A coal chemical gasification filter cake resource system and resource method

Abstract

The present invention belongs to the technical field of coal chemical industry, and in particular, relates to a coal chemical gasification filter cake resource system and resource method. The system provided by the present invention includes: a stirring barrel, on which a gasification filter cake inlet, a modified wastewater inlet and a discharge port are arranged; an oxidation modifier whose discharge port is connected to the modified wastewater inlet of the stirring barrel, and the oxidation modifier is provided with an oily wastewater inlet; a first flotation tank whose feed port is connected to the discharge port of the stirring barrel; a second flotation tank whose feed port is connected to the concentrate outlet of the first flotation tank; a first thickener whose feed port is connected to the concentrate outlet of the second flotation tank; a first filter press whose feed port is connected to the underflow port of the first thickener; a second thickener whose feed port is connected to the tailings outlet of the first flotation tank; and a second filter press whose feed port is connected to the underflow port of the second thickener. The resource system provided by the present invention has a simple process flow, low operating cost, good indicators of sorted products, and good economic and environmental benefits.

Description

Technical Field

[0001] The invention belongs to the technical field of coal chemical industry, and in particular relates to a coal chemical industry gasification filter cake resource utilization system and resource utilization method. Background Art

[0002] my country's coal chemical industry continues to maintain a high-speed growth trend, and coal chemical projects are springing up all over the country, which brings with it a large amount of emission of coal gasification ash, which not only occupies a large amount of land, but also its leachate will cause serious pollution to the soil and water. Therefore, the disposal and utilization of coal gasification ash has become a pressing social issue.

[0003] Coal gasification ash includes gasification furnace slag (coarse slag) and gasification filter cake (fine slag). At present, the utilization direction of coal chemical gasification filter cake at home and abroad is mostly building materials, but building materials have their economic applicability radius. In relatively backward economic areas, the demand for building materials is low and insufficient to absorb large quantities of gasification filter cake. At the same time, due to the high carbon content in gasification filter cake (about 20%), when it is used as an admixture or aggregate to prepare concrete, it is easy to cause the slurry to have increased consistency, poor fluidity, long solidification time, reduced strength, and may affect the durability of concrete.

[0004] Carbon extraction by flotation is also an important research direction for the resource utilization of gasification filter cakes. Gasification filter cakes contain a large amount of residual carbon, so they can be enriched and recovered through flotation technology to achieve resource utilization. However, due to the fine particle size of the ash residue of the gasification filter cake and the high abundance of surface pores, the ash residue of the gasification filter cake has extremely high surface energy, which causes the flotation process to have problems such as high drug consumption and poor selectivity, which in turn leads to an increase in flotation costs and a decrease in the quality of flotation products. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a coal chemical gasification filter cake resource system and resource method. The resource system provided by the present invention has a simple process flow, low operating cost, and can obtain high-carbon products and high-ash products with good indicators.

[0006] The present invention provides a coal chemical gasification filter cake resource system, comprising:

[0007] A stirring barrel, on which a gasification filter cake inlet, a modified wastewater inlet, a dispersing agent dosing port, a collecting agent dosing port, a foaming agent dosing port and a discharge port are arranged;

[0008] An oxidation modification machine whose discharge port is connected to the modified wastewater inlet of the mixing barrel, and the oxidation modification machine is provided with an oily wastewater inlet;

[0009] A first flotation tank having a feed inlet connected to a discharge outlet of the mixing barrel;

[0010] A second flotation cell having a feed inlet connected to a concentrate outlet of the first flotation cell;

[0011] a first thickener having a feed inlet connected to a concentrate outlet of the second flotation cell;

[0012] a first filter press having a feed inlet connected to an underflow outlet of the first thickener;

[0013] a second thickener having a feed inlet connected to the tailings outlet of the first flotation cell;

[0014] A second filter press having a feed inlet connected to the underflow outlet of the second thickener.

[0015] Preferably, the system further comprises a third flotation cell disposed between the tailings outlet of the first flotation cell and the feed inlet of the second thickener;

[0016] The feed inlet of the third flotation cell is connected to the tailings outlet of the first flotation cell, the concentrate outlet of the third flotation cell is connected to the feed inlet of the second flotation cell, and the tailings outlet of the third flotation cell is connected to the feed inlet of the second thickener.

[0017] Preferably, the third flotation tank is provided with a collector dosing port and a frother dosing port.

[0018] Preferably, the system further comprises a fourth flotation cell disposed between the tailings outlet of the third flotation cell and the feed inlet of the second thickener;

[0019] The feed inlet of the fourth flotation cell is connected to the tailings outlet of the third flotation cell, the concentrate outlet of the fourth flotation cell is connected to the feed inlet of the second flotation cell, and the tailings outlet of the fourth flotation cell is connected to the feed inlet of the second thickener.

[0020] Preferably, the fourth flotation tank is provided with a collector dosing port and a frother dosing port.

[0021] Preferably, the system further comprises a feeding bin for storing the gasified filter cake, and the discharge port of the feeding bin is connected to the gasified filter cake inlet of the mixing barrel.

[0022] Preferably, both the first thickener and the second thickener are provided with flocculant dosing ports.

[0023] Preferably, the tailings outlet of the second flotation cell is connected to the feed inlet of the first flotation cell.

[0024] The present invention provides a method for recycling coal chemical gasification filter cake, comprising the following steps:

[0025] a) mixing the gasification filter cake, the dispersion adjusting agent, the collector, the foaming agent and the oxidatively modified oily wastewater to obtain a slurry;

[0026] b) performing flotation roughing on the slurry to obtain roughing concentrate foam and roughing tailings slurry;

[0027] c) flotation separation of the rougher concentrate foam, and then concentrating and filtering the obtained concentrated concentrate foam to obtain a high-carbon product;

[0028] d) concentrating and filtering the roughing tailings slurry to obtain a high-ash product;

[0029] There is no order requirement for step c) and step d).

[0030] Preferably, the step d) specifically comprises:

[0031] d1) flotation scavenging the roughing tailings slurry to obtain scavenging concentrate foam and scavenging tailings slurry;

[0032] d2) incorporating the scavenging concentrate foam into the roughing concentrate foam; and concentrating and filter-pressing the scavenging tailings slurry to obtain a high-ash product.

[0033] Compared with the prior art, the present invention provides a coal chemical gasification filter cake resource system and resource method. The resource system provided by the present invention includes: a stirring barrel, on which a gasification filter cake inlet, a modified wastewater inlet, a dispersing regulator dosing port, a collector dosing port, a frother dosing port and a discharge port are arranged; an oxidation modifier whose discharge port is connected to the modified wastewater inlet of the stirring barrel, and the oxidation modifier is provided with an oily wastewater inlet; a first flotation tank whose feed port is connected to the discharge port of the stirring barrel; a second flotation tank whose feed port is connected to the concentrate outlet of the first flotation tank; a first thickener whose feed port is connected to the concentrate outlet of the second flotation tank; a first filter press whose feed port is connected to the underflow port of the first thickener; a second thickener whose feed port is connected to the tailings outlet of the first flotation tank; and a second filter press whose feed port is connected to the underflow port of the second thickener. When the system is in operation, the gasified filter cake and the oily wastewater treated by the oxidation modifier are first transported to the mixing barrel, and a dispersing agent is added to the mixing barrel, and an appropriate amount of collector and frother are added to obtain a mixed slurry; then the mixed slurry enters the flotation tank for flotation to obtain a flotation concentrate (high carbon foam) and a flotation tailing (high ash tailing slurry); finally, the flotation concentrate and tailings are processed in the corresponding thickener and filter press, respectively, to obtain a high carbon product and a high ash product. The resource utilization system provided by the present invention can achieve the purpose of forced dispersion by adding a dispersant to adjust the rheological properties of the filter cake slurry system and the electrical properties of the material surface, thereby creating favorable conditions for the next flotation process; by subjecting the oily wastewater to corresponding oxidation modification treatment, the collector in the flotation process can be completely or partially replaced, thereby greatly reducing the cost of the flotation process. In the present invention, after the filter cake is subjected to the flotation carbon extraction process and dehydration treatment, the ash content of the high-carbon product is reduced, and the volatile matter and carbon content are significantly increased, thereby improving its combustion characteristics. At the same time, the calorific value is close to the calorific value of coal, and the high-carbon product can be directly put into the boiler equipment and mixed with the coal fuel for combustion; the carbon content of the tailings product can be as low as 1wt% or less, and the ash content can be as high as 95wt% or more, and can be used to prepare additives for concrete. The resource utilization system provided by the present invention has a simple process flow, low operating cost, good indicators of the sorted products, and good economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0035] Figure 1 This is a simplified process flow diagram of a coal chemical gasification filter cake resource system provided by an embodiment of the present invention;

[0036] Figure 2 It is a schematic diagram of the process flow of the coal chemical gasification filter cake resource utilization system provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The present invention provides a coal chemical gasification filter cake resource system, comprising:

[0039] A stirring barrel, on which a gasification filter cake inlet, a modified wastewater inlet, a dispersing agent dosing port, a collecting agent dosing port, a foaming agent dosing port and a discharge port are arranged;

[0040] An oxidation modification machine whose discharge port is connected to the modified wastewater inlet of the mixing barrel, and the oxidation modification machine is provided with an oily wastewater inlet;

[0041] A first flotation tank having a feed inlet connected to a discharge outlet of the mixing barrel;

[0042] A second flotation cell having a feed inlet connected to a concentrate outlet of the first flotation cell;

[0043] a first thickener having a feed inlet connected to a concentrate outlet of the second flotation cell;

[0044] a first filter press having a feed inlet connected to an underflow outlet of the first thickener;

[0045] a second thickener having a feed inlet connected to the tailings outlet of the first flotation cell;

[0046] A second filter press having a feed inlet connected to the underflow outlet of the second thickener.

[0047] See also Figure 1 , Figure 1 It is a simplified process flow diagram of a coal chemical gasification filter cake resource utilization system provided by an embodiment of the present invention.

[0048] The resource recovery system provided by the present invention comprises a stirring barrel, an oxidation modifier, a first flotation tank, a second flotation tank, a first thickener, a first filter press, a second thickener and a second filter press. The stirring barrel is used to forcibly disperse the gasification filter cake and mix the materials uniformly, and is provided with a gasification filter cake inlet, a modified wastewater inlet, a dispersion regulator dosing port, a collector dosing port, a foaming agent dosing port and a discharge port.

[0049] In the resource recovery system provided by the present invention, the oxidation modifier is used to oxidatively modify oily wastewater, and is provided with an oily wastewater inlet and a discharge port, and the discharge port of the oxidation modifier is connected to the modified wastewater inlet of the mixing barrel.

[0050] In the resource recovery system provided by the present invention, the first flotation tank is provided with a feed inlet, a concentrate outlet and a tailings outlet, and the feed inlet of the first flotation tank is connected to the discharge outlet of the stirring barrel, and is used to perform rough selection on the gasification filter cake mixed slurry discharged from the discharge outlet of the stirring barrel. In one embodiment provided by the present invention, the first flotation tank is a transmission-free flotation tank.

[0051] In the resource recovery system provided by the present invention, the second flotation cell is provided with a feed port, a concentrate outlet and a tailings outlet, and the feed port of the second flotation cell is connected to the concentrate outlet of the first flotation cell, and is used to concentrate the rough concentrate foam discharged from the concentrate outlet of the first flotation cell. In one embodiment provided by the present invention, the second flotation cell is a transmission-free flotation cell. In one embodiment provided by the present invention, the tailings outlet of the second flotation cell is connected to the feed port of the first flotation cell.

[0052] In the resource recovery system provided by the present invention, the first thickener is provided with a feed port, an overflow port and an underflow port. The feed port of the first thickener is connected to the concentrate outlet of the second flotation tank, and is used to concentrate the selected concentrate foam discharged from the concentrate outlet of the second flotation tank. In one embodiment of the present invention, the first thickener is also provided with a flocculant dosing port. In one embodiment of the present invention, the inner diameter of the tank body of the first thickener is preferably 3000-8000mm, specifically 6000mm; the height of the tank body is preferably 1000-5000mm, specifically 2300mm; the sedimentation area is preferably 20-40m 2 , specifically 27.6m 2 In one embodiment provided by the present invention, the model of the first thickener is GX-6.

[0053] In the resource recovery system provided by the present invention, the first filter press is provided with a feed inlet, a filtrate outlet and a solid material outlet, and the feed inlet of the first filter press is connected to the underflow outlet of the first thickener, and is used to filter the underflow slurry discharged from the underflow outlet of the first thickener to obtain a high-carbon product (solid material). In one embodiment of the present invention, the filtration area of ​​the first filter press is preferably 50 to 200 m 2 , specifically 50m 2 、100m 2 、150m 2 or 200m 2In one embodiment of the present invention, the model of the first filter press is Z100 / 1250-30U.

[0054] In the resource recovery system provided by the present invention, the second thickener is provided with a feed port, an overflow port and an underflow port. The feed port of the second thickener is connected to the tailings outlet of the first flotation tank, and is used to concentrate the roughing tailings slurry discharged from the tailings outlet of the first flotation tank. In one embodiment of the present invention, the second thickener is also provided with a flocculant dosing port. In one embodiment of the present invention, the inner diameter of the tank body of the second thickener is preferably 3000-8000mm, specifically 6000mm; the height of the tank body is preferably 1000-5000mm, specifically 2300mm; the sedimentation area is preferably 20-40m 2 , specifically 27.6m 2 In one embodiment provided by the present invention, the model of the second thickener is GX-6.

[0055] In the resource recovery system provided by the present invention, the second filter press is provided with a feed inlet, a filtrate outlet and a solid material outlet, and the feed inlet of the second filter press is connected to the underflow outlet of the second thickener, and is used to filter the underflow slurry discharged from the underflow outlet of the second thickener to obtain a high-ash product (solid material). In one embodiment of the present invention, the filtration area of ​​the second filter press is preferably 50 to 200 m 2 , specifically 50m 2 、100m 2 、150m 2 or 200m 2 In one embodiment of the present invention, the model of the second filter press is Z100 / 1250-30U.

[0056] In one embodiment provided by the present invention, the system further comprises a feed bin, the feed bin is used to store the gasification filter cake, and is provided with a feed port and a discharge port, the discharge port of the feed bin is connected to the gasification filter cake inlet of the mixing barrel. In one embodiment provided by the present invention, the discharge port of the feed bin is connected to the gasification filter cake inlet of the mixing barrel through a feeder.

[0057] In one embodiment provided by the present invention, the system further comprises a third flotation cell, the third flotation cell is arranged between the tailings outlet of the first flotation cell and the feed inlet of the second thickener, and is provided with a feed inlet, a concentrate outlet and a tailings outlet, the feed inlet of the third flotation cell is connected to the tailings outlet of the first flotation cell, the concentrate outlet of the third flotation cell is connected to the feed inlet of the second flotation cell, and the tailings outlet of the third flotation cell is connected to the feed inlet of the second thickener. In the present invention, the third flotation cell is used to scavenge the roughing tailings slurry discharged from the tailings outlet of the first flotation cell, the scavenge concentrate foam obtained by scavenging is transported to the second flotation cell for concentrating, and the scavenge tailings slurry obtained by scavenging is transported to the second thickener for concentrating. In one embodiment provided by the present invention, the third flotation cell is also provided with a collector dosing port and a frother dosing port. In one embodiment provided by the present invention, the third flotation cell is a transmission-free flotation cell.

[0058] In one embodiment provided by the present invention, the system further comprises a fourth flotation cell, the fourth flotation cell is arranged between the tailings outlet of the third flotation cell and the feed port of the second thickener, and is provided with a feed port, a concentrate outlet and a tailings outlet, the feed port of the fourth flotation cell is connected to the tailings outlet of the third flotation cell, the concentrate outlet of the fourth flotation cell is connected to the feed port of the second flotation cell, and the tailings outlet of the fourth flotation cell is connected to the feed port of the second thickener. In the present invention, the fourth flotation cell is used to perform secondary scavenging on the scavenged tailings slurry discharged from the tailings outlet of the third flotation cell, the secondary scavenged concentrate foam obtained by the secondary scavenging is transported to the second flotation cell for selection, and the secondary scavenged tailings slurry obtained by the secondary scavenging is transported to the second thickener for concentration. In one embodiment provided by the present invention, the fourth flotation cell is also provided with a collector dosing port and a frother dosing port. In one embodiment provided by the present invention, the fourth flotation cell is a transmission-free flotation cell.

[0059] The present invention also provides a method for recycling coal chemical gasification filter cake, comprising the following steps:

[0060] a) mixing the gasification filter cake, the dispersion adjusting agent, the collector, the foaming agent and the oxidatively modified oily wastewater to obtain a slurry;

[0061] b) performing flotation roughing on the slurry to obtain roughing concentrate foam and roughing tailings slurry;

[0062] c) flotation separation of the rougher concentrate foam, and then concentrating and filtering the obtained concentrated concentrate foam to obtain a high-carbon product;

[0063] d) concentrating and filtering the roughing tailings slurry to obtain a high-ash product;

[0064] There is no order requirement for step c) and step d).

[0065] In the resource recovery method provided by the present invention, the gasification filter cake, the dispersing adjusting agent, the collecting agent, the foaming agent and the oxidatively modified oily wastewater are first mixed. The water content of the gasification filter cake is preferably 40-60wt%, specifically 40wt%, 45wt%, 50wt%, 55wt% or 60wt%; the carbon content of the gasification filter cake is preferably 10-30wt%, specifically 10wt%, 15wt%, 20wt%, 25wt% or 30wt%; the oxidatively modified oily wastewater is obtained by treating the oily wastewater in an oxidative modifier; the oil content of the oily wastewater is preferably 400-600g / L, specifically 400g / L, 450g / L, 500g / L, 550g / L or 600g / L. / L; the specific process of the treatment includes: mixing the oily wastewater with methanol and then performing oxidation modification in the presence of sodium hydroxide and aluminum oxide; the molar ratio of the oily wastewater to the methanol based on pure water is preferably (3-8):1, specifically 3:1, 4:1, 5:1, 6:1, 7:1 or 8:1; the amount of the sodium hydroxide is preferably 0.5-3wt% of the mass of the oily wastewater, more preferably 1-1.8wt%; the amount of the aluminum oxide is preferably 0.01-0.1wt% of the mass of the oily wastewater, more preferably 0.03-0.05wt%; the oxidation modification machine is preferably the above-mentioned The oxidation modifier is preferably HXAd-3#, which is provided by Huaxin Flotation Company; based on the unit mass of dry gasification filter cake, the addition amount of the dispersing agent is preferably 1-5kg / t, specifically 1kg / t, 1.5kg / t, 2kg / t, 2.5kg / t, 3kg / t, 3.5kg / t, 4kg / t, 4.5kg / t or 5kg / t; the collector is preferably kerosene; based on the unit mass of dry gasification filter cake, the addition amount of the collector is preferably 1-10kg / t, specifically 1kg / t, 2kg / t, 3kg / t, 4kg / t, 5kg / t, 6kg / t, 7kg / t, 8kg / t, 9kg / t or 10kg / t; the foaming agent is preferably 2# oil (pine oil); based on unit mass of dry gasification filter cake, the added amount of the foaming agent is preferably 500-1000g / t, specifically 500g / t, 550g / t, 600g / t, 650g / t, 700g / t, 750g / t, 800g / t, 850g / t, 900g / t, 950g / t or 1000g / t; the mixing is preferably carried out in the stirring barrel introduced above. After uniform mixing, a slurry is obtained, and the solid content of the slurry is preferably 10-20wt%, specifically 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt% or 20wt%.

[0066] In the resource recovery method provided by the present invention, after the mixed slurry is obtained, the slurry is subjected to flotation roughing. Wherein, the flotation roughing is preferably carried out in the first flotation tank introduced above; the frother added in the flotation roughing is preferably 2# oil, and the addition amount of the frother in the flotation roughing system is preferably 100-1000g / t, specifically 100g / t, 200g / t, 300g / t, 400g / t, 500g / t, 600g / t, 700g / t, 800g / t, 900g / t or 1000g / t; the collector added in the flotation roughing is preferably kerosene, and the addition amount of the kerosene in the flotation roughing system is preferably 1-10kg / t, specifically 1kg / t, 2kg / t, 3kg / t, 4kg / t, 4.2kg / t, 5kg / t, 6kg / t, 7kg / t, 8kg / t, 9kg / t or 10kg / t. After flotation roughing, roughing concentrate foam and roughing tailings slurry are obtained.

[0067] In the resource recovery method provided by the present invention, after the roughing concentrate foam is obtained, the roughing concentrate foam is subjected to flotation and concentration. Wherein, the flotation and selection is preferably carried out in the second flotation tank described above; the frother added in the flotation and selection is preferably 2# oil, and the addition amount of the frother in the flotation and selection system is preferably 100-1000g / t, specifically 100g / t, 200g / t, 300g / t, 400g / t, 500g / t, 600g / t, 700g / t, 800g / t, 900g / t or 1000g / t; the collector added in the flotation and selection is preferably kerosene, and the addition amount of the kerosene in the flotation and selection system is preferably 1-10kg / t, specifically 1kg / t, 2kg / t, 3kg / t, 4kg / t, 5kg / t, 5.1kg / t, 6kg / t, 7kg / t, 8kg / t, 9kg / t or 10kg / t. After flotation and selection, selected concentrate foam and selected tailings slurry are obtained.

[0068] In the resource recovery method provided by the present invention, after obtaining the selected tailings slurry and the selected concentrate foam, the selected tailings slurry is preferably returned to the flotation roughing process for flotation roughing again; the selected concentrate foam is concentrated and filtered in turn. In which, during the concentration process, a certain amount of flocculant is preferably added to the selected concentrate foam; the grade of the flocculant is preferably H66, and the flocculant of this grade is provided by Huaxin Flotation Company; the amount of the flocculant added to the selected concentrate foam is preferably 10 to 40 g / t, specifically 10g / t, 15g / t, 20g / t, 25g / t, 30g / t, 35g / t or 40g / t; the concentration is preferably carried out in the first thickener described above; the filter press is preferably carried out in the first filter press described above. After the filter press is completed, a high-carbon product is obtained, and the water content of the high-carbon product is preferably ≤20wt%, more preferably ≤18wt%. In the present invention, the supernatant overflowing during the concentration process and the filtrate generated during the filter pressing process can be used as recycled water and returned to the flotation process or used for other purposes.

[0069] In the resource recovery method provided by the present invention, after obtaining the roughing tailings slurry, the roughing tailings slurry is concentrated and filtered in sequence. In the process of concentration, a certain amount of flocculant is preferably added to the tailings slurry; the grade of the flocculant is preferably H66; the amount of the flocculant added to the tailings slurry is preferably 5 to 30 g / t, specifically 5 g / t, 10 g / t, 15 g / t, 20 g / t, 25 g / t or 30 g / t; the concentration is preferably carried out in the second thickener described above; the filter pressing is preferably carried out in the second filter press described above. After the filter pressing, a high-ash product is obtained, and the water content of the high-ash product is preferably ≤35wt%, more preferably ≤30wt%. In the present invention, the supernatant overflowing in the concentration process and the filtrate generated in the filter pressing process can be used as recycled water and returned to the flotation process or used for other purposes.

[0070] In the resource utilization method provided by the present invention, in order to improve the flotation effect and reduce the carbon content of high-ash products, it is preferred not to directly concentrate and filter-press the roughing tailings slurry, but to first perform flotation scavenging on the roughing tailings slurry, and then concentrate and filter-press the scavenging tailings slurry to obtain high-ash products.

[0071] The specific steps include:

[0072] d1) flotation scavenging the roughing tailings slurry to obtain scavenging concentrate foam and scavenging tailings slurry;

[0073] d2) incorporating the scavenging concentrate foam into the roughing concentrate foam; and concentrating and filter-pressing the scavenging tailings slurry to obtain a high-ash product.

[0074] In the above-mentioned steps including scavenging process provided by the present invention, the flotation scavenging is preferably carried out in the third flotation tank introduced above; the frother added in the flotation scavenging is preferably 2# oil, and the addition amount of the frother in the flotation scavenging system is preferably 100-500g / t, specifically 100g / t, 150g / t, 200g / t, 250g / t, 300g / t, 350g / t, 400g / t, 450g / t or 500g / t; the collector added in the flotation scavenging is preferably kerosene, and the addition amount of the kerosene in the flotation scavenging system is preferably 1-5kg / t, specifically 1kg / t, 1.5kg / t, 2kg / t, 2.5kg / t, 3kg / t, 3.5kg / t, 3.8kg / t, 4kg / t, 4.5kg / t or 5kg / t.

[0075] In the above steps including the scavenging process provided by the present invention, after the flotation scavenging is completed, the obtained scavenging tailings pulp is preferably subjected to a second flotation scavenging to obtain a secondary scavenging concentrate foam and a secondary scavenging tailings pulp. The secondary scavenging concentrate foam is incorporated into the roughing concentrate foam; the secondary scavenging tailings pulp is concentrated and filtered to obtain a high-ash product. In the present invention, the secondary flotation scavenging is preferably carried out in the fourth flotation tank introduced above; the frother added in the secondary flotation scavenging is preferably 2# oil, and the addition amount of the frother in the secondary flotation scavenging system is preferably 100-500g / t, specifically 100g / t, 150g / t, 200g / t, 250g / t, 300g / t, 350g / t, 400g / t, 450g / t or 500g / t; the collector added in the secondary flotation scavenging is preferably kerosene, and the addition amount of the kerosene in the secondary flotation scavenging system is preferably 1-5kg / t, specifically 1kg / t, 1.5kg / t, 2kg / t, 2.5kg / t, 3kg / t, 3.5kg / t, 3.8kg / t, 4kg / t, 4.5kg / t or 5kg / t.

[0076] The resource recovery system and method provided by the present invention have simple process flow, low operating cost, good sorting product indicators, and good economic and environmental benefits. More specifically, the resource recovery system and method provided by the present invention have at least the following advantages:

[0077] 1) By using a dispersing agent to adjust the rheological properties of the filter cake mixed slurry system and the electrical properties of the material surface, the purpose of forced dispersion is achieved, creating favorable conditions for the next flotation process;

[0078] 2) Using oxidized oily wastewater to replace part of the collector in the flotation process greatly saves the cost of flotation reagents;

[0079] 3) The high-carbon product obtained by sorting has low ash content, high volatile matter and carbon content, good combustion characteristics, and a calorific value close to the calorific value of coal; and the high-carbon product has a large specific surface area, strong activity, easy to ignite and burn out, and can be directly put into boiler equipment and mixed with coal fuel for combustion;

[0080] 4) The high-ash product obtained by sorting has a high moisture content, fine particle size, large reserves, and certain potential activity. It can be directly used as a mineral admixture in the production of ready-mixed concrete. In addition, after drying, the high-ash product can also be used as a siliceous raw material for cement production, or as a cement admixture.

[0081] For the purpose of greater clarity, the invention is described in detail through the following embodiments.

[0082] Example 1

[0083] A kind of Figure 2 The coal chemical gasification filter cake resource system shown includes: a feed bin, a mixing barrel, an oxidation modifier, a first flotation tank, a second flotation tank, a third flotation tank, a fourth flotation tank, a first thickener, a first filter press, a second thickener and a second filter press.

[0084] Wherein, the feeding bin is provided with a feeding port and a discharging port;

[0085] The mixing barrel is provided with a gasification filter cake inlet, a modified wastewater inlet, a dispersing agent dosing port, a collecting agent dosing port, a foaming agent dosing port and a discharge port, and the gasification filter cake inlet of the mixing barrel is connected to the discharge port of the feeding bin through a feeder;

[0086] The oxidation modification machine is provided with an oily wastewater inlet and a discharge port, and the discharge port of the oxidation modification machine is connected to the modified wastewater inlet of the mixing barrel;

[0087] The first flotation tank is provided with a feed inlet, a concentrate outlet and a tailings outlet, and the feed inlet of the first flotation tank is connected to the discharge outlet of the stirring barrel;

[0088] The second flotation cell is provided with a feed inlet, a concentrate outlet and a tailings outlet, the feed inlet of the second flotation cell is connected to the concentrate outlet of the first flotation cell, and the tailings outlet of the second flotation cell is connected to the feed inlet of the first flotation cell;

[0089] The third flotation cell is provided with a feed inlet, a collector dosing inlet, a frother dosing inlet, a concentrate outlet and a tailings outlet. The feed inlet of the third flotation cell is connected to the tailings outlet of the first flotation cell, and the concentrate outlet of the third flotation cell is connected to the feed inlet of the second flotation cell.

[0090] The fourth flotation cell is provided with a feed inlet, a collector dosing inlet, a frother dosing inlet, a concentrate outlet and a tailings outlet. The feed inlet of the fourth flotation cell is connected to the tailings outlet of the third flotation cell, and the concentrate outlet of the fourth flotation cell is connected to the feed inlet of the second flotation cell.

[0091] The first flotation cell, the second flotation cell, the third flotation cell and the fourth flotation cell are all transmission-free flotation cells;

[0092] The first thickener is provided with a feed port, a flocculant dosing port, an overflow port and an underflow port. The feed port of the first thickener is connected to the concentrate outlet of the second flotation tank. The model of the first thickener is GX-6, the tank body inner diameter is 6000mm, the tank body height is 2300mm, and the sedimentation area is 27.6m 2 ;

[0093] The first filter press is provided with a feed inlet, a filtrate outlet and a solid material outlet. The feed inlet of the first filter press is connected to the underflow outlet of the first thickener. The model of the first filter press is Z100 / 1250-30U, and the filtration area is 100m 2 ;

[0094] The second thickener is provided with a feed port, a flocculant dosing port, an overflow port and an underflow port. The feed port of the second thickener is connected to the tailings outlet of the fourth flotation tank. The model of the second thickener is GX-6, the tank body inner diameter is 6000mm, the tank body height is 2300mm, and the sedimentation area is 27.6m 2 ;

[0095] The second filter press is provided with a feed inlet, a filtrate outlet and a solid material outlet. The feed inlet of the second filter press is connected to the underflow outlet of the second thickener. The model of the second filter press is Z100 / 1250-30U, and the filtration area is 100m 2 .

[0096] Example 2

[0097] A method for recycling coal chemical gasification filter cake is carried out in the recycling system described in Example 1, and the specific process is as follows:

[0098] 1) The gasification filter cake (water content of about 50wt%, carbon content of about 20wt%) is transported to the feeding bin by car, and then evenly transported to the mixing barrel by the feeder;

[0099] 2) Mixing oily wastewater (oil content 500-550 g / L) with methanol at a molar ratio of 5:1 between water and methanol, and then adding a mixed solution containing sodium hydroxide and aluminum oxide, wherein the amount of sodium hydroxide is 1.0-1.8 wt% of the mass of the oily wastewater, and the amount of aluminum oxide is 0.03-0.05 wt% of the mass of the oily wastewater, to oxidatively modify the oily wastewater to obtain oxidatively modified oily wastewater; then transporting the oxidatively modified oily wastewater to a stirring barrel, and controlling the solid content of the slurry in the stirring barrel to be about 15 wt%; adding 2.5 kg / t of HXAd-3# as a dispersing regulator to the stirring barrel based on the unit mass of the dry gasification filter cake, and simultaneously adding 700 g / t of 2# oil as a foaming agent and 6 kg / t of kerosene as a collector to obtain a slurry after slurry adjustment;

[0100] 3) flotation of the slurry after slurry adjustment, the flotation process is "one roughing + two scavenging + one concentrating", which is carried out in the first flotation tank (roughing), the third flotation tank (scavenging I), the fourth flotation tank (scavenging II) and the second flotation tank (concentrating) respectively; wherein, 500g / t of 2# oil as a frother and 4.2kg / t of kerosene as a collector are added in the roughing process, and 600g / t of 2# oil as a frother and 5.1kg / t of kerosene as a collector are added in the concentrating process; 350g / t of 2# oil as a frother and 3.8kg / t of kerosene as a collector are added in both scavenging processes; and at the same time, the scavenging process adds the collector, frother and other reagents according to the actual situation;

[0101] 4) After the slurry is subjected to flotation, the obtained concentrated ore foam is processed in the first thickener and the first filter press in sequence. During the processing, 20g / t of H66 flocculant is added to the first thickener to enhance the solid-liquid separation, and a high carbon product with a water content of less than 18wt% is obtained;

[0102] After the slurry is flotated after slurry adjustment, the scavenging II tailings slurry is processed in the second thickener and the second filter press in turn. During the processing, 15g / t of H66 flocculant is added to the second thickener to enhance the solid-liquid separation, and a high-ash product with a moisture content of less than 30wt% is obtained;

[0103] 5) The supernatant overflowing from the thickener and the filtrate produced by the filter press are used as recycled water and can be used according to specific circumstances.

[0104] The high-carbon product obtained in this embodiment has a carbon content of >40wt%, accounting for 25-30wt% of the product, and can be used for fuel blending; the high-ash product obtained has an ash content of >95wt%, accounting for 70-75wt% of the product, and can be used as a raw material for preparing concrete and other building materials.

[0105] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A coal chemical gasification filter cake resource system, comprising: A stirring barrel, on which a gasification filter cake inlet, a modified wastewater inlet, a dispersing agent dosing port, a collecting agent dosing port, a foaming agent dosing port and a discharge port are arranged; An oxidation modification machine is provided with an oily wastewater inlet and a discharge port, and the discharge port of the oxidation modification machine is connected to the modified wastewater inlet of the mixing barrel; A first flotation tank, wherein the first flotation tank is a transmission-free flotation tank, and a feed inlet of the first flotation tank is connected to a discharge outlet of the stirring barrel; a second flotation cell, wherein a feed port of the second flotation cell is connected to a concentrate outlet of the first flotation cell; a first thickener, wherein a feed port of the first thickener is connected to a concentrate outlet of the second flotation cell; a first filter press, wherein a feed port of the first filter press is connected to an underflow port of the first thickener; a second thickener, wherein a feed port of the second thickener is connected to a tailings outlet of the first flotation cell; A second filter press, wherein the feed port of the second filter press is connected to the underflow port of the second thickener.

2. The resource recycling system according to claim 1, characterized in that: Also included is a third flotation cell disposed between the tailings outlet of the first flotation cell and the feed inlet of the second thickener; The feed inlet of the third flotation cell is connected to the tailings outlet of the first flotation cell, the concentrate outlet of the third flotation cell is connected to the feed inlet of the second flotation cell, and the tailings outlet of the third flotation cell is connected to the feed inlet of the second thickener.

3. The resource recycling system according to claim 2, characterized in that: The third flotation tank is provided with a collector dosing port and a frother dosing port.

4. The resource recycling system according to claim 2, characterized in that: Also included is a fourth flotation cell disposed between the tailings outlet of the third flotation cell and the feed inlet of the second thickener; The feed inlet of the fourth flotation cell is connected to the tailings outlet of the third flotation cell, the concentrate outlet of the fourth flotation cell is connected to the feed inlet of the second flotation cell, and the tailings outlet of the fourth flotation cell is connected to the feed inlet of the second thickener.

5. The resource recycling system according to claim 4, characterized in that: The fourth flotation tank is provided with a collector dosing port and a frother dosing port.

6. The resource recycling system according to claim 1, characterized in that: It also includes a feeding bin for storing the gasified filter cake, and the discharge port of the feeding bin is connected to the gasified filter cake inlet of the mixing barrel.

7. The resource recycling system according to claim 1, characterized in that: The first thickener and the second thickener are both provided with a flocculant dosing port.

8. The resource recycling system according to any one of claims 1 to 7, characterized in that: The tailings outlet of the second flotation cell is connected to the feed inlet of the first flotation cell.

9. A method for recycling coal chemical gasification filter cake, comprising the following steps: a) mixing the gasification filter cake, the dispersion adjusting agent, the collector, the foaming agent and the oxidatively modified oily wastewater to obtain a slurry; In step a), the oxidatively modified oily wastewater is obtained by treating the oily wastewater in an oxidative modification machine, and the specific process of the treatment includes: mixing the oily wastewater with methanol and then performing oxidative modification in the presence of sodium hydroxide and aluminum oxide; b) performing flotation roughing on the slurry to obtain roughing concentrate foam and roughing tailings slurry; c) flotation separation of the rougher concentrate foam, and then concentrating and filtering the obtained concentrated concentrate foam to obtain a high-carbon product; d) concentrating and filtering the roughing tailings slurry to obtain a high-ash product; There is no order requirement for step c) and step d).

10. The resource recovery method according to claim 9, characterized in that: The step d) specifically comprises: d1) flotation scavenging the roughing tailings slurry to obtain scavenging concentrate foam and scavenging tailings slurry; d2) incorporating the scavenging concentrate foam into the roughing concentrate foam; and concentrating and filter-pressing the scavenging tailings slurry to obtain a high-ash product.

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