A kind of construction waste regenerated highly active mineral admixture and its preparation

Abstract

The invention discloses a regenerated high-activity mineral admixture prepared through resourceful utilization of construction waste and metallurgical waste residue, and a preparation method thereof. The method comprises the following steps: crushing waste concrete so as to obtain cement stone flour; mixing 70 to 98 wt% of cement stone flour, 0 to 25 wt% of metallurgical waste residue and 1 to 5 wt% of floating beads, adding water accounting for 10 to 15% of the total mass of cement stone flour, siliceous metallurgical waste residue and floating beads into the obtained mixture and carrying out drying so as to obtain slag stone flour; calcining the obtained slag stone flour at a temperature of 800 to 1000 DEG C for 15 to 20 min so as to obtain calcined slag stone flour; and mixing 50 to 70 wt% of calcined slag stone flour and 30 to 50 wt% of blast furnace slag powder so as to obtain the regenerated high-activity mineral admixture. According to the invention, solid waste like construction waste, metallurgical waste residue, floating beads and the like is used, so components of the mineral admixture are simple and manufacturing cost is low; and the mineral admixture has high activity and can effectively reduce the amount of cement in preparation of high performance concrete.

Description

technical field [0001] The invention belongs to the category of inorganic non-metallic building materials, and in particular relates to a preparation method of a regenerated high-activity mineral admixture for resource utilization of construction waste and metallurgical waste slag Background technique [0002] The traditional cement industry is an industry with huge energy and resource consumption and serious environmental load. It is very important to develop new auxiliary cementitious materials, which can replace some cement to a certain extent and reduce cement production, thereby reducing energy, resource consumption and environmental load. meaning. At the same time, industries such as metallurgy, ceramics, electroplating, and batteries produce a large amount of industrial waste slag every year. The random stacking of these waste slags takes up a lot of valuable land resources. At the same time, some heavy metals in them are easy to cause secondary pollution to the envir...

AI Technical Summary

Problems solved by technology

At the same time, industries such as metallurgy, ceramics, electroplating, and batteries produce a large amount of industrial waste slag every year. The random stacking of these waste slags takes up a lot of valuable land resources. At the same time, some heavy metals in them are easy to cause secondary pollution to the environment. The demolition of old buildings and engineering structures produces an astonishing amount of construction waste. The disposal and piling of these construction wastes also has the problems of wasting land resources and causing environmental pollution.

[0003] For the recycling of construction waste, at present, it mainly focuses on the recovery of coarse and fine aggregates in construction waste, and uses them to prepare recycled aggregates and apply them to concrete. The cement stone components are basically in an unused state. For some active Low industrial waste residue is only used as an ordinary backfill material, and its utilization value is not high. At the same time, for the development of some waste concrete recycled cementitious materials, there is also a problem of poor stability due to the high content of f-CaO in it, so that Applications of recycled cementitious materials are limited

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