A method for preparing low-fired composite cement by using waste concrete cement stone phase

Abstract

A method for producing low combustion composite cement from a waste concrete cement stone phase belongs to the field of cement production, solves the problem of resource utilization of the waste concrete cement stone phase, and can also realize large dosage use of industrial waste residues. The low combustion composite cement comprises the following raw materials by weight: 50%-70% of dehydrated cement stone powder, 2%-5% of dihydrate gypsum, 1.5%-3% of anhydrous sodium sulphate, 25%-40% of mineral powder and 0%-20% of other mixtures. The low combustion composite cement has the advantages of simple preparation process, the waste concrete cement stone phase is efficiently used, the cement production cost is greatly reduced by low temperature firing technology, consumption of natural resources and environmental pollution can be effectively reduced, and the method has obvious low carbon environmental-friendly effects and remarkable comprehensive benefits.

Description

technical field [0001] The invention discloses a method for preparing low-fired composite cement by using waste concrete cement stone phase, which belongs to the field of cement production. Background technique [0002] With the implementation of the sustainable development strategy, the resource, energy and environmental problems brought by the cement industry have become the main factors restricting its development. Using less Portland cement clinker and using as much solid waste as possible to produce cement is a topic with environmental protection significance and economic value. As an important component of solid waste, the utilization of waste concrete is an important aspect of the current solid waste resource utilization. Recycled concrete technology can better solve the problem of recycling waste concrete, and is of great significance to protecting the environment and saving natural resources such as sand and gravel. However, it has not been realized for the cement ...

AI Technical Summary

Problems solved by technology

[0004] The analysis shows that the root cause of the low strength of the dehydrated cement stone gelling system is that the particle hardness of the loose and porous dehydrated cement stone is extremely low. On the one hand, the particle size of the dehydrated cement stone after grinding is still relatively coarse, which affects its gelling ability On the other hand, the gelling system cannot form an effective support structure, which leads to poor mechanical properties in the later stage.

Only by overcoming the two adverse effects caused by low particle hardness can the problem of low strength of the dehydrated cement stone gelling system be completely solved

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