阅读说明：本技术 一种建筑垃圾再生细骨料的制备方法 (Preparation method of construction waste recycled fine aggregate ) 是由 胡文成 仲黎明 于 2020-08-11 设计创作，主要内容包括：本发明公开了一种建筑垃圾再生细骨料的制备方法,包括以下步骤：步骤一、材料筛选；步骤二、自然风干；步骤三、一次破碎；步骤四、一次磁选；步骤五、将二次破碎后未通过60-80目筛的建筑垃圾投放至螺旋分级机,分出再生细骨料；本发明通过在材料筛选时,将建筑垃圾投放至水池内,使用打捞机将木头、塑料打捞出,静置,使用机械犁搅动建筑垃圾,搅动完毕后,静置2-3min,二次打捞,配合在最终端,使用螺旋分级机分出再生细骨料,将再生细骨料内的泥块含量和微粉含量指标降低,表观密度有效提高,使得再生骨料的整体强度提高,压碎指标值低。(The invention discloses a preparation method of construction waste recycled fine aggregate, which comprises the following steps: step one, screening materials; step two, natural air drying; step three, primary crushing; step four, magnetic separation is carried out for the first time; fifthly, putting the construction waste which is not sieved by a 60-80 mesh sieve after secondary crushing into a spiral classifier, and separating out the recycled fine aggregate; according to the invention, when materials are screened, construction waste is put into a water tank, wood and plastic are fished out by using a fishing machine, the construction waste is kept stand, a mechanical plough is used for stirring the construction waste, the construction waste is kept stand for 2-3min after stirring is finished, secondary fishing is carried out, a spiral classifier is matched at the most terminal to separate out the regenerated fine aggregate, the mud block content and the micro powder content in the regenerated fine aggregate are reduced, the apparent density is effectively improved, the overall strength of the regenerated aggregate is improved, and the crushing index value is low.)

1. The preparation method of the construction waste recycled fine aggregate is characterized by comprising the following steps:

step one, material screening: transporting the construction waste to a screening place, putting the construction waste into a water pool through a feeding machine, standing for 2-3min, fishing out wood and plastic by using a fishing machine, standing for 30-45s, stirring the construction waste by using a mechanical plough, standing for 2-3min after stirring, and fishing for the second time;

step two, natural air drying: fishing out the screened construction waste, placing the construction waste on the ground, and naturally drying the construction waste;

step three, primary crushing: conveying the air-dried construction waste into a jaw crusher through a feeding machine, and screening the construction waste through a 6-8-mesh vibrating screen;

step four, primary magnetic separation: putting the crushed construction waste into a magnetic roller, and removing metals such as iron and steel in the construction waste;

step four, secondary crushing, namely putting the construction waste subjected to the primary magnetic separation into a jaw type fine crusher, and sieving the construction waste by a sieve of 60-80 meshes;

and step five, putting the construction waste which is not sieved by a 60-80 mesh sieve after secondary crushing into a spiral classifier, and separating the recycled fine aggregate.

2. The preparation method of the construction waste recycled fine aggregate according to claim 1, which is characterized by comprising the following steps: in the first step, the stirring mode of stirring the construction waste by using the mechanical plough is as follows: stirring was done from one side of the pool to the other, two times back and forth.

3. The preparation method of the construction waste recycled fine aggregate according to claim 1, which is characterized by comprising the following steps: in the second step, the natural air drying time of the construction waste is changed according to weather change, and is not less than eight hours.

4. The preparation method of the construction waste recycled fine aggregate according to claim 1, which is characterized by comprising the following steps: in the third step, the construction waste which is not screened out by the vibrating screen is put into the jaw crusher again for re-crushing, and the construction waste is screened by the vibrating screen with 10-15 meshes after the crushing is finished.

5. The preparation method of the construction waste recycled fine aggregate according to claim 1, which is characterized by comprising the following steps: in the fourth step, the magnetic field intensity of the magnetic roller is 1000-1200 GS, the rotating speed of the magnetic roller is 60-80 rpm, and the rolling time of the magnetic roller is 8-10 min.

6. The preparation method of the construction waste recycled fine aggregate according to claim 1, which is characterized by comprising the following steps: in the fifth step, the particle size of the recycled coarse aggregate is 9-30mm, the particle size of the recycled aggregate is 4.75-9mm, the particle size of the recycled fine aggregate is 1.35-4.75mm, and the particle size of the recycled fine powder is 0-1.35 mm.

7. The method for preparing the construction waste recycled fine aggregate according to claim 6, wherein the method comprises the following steps: before grading the recycled fine aggregate by a spiral classifier, adding a recycled aggregate modifier which accounts for 3-5% of the total weight of the recycled aggregate into the spiral classifier;

the recycled aggregate modifier comprises the following raw materials:

the raw materials comprise 9-11 wt% of slag micro powder slurry, 4-6 wt% of water glass solution, 9.5-10.5 wt% of PVA solution and the balance of water.

8. The method for preparing the construction waste recycled fine aggregate according to claim 7, wherein the method comprises the following steps: when the recycled aggregate modifier is prepared, firstly, water is added into a stirrer, then the slag micro powder slurry and the water glass solution are added into the water, the stirring time is 6-8 minutes, the stirring speed is 85-90 revolutions per minute, standing is carried out for 30-45 seconds, the stirring speed is adjusted to be 30-45 revolutions per minute, the PVA solution is added into the stirrer at the adding speed of 15-20g/min, and stirring is carried out for 8-10 minutes, so as to obtain the recycled aggregate modifier.

Technical Field

The invention relates to the technical field of building construction materials, in particular to a preparation method of building waste recycled fine aggregate.

Background

With the steady advance of the urbanization construction of China, many urban and rural buildings are dismantled, so a large amount of construction waste is generated. According to statistics, the construction waste generated in China per year exceeds 35 hundred million tons, accounts for 30-40% of the urban solid waste, and the utilization rate is less than 10%;

therefore, aiming at the situation that the recycled fine aggregate of the construction waste is generated timely, people begin to utilize the construction waste to prepare the recycled fine aggregate to replace high-quality natural aggregate, so that the cost is saved, and the resources are saved.

However, the existing recycled fine aggregate prepared by using construction waste has low structural strength and high crushing index which is usually about 20%, and the content of mud lumps and the content of micro powder in the recycled fine aggregate reach about 2% and 3%, respectively, so that the apparent density and strength of the recycled fine aggregate are seriously influenced, and the normal operation of construction is not facilitated.

Disclosure of Invention

The invention aims to provide a preparation method of recycled fine aggregate from construction waste, which aims to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a preparation method of construction waste recycled fine aggregate comprises the following steps:

step one, material screening: transporting the construction waste to a screening place, putting the construction waste into a water pool through a feeding machine, standing for 2-3min, fishing out wood and plastic by using a fishing machine, standing for 30-45s, stirring the construction waste by using a mechanical plough, standing for 2-3min after stirring, and fishing for the second time;

step two, natural air drying: fishing out the screened construction waste, placing the construction waste on the ground, and naturally drying the construction waste;

step three, primary crushing: conveying the air-dried construction waste into a jaw crusher through a feeding machine, and screening the construction waste through a 6-8-mesh vibrating screen;

step four, primary magnetic separation: putting the crushed construction waste into a magnetic roller, and removing metals such as iron and steel in the construction waste;

step four, secondary crushing, namely putting the construction waste subjected to the primary magnetic separation into a jaw type fine crusher, and sieving the construction waste by a sieve of 60-80 meshes;

and step five, putting the construction waste which is not sieved by a 60-80 mesh sieve after secondary crushing into a spiral classifier, and separating the recycled fine aggregate.

As further preferable in the present technical solution: in the first step, the stirring mode of stirring the construction waste by using the mechanical plough is as follows: stirring was done from one side of the pool to the other, two times back and forth.

As further preferable in the present technical solution: in the second step, the natural air drying time of the construction waste is changed according to weather change, and is not less than eight hours.

As further preferable in the present technical solution: in the third step, the construction waste which is not screened out by the vibrating screen is put into the jaw crusher again for re-crushing, and the construction waste is screened by the vibrating screen with 10-15 meshes after the crushing is finished.

As further preferable in the present technical solution: in the fourth step, the magnetic field intensity of the magnetic roller is 1000-1200 GS, the rotating speed of the magnetic roller is 60-80 rpm, and the rolling time of the magnetic roller is 8-10 min.

As further preferable in the present technical solution: in the fifth step, the particle size of the recycled coarse aggregate is 9-30mm, the particle size of the recycled aggregate is 4.75-9mm, the particle size of the recycled fine aggregate is 1.35-4.75mm, and the particle size of the recycled fine powder is 0-1.35 mm.

As further preferable in the present technical solution: before grading the recycled fine aggregate by a spiral classifier, adding a recycled aggregate modifier which accounts for 3-5% of the total weight of the recycled aggregate into the spiral classifier;

the recycled aggregate modifier comprises the following raw materials:

the raw materials comprise 9-11 wt% of slag micro powder slurry, 4-6 wt% of water glass solution, 9.5-10.5 wt% of PVA solution and the balance of water.

As further preferable in the present technical solution: when the recycled aggregate modifier is prepared, firstly, water is added into a stirrer, then the slag micro powder slurry and the water glass solution are added into the water, the stirring time is 6-8 minutes, the stirring speed is 85-90 revolutions per minute, standing is carried out for 30-45 seconds, the stirring speed is adjusted to be 30-45 revolutions per minute, the PVA solution is added into the stirrer at the adding speed of 15-20g/min, and stirring is carried out for 8-10 minutes, so as to obtain the recycled aggregate modifier.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, when materials are screened, construction waste is put into a water tank, wood and plastic are fished out by using a fishing machine, the construction waste is kept stand, a mechanical plough is used for stirring the construction waste, the construction waste is kept stand for 2-3min after stirring is finished, secondary fishing is carried out, a spiral classifier is matched at the most terminal to separate out the regenerated fine aggregate, the mud block content and the micro powder content in the regenerated fine aggregate are reduced, the apparent density is effectively improved, the overall strength of the regenerated aggregate is improved, and the crushing index value is low.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to data in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.