32.5 modified mixed Portland cement and preparation method thereof

Abstract

The invention discloses a 32.5 modified mixed Portland cement and a preparation method thereof. The cement comprises, by mass, 45.0-68.0% of Portland cement clinker and gypsum, 5.0-25.0% of limestone,0-0.5% of a grinding aid and 0.02-5.5% of a modifying component, and also includes 5.0-45.0% of one or more of granulated blast furnace slag, granulated blast furnace slag powder, a vulcanic ash mixture and a fly ash-containing active or non-active mixture, and 8.0% or below of other incorporation-allowed waste slag. The raw materials have wide sources, and the preparation method is not complicated, relates to the fields of comprehensive utilization of cement, concrete, mortar and solid wastes, and meets the conditions of the process for preparing the cement product containing the modifyingcomponent. The cement improves the homogeneity, the workability, the durability and other performances of concrete and mortar prepared from the cement, increases the construction efficiency, and facilitates of comprehensive utilization of resources, energy saving and emission reduction.

Description

technical field [0001] The invention relates to the fields of cement and concrete production technology and solid waste comprehensive utilization, in particular to a 32.5 modified mixed portland cement and a preparation method thereof. Background technique [0002] According to national statistics, in 2018, the national annual output of cement was 2.18 billion tons, and the output of ready-mixed concrete was 1.796 billion cubic meters. If the average amount of cement per cubic meter of concrete is calculated as 0.28 tons, the corresponding cement consumption is only about 500 million tons. Although the amount of concrete mixed in key projects such as highways and high-speed rail may not be included in the statistics of concrete production, it can be analyzed from it that there are still A large amount of cement is used to mix concrete at rural construction sites. [0003] According to statistics, C15-C30 strength grade concrete accounts for more than 75% of all concrete, an...

AI Technical Summary

Problems solved by technology

[0006] At present, the domestic new-type dry cement production process accounts for more than 98%, and large-scale storage warehouses are generally used, with a small number, and most enterprises basically do not have storage and batching warehouses for mixed materials (including composite) micropowder, corresponding secondary batching, measurement, etc. The equipment and facilities rarely consider the process conditions of adding admixtures or are extremely imperfect; due to the traditional cement production method, the temperature of the cement after the mill is as high as 100-120 ° C, and from the mill to the site of use, the cement is in a sealed storage and transportation facility In equipment and means of transportation, the heat of cement cannot be dissipated in time. If admixtures (modified components) are added when the cement temperature is high, the molecular structure will be changed, which will seriously affect the functions of some admixtures and the interaction with cement. Capacitance, as well as concrete durability, volume stability, construction and other properties

According to the actual conditions of the current cement enterprises and their production processes, it is difficult to prepare cement products with multiple varieties and admixtures

Images