CN101734892A

CN101734892A - Method for recycling waste concrete

Info

Publication number: CN101734892A
Application number: CN200910311416A
Authority: CN
Inventors: 杨波; 李洪军; 单文武; 王从军
Original assignee: Huaian Jieda Concrete Co Ltd
Current assignee: Huaian Jieda Concrete Co Ltd
Priority date: 2009-12-15
Filing date: 2009-12-15
Publication date: 2010-06-16

Abstract

The invention discloses a method for recycling waste concrete, which comprises the following steps: (1) crushing the waste concrete (which can contain mortar) in a crusher into a grain diameter of less than or equal to 20 mm, removing impurities, such as metal, wood and plastic, putting the waste concrete into a ball mill, simultaneously adding a concrete excitant accounting for 3 to 5 percent of the weight of the waste concrete, and milling the waste concrete into a specific surface area of more than or equal to 390 square meters per kilogram; and (2) mixing the recycled admixture with the specific surface area of more than or equal to 390 square meters per kilogram obtained from the step (1) and cement, medium-coarse sand, macadam with 5 to 25 mm, water and a concrete admixture in part by weight: 80 to 120 parts of the recycled admixture, 230 to 300 parts of the cement, 710 to 800 parts of the medium-coarse sand, 900 to 1,200 parts of the macadam, 160 to 200 parts of the water, and 4 to 6 parts of the concrete admixture to prepare the recycled concrete.

Description

A kind of discarded concrete recycling method

Technical field:

The present invention relates to concrete, be specifically related to the recycling method of discarded concrete.

Background technology:

China city is in process of construction, and all will produce a large amount of building wastes every year.Building waste also claims solid waste, generally comprises concrete, mortar, brick, tile, metal, timber and other.The buildings of the large percentage that concrete wherein accounts for, especially skeleton construction, concrete accounts for more than 60% in its solid waste.

At present, be that it is transported to the appointed place backfill mostly to the treatment process of discarded concrete, so not only take a large amount of soils, and contaminate environment, be unfavorable for Sustainable development.In the last few years, the sector proposed the stone in the discarded concrete is reclaimed in the recovery of trying to explore to study discarded concrete, utilization, used in the concrete as regeneration aggregate and natural gravel mixing.But because regeneration aggregate adheres to the mortar of inequality, cause index instabilities such as the crush index of such regeneration aggregate and water-intake rate, have a strong impact on the physical and mechanical property of institute's concrete batching.In order to address this problem, the sector proposes again after the discarded concrete fragmentation, and the water flushing realizes the recovery of stone, mortar etc.As the patent No. is that ZL02208024,4 discloses a kind of discarded concrete sandstone pulp-water retrieving arrangement, after the discarded concrete fragmentation, separate shake out, stone, pulp-water, again as the raw material of commerical ready-mixed concrete.And for example number of patent application is that 200810049442X discloses discarded concrete reclaiming method and device, be will be through removing reinforcing bar processing, granularity after the process of the discarded concrete about 400mm crusher in crushing (maximum particle size is no more than 50mm), send into roto-sifter again and carry out sorting, sub-elect 40mm, 5-40mm, less than three kinds of particle diameters of 5mm, partly send the continuation fragmentation back to greater than 40mm, 5-40mm partly adopts grinding method that secure bond thick, fine aggregate together separated, and obtains the clean stone of 5-25mm and less than the fine aggregate of 5mm; Carrying out superfine pulverizing less than the 5mm fine aggregate handles.Above-mentioned two kinds of recoverying and utilizing methods, though the stone in the discarded concrete, sand-cement slurry etc. are all recycled, energy consumption is big, recycles the cost height.

Summary of the invention:

The technical problem to be solved in the present invention provides a kind of method for recycling waste concrete, the recovery utilization rate height, and cost recovery is low.

The present invention is achieved through the following technical solutions:

A kind of method for recycling waste concrete comprises the following steps:

(1) discarded concrete is put into crusher and be crushed to particle diameter smaller or equal to 20mm, with impurity wherein: metal, wood, plastics are chosen, and then put into ball mill, 3-5% by its weight adds the concrete exciting agent simultaneously, is milled to specific surface area more than or equal to 390 square metres/every kilogram; Can contain discarded mortar in the described discarded concrete, the quantity that contains mortar is no more than 40% of gross weight;

(2) specific surface area that step (1) is obtained is mixed by following weight part proportioning with cement, medium coarse sand, 5-25mm rubble, water, concrete admixture more than or equal to 390 square metres/every kilogram regeneration Additive, the preparation regeneration concrete;

Regeneration Additive 80-120 part, cement 230-300 part, medium coarse sand 710-800 part, rubble 900-1200 part, water 160-200 part, concrete admixture 4-6 part.

Table 1:S95 breeze compares with regeneration Additive technical feature

Table 2 concrete performance contrast table

Annotate: C is that cement, KF are that breeze, FA flyash, WF are that regeneration Additive of the present invention, S medium coarse sand, G are that 5-25mm rubble, Ad are concrete admixture in the table.

The present invention compared with prior art has the following advantages:

One, the present invention comprises that with discarded concrete the mortar in the building waste all recycles, and through the pulvis after pulverizing, complete alternative breeze and flyash are used for concrete production.

Two, the present invention not only can reduce garbage discharge amount, saves the refuse treatment expense, reduces environmental pollution, and can effectively solve the contradiction between natural resources or disposable resource and the actual demand, meets industry policies such as national circulation Sustainable development.

Three, the present invention compared with prior art also has and recycles the advantage that cost is low, economic benefit is high.

Embodiment:

Embodiment 1

A kind of method for recycling waste concrete comprises the following steps:

(1) things such as the metal in the discarded concrete, wood, plastics is sorted away, put it into then and be crushed to particle diameter in the hammer mill smaller or equal to 20mm, to impurity wherein again: things such as metal, wood, plastics are chosen, and then put into ball mill, add the concrete exciting agent by 4% of its weight simultaneously, be milled to specific surface area more than or equal to 390 square metres/every kilogram; Contain 20% discarded mortar in the present embodiment in the discarded concrete.

(2) the particle diameter ratio surface-area that step (1) is obtained mixes by following weight part proportioning with cement, medium coarse sand, 5-25mm rubble, water, concrete admixture more than or equal to 390 square metres/every kilogram regeneration Additive, the preparation regeneration concrete;

90 parts of regeneration Additives, 250 parts of cement, 730 parts of medium coarse sands, 1000 parts of rubbles, 170 parts in water, 4.8 parts of concrete admixtures.

Embodiment 2

100 parts of regeneration Additives, 270 parts of cement, 765 parts of medium coarse sands, 1080 parts of rubbles, 185 parts in water, 5.2 parts of concrete admixtures.

All the other are implemented as embodiment 1.

Embodiment 3

110 parts of regeneration Additives, 290 parts of cement, 790 parts of medium coarse sands, 1150 parts of rubbles, 195 parts in water, 5.8 parts of concrete admixtures.

All the other are implemented as embodiment 1.

Claims

1. a discarded concrete recycling method is characterized in that comprising the following steps:

(1) discarded concrete (is contained mortar or brick or tile, or contain three's mixture) put into crusher and be crushed to particle diameter smaller or equal to 20mm, with impurity wherein: metal, wood, plastics are chosen, and then put into ball mill, 3-5% by its weight adds the concrete exciting agent simultaneously, is milled to specific surface area more than or equal to 390 square metres/every kilogram;

80～120 parts of regeneration Additives, 230～300 parts of cement, 710～800 parts of medium coarse sands, 900～1200 parts of rubbles, 160～200 parts in water, 4～6 parts of concrete admixtures.

2. a kind of discarded concrete recycling method as claimed in claim 1 is characterized in that: step (1) is put into the broken discarded concrete of crusher and is contained mortar.

3. a kind of discarded concrete recycling method as claimed in claim 1, it is characterized in that: step (1) is put into crusher with discarded concrete and is crushed to particle diameter smaller or equal to 20mm.