A ball mill grinding ball and a method for improving the performance of construction waste recycled concrete aggregate

Abstract

The invention discloses a ball mill grinding ball and a method for improving the performance of construction waste recycled concrete aggregate. Multiple rows of pits are formed in the surface of the ball mill grinding ball in the circumferential direction, and the pits are in the shape of a spherical crown. The method comprises the steps that first-stage jaw crushing processing is firstly performed on construction waste concrete blocks to obtain recycled concrete aggregate, then the recycled concrete aggregate processed through jaw crushing is mixed with the grinding ball, ball grinding two-stage processing is performed for 1-5 min, and finally the recycled concrete aggregate processed through ball grinding is sieved to obtain the recycled concrete aggregate conforming with the grain size distribution requirements. According to the ball mill grinding ball and the method, crack damage remained on the surface and interior of the recycled concrete aggregate due to crushing processing can be reduced, the weak components on the surface of the aggregate are rubbed off through the grinding ball with the pits in an extruding mode to enable the aggregate to approach to be in a ball shape, grain shaping is achieved, the physical performance of the construction waste recycled concrete aggregate is further improved, the crushing performance of the aggregate is especially improved, the water absorption is especially lowered, and resource recycling of construction waste is promoted.

Description

technical field [0001] The invention belongs to the technical field of construction waste resource utilization, and in particular relates to a ball mill grinding ball and a method for improving the performance of construction waste recycled concrete aggregate. Background technique [0002] In recent years, as my country's urbanization process continues to accelerate, the scale of cities has expanded accordingly. At the same time, more and more old, old, and dangerous buildings need to be demolished, resulting in an increase in the amount of construction waste generated year by year. A large amount of construction waste not only occupies a large amount of land, but also brings serious environmental problems. [0003] Abandoned concrete blocks and waste bricks in construction waste can be used as raw materials for building materials regeneration or to produce recycled building materials products, and are important substitutes for natural sand and stone materials. The resource...

AI Technical Summary

Problems solved by technology

First of all, since the recycled coarse aggregate contains about 30% hardened cement mortar (the cement mortar is wrapped on the surface of the natural aggregate or exists in the form of debris), compared with the natural sandstone coarse aggregate, its water absorption, apparent density, etc. Various physical properties are different from natural aggregates; secondly, the quality and particle size of recycled aggregates are related to the strength of original concrete, and the quality of recycled aggregates generally increases with the increase of original concrete strength; thirdly, the surface of recycled coarse aggregates Rough, with many edges and corners, the surface of the aggregate contains a large amount of cement mortar that has not fallen off and has a relatively large porosity. In addition, the recycled coarse aggregate itself has a large number of microcracks formed when it is broken, which will increase the water absorption of the recycled coarse aggregate. Affect its physical properties and performance

[0007] At present, traditional construction waste concrete block crushing technologies, such as jaw crushing, hammer crushing, counterattack crushing, and double-rotor horizontal crushing, are based on high-frequency and high-speed impact on materials, and the recycled aggregate produced after processing has relatively sharp edges and corners. Many, and there are many flaky and needle-like aggregate particles (needle-shaped particles refer to the particles whose length of concrete recycled coarse aggregate is greater than 2.4 times the average particle size of the corresponding particle size; flaky particles refer to the thickness less than particles with an average particle size of 0.4 times), while obtaining the granular aggregate, a large number of crack damages are left on the surface and inside of the aggregate, which seriously affects the physical properties and performance of the recycled aggregate

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