfurization gypsum would not be discharged separately . Wet desulfu...

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Problems solved by technology

However, this kind of mortar also has the following problems: ① Its early strength is low, which limits its application; ② The amount of desulfurization slag in the mortar is too low, which makes the cost of this kind of dry-mixed mortar relatively high, and It is not conducive to the large-scale treatment and utilization of desulfurization slag; ③The long-term durability of this kind of construction mortar has not been verified. Experiments show that due to the influence of delayed formation of ettringite, its long-term strength may be seriously reduced or even cracked due to expansion. The risk of its application cannot be ignored

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