CN210231430U - Scouring sand production system and waste sand recycling system - Google Patents

Abstract

The utility model belongs to the technical field of sand casting, a regeneration recycling system who cleans sand production system and waste sand is provided. The utility model discloses a clean sand production system, include: a raw sand pretreatment system; scrubbing, desliming and magnetic separation system of raw sand: the device comprises a first scrubbing device, a first desliming device, a second scrubbing device, a second desliming device, a material separating device and a wet magnetic separation device which are connected in sequence; and the outlet of the raw sand pretreatment system is connected with the inlet of the first scrubbing equipment. The utility model discloses can carry out abundant desorption to the mud in the former sand, carry out abundant magnetic separation to the magnetic substance in the former sand, very big reduction the mud content and the magnetic separation material content of scrubbing sand, improved the silica content of scrubbing sand to simple process, production efficiency is high.

Description

Scouring sand production system and waste sand recycling system

Technical Field

The utility model belongs to the technical field of sand casting, concretely relates to clean regeneration recycling system of sand production system and waste sand.

Background

The scouring sand is raw sand for casting, and is generally raw sand for casting, which is obtained by scouring, washing, grading and other processes of natural silica sand, and has the mud content of less than 0.5 percent. The scouring sand is used in many applications, for example, in the production of coated sand for casting, and the specifications of the scouring sand for different applications are different.

With the rapid development of the foundry industry in China, the casting yield in China is always in the forefront of the world in recent years. Wherein, sand casting is the basic technology in casting production, and about 80-90% of castings are produced by adopting the sand casting technology. In one aspect, the raw materials used in sand casting include scouring sand, i.e., the sand casting process includes a production process of scouring sand. However, the scouring sand production system in the prior art cannot sufficiently remove the sludge in the raw sand, so that the obtained scouring sand has high sludge content and low silicon dioxide content, and simultaneously contains a certain amount of magnetic substances, thereby affecting the quality of the scouring sand.

On the other hand, a large amount of waste sand is generated in the production of castings. At present, except for recycling a small amount of waste sand, most of the waste sand is discharged as waste, so that resource waste and environmental pollution are caused. Thus, the reclamation of foundry waste sand is an important issue facing the foundry industry. Different regeneration processes can be selected according to different component compositions and characteristics of the waste foundry sand. Generally speaking, in the production process of waste sand regeneration, the selection of a regeneration method and the matching of equipment play a key role in the quality of the regenerated sand, the continuity and the smoothness of the production. However, in the system for recycling foundry waste sand in the prior art, the obtained reclaimed sand contains a certain amount of magnetic substances, the content of silicon dioxide is low, the mud content is high, the quality of the reclaimed sand is poor, and the quality of the reclaimed sand hardly meets the requirements of some castings.

In view of this, the utility model is especially provided.

SUMMERY OF THE UTILITY MODEL

A first object of the utility model is to provide a clean sand production system, this system can reduce the mud content of cleaning sand, reduces magnetic substance content, improves the silica content of cleaning sand, can overcome above-mentioned problem or solve above-mentioned technical problem at least partially.

A second object of the utility model is to provide a regeneration recycling system of useless sand, including foretell scouring sand production system, can reduce the mud content of reclaimed sand, reduce magnetic substance content, improve the silica content of reclaimed sand, guarantee the quality of reclaimed sand, can overcome above-mentioned problem or solve above-mentioned technical problem at least partially.

In order to achieve the above object, the utility model adopts the following technical scheme:

according to an aspect of the utility model, the utility model provides a clean sand production system, production system includes:

a raw sand pretreatment system;

scrubbing, desliming and magnetic separation system of raw sand: the device comprises a first scrubbing device, a first desliming device, a second scrubbing device, a second desliming device, a material separating device and a wet magnetic separation device which are connected in sequence; and the outlet of the raw sand pretreatment system is connected with the inlet of the first scrubbing equipment.

Furthermore, the raw sand scrubbing, desliming and magnetic separation system comprises a first scrubbing device, a first desliming device, a second scrubbing device, a second desliming device, a desliming hopper, a sand pump, a material distribution device and a wet magnetic separation device which are connected in sequence;

preferably, the first and second desliming apparatuses each independently comprise a screw desliming machine;

preferably, the second scrubbing device is a scrubbing unit consisting essentially of a plurality of scrubbing machines, preferably a scrubbing unit consisting essentially of 6-8 scrubbing machines;

preferably, the wet magnetic separation equipment comprises a wet cylinder type strong magnetic separator or a wet vertical ring type strong magnetic separator;

preferably, the raw sand pretreatment system comprises a first screening device, a size mixing device and a buffering bin which are sequentially connected, wherein an outlet of the buffering bin is connected with an inlet of a first scrubbing device;

preferably, the raw sand pretreatment system comprises a discharging device, a first screening device, a size mixing device, a sand pump and a buffer bin which are connected in sequence, wherein an outlet of the buffer bin is connected with an inlet of the first scrubbing device;

preferably, the first screening device comprises a linear vibrating screen;

preferably, the discharge apparatus comprises a discharge hopper with a hydraulic discharge pipe;

preferably, the magnetic separator further comprises an after-treatment system, wherein an inlet of the after-treatment system is connected with an outlet of the wet magnetic separation equipment;

preferably, the post-treatment system comprises a second screening device and a dewatering device, wherein an outlet of the second screening device is connected with an inlet of the dewatering device through a pipeline;

preferably, the second screening device comprises a linear vibration screening unit with a hydraulic sand washing device, and the linear vibration screening unit with the hydraulic sand washing device can screen scrubbing sand with various specifications, preferably at least four specifications;

preferably, the dewatering apparatus comprises a linear vibrating dewatering screen;

preferably, the scouring sand production system further comprises a sewage recovery treatment system, and the sewage recovery treatment system is connected with any one or more of the raw sand pretreatment system, the raw sand scouring, desliming and magnetic separation system or the post-treatment system;

preferably, the sewage recovery and treatment system comprises a sedimentation tank and a filter;

preferably, the sewage recovery and treatment system further comprises a sludge tank, a sludge scraping and sucking machine and a belt filter press.

According to another aspect of the utility model, the utility model provides a regeneration recycling system of waste sand, including foretell scouring sand production system.

Furthermore, the regeneration and reuse system also comprises a waste sand pretreatment system and a drying system;

preferably, the drying system comprises drying equipment, second magnetic separation equipment and third screening equipment which are connected in sequence;

preferably, the drying system comprises drying equipment, a buffer tank, second magnetic separation equipment, third screening equipment and a finished product tank which are connected in sequence;

preferably, the drying apparatus comprises a triple-pass dryer;

preferably, the second magnetic separation device comprises a strong magnetic separator;

preferably, the third screening device comprises a linear vibratory screening machine.

According to another aspect of the utility model, the utility model discloses still provide a clean sand production technology, including following step:

and sequentially carrying out primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material separation and wet magnetic separation on the pretreated raw sand.

Further, the pretreatment comprises: sequentially carrying out primary screening, size mixing and buffering on the raw sand;

preferably, the pre-treatment comprises: screening the raw sand by using first screening equipment, mixing the slurry by using slurry mixing equipment, and then entering a buffer bin for buffering;

preferably, the pre-treatment comprises: raw sand is discharged through a discharging device, then is screened through a first screening device, enters a size mixing device for size mixing, and is pumped into a buffer bin through a sand pump;

preferably, the first screening device comprises a linear vibrating screen;

preferably, the mass concentration of the mortar obtained by size mixing is 50-70%.

Further, the pretreated raw sand firstly enters first scrubbing equipment for first scrubbing, then enters first desliming equipment for first desliming, then enters second scrubbing equipment for second scrubbing, then enters second desliming equipment for second desliming, then enters material distribution equipment for material distribution, and then is subjected to magnetic separation through wet magnetic separation equipment;

preferably, the first and second desliming apparatuses each independently comprise a screw desliming machine;

preferably, the second scrubbing device is a scrubbing unit consisting essentially of a plurality of scrubbing machines, preferably a scrubbing unit consisting essentially of 6-8 scrubbing machines;

preferably, the time of the first scrubbing and the second scrubbing is 5-30min, preferably 6-20 min;

preferably, the wet magnetic separation equipment comprises a wet cylinder type strong magnetic separator or a wet vertical ring type strong magnetic separator.

Further, the method also comprises the following post-treatment: carrying out post-treatment on the raw sand subjected to wet magnetic separation to obtain scouring sand;

preferably, the post-processing comprises: screening and dehydrating for the second time;

preferably, the post-processing comprises: the raw sand subjected to wet magnetic separation enters second screening equipment for secondary screening, and the scrubbing sand subjected to secondary screening is conveyed to dewatering equipment through a pipeline for dewatering to obtain scrubbing sand;

preferably, the second screening device comprises a linear vibration screening unit with a hydraulic sand washing device, and the linear vibration screening unit with the hydraulic sand washing device can screen scrubbing sand with various specifications, preferably at least four specifications;

preferably, the dewatering apparatus comprises a linear vibrating dewatering screen.

Further, the method also comprises the following steps of sewage recovery treatment: carrying out recovery treatment on the sewage generated in any one or more steps of the pretreatment, the first scrubbing, the first desliming, the second scrubbing, the second desliming, material separation and wet magnetic selection;

preferably, the sewage generated in any one or more steps of the pretreatment, the first scrubbing, the first desliming, the second scrubbing, the second desliming, the material separation and the wet magnetic selection is conveyed to a sedimentation tank for sedimentation, and then is filtered by a filter to obtain reuse water for producing scrubbing sand;

preferably, the sludge generated by precipitation and/or filtration is subjected to concentration treatment, flocculation precipitation treatment and plate-and-frame filter pressing treatment to obtain a sludge cake.

According to another aspect of the utility model, the utility model provides a regeneration and reuse method of waste sand, comprising the above production process of scouring sand.

Further, the regeneration and reuse method comprises the following steps:

pretreating the waste sand to obtain pretreated waste sand; pretreating the pretreated waste sand, and sequentially performing primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material separation and wet magnetic separation.

Preferably, the regeneration and reuse method comprises the following steps:

(a) pretreatment of waste sand: pretreating the waste sand to obtain pretreated waste sand;

(b) pretreatment: pretreating the pretreated waste sand;

(c) scrubbing, desliming and magnetic separation: sequentially carrying out primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material distribution and wet magnetic separation on the pretreated waste sand;

(d) and (3) post-treatment: carrying out post-treatment on the waste sand subjected to wet magnetic separation to obtain scouring sand;

(e) and (3) drying: drying the obtained scrubbing sand to obtain reclaimed sand;

preferably, step (e) comprises: sequentially drying, carrying out magnetic separation for the second time and carrying out screening for the third time on the obtained scouring sand to obtain reclaimed sand;

preferably, step (e) comprises: the scouring sand enters drying equipment for drying treatment, then enters second magnetic separation equipment for second magnetic separation, and then enters third screening equipment for third screening to obtain reclaimed sand;

preferably, the temperature for drying is 300-400 ℃;

preferably, the drying apparatus comprises a triple-pass dryer;

preferably, the second magnetic separation device comprises a strong magnetic separator;

preferably, the third screening device comprises a linear vibratory screening machine.

Compared with the prior art, the beneficial effects of the utility model reside in that:

1. the utility model provides a clean sand production system, including former sand pretreatment system, the former sand clean, desliming and magnetic separation system, can carry out abundant desorption to the mud in the former sand, carry out abundant magnetic separation to the magnetic substance in the former sand, very big reduction the mud content of cleaning the sand, improved the silica content of cleaning the sand.

The content of magnetic substances can be obviously reduced through the wet magnetic separation equipment, the magnetic separation effect is better, the content of silicon dioxide in the scouring sand is obviously improved, and the quality of the obtained scouring sand is further ensured. And set up the branch material equipment before wet-type magnetic separation, can guarantee the stability and the homogeneity of wet-type magnetic separation's in-process material, provide reliable guarantee for going on smoothly of wet-type magnetic separation.

2. The utility model provides a regeneration recycling system of useless sand, including foretell scouring sand production system, therefore the mud content that has the reclaimed sand that obtains is low, and magnetic substance's content is low, and the high characteristics of silica's content have guaranteed the quality of reclaimed sand, are favorable to using the reclaimed sand that obtains to some special foundry goods like the higher foundry goods of production size precision requirement. The utilization value of the reclaimed sand is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic flow chart of a production process of scouring sand provided by the embodiment of the utility model;

fig. 2 is a schematic structural view of a scouring sand production system provided by an embodiment of the present invention;

fig. 3 is a schematic flow chart of a method for recycling waste sand provided by an embodiment of the present invention;

fig. 4 is a schematic structural view of a system for recycling waste sand provided by an embodiment of the present invention.

Icon: 100-a pretreatment system for waste sand; 200-a raw sand pretreatment system; 300-scouring, desliming and magnetic separation system of raw sand; 400-a post-treatment system; 500-a drying system;

1-waste sand discharge hopper; 2-magnetic separation belt conveyor; 3-vibrating a crushing screen; 4-a hoisting machine; 5-roughing screening machine; 6-finished product bin; 7-a magnetic separator; 8-a mechanical regenerator; 9-boiling dust removal bed; 10-a discharge hopper; 11-a linear vibrating screen; 12-a size mixing hopper; 13-a sand pump; 14-a surge bin; 15-a first scrubber; 16-a first screw desliming machine; 17-a scrubbing unit; 18-a second screw desliming machine; 19-a desliming bucket; 20-a sand pump; 21-a distributor; 22-wet type strong magnetic separator; 23-linear vibration screening machine combination; 24-linear vibrating dewatering screen; 25-three-pass dryer; 26-a linear vibrating screen classifier; 27-bucket elevator; 28-a buffer tank; 29-strong magnetic separator; 30-linear vibrating screen classifier; 31-bucket elevator; 32-finished product bucket.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to embodiments and examples, but those skilled in the art will understand that the following embodiments and examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. Those who do not specify the conditions are performed according to the conventional conditions or the conditions recommended by the manufacturer.

For overcoming the imperfection of the prior art, the utility model provides a clean regeneration recycling system of sand production system and useless sand to reduce the mud content in the sand of cleaning, the reclaimed sand that obtain, reduce magnetic substance's content, improve silicon dioxide's content, ensure the quality and the quality of product.

In a first aspect, there is provided in at least one embodiment a scouring sand production process comprising the steps of:

and sequentially carrying out primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material separation and wet magnetic separation on the pretreated raw sand.

The process can fully remove the sludge in the raw sand, fully magnetically separate the magnetic substances in the raw sand, greatly reduce the mud content of the scouring sand and improve the silicon dioxide content of the scouring sand.

Preferably, the scouring sand production process comprises the steps of:

(a) pre-treating raw sand;

(b) scrubbing, desliming and magnetic separation of raw sand: sequentially carrying out primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material separation and wet magnetic separation on the pretreated raw sand;

(c) and (3) post-treatment: and carrying out post-treatment on the raw sand subjected to wet magnetic separation to obtain the scouring sand.

According to the production process for scouring sand, the raw sand pretreatment process is arranged before the raw sand scouring, desliming and magnetic separation process, and impurities in the raw sand can be removed through the pretreatment process, so that the load of the subsequent scouring, desliming and magnetic separation process is reduced, the scouring effect and the scouring efficiency are improved, and the production efficiency is improved.

Above-mentioned scrub and wash sand production technology has set up the washing of former sand, desliming and magnetic separation process, including the first time that goes on in proper order scrub, desliming for the first time, scrub for the second time, desliming for the second time, divide material and wet-type magnetic separation, like this, can carry out abundant desorption to the mud in the former sand, carry out abundant magnetic separation to the magnetic substance in the former sand, improve the effect of scrubbing, very big reduction the mud content and the content of magnetic substance of scrub and wash the sand, improve the silica content of scrub and wash the sand.

Particularly, the wet magnetic separation step is arranged, so that the content of magnetic substances can be obviously reduced, the magnetic separation effect is better, the content of silicon dioxide in the scouring sand is obviously improved, and the quality of the obtained scouring sand is ensured. And the material distributing step is arranged before the wet magnetic separation, so that the stability and uniformity of the material in the wet magnetic separation process can be ensured, and the reliable guarantee is provided for the smooth wet magnetic separation.

Furthermore, a post-treatment process is arranged after the processes of scrubbing, desliming and magnetic separation of the raw sand, and the scrubbing sand with target specification or meeting the production requirement can be obtained through post-treatment.

Tests show that the scrubbing sand obtained by the production process of the scrubbing sand of the utility model has the mud content ranging from 0.15 to 0.3 percent (mass content), the magnetic substance content ranging from 0.3 to 1.5 percent (mass content) and the silicon dioxide content ranging from 88 to 96 percent (mass content).

It should be noted that:

unless otherwise defined, technical and scientific terms used herein have the same meaning as is familiar to those skilled in the art.

In the present invention, all the technical features mentioned herein and preferred features may be combined with each other to form a new technical solution, if not specifically stated.

Herein, unless otherwise stated, the individual operational steps may or may not be performed sequentially. For example, other steps may be included between the various operational steps, and the order may be reversed between the various steps. Preferably, the steps herein are performed sequentially.

Unless otherwise indicated, the terms and definitions set forth herein apply to the terms as they are commonly used in the art. Specifically, the related art terminology is explained as follows:

raw sand: also referred to as new sand, generally refers to foundry sand that was first used. The utility model discloses in, former sand can be for the foundry sand of first use, also can be for the sand that useless sand obtains through the preliminary treatment back. For example, in a method for recycling waste sand, raw sand is sand obtained by pretreating waste sand; that is to say, in the utility model discloses, the waste sand of preliminary treatment also can be called former sand. For another example, in the production process of the scouring sand, the raw sand may be natural quartz sand (silica sand), or may be sand obtained by pretreating waste sand.

It can be understood that the utility model discloses a wash the difference of sand production technology and the regeneration and reuse method of useless sand mainly lies in, and the raw materials sand that adopts is different, and in the regeneration and reuse method of useless sand, the raw materials sand that adopts need carry out the preliminary treatment to useless sand for useless sand, then carry out the preliminary treatment again, clean for the first time, desliming for the first time, clean for the second time, desliming for the second time, divide processes such as material and wet-type magnetic separation.

Waste sand: also known as used sand, the main solid waste produced during the production of castings. Typically, the surface of the spent sand particles will have a coating of a failed or non-failed binder or other contaminants attached to it.

Reclaimed sand: the waste sand is subjected to regeneration treatment to remove or partially remove impurities such as residual binder and the like in the sand grains, and the sand with the performance close to that of new sand is recovered.

The mud content: the mass of particles with the particle size of less than 0.02mm in the foundry sand accounts for the percentage of the total mass of the sand sample.

Magnetic separation: separating different magnetic substances from the mixture according to the different magnetism of the substances; the method comprises dry magnetic separation and wet magnetic separation, wherein the wet magnetic separation can be used for separating ferromagnetic substances.

In a second aspect, there is provided in at least one embodiment a scrub sand production system, the production system comprising:

a raw sand pretreatment system;

scrubbing, desliming and magnetic separation system of raw sand: the device comprises a first scrubbing device, a first desliming device, a second scrubbing device, a second desliming device, a material separating device and a wet magnetic separation device which are connected in sequence; an outlet of the raw sand pretreatment system is connected with an inlet of the first scrubbing equipment;

a post-processing system: and the inlet of the post-treatment system is connected with the outlet of the wet magnetic separation equipment.

It will be appreciated that the above-described scrub sand production system corresponds to the above-described scrub sand production process, i.e. the scrub sand production system is a system (apparatus) applied to the scrub sand production process. This clean sand production system and foretell clean sand production technology is based on same utility model design, therefore has at least and cleans the same advantage of sand production technology with the aforesaid, the utility model discloses no longer describe herein.

Specifically, according to the utility model discloses an embodiment, the production process that will scrub the scouring sand can be divided into three regions, including the pretreatment district, scrub, desliming and magnetic separation district to and aftertreatment district. The above-described scouring sand production process and production system are described in detail below.

(a) Pretreatment of raw sand

In the step, the raw sand is sequentially subjected to primary screening, size mixing and buffering.

According to an embodiment of the present invention, step (a) comprises: the raw sand is discharged through the discharging device, then is screened through the first screening device, enters the size mixing device for size mixing, and is pumped into the buffer bin through the sand pump.

In the pretreatment process of the raw sand, the adopted equipment comprises unloading equipment, first screening equipment, size mixing equipment, a sand pump and a buffer bin. The outlet of the discharging device is connected with the inlet of the first screening device, the outlet of the first screening device is connected with the inlet of the size mixing device, the outlet of the size mixing device is connected with the inlet of the sand pump, and the outlet of the sand pump is connected with the inlet of the buffer bin.

Preferably, the discharge apparatus comprises a discharge hopper (discharge hopper) with a hydraulic discharge pipe;

preferably, the first screening device comprises a linear vibrating screen;

preferably, the size mixing equipment comprises a size mixing hopper;

preferably, the mass concentration of the mortar obtained by mixing is 50-70%, and can be, for example, 50%, 52%, 55%, 58%, 60%, 62%, 65%, 68% or 70% typically but not limitatively. The mortar concentration in the range is more beneficial to subsequent operation and more meets the production requirement.

The equipment used in the pretreatment in step (a), such as the discharging equipment, the first screening equipment, the size mixing equipment and the like, can adopt the common equipment in the field. Preferably, the equipment adopted in the raw sand pretreatment process comprises a discharge hopper with a hydraulic discharge pipe, a linear vibrating screen, a slurry mixing hopper, a sand pump and a mortar buffering bin. Wherein, the bottom of hopper is former sand discharge port down, and hopper lateral wall distributes has water conservancy discharge tube down, and former sand discharge port below is equipped with linear vibrating screen, and impurity and large granule material are discharged to the screen surface on the linear vibrating screen, and the fine particle material in the sand is sieved away to the screen surface under the linear vibrating screen, and middle screen surface is required material, and middle screen surface is linked together with the size mixing fill, and the size mixing fill is linked together with the sand pump, and through the size mixing fill size mixing back, the sand pump is carried the mortar to the surge bin and is stored.

From this, according to the utility model discloses an embodiment, former sand is unloaded through the discharge hopper in the preceding processing area, then passes through the impurity that rectilinear vibrating screen detached in the former sand again, reentrants the size mixing fill pump after size mixing go into the surge bin through the sand pump. Like this, can get rid of some impurity in the former sand, separate out large granule impurity etc. in the former sand, carry out preliminary screening to the former sand to adjust the concentration of mortar to suitable within range, thereby can alleviate the follow-up load of cleaning, desliming and magnetic separation process, improve and clean the effect and clean efficiency, and then improve production efficiency.

(b) Scouring, desliming and magnetic separation of raw sand

In the step, the pretreated raw sand is sequentially subjected to primary scrubbing, primary desliming, secondary scrubbing, secondary desliming, material separation and wet magnetic separation.

According to an embodiment of the present invention, step (b) comprises: the method comprises the steps that pretreated raw sand firstly enters first scrubbing equipment to be scrubbed for the first time, then enters first desliming equipment to be desliming for the first time, then enters second scrubbing equipment to be scrubbed for the second time, then enters second desliming equipment to be desliming for the second time, then enters a desliming hopper to be settled and desliming, the raw sand obtained through settlement and desliming is pumped into material distribution equipment through a sand pump, and then is magnetically separated through wet magnetic separation equipment.

In the working procedures of scrubbing, desliming and magnetic separation of the raw sand, the adopted equipment comprises first scrubbing equipment, first desliming equipment, second scrubbing equipment, second desliming equipment, a desliming hopper, a sand pump, material distribution equipment and wet magnetic separation equipment. The inlet of the first scrubbing device is connected with the outlet of the buffer bin, the outlet of the first scrubbing device is connected with the inlet of the first desliming device, the outlet of the first desliming device is connected with the inlet of the second scrubbing device, the outlet of the second scrubbing device is connected with the inlet of the second desliming device, the outlet of the second desliming device is connected with the inlet of the desliming hopper, the outlet of the desliming hopper is connected with the inlet of the sand pump, the outlet of the sand pump is connected with the inlet of the distributing device, and the outlet of the distributing device is connected with the inlet of the wet magnetic separation device.

Preferably, the first scrubbing apparatus is a scrubbing machine commonly used in the art. The first scrubbing is coarse scrubbing and can be done using a scrubbing machine commonly used in the art.

Preferably, the second scrubbing apparatus comprises a scrubbing unit comprising a plurality of scrubbing machines, preferably a scrubbing unit comprising 6-8 scrubbing machines, more preferably a scrubbing unit comprising 7 scrubbing machines. The second scrubbing is fine scrubbing, preferably a combined scrubbing machine is used for scrubbing, so that the material to be scrubbed can be strongly scrubbed, impurities on the surface are removed, and the scrubbing qualification rate is improved.

Preferably, the first desliming device is a first screw desliming machine; the second desliming device is a first spiral desliming machine. The first desliming is coarse desliming, the second desliming is fine desliming, and the two-time desliming equipment can be a spiral desliming machine, so that the desliming effect and the desliming efficiency can be improved.

Preferably, the time of the first scrubbing and the second scrubbing is 5-30min, preferably 6-20 min; for example, the time for the first scrubbing is 5-30min, and the time for the second scrubbing is 5-30min, and may be, for example, 5min, 6min, 8min, 10min, 12min, 15min, 20min, 22min, 25min, or 30min, which is typical but not limiting. The appropriate scrubbing time helps to ensure the scrubbing effect and improve the scrubbing efficiency.

Preferably, the rotating speed of the first scrubbing equipment and the rotating speed of the second scrubbing equipment are respectively and independently 250-350 r/min; for example, the rotation speed of the first scrubbing device is 250-350r/min, and the rotation speed of the second scrubbing device is 250-350r/min, and typically but not limited to, 250r/min, 260r/min, 270r/min, 280r/min, 290r/min, 300r/min, 310r/min, 320r/min, 330r/min, 340r/min or 350 r/min. The proper rotation speed of the scrubbing machine is helpful to ensure the scrubbing effect and improve the scrubbing efficiency.

Through the cooperation of rough scrubbing, rough desliming, fine scrubbing and fine desliming, the method is favorable for reducing impurities on the surface of the raw sand, scrubs the impurities, fully removes the sludge in the raw sand, ensures the quality of the obtained scrubbed sand, and improves the production efficiency.

Preferably, the material dividing device may be a material divider commonly used in the art.

Preferably, the wet magnetic separation equipment comprises a wet cylinder type strong magnetic separator or a wet vertical ring type strong magnetic separator.

The wet type cylinder type strong magnetic separator or the wet type vertical ring strong magnetic separator is suitable for separating strong magnetic substances, has high magnetic separation efficiency and good magnetic separation effect, can obviously reduce the content of the magnetic substances, obviously improves the content of silicon dioxide in the scouring sand, and further ensures the quality of the obtained scouring sand. And the distributor is used for distributing materials before entering the wet magnetic separation equipment, so that the stability and uniformity of the materials in the wet magnetic separation process can be ensured, and the reliable guarantee is provided for the smooth wet magnetic separation.

The equipment used in the scouring, desliming and magnetic selection of the raw sand in the step (b) can adopt the equipment commonly used in the field, such as a scouring machine, a distributor and the like. Preferably, the equipment adopted in the working procedures of scrubbing, desliming and magnetic separation of the raw sand comprises a first scrubbing machine, a first spiral desliming machine, a scrubbing unit, a second spiral desliming machine, a desliming hopper, a sand pump, a distributor and a wet-type strong magnetic separator. The first scrubbing machine is connected with the first spiral desliming machine and has the functions of coarse scrubbing and coarse desliming for raw sand; the scrubbing unit is connected with a second spiral desliming machine and plays a role in fine scrubbing and fine desliming, the scrubbing unit is formed by combining a plurality of scrubbing machines in a series connection mode, each scrubbing machine is composed of a hexagonal cylinder and stirring blades, an inlet is positioned below the outer side of the hexagonal cylinder of each scrubbing machine, an outlet is positioned above the opposite side of the inlet, each stirring blade is divided into an upper layer, a middle layer and a lower layer, the blades of the three layers are positioned on the same stirring shaft, the upper layer blade and the lower layer blade have certain angles, the angles of the upper layer blade and the lower layer blade are opposite, the upper layer blade exerts downward acting force on mortar, the lower layer blade exerts upward acting force on mortar, and the middle blade plays a role in horizontal stirring; the material outlet of the scrubbing unit is connected with the inlet of a second spiral deslimer, the material outlet of the second spiral deslimer is connected with the inlet of a deslimer hopper, the outlet of the deslimer hopper is connected with the inlet of a sand pump, the material outlet of the sand pump is connected with the material inlet of a distributor through a pipeline, the outlet of the distributor is connected with the inlet of a wet-type strong magnetic separator, and the magnetically separated materials enter a subsequent post-treatment process.

From this, according to the utility model discloses an embodiment, the former sand through the pretreatment is cleaning, desliming and magnetic separation, at first get into first platform through the surge bin and clean the machine and carry out the coarse cleaning, then get into first spiral desliming machine and carry out desliming for the first time, get into the combination afterwards and clean the machine (clean the unit) and carry out 7 times the essence and clean, the former sand that cleans through the essence gets into second spiral desliming machine again and carries out desliming for the second time, then get into and take off the mud fill and subside the desliming, go into the tripper with former sand pump again through the sand pump, select most magnetic substance through choice wet magnetic separator at last. And then the sludge in the raw sand is fully removed, the magnetic substances in the raw sand are fully magnetically separated, the sludge content and the magnetic substance content of the scouring sand are greatly reduced, the silicon dioxide content of the scouring sand is improved, and the quality of the scouring sand is ensured.

(c) Post-treatment

In the step, the raw sand subjected to wet magnetic separation is subjected to post-treatment to obtain scouring sand.

According to an embodiment of the present invention, step (c) comprises: screening and dehydrating for the second time; further, step (c) comprises: and (3) enabling the raw sand subjected to wet magnetic separation to enter second screening equipment for secondary screening and further desliming, and conveying the scrubbing sand subjected to secondary screening to dewatering equipment through a pipeline for dewatering to obtain the scrubbing sand.

In the post-treatment process of the raw sand, the adopted equipment comprises second screening equipment and dewatering equipment. The inlet of the second screening device is connected with the outlet of the wet magnetic separation device, and the outlet of the second screening device is connected with the inlet of the dewatering device through a pipeline.

Preferably, the second screening device comprises a linear vibration screening machine set with a hydraulic sand washing device, and the linear vibration screening machine set with the hydraulic sand washing device can screen scrubbing sand with various specifications, and preferably screen scrubbing sand with at least four specifications.

The utility model discloses in, the screening unit has been adopted to the second screening equipment, like this, the sand of cleaning of four kind at least specifications can be sieved out in one shot production, and the sand of cleaning of different specifications can adjust its particle size distribution wantonly, very big improvement production efficiency.

Preferably, the dewatering apparatus comprises a linear vibrating dewatering screen.

Preferably, the resulting scouring sand has a particle size in the range of 20 to 200 mesh. The particle size of the scouring sand can be adjusted according to the actual production requirement.

The equipment used in the post-treatment of the raw sand in the step (c), such as dewatering equipment, can be equipment commonly used in the art. Preferably, the equipment adopted for the post-treatment of the raw sand comprises a linear vibration screening machine combination with a hydraulic sand washing device and a linear vibration dewatering screen; the hydraulic sand washing device is arranged above the linear vibrating screen, consists of a plurality of water pipes with a plurality of holes on the pipe walls, and washes sand on the screen surface; the vibrating screen classifier is divided into four to five layers, each layer of the sieve is screened to separate scrubbing sand with different granularities and is conveyed to a dewatering sieve through a pipeline, the lowest layer is a sewage recovery device, and sewage with mud is collected and conveyed to a sewage recycling process; the dewatering screen is a layer of upper screen surface which is scouring sand, the screen is provided with a sewage recovery device, and the removed sewage is conveyed to a sewage treatment and recycling process through the sewage recovery device; the screening unit is two screens for relay screening, the first layer of the first screen is directly conveyed to the sand warehouse, the second layer of the first screen corresponds to the first layer of the second screen, the third layer of the first screen corresponds to the second layer of the second screen, and the rest can be done as required.

The utility model discloses in, the grit that has scrubbed utilizes water to carry to the storehouse through the pipeline, adopts the dewatering screen to dewater the grit, retrieves water to sewage treatment system again, like this, can reduce belt transport, reduces the input cost.

From this, according to the utility model discloses an embodiment, former sand gets into rectilinear vibration screening unit and carries out the particle size screening and further desliming after the aforesaid is cleaned desliming magnetic separation, and the sand of cleaning after the screening is through pipeline transport to dewatering screen and carry out dehydration treatment, obtains after dehydration treatment to clean sand and get into the sand storehouse and store. Therefore, the scrubbing sand with target specification or meeting production requirement can be screened out by one-time production, the particle size distribution of the scrubbing sand with different specifications can be adjusted at will, and the production efficiency is greatly improved.

According to the utility model discloses an embodiment, above-mentioned sand scrubbing production technology still includes: recycling the sewage generated in any one or more of the steps (a), (b) and (c); that is, the wastewater produced in the step (a) may be subjected to a recovery treatment, the wastewater produced in the step (b) may be subjected to a recovery treatment, the wastewater produced in the step (c) may be subjected to a recovery treatment, the wastewater produced in the step (a) and the step (b) may be subjected to a recovery treatment, the wastewater produced in the step (b) and the step (c) may be subjected to a recovery treatment, or the wastewater produced in the step (a), the step (b) and the step (c) may be subjected to a recovery treatment. Preferably, all the sewage generated in the scouring sand production process is recycled, that is, the sewage generated in the above step (a), step (b) and step (c) is recycled.

Preferably, the sewage generated in the production process is firstly conveyed into a sedimentation tank for sedimentation and then filtered by a filter to obtain the reuse water which can be used for scouring sand production.

Preferably, the sludge generated by precipitation and/or filtration is subjected to concentration treatment, flocculation precipitation treatment and plate-and-frame filter pressing treatment to obtain a sludge cake. That is, the sludge produced by the precipitation can be subjected to concentration treatment, flocculation precipitation treatment and plate-and-frame filter pressing treatment, the sludge produced by the filtration can be subjected to concentration treatment, flocculation precipitation treatment and plate-and-frame filter pressing treatment, and the sludge produced by the precipitation and filtration can also be subjected to concentration treatment, flocculation precipitation treatment and plate-and-frame filter pressing treatment.

The utility model discloses in, handle and the retrieval and utilization with the sewage that each process produced, great improvement water resource utilization ratio, guaranteed effective utilization of sewage, mud, the environmental protection is energy-conserving pollution-free.

The equipment adopted by the sewage recovery treatment comprises a sedimentation tank, a sludge tank, a filter, a sludge scraping and sucking machine and a belt type filter press.

The above-mentioned equipment used in the sewage recovery treatment, such as a settling tank, a filter, etc., may be equipment commonly used in the art. Preferably, the sedimentation tank consists of a plurality of sedimentation tanks, the sedimentation modes comprise natural sedimentation and flocculation sedimentation, the sewage is naturally sedimentated through the sedimentation tank after being recovered, then the sludge after the natural sedimentation is collected through a walking sludge scraping and sucking machine, then the sludge is further sedimentated by adding a flocculating agent, then the sedimentated sludge is subjected to pressure filtration through a belt type pressure filter to fully separate the sludge from the water, so that the sludge with lower water content and the water with lower sludge content are obtained, and the water is filtered through a filter to finally obtain purer water for the whole scouring sand production; the sludge scraping and sucking machine is provided with a track, the track is positioned on the wall of the sedimentation tank, the sludge scraping and sucking machine stretches over the sedimentation tank and travels on the track at regular time, the sludge scraping and sucking machine is provided with a plurality of pump suction pipes, the pump suction pipes vertically penetrate into the bottom of the sedimentation tank, and the pump suction pipes suck sludge at the bottom of the sedimentation tank into a sludge tank for centralized sedimentation along with the traveling of the sludge scraping and sucking machine; the flocculating agent is added into the sludge tank in proportion through a dosing device, and the flocculated and precipitated sludge is pumped to a belt filter press through a sludge pump for filter pressing treatment, so that the sludge and the water are fully separated finally.

The sewage generated in the production process of the scouring sand is treated and recycled, so that the production water for scouring is recycled, the water resource utilization rate is improved, the problem of water resource waste is relieved, the water burden of enterprises is reduced, and the scouring sand is environment-friendly, energy-saving and pollution-free.

From this, according to the utility model discloses an embodiment, produced sewage is all retrieved to the sedimentation tank in whole production process, and the filtration through sedimentation tank, filter obtains the reuse water that can be used to scrub sand production, deposits, filters produced mud and through sludge concentration processing, flocculation and precipitation processing, plate frame filter-pressing processing, finally obtains the lower sludge cake of water content, as building brick raw materials.

The scouring sand production process is simple in process, easy to operate, good in controllability and low in cost, the prepared scouring sand is excellent in quality, sewage in the scouring sand production process is treated and recycled, water waste is reduced, the problem of serious water resource waste is solved, water consumption burden of enterprises is reduced, and industrial production is facilitated.

In a third aspect, in at least one embodiment, a method for recycling waste sand is provided, which comprises the above scouring sand production process.

In a fourth aspect, in at least one embodiment, a system for recycling waste sand is provided, which comprises the above-mentioned scouring sand production system.

It can be understood that the above system for recycling waste sand corresponds to the above method for recycling waste sand, that is, the system for recycling waste sand is a system (device) applied to the method for recycling waste sand.

This regeneration and reuse method and system of useless sand and foretell sand scrubbing production technology and system are based on same utility model and conceive, therefore have at least and scrub the same advantage of sand scrubbing production technology and system with the aforesaid, the utility model discloses no longer describe herein.

The utility model discloses in, the regeneration and reuse method of waste sand includes aforementioned sand scrubbing production technology, still includes the preliminary treatment process and the drying process to waste sand. Namely, the waste sand is pretreated to obtain pretreated waste sand, the obtained pretreated waste sand is sequentially subjected to pretreatment, scrubbing, desliming, magnetic separation and aftertreatment to obtain scrubbed sand, and finally the scrubbed sand is dried to obtain reclaimed sand.

Specifically, according to the utility model discloses an embodiment, can divide into five regions with the regeneration retrieval and utilization process of waste sand, including the preliminary treatment district of waste sand, the pretreatment district cleans, desliming and magnetic separation district, aftertreatment district to and drying zone. The method and system for reclaiming and reusing the waste sand are described in detail below.

Pretreatment of S1 waste sand

In the step, the waste sand is pretreated to obtain pretreated waste sand.

It should be noted that the present invention does not have any special limitation on the specific operation mode of the pretreatment of the waste sand and the adopted equipment, and the pretreatment can be performed with reference to the prior art, and the present invention is not described in detail herein.

Typically but not by way of limitation, the waste sand may be discharged from a waste sand discharge hopper, passed through a magnetic separation belt conveyor, fed into a vibrating crushing screen, fed into a lifter, sieved and roughly separated, fed into a finished product bin, and fed into a magnetic separator, a mechanical regenerator and a boiling dust removal bed in sequence, so as to pretreat the waste sand.

Through carrying out preliminary treatment to the waste sand, can get rid of most miropowder, mud branch class impurity on waste sand surface, through carrying out the breakage to the sand block, can also isolate iron plate, iron fillings, stone, rubbish, large granule impurity etc. in the waste sand to obtain preliminary treatment waste sand.

Pretreatment of S2

S3 scrubbing, desliming and magnetic separation

S4 post-processing

It is understood that the foregoing pre-treatment of the raw sand in step (a), scouring, desliming and magnetic separation of the raw sand in step (b) and post-treatment in step (c) are applicable to the pre-treatment in S2, scouring in S3, desliming and magnetic separation and post-treatment in S4, that is, the explanation of the pre-treatment in S2, scouring in S3, desliming and magnetic separation and post-treatment in S4 can refer to the explanation of steps (a), (b) and (c) in the foregoing, and will not be repeated herein.

S5 drying

In this step, the obtained scouring sand is dried to obtain reclaimed sand.

According to the utility model discloses an embodiment, S5 is dry includes: and sequentially drying, carrying out secondary magnetic separation and tertiary screening on the obtained scouring sand to obtain reclaimed sand.

Preferably, the S5 drying comprises: the scrubbing sand firstly enters drying equipment for drying treatment, then enters a buffer tank for storage, then enters second magnetic separation equipment for second magnetic separation, and then is screened for the third time in third screening equipment to obtain reclaimed sand.

In the drying procedure, the adopted equipment comprises drying equipment, a buffer tank (storage tank), magnetic separation equipment, third screening equipment and a finished product tank (dried sand storage tank); wherein, the export of drying equipment and the entry linkage of buffer tank, the export of buffer tank and the entry linkage of magnetic separation equipment, the export of magnetic separation equipment and the entry linkage of third screening equipment, the export and the finished product storage tank of third screening equipment are connected.

Preferably, the drying apparatus comprises a triple-pass dryer.

Preferably, the temperature for drying is 300-400 ℃; typically, but not limitatively, the temperature of drying may be, for example, 300 ℃, 310 ℃, 320 ℃, 330 ℃, 340 ℃, 350 ℃, 360 ℃, 370 ℃, 380 ℃, 390 ℃ or 400 ℃.

The utility model discloses in, adopt three return stroke drying-machines to dry, have compact structure, area is little, safe, reliable, the energy consumption is low, the effectual characteristics of material stoving realize automated control easily, help realizing reducing energy consumption and reduce cost's effect.

Preferably, the second magnetic separation device comprises a strong magnetic separator; the second magnetic separation is dry magnetic separation, and the adopted equipment can be a dry strong magnetic separator commonly used in the prior art. The content of magnetic substances in the reclaimed sand can be further reduced through the arrangement of the second magnetic separation equipment, the regeneration effect is improved, and the performance index of the obtained reclaimed sand is excellent.

Preferably, the third screening device comprises a linear vibratory screening machine.

The equipment used in the above drying process, such as magnetic separation equipment, third screening equipment, etc., can adopt the equipment commonly used in the art. Preferably, the equipment adopted in the drying procedure comprises a three-pass dryer, a bucket elevator, a linear vibration screening machine, a strong magnetic separator, a cyclone dust collector, a desulfurizing tower, a screw feeder, an induced draft fan, a buffer tank and a finished product material tank; wherein, the outlet of the sand scrubbing hopper is connected with the inlet of the screw feeder, the outlet of the screw feeder corresponds to the inlet of the bucket elevator, and the material outlet of the bucket elevator corresponds to the inlet of the three-pass drying furnace; the outlet of the three-pass drying furnace corresponds to the inlet of the bucket elevator, the inlet of the bucket elevator is connected with the inlet of the buffer tank, a strong magnetic separator is arranged below the buffer tank, magnetic substances in sand are further separated, the outlet of the strong magnetic separator corresponds to the inlet of the linear vibrating screen, the outlet of the linear vibrating screen separator corresponds to the inlet of the bucket elevator, the outlet of the bucket elevator is connected with the inlet of a finished product material tank, the tail gas outlet of the drying furnace is connected with a cyclone dust collector, and the cyclone dust collector is connected with a draught fan.

From this, according to the utility model discloses an embodiment, the sand that cleans after the screening gets into the drying furnace and carries out drying process, removes the moisture in the sand, and the sand after drying process gets into the buffer tank and stores, passes through the further magnetic separation of remaining magnetic material in the strong magnet separator with the sand again, then gets into the rectilinear vibration screening machine and sieves the processing, impurity and coarse particle material and miropowder in the desanding, get into stoving sand storage tank at last and store.

The reclaimed sand obtained by the method can be used for producing precoated sand, resin sand and the like. The utility model discloses the mud content of the reclaimed sand that obtains is low, and magnetic substance content is low, and the content of silica is high, and the quality of reclaimed sand can obtain guaranteeing, and the performance is excellent, consequently, the utility model discloses a reclaimed sand can be arranged in making the higher complicated foundry goods of precision, for example on the relevant casting of engine.

It should be understood that the above-mentioned processes and systems for producing scouring sand, and the methods and systems for reclaiming and recycling waste sand, which are not described in detail in the description, are all common parameters, conventional operation modes or common equipment, such as operation parameters of sieving, etc., which are easily conceived by those skilled in the art, and reference may be made to the prior art or the operation may be adjusted by those skilled in the art according to the actual situation, so that detailed description thereof may be omitted.

In order to facilitate understanding of the present invention, the present invention will be further described with reference to the following embodiments, comparative examples and drawings.

Example 1

1. Referring to fig. 1, a process for producing scouring sand includes the steps of:

(a) pretreatment of raw sand

The raw sand is discharged through a discharge hopper in the pretreatment area, then impurities in the raw sand are removed through a linear vibrating screen, and the raw sand enters a size mixing hopper for size mixing and is pumped into a buffer bin through a sand pump. Wherein the mass concentration of the mortar obtained by size mixing is 50-70%.

(b) Scouring, desliming and magnetic separation of raw sand

The pre-treated raw sand firstly enters a first scrubbing machine for rough scrubbing through a buffer bin in scrubbing, desliming and magnetic separation, then enters a first spiral desliming machine for first desliming, then enters a combined scrubbing machine (scrubbing unit) for fine scrubbing for 7 times, and then enters a second spiral desliming machine for second desliming, then enters a desliming hopper for settlement desliming, and then is pumped into a distributor through a sand pump, and finally most of magnetic substances are selected through a wet type concentration magnetic separator. Wherein the coarse scrubbing time is 6-20min, and the fine scrubbing time is 6-20 min; the rotation speed of the scrubbing machine in the rough scrubbing and the fine scrubbing is 250-350 r/min.

(c) Post-treatment

And after being subjected to scrubbing, desliming and magnetic separation, the raw sand enters a linear vibration screening unit for granularity screening and further desliming, the screened scrubbing sand is conveyed to a dewatering screen through a pipeline for dewatering treatment, and the scrubbing sand is obtained after the dewatering treatment and enters a sand warehouse for storage. The particle size range of the obtained scouring sand is 20-200 meshes.

And (c) recycling all the sewage generated in the steps (a), (b) and (c), namely the sewage generated in the whole production process into a sedimentation tank, obtaining reuse water for scouring sand production through sedimentation in the sedimentation tank and filtration of a filter, and finally obtaining sludge cakes with lower water content through sludge concentration treatment, flocculation precipitation treatment and plate and frame filter pressing treatment on the sludge generated by sedimentation and filtration, wherein the sludge cakes are used as building brick raw materials.

2. Referring to fig. 2, a scouring sand production system includes: a raw sand pre-treatment system 200, a raw sand scrubbing, desliming and magnetic separation system 300, a post-treatment system 400, and a sewage recovery treatment system (not shown).

The equipment adopted in the raw sand pretreatment process comprises a discharge hopper 10 with a hydraulic discharge pipe, a linear vibrating screen 11, a size mixing hopper 12, a sand pump 13 and a mortar buffer bin 14. Wherein, the bottom of discharge hopper is former sand discharge port, the discharge hopper lateral wall distributes has water conservancy discharge tube, former sand discharge port below is equipped with linear vibrating screen 11, 11 upper screen surfaces of linear vibrating screen discharge impurity and large granule material, 11 lower screen surfaces of linear vibrating screen sieve go out the fine particle material screening in the sand, middle screen surface is required material, middle screen surface is linked together with size mixing hopper 12, size mixing hopper 12 is linked together with sand pump 13, behind the size mixing of size mixing hopper 12, sand pump 13 carries the mortar to surge bin 14 and stores.

The equipment adopted in the working procedures of scrubbing, desliming and magnetic separation of the crude sand comprises a first scrubbing machine 15, a first spiral desliming machine 16, a scrubbing unit 17, a second spiral desliming machine 18, a desliming hopper 19, a sand pump 20, a distributor 21 and a wet-type strong magnetic separator 22. Wherein, the first scrubbing machine 15 is connected with the first spiral desliming machine 16 and has the functions of coarse scrubbing and coarse desliming for the raw sand; the scrubbing unit 17 is connected with a second spiral desliming machine 18 and plays a role in fine scrubbing and fine desliming, the scrubbing unit 17 is formed by combining a plurality of scrubbing machines in a series connection mode, each scrubbing machine comprises a hexagonal cylinder and stirring blades, an inlet is positioned below the outer side of the hexagonal cylinder of the scrubbing machine, an outlet is positioned above the opposite side of the inlet, each stirring blade is divided into an upper layer, a middle layer and a lower layer, the three layers of blades are positioned on the same stirring shaft, the upper layer of blades and the lower layer of blades have certain angles, the angles of the upper layer of blades and the lower layer of blades are opposite, the upper layer of blades have downward acting force on mortar, the lower layer of blades have upward acting force on the mortar, and the middle blades play a role in horizontal; the material outlet of the scrubbing unit 17 is connected with the inlet of a second spiral deslimer, the material outlet of the second spiral deslimer 18 is connected with the inlet of a deslimer 19, the outlet of the deslimer 19 is connected with the inlet of a sand pump 20, the material outlet of the sand pump 20 is connected with the material inlet of a distributor 21 through a pipeline, the outlet of the distributor 21 is connected with the inlet of a wet-type strong magnetic separator 22, and the magnetically separated materials enter the subsequent post-treatment process.

The post-treatment equipment of the raw sand comprises a linear vibration screening machine combination 23 with a hydraulic sand washing device and a linear vibration dewatering screen 24; the hydraulic sand washing device is arranged above the linear vibrating screen, consists of a plurality of water pipes with a plurality of holes on the pipe walls, and washes sand on the screen surface; the vibrating screen classifier is divided into four to five layers, each layer of the sieve is screened to separate scrubbing sand with different granularities and is conveyed to a dewatering sieve through a pipeline, the lowest layer is a sewage recovery device, and sewage with mud is collected and conveyed to a sewage recycling process; the dewatering screen is a layer of upper screen surface which is scouring sand, the screen is provided with a sewage recovery device, and the removed sewage is conveyed to a sewage treatment and recycling process through the sewage recovery device; the screening unit is two screens for relay screening, the first layer of the first screen is directly conveyed to the sand warehouse, the second layer of the first screen corresponds to the first layer of the second screen, the third layer of the first screen corresponds to the second layer of the second screen, and the rest can be done as required.

The equipment adopted for the sewage recovery treatment comprises a sedimentation tank, a sludge tank, a filter, a sludge scraping and absorbing machine and a belt type filter press. The settling pond consists of a plurality of settling ponds, the settling modes comprise natural settling and flocculation settling, the sewage is naturally settled through the settling pond after being recovered, then the sludge after natural settling is collected through a walking sludge scraping and sucking machine, then the sludge is further settled through adding a flocculating agent, the settled sludge is subjected to filter pressing through a belt filter press to fully separate the sludge from water, so that the sludge with lower water content and the water with lower sludge content are obtained, and the water is filtered through a filter to finally obtain the purer water for the whole scouring sand production; the sludge scraping and sucking machine is provided with a track, the track is positioned on the wall of the sedimentation tank, the sludge scraping and sucking machine stretches over the sedimentation tank and travels on the track at regular time, the sludge scraping and sucking machine is provided with a plurality of pump suction pipes, the pump suction pipes vertically penetrate into the bottom of the sedimentation tank, and the pump suction pipes suck sludge at the bottom of the sedimentation tank into a sludge tank for centralized sedimentation along with the traveling of the sludge scraping and sucking machine; the flocculating agent is added into the sludge tank in proportion through a dosing device, and the flocculated and precipitated sludge is pumped to a belt filter press through a sludge pump for filter pressing treatment, so that the sludge and the water are fully separated finally.

Example 2

1. Referring to fig. 3, a method for recycling waste sand includes the following steps:

and S1, pretreating the waste sand to obtain pretreated waste sand.

The pretreatment of S2 is the same as in step (a) of example 1.

S3 scrubbing, desliming and magnetic separation, the same as in step (b) of example 1.

The post-treatment of S4 is the same as in step (c) of example 1.

S5 drying

The washed sand after being screened enters a drying furnace for drying treatment, moisture in the sand is removed, the sand after being dried enters a buffer tank for storage, the residual magnetic substances in the sand are further magnetically separated by a strong magnetic separator, then the sand enters a linear vibration screening machine for screening treatment, impurities, coarse particle substances and micro powder in the sand are removed, and finally the sand enters a dried sand storage tank for storage. Wherein the drying temperature is 300-400 ℃.

2. Referring to fig. 4, a system for recycling waste sand includes a pretreatment system 100 for waste sand, a pretreatment system 200 for raw sand, a scrubbing, desliming and magnetic separation system 300 for raw sand, a post-treatment system 400, a sewage recovery treatment system (not shown), and a drying system 500.

The raw sand pretreatment system 200, the raw sand scrubbing, desliming and magnetic separation system 300, the post-treatment system 400 and the sewage recovery treatment system are the same as those in example 1.

The pretreatment system 100 for the waste sand comprises a waste sand discharge hopper 1, a magnetic separation belt conveyor 2, a vibration crushing screen 3, a lifter 4, a roughing screening machine 5, a finished product bin 6, a magnetic separator 7, a mechanical regenerator 8 and a boiling dust removal bed 9 which are connected in sequence.

The drying system 500 comprises a three-pass dryer 25, a linear vibration screening machine 26, a bucket elevator 27, a buffer tank 28, a strong magnetic separator 29, a linear vibration screening machine 30, a bucket elevator 31 and a finished product bucket 32 which are connected in sequence.

Further, the equipment used in the drying process may also include a three-pass dryer 25, a bucket elevator 27 (bucket elevator), a bucket elevator 31, a linear vibrating screen classifier 26, a linear vibrating screen classifier 30, a strong magnetic separator 29, a cyclone, a desulfurizing tower, a screw feeder, an induced draft fan, a buffer tank 28, and a finished product tank 32. Wherein, the outlet of the sand scrubbing hopper is connected with the inlet of the screw feeder, the outlet of the screw feeder corresponds to the inlet of the bucket elevator, and the material outlet of the bucket elevator corresponds to the inlet of the three-pass drying furnace; the outlet of the three-pass drying furnace corresponds to the inlet of the bucket elevator, the inlet of the bucket elevator is connected with the inlet of the buffer tank, a strong magnetic separator is arranged below the buffer tank, magnetic substances in sand are further separated, the outlet of the strong magnetic separator corresponds to the inlet of the linear vibrating screen, the outlet of the linear vibrating screen separator corresponds to the inlet of the bucket elevator, the outlet of the bucket elevator is connected with the inlet of a finished product material tank, the tail gas outlet of the drying furnace is connected with a cyclone dust collector, and the cyclone dust collector is connected with a draught fan.

Comparative example 1

A process for producing scouring sand, which differs from example 1 in that:

the pre-treated raw sand firstly enters a first scrubbing machine for rough scrubbing through a buffer bin in scrubbing and desliming, then enters a first spiral desliming machine for first desliming, then enters a combined scrubbing machine (scrubbing unit) for 7 times of fine scrubbing, and then enters a second spiral desliming machine for second desliming, and finally enters a desliming hopper for settlement desliming.

This comparative example differs from example 1 in that the steps of material separation and wet magnetic separation are omitted.

Comparative example 2

A process for producing scouring sand, which differs from example 1 in that:

the pretreated raw sand firstly enters a spiral desliming machine for desliming through a buffer bin during scrubbing and desliming, then enters a combined scrubbing machine for 2 times of fine scrubbing, and enters a desliming hopper for settlement desliming after the fine scrubbing, and then is screened.

The comparative example differs from example 1 in that the steps of primary scrubbing, secondary spiral desliming, wet magnetic separation, 5 times less fine scrubbing in the scrubbing unit, and material separation and wet magnetic separation are omitted.

The results of testing the resulting scouring sands of example 1, comparative example 1 and comparative example 2 above show that:

the content of mud in the scouring sand obtained in the embodiment is 0.15-0.3%, the content of silicon dioxide is 90-96%, and the content of magnetic substances is less than or equal to 1%.

The content of the mud in the scouring sand obtained by the comparative example is 0.3-0.5%, the content of the silicon dioxide is 85-92%, and the content of the magnetic substance is more than or equal to 1.5%.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims (10)

1. A scouring sand production system, the production system comprising:

a raw sand pretreatment system;

scrubbing, desliming and magnetic separation system of raw sand: the device comprises a first scrubbing device, a first desliming device, a second scrubbing device, a second desliming device, a material separating device and a wet magnetic separation device which are connected in sequence; and the outlet of the raw sand pretreatment system is connected with the inlet of the first scrubbing equipment.

2. The scrubbed sand production system of claim 1, wherein the scrubbing, desliming and magnetic separation system of the raw sand includes a first scrubbing apparatus, a first desliming apparatus, a second scrubbing apparatus, a second desliming apparatus, a desliming hopper, a sand pump, a material dividing apparatus and a wet magnetic separation apparatus connected in sequence.

3. The scouring sand production system according to claim 1, wherein the first desliming apparatus and the second desliming apparatus each independently comprise a screw desliming machine;

the second scrubbing device comprises a scrubbing unit consisting of a plurality of scrubbing machines;

the wet magnetic separation equipment comprises a wet cylindrical strong magnetic separator or a wet vertical ring strong magnetic separator.

4. The scouring sand production system according to claim 1, wherein the raw sand pretreatment system comprises a first screening device, a size mixing device and a surge bin which are connected in sequence, and an outlet of the surge bin is connected with an inlet of the first scouring device.

5. The scrubbed sand production system of claim 1 further comprising an aftertreatment system, an inlet of the aftertreatment system connected to an outlet of the wet magnetic separator apparatus;

the post-treatment system comprises second screening equipment and dewatering equipment, wherein an outlet of the second screening equipment is connected with an inlet of the dewatering equipment through a pipeline;

the second screening device comprises a linear vibration screening unit with a hydraulic sand washing device, and the linear vibration screening unit with the hydraulic sand washing device can screen scrubbing sand of various specifications.

6. The scouring sand production system of claim 5, further comprising a wastewater recovery treatment system connected to any one or more of the pre-grit treatment system, the scouring, desliming and magnetic separation system of the grit, or the post-treatment system.

7. A system for reclaiming and reusing waste sand, comprising the sand scouring production system according to any one of claims 1 to 6.

8. The recycling system of waste sand according to claim 7, further comprising a pretreatment system and a drying system of waste sand.

9. The recycling system of waste sand according to claim 8, wherein the drying system comprises a drying device, a second magnetic separation device and a third screening device which are connected in sequence.

10. The system for recycling and regenerating the waste sand of claim 8 or 9, wherein the drying system comprises a drying device, a buffer tank, a second magnetic separation device, a third screening device and a finished product tank which are connected in sequence.

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