A heavy metal-containing waste residue resource treatment method and cat litter prepared therefrom

Abstract

The present application relates to a kind of heavy metal-containing waste slag resource processing method and cat litter prepared by the method, the method comprises: recycling heavy metal in heavy metal-containing waste slag by magnetic separation;Heavy metal recovery of the slag is sintered into porous sintered material, and is screened with 3mm sieve;According to 1wt%~40wt% of waste gypsum content, waste gypsum is mixed with the porous sintered material and / or waste catalyst with particle size less than 3mm, granulated, to obtain the first granule of cat litter;Porous sintered material with particle size greater than 3mm is used as soilless culture substrate;After juicing, food leaf grass residue is broken, mixed with starch, granulated, dried, to obtain the second granule of cat litter;Also includes using used cat litter for planting.The present application uses heavy metal-containing waste slag and juicing food leaf grass residue to prepare cat litter, with low cost, and cat litter can be used as soilless culture substrate after use, zero emission throughout, solve the disposal problem of heavy metal-containing waste slag and food leaf grass residue, improve the added value of heavy metal-containing waste slag, and the prepared cat litter is low in dust and not easy to stick to the pot.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heavy metal-containing waste residue treatment and pet supplies, and particularly relates to a heavy metal-containing waste residue resource treatment method and cat litter prepared by the method. BACKGROUND

[0002] The heavy metal-containing waste residue mainly refers to zeolite, tailings, smelting slag, leaching residue, sludge, waste catalysts and the like containing heavy metals such as copper, lead, zinc, nickel, cobalt, tin, antimony, arsenic, cadmium and mercury. After the valuable metals are recovered from these heavy metal-containing waste residues, the heavy metal-containing waste residues are usually applied to the cement industry and the construction field as additives for concrete and cement and auxiliary materials for new building materials, and have low added value.

[0003] Cat litter, also known as pet litter, has good water absorption and can absorb water in urine or feces and can also be used to bury feces. Common cat litters on the market include paper cat litter, pine cat litter, tofu cat litter, zeolite cat litter and bentonite cat litter.

[0004] Paper cat litter is made of paper pulp into small granular to simulate sand and provide water absorption, which can be poured into the toilet and flushed away, but it is easy to dissolve into a paste during use and is difficult to clean. Pine cat litter can be flushed into the toilet and has no dust, but it is difficult to clean and has a strong pine odor and is prone to mold. Tofu cat litter has good water solubility and can be directly flushed into the toilet, but it is difficult to clean because it is sticky. Pure natural zeolite cat litter has the advantages of large particles, no dust, low consumption and the like, however, the natural zeolite cat litter does not absorb odor and has slow absorption capacity for thin feces, and the thin feces is easy to leak through the cat litter and stick to the litter box or be stepped on by the cat everywhere. Compared with the above types of cat litter, bentonite cat litter has the advantages of fast water absorption, good clumping, easy cleaning and low price, but the dust is large, and if the cat litter pot is placed in the room, the surface of the furniture will gradually be covered with a layer of fine white powder, which is harmful to the respiratory tract of the cat in the long term. In addition, the bentonite cat litter is easy to stick to the pot.

[0005] In order to replace natural zeolite and bentonite, the prior art uses fly ash or natural mineral clay without heavy metals to sinter into ceramic cat litter. These ceramic cat litters are not uniform in size and irregular in shape, and need to be broken and polished after use. In addition, these ceramic cat litters also have the disadvantages of slow water absorption and poor clumping. SUMMARY

[0006] In order to solve the problems of slow water absorption, poor clumping and the need for polishing after use of the existing ceramic cat litter, the present application provides a heavy metal-containing waste residue resource treatment method and cat litter prepared by the method.

[0007] The technical scheme provided by the present application is as follows:

[0008] In a first aspect, the present application provides a heavy metal-containing waste residue resource processing method, comprising:

[0009] The heavy metal in the heavy metal-containing waste residue is recovered by magnetic separation; the heavy metal-containing waste residue comprises waste gypsum, and slag or waste catalyst;

[0010] The slag after recovery of heavy metal is sintered into a porous sintered material, and sieved by a 3mm sieve;

[0011] The waste gypsum is mixed with the porous sintered material and / or waste catalyst with a particle size less than 3mm at a waste gypsum mixing amount of 1wt%-40wt%, granulated, to obtain first granules, which are used as cat litter.

[0012] In some embodiments provided by the present application, the waste gypsum is mixed with the porous sintered material and / or waste catalyst with a particle size less than 3mm at a waste gypsum mixing amount of 20wt%-30wt%.

[0013] In some embodiments provided by the present application, the slag is an acid waste residue, and the waste catalyst is a waste NH3-SCO catalyst, a waste aluminum-silicon-based catalyst or a waste molecular sieve catalyst.

[0014] In some embodiments provided by the present application, the heavy metal-containing waste residue resource processing method further comprises: the porous sintered material with a particle size greater than 3mm is used as a soilless culture substrate.

[0015] In some embodiments provided by the present application, the sintering of the slag after recovery of heavy metal into a porous sintered material comprises:

[0016] The slag, pore-forming agent, binder and water are mixed to form a mixed slurry;

[0017] After the mixed slurry is solidified and formed, sintering is performed to obtain the porous sintered material.

[0018] In some embodiments provided by the present application, the heavy metal-containing waste residue resource processing method further comprises: the leaf grass residue after juice extraction is crushed, mixed with starch, granulated, and dried to obtain second granules, which are used as cat litter.

[0019] In some embodiments provided by the present application, the heavy metal-containing waste residue resource processing method further comprises: the used cat litter is mixed into alkaline soil and planted.

[0020] In a second aspect, the present application provides cat litter, comprising first granules, which are formed by granulation of a porous water-absorbing material, waste gypsum and water, and the waste gypsum accounts for 1wt%-40wt% of the sum of the porous water-absorbing material and the waste gypsum.

[0021] In some embodiments provided by the present application, the porous water-absorbing material is one or more of porous sintered material, carrier of waste catalyst, diatomite, vermiculite, kaolin, bentonite, wollastonite, sepiolite, attapulgite, and volcanic rock; and the waste gypsum is one or more of phosphogypsum, desulfurization gypsum, and natural gypsum.

[0022] In some embodiments provided by the present application, the surface of the first particle is further coated with one or more of gelatin, carboxymethyl starch, carboxymethyl cellulose, and starch.

[0023] In some embodiments provided by the present application, the cat litter further comprises second particles, which are granulated from plant fiber powder and starch; the plant fiber powder comprises at least one of leafy grass residue, bamboo powder, straw powder, coffee residue, tea residue, and distiller's grain residue; and the leafy grass residue is residue after juice extraction.

[0024] In some embodiments provided by the present application, the particle size of the first particle is 1-5 mm, and the particle size of the porous water-absorbing material is less than 3 mm.

[0025] In some embodiments provided by the present application, the particle size of the second particle is 1-10 mm.

[0026] Compared with the prior art, the technical scheme provided by the present application has the following beneficial effects:

[0027] 1. The present application uses heavy metal-containing waste residue and leafy grass residue after juice extraction to prepare cat litter, which has low cost and can be used as a soilless culture medium after use, and the whole process is zero emission, thereby solving the disposal problem of heavy metal-containing waste residue and leafy grass residue and improving the added value of heavy metal-containing waste residue.

[0028] 2. The present application uses porous sintered material and / or waste catalyst with a particle size less than 3 mm screened out as a porous water-absorbing material, which does not need to be polished, and is directly granulated after being mixed with waste gypsum, so that the edges and corners of the porous sintered material are wrapped by the waste gypsum to form a particle with a smooth surface.

[0029] 3. The first particle prepared by the present application has a hardened waste gypsum surface and a porous water-absorbing material inside, which has low dust and is not easy to stick to the litter, has a fast water absorption speed and a large water absorption capacity, and the urea and ammonia in the urine can be fixed by the waste gypsum to reduce odor.

[0030] 4. The second particle prepared by the present application is granulated from plant fiber powder and starch, and the starch has strong bonding effect after water absorption, which can bond the first particles that are not easy to form a group into a group. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description only show some of the embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort based on these drawings.

[0032] Figure 1 First particles prepared for Example 1 ;

[0033] Figure 2 First particles prepared for Example 2. DETAILED DESCRIPTION

[0034] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.

[0035] DEFINITIONS

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0037] The singular terms "a," "an," and "the" include plural referents unless context clearly indicates otherwise. Similarly, the word "or" is intended to include "and" unless the context clearly indicates otherwise. The term "plurality" is synonymous with the phrase "more than one" and is used to mean two or more. The terms "first," "second," and the like, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, and the like. It is also to be understood that the term "3 mm mesh" is an approximation. The term "comprising" means "including." Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure, suitable methods and materials are described below.

[0038] Unless the context clearly indicates otherwise, the description of the term "one embodiment / way," "some embodiments / ways," "example," "specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic being described is included in at least one embodiment / way or example of the application.

[0039] The term "porous water-absorbing material" includes inorganic porous water-absorbing material, organic porous water-absorbing material, inorganic porous water-absorbing material includes one or more of porous sintered material, carrier of waste catalyst, diatomite, vermiculite, kaolin, bentonite, wollastonite, sepiolite, attapulgite, volcanic rock; organic porous water-absorbing material includes freeze-dried protein or polysaccharide material, porous fiber.

[0040] The term "granulation" refers to the process of processing materials into granules, including dry extrusion granulation, boiling granulation, hot melt granulation, stirring granulation, spray drying granulation, and the present application preferably is stirring granulation, liquid or binder is penetrated into solid powder, and the liquid and solid powder are closely contacted by appropriate stirring to generate bonding force to form a lump; the stirring method is rotary disc, cone or cylindrical drum.

[0041] The term "waste catalyst" refers to a catalyst that loses or decreases in catalytic activity due to long-term use, expiration or poisoning, "NH3-SCO catalyst" refers to an ammonia selective catalytic oxidation catalyst, which has good adsorption capacity for ammonia gas. "Aluminum-based catalyst" refers to a catalyst with alumina or silica as a carrier, which has high thermal stability and large specific surface area for ammonia gas; synthetic zeolite is called molecular sieve, "molecular sieve" catalyst is also called "zeolite catalyst", and molecular sieve has acid-base center and can be used for acid-base catalytic reaction

[0042] in the process.

[0043] The term "sintering" refers to heat treatment of powder or compact at a temperature lower than the melting point of the main component to improve its strength by inter-particle bonding.

[0044] The term "heavy metal-containing waste residue" refers to industrial discharged waste residue including blast furnace slag, steel slag, fly ash, pyrite ash, carbide slag, red mud, white mud, coal washing mud, silicon-manganese slag, chromium slag, phosphor gypsum, desulfurization gypsum, waste catalyst, titanium white slag, and waste quartz powder.

[0045] The term "leaf-eating grass" is also called protein grass, and the protein content of leaf-eating grass is 36% to 48.7%, and the leaf-eating grass residue after juicing also contains about 15wt% of protein.

[0046] The term "red mud" is a strong alkaline solid waste generated in the production of alumina from bauxite, and the chemical composition of red mud is as follows: silicon oxide (SiO2): 15-34%; aluminum oxide (Al2O3): 10-16%; iron oxide (Fe2O3): 16-35%; calcium oxide (CaO): 10-32%; sodium oxide (Na2O): 2-8%; magnesium oxide (MgO): 2-8%.

[0047] The term "titanium white slag" is an acidic waste residue produced during the production of titanium white powder, and 0.2-0.3 tons of acidolysis waste residue is produced for every ton of titanium white powder, and the chemical composition mainly includes SiO2, Fe2O3, TiO2, etc.

[0048] The term "carbide slag" is a waste residue produced during the production of polyvinyl chloride and vinyl acetate by the calcium carbide method, and the main component is calcium hydroxide (Ca(OH)2).

[0049] The term "yellow phosphorus slag" is an industrial waste residue discharged during the production of yellow phosphorus by the hot method or the production of phosphoric acid by the acid method, and the main components are CaO and SiO2.

[0050] The term "marble powder" is fine powder obtained after crushing and grinding of marble, or powder obtained during the shaping and processing of marble materials, and the main component is calcium carbonate (CaCO3). DETAILED DESCRIPTION OF THE INVENTION

[0052] The method for recycling heavy metal-containing waste residue provided by the application comprises the following steps: recovering heavy metals in the heavy metal-containing waste residue by magnetic separation; the heavy metal-containing waste residue comprises waste gypsum, and slag or waste catalyst; sintering the slag after the heavy metals are recovered into porous sintered material, and performing screening with a 3mm sieve; mixing the waste gypsum with the porous sintered material and / or the waste catalyst, which have a particle size of less than 3mm, at a waste gypsum mixing amount of 1wt%-40wt%, and granulating to obtain first particles, which are used as cat litter.

[0053] After the heavy metal-containing waste residue recycling method recovers heavy metals in various heavy metal-containing waste residues, the slag is sintered into porous sintered material with strong water absorption and water retention capacity, and does not need to be crushed. The part with a particle size greater than 3mm is used for soilless cultivation, and the particles with a particle size less than 3mm are difficult to transport. These particles with a particle size less than 3mm have a rough surface, edges and corners, are too small, and are easy to form dust, and are generally considered to be unable to be used as cat litter. The application uses waste gypsum to bond the particles with a particle size less than 3mm, to form particles with a smooth surface. The waste gypsum has the ability of fast water absorption, and the internal porous sintered material has the ability of water absorption and water retention, so that the cat litter has the advantages of fast water absorption, large water absorption amount, and difficulty in dust formation.

[0054] The slag includes blast furnace slag, steel slag, fly ash, pyrite ash, carbide slag, red mud, white mud, coal washing mud, silicon-manganese slag, chromium slag, phosphor gypsum, desulfurization gypsum, waste catalyst, titanium white slag, and waste quartz powder. The blast furnace slag, steel slag, fly ash, pyrite ash, carbide slag, red mud, white mud, coal washing mud, silicon-manganese slag, chromium slag, phosphor gypsum, desulfurization gypsum, waste catalyst, titanium white slag, and waste quartz powder are heavy metal-containing waste slag. The blast furnace slag, steel slag, fly ash, pyrite ash, carbide slag, red mud, white mud, coal washing mud, silicon-manganese slag, chromium slag, phosphor gypsum, desulfurization gypsum, waste catalyst, titanium white slag, and waste quartz powder are first treated by using a comprehensive separation technology, valuable metals are recovered and harmless treatment is performed, and secondary waste slag powder is obtained.

[0055] The comprehensive separation technology includes one or more combinations of magnetic separation, gravity separation, and flotation, or is one of multi-stage magnetic separation, multi-stage gravity separation, and multi-stage flotation technology.

[0056] The valuable metals recovered by using the comprehensive separation technology include one or more of the elements or compounds of iron, manganese, vanadium, lead, chromium, cobalt, cerium, copper, cadmium, nickel, and molybdenum, and the total removal rate of the valuable metals is between 90% and 100%.

[0057] In some preferred embodiments, the slag is an acid waste slag, and the waste catalyst is a waste NH3-SCO catalyst. Urea in urine can be decomposed into ammonia, so that the urine has a foul odor. The acid waste slag can fix urea in the urine, reduce the decomposition of urea, and thus reduce the foul odor. The NH3-SCO catalyst has a strong adsorption effect on ammonia, which can reduce the escape of ammonia decomposed from urea.

[0058] In some embodiments provided by the present application, the heavy metal-containing waste slag resource treatment method provided by the present application further includes: a porous sintered material with a particle size greater than 3 mm is used as a soilless culture substrate. The porous sintered material prepared from the slag has strong water absorption and water retention capacity, and is rich in mineral elements, and can be used to replace natural porous water absorption materials for soilless culture.

[0059] In some embodiments provided by the present application, the sintering of the heavy metal-recovered slag into a porous sintered material includes: mixing the slag, a pore-forming agent, a binder, and water to form a mixed slurry; and sintering after the mixed slurry is solidified and formed, to obtain the porous sintered material.

[0060] In some embodiments provided by the present application, the heavy metal-containing waste slag resource treatment method provided by the present application further includes: crushing the leaf grass residue after juicing, mixing with starch, granulating, drying, to obtain second particles, which are used as cat litter.

[0061] In some embodiments provided by the present application, the heavy metal-containing waste residue resource treatment method further comprises: planting after the used cat litter is mixed into the alkaline soil. The used cat litter contains not only urine which can be used as fertilizer, but also mineral calcium sulfate (waste gypsum), and the porous water-absorbing material has water absorption and water retention functions, and the waste gypsum has the ability to neutralize the alkaline soil, and can be used for alkaline soil modification.

[0062] In some embodiments provided by the present application, in the granulation process, in addition to using enough water to ensure sufficient mixing, a binder (for example, cement) can also be added to improve the strength of the waste gypsum.

[0063] Based on the heavy metal-containing waste residue resource treatment method, the present application obtains a cat litter with all raw materials derived from solid waste, which comprises first particles, the first particles are formed by granulation of porous sintered material and / or waste catalyst, waste gypsum and water, and the waste gypsum accounts for 1wt% to 40wt% of the sum of the porous sintered material and / or waste catalyst and the waste gypsum. The waste gypsum is weakly acidic, can react with urea in urine to form urea sulfate salt, prevent urea from decomposing into ammonia gas, and can prevent urine odor.

[0064] In addition, the porous sintered material and / or waste catalyst can also be replaced by natural porous water-absorbing materials, which include one or more of diatomite, vermiculite, kaolin, bentonite, wollastonite, sepiolite, attapulgite, and volcanic rock. The present application uses waste gypsum to wrap these porous water-absorbing materials to form particles with smooth surfaces, avoiding the rough or angular inorganic particles to scratch the animal fur or the parts not covered by fur, such as paws and nose.

[0065] In some embodiments provided by the present application, the porous water-absorbing material is one or more of porous sintered material, carrier of waste catalyst, diatomite, vermiculite, kaolin, bentonite, wollastonite, sepiolite, attapulgite, and volcanic rock; the waste gypsum is one or more of phosphogypsum,

[0066] desulfurization gypsum, titanium gypsum, and natural gypsum.

[0067] In some embodiments provided by the present application, the surface of the first particles is further coated with one or more of gelatin, carboxymethyl starch, carboxymethyl cellulose, starch, and mucin. These substances have certain viscosity after absorbing water, and can promote the agglomeration of the first particles.

[0068] In some embodiments provided by the present application, the cat litter further comprises second particles, the second particles being formed by granulating plant fiber powder and starch; the plant fiber powder comprises at least one of leafy grass residue, bamboo powder, straw powder, coffee residue, tea residue and distiller's grains; the leafy grass residue is the residue after the leafy grass is squeezed.

[0069] In some embodiments provided by the present application, the particle size of the first particles is 1-5 mm, and the particle size of the porous water-absorbing material is less than 3 mm; the particle size of the second particles is 1-10 mm.

[0070] In the embodiments provided by the present application, the cat litter comprises the first particles and the second particles, the first particles account for 30wt%-90wt% of the sum of the first particles and the second particles, further, the first particles account for 50wt%-85wt% of the sum of the first particles and the second particles; and more further, the first particles account for 80wt%-85wt% of the sum of the first particles and the second particles.

[0071] In the embodiments provided by the present application, the cat litter further comprises a deodorizing factor, for example, baking soda powder.

[0072] The technical solutions of the present application are described in detail below through specific embodiments:

[0073] Embodiment 1

[0074] (1) 50 parts of water are prepared, and fly ash 70 parts, red mud 15 parts, titanium white residue 7 parts, straw powder 5 parts, marble powder and glass powder 3 parts are added into the water for stirring and mixing to obtain a mixed slurry; then the mixed slurry is poured into a mold with a size of 400mm×400mm×70mm for preliminary solidification molding, and after the shape no longer deforms, it is placed for 10 hours to be taken out of the mold to obtain a green body.

[0075] (2) The green body is sintered in air, and after cooling, a porous sintered material is obtained, the sintering temperature is 1200℃, and the sintering time is 2 hours.

[0076] (3) The porous sintered material is crushed into particles, and then passed through a 3mm sieve, and the sieve residue (+3mm) is used as a soilless culture medium;

[0077] (4) The porous sintered material with a particle size less than 3mm (sieve residue) is mixed with phosphogypsum at a weight ratio of 7:3, and then water is sprayed for granulation to obtain the first particles.

[0078] It is detected that the particle size of the first particles is 1-5 mm, the water absorption rate is 80%, the compressive strength is 10.3MPa, and the dust emission rate is 0.05%.

[0079] Example 2

[0080] (1) 50 parts of water was prepared, waste NH3-SCO catalyst (γ-Al2O3) 62 parts, fly ash 15 parts, titanium white slag 7 parts, konjac powder 10 parts, basalt powder 6 parts were added into the water for stirring and mixing to obtain a mixed slurry; the mixed slurry was then poured into a mold with a size of 400 mm x 400 mm x 70 mm for preliminary solidification molding, and after the shape no longer deformed, it was placed for 10 hours to be taken out of the mold to obtain a green body.

[0081] (2) The green body was sintered in air, and after cooling, a porous sintered material was obtained, the sintering temperature was 1200℃, and the sintering time was 2 hours.

[0082] (3) After the porous sintered material was crushed into particles, it was passed through a 3 mm sieve, and the oversize (+3 mm) was used as a soilless culture medium;

[0083] (4) The porous sintered material with a particle size of <3 mm (undersize) was mixed with desulfurized gypsum at a weight ratio of 8:2, and then water was sprayed to form granules to obtain first granules.

[0084] After detection, the particle size of the first granules was 1-5 mm, the water absorption rate was 88%, the compressive strength was 7.5 MPa, and the dusting rate was 0.03%.

[0085] Example 3

[0086] (1) Fresh leaf-eating grass was pulped, and the residue was filtered out. The pulp was used to extract leaf-eating grass protein, and the residue was dried and crushed to obtain leaf-eating grass residue.

[0087] (2) The leaf-eating grass residue was mixed with starch at a weight ratio of 85 parts of leaf-eating grass residue and 15 parts of wheat starch, then water was sprayed and granulated, and dried to obtain second granules.

[0088] After detection, the particle size of the second granules was 1-10 mm, the water absorption rate was 75%, and the dusting rate was 0.01%. The second granules became soft and had some stickiness after absorbing water, and were easy to form a ball.

[0089] Example 4

[0090] The first granules obtained in Example 1 and the second granules obtained in Example 3 were mixed at a weight ratio of 85:15 to obtain a cat litter composition.

[0091] A 10 cm thick cat litter composition was laid in a cat litter basin, and 50 mL of urea solution (5 mmol / L) was poured into it to observe the absorption. The cat litter composition could absorb all the liquid within 5 seconds, and there was no leakage at the bottom of the basin and no obvious odor.

[0092] A 10 cm thick cat litter composition is laid in a cat litter tray, 30 mL of cooked corn starch paste (10 wt%) is poured into the cat litter composition to observe the absorption, the cat litter composition can absorb the moisture in 9 seconds, the corn starch paste does not flow, and there is no leakage at the bottom of the tray.

[0093] The second particles become soft after absorbing the liquid, have certain viscosity, can stick the first particles into a group, and are easy to shovel out.

[0094] Example 5

[0095] The first particles obtained in Example 2 and the second particles obtained in Example 3 are mixed at a weight ratio of 80:20 to obtain a cat litter composition.

[0096] A 10 cm thick cat litter composition is laid in a cat litter tray, 50 mL of urea solution (5 mmol / L) is poured into the cat litter composition to observe the absorption, the cat litter composition can absorb the liquid in 6 seconds, and there is no leakage at the bottom of the tray and no odor.

[0097] A 10 cm thick cat litter composition is laid in a cat litter tray, 30 mL of cooked corn starch paste (10 wt%) is poured into the cat litter composition to observe the absorption, the cat litter composition can absorb the moisture in 10 seconds, the corn starch paste does not flow, and there is no leakage at the bottom of the tray.

[0098] The second particles become soft after absorbing the liquid, have certain viscosity, can stick the first particles into a group, and are easy to shovel out.

[0099] The above only describes specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for the resource utilization treatment of waste residue containing heavy metals, characterized in that, include: Heavy metals are recovered from waste residue containing heavy metals by magnetic separation; the waste residue containing heavy metals includes waste gypsum and slag. The slag from which heavy metals have been recovered is sintered into porous sintered material. The porous sintered material is then crushed into particles and sieved using a 3mm mesh sieve. Porous sintered material with a particle size greater than 3mm is used as a soilless cultivation substrate. The process of sintering slag after heavy metal recovery into a porous sintered material includes: mixing slag, a pore-forming agent, a binder, and water to form a mixed slurry; after the mixed slurry is solidified and sintered, a porous sintered material is obtained. The waste gypsum is mixed with porous sintered material with a particle size of less than 3 mm at a dosage of 1wt%~40wt%, and granulated. The waste gypsum is used to wrap the edges and corners of the porous sintered material to form the first particle with a smooth surface, which is used as cat litter. The pulpy leafy grass after juicing is crushed, mixed with starch, granulated, and dried to obtain a second granule, which is used as cat litter. The cat litter contains a first granule and a second granule, with the first granule accounting for 30wt% to 90wt% of the sum of the first and second granules. Used cat litter was mixed into alkaline soil before planting.

2. A type of cat litter, characterized in that: include: The first particle is formed by granulation of porous sintered material, waste gypsum, and water, and the edges and corners of the porous sintered material are wrapped with waste gypsum. The porous sintered material is sintered from slag after heavy metal recovery. Its preparation method includes: mixing slag, pore-forming agent, binder and water to form a mixed slurry; after the mixed slurry is solidified and sintered, a porous sintered material is obtained; the waste gypsum accounts for 1wt% to 40wt% of the sum of the porous sintered material and the waste gypsum; the surface of the first particle is also coated with one or more of gelatin, carboxymethyl starch, carboxymethyl cellulose and starch. The second granule is made from plant fiber powder and starch granules; the plant fiber powder includes at least one of leafy grass residue, bamboo powder, straw powder, coffee grounds, tea leaves, and distiller's grains; the leafy grass residue is the residue after juicing leafy grass. The first particle accounts for 30wt% to 90wt% of the sum of the first and second particles.

3. The cat litter according to claim 2, characterized in that: The waste gypsum is one or more of phosphogypsum, desulfurized gypsum, and natural gypsum.

4. The cat litter according to claim 2, characterized in that: The particle size of the first particle is 1 to 5 mm, and the particle size of the porous sintered material is less than 3 mm.

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