Comprehensive utilization system for biomass-containing sludge in sewage treatment process

Abstract

The utility model provides a comprehensive utilization system for biomass-containing sludge in a sewage treatment process, which relates to the technical field of sewage or sludge treatment and sequentially comprises a collection and temporary storage mechanism, an extrusion forming mechanism, a compression dehydration mechanism, a spiral dryer (18), a compression granulation mechanism, a sintering heat production mechanism and a crushing and grinding mechanism, a plurality of treatment functions are integrated into one system, so that the continuity of a sludge treatment process is realized, intermediate transfer links are reduced, and the treatment efficiency is greatly improved; particularly, in the pre-stage, the sludge is efficiently extruded into sheets through cooperation of gravity blanking and rotary extrusion, so that subsequent dehydration and treatment are facilitated, and the production efficiency is improved; the application range of the sludge is widened by dewatering, forming and granulating the sludge, the sludge can be used as a fuel, and residues after combustion can be conveniently used for manufacturing building materials, so that the resource utilization of the sludge is realized, the harm of the sludge to the environment is reduced, and considerable economic value is created.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of sewage or sludge treatment, and particularly relates to a comprehensive utilization system of biomass-containing sludge in a sewage treatment process. BACKGROUND

[0002] Municipal sludge and industrial sludge generated in a sewage treatment process usually contain a large amount of organic matter containing nitrogen and phosphorus, and also contain some potential pollutants such as heavy metals, and traditional landfill and incineration treatment have the risk of secondary pollution. With the tightening of environmental protection policies and technological progress, sludge resource utilization has become a new main approach, and its main directions include:

[0003] First, the sludge is treated and then used for agriculture and land use. The sludge is converted into fertilizer through composting, thermal drying and other technologies to supplement soil organic matter; however, due to the presence of heavy metals and other substances in the sludge, the conditions are relatively strict, and the treatment cost is high, so it is only suitable for sludge with low pollution level.

[0004] Second, the sludge is treated and then used for energy utilization. The sludge is subjected to anaerobic fermentation to generate methane (CH4) for power generation or heating; or the sludge is cracked under high-temperature anaerobic conditions to generate synthesis gas (CO+H2) and biochar. This is one of the better directions for utilization at present, and has great potential.

[0005] Also, the sludge can be used for building material utilization. The sludge is mixed into clay after preliminary treatment to produce bricks, or replaces part of the cement raw materials, and the mixing amount is usually ≤10%; or the sludge is sintered at high temperature to produce porous ceramsite for building insulation or water treatment filter material. This direction has a large amount of sludge to be accommodated, and is suitable for sludge with high heavy metal content, but the sintering energy consumption is large.

[0006] In addition, the sludge also has some high-value utilization ways, such as extraction of biopolymers and chemical precipitation of phosphorus, but the technical threshold is high, but the added value is significant, and is suitable for fine processing.

[0007] In summary, sludge resource utilization is the only way for sustainable development of the sewage treatment industry. According to the current technical level, energy utilization and building material utilization of sludge are more appropriate.

[0008] The following are typical cases of sludge building material utilization and resource utilization:

[0009] A sewage treatment plant sludge in a certain place makes environmental protection brick, adopts "dewatering solidification + broken soil + non-burning forming" process, treats the sludge with water content of 97% to 40%, and then improves oxygen utilization rate through nano-bubble aeration technology to make high-strength environmental protection brick. The environmental protection brick has a compressive strength of 15 MPa and a water permeability of 0.5 mm / s, meets the standard of "Permeable Pavement Brick and Permeable Pavement Panel" (GB / T 25993-2010), disposes 30,000 tons of sludge per year, replaces about 24,000 tons of natural sand and stone, and reduces 12,000 cubic meters of landfill.

[0010] A certain place generates electricity in cooperation with sludge, mixes municipal sludge with water content of 80% and coal in proportion, sends the sludge after high-temperature flue gas dewatering into a coal mill to realize mixed combustion and power generation, and uses the slag generated by incineration to make bricks. 250 tons of sludge are treated per day, 120,000 tons of carbon dioxide are reduced per year, the utilization rate of slag building materials is 90%, the power generation efficiency is improved by 15%, and the power generation capacity of each ton of sludge is 350 degrees, which meets 40% of the power demand of the plant area.

[0011] As can be seen from the above cases, sludge building materialization and resource utilization have gone towards large-scale application, and the main problems exist in the equipment. When the traditional dewatering equipment treats high-moisture sludge, the moisture content of the sludge cake after dewatering is still 60%-70%, which leads to high energy consumption in subsequent disposal; the sludge contains acidic substances and heavy metals, which causes serious equipment corrosion and high maintenance cost. Therefore, the key point of sludge recycling equipment is how to better reduce the moisture content of the sludge or make the sludge more suitable for dewatering. SUMMARY

[0012] In order to overcome the shortcomings of the prior art, the utility model provides a kind of comprehensive utilization system of sludge containing biomass in sewage treatment process, by the integration design of dewatering, drying, forming, pyrolysis and other functional components, optimize system structure, reduce volume and floor area, improve processing efficiency and product quality.

[0013] The application adopts the following technical scheme, a kind of comprehensive utilization system of sludge containing biomass in sewage treatment process, for the entire flow of sludge from dewatering to become building raw material;It includes collection and temporary storage mechanism, extrusion forming mechanism, compression dewatering mechanism, spiral dryer 18, compression granulation mechanism, sintering heat generating mechanism and crushing and grinding mechanism in turn;Sludge collection and temporary storage mechanism is connected with extrusion forming mechanism, and sludge is compressed to form ultra-thin sludge after preliminary water filtration, extrusion forming mechanism is connected with compression dewatering equipment by conveying belt, ultra-thin sludge enters compression dewatering equipment, then is connected with first spiral dryer 18 and second spiral dryer 18 in turn, the discharge port thereof is connected with granule compressor 19, granular sludge after forming participates in combustion of incinerator 20, and is sintered into block, finally enters ball mill 21 to be crushed and ground, and it is characterized by:

[0014] The collecting and temporary storing mechanism comprises a temporary storing hopper 1 suspended on the ground, a skeleton and a water filtering layer fixed on the skeleton, a water collecting tank 2 arranged below and a screen 3 arranged on the top; a spiral conveying pipe 5 is arranged at the bottom of the temporary storing hopper 1;

[0015] The extrusion forming mechanism is arranged at the side of the temporary storing hopper 1 and comprises two cylindrical mud storage pools 4, the upper ends of which are connected with the spiral conveying pipe 5, the upper part of the inside of the mud storage pool 4 is a storage space, a stirring shaft 6 is arranged at the center position, and a plurality of stirring blades are arranged on the shaft; a partition plate 7 is arranged at the lower part of the inside of the mud storage pool 4, and a rotating extrusion mechanism is arranged below the partition plate 7; a plurality of gravity feeding holes 8 are arranged on the outer ring of the partition plate 7 at intervals, and the holes are used for allowing the sludge above to fall from the holes by gravity; below each group of gravity feeding holes 8, there is a corresponding extrusion forming groove 9 embedded on the side wall of the mud storage pool 4; the extrusion forming groove 9 can protrude out of the side wall of the mud storage pool 4 and be embedded in the wedge-shaped groove arranged on the side wall of the mud storage pool 4; the inside of the wedge-shaped groove is provided with a thin slice sludge extrusion outlet 10 with a rectangular cross section, which penetrates through the side wall of the mud storage pool 4;

[0016] The top of the extrusion forming groove 9 is provided with a wedge-shaped block with arc surfaces on the inner and outer sides, the outer side arc surface is consistent with the arc of the side wall of the mud storage pool 4, and the inner side arc surface is consistent with the arc of the inner wall of the wedge-shaped groove arranged on the side wall of the mud storage pool 4; the end of the wedge-shaped groove is provided with an arc surface capable of accommodating the extrusion forming groove 9; the end of the side plate 11 is movably connected with the wedge-shaped groove through a rotating pin; in addition, the movable end of the side plate 11 is provided with an extension end plate 12, and a corresponding space for accommodating the extension end plate 12 is arranged on the side wall of the mud storage pool 4; when the extrusion forming groove 9 is embedded in the wedge-shaped groove, the extension end plate 12 is clamped into the corresponding space in the side wall of the mud storage pool 4 to keep sealing, and the extension end plate 12 and the side wall of the mud storage pool 4 are connected by a compression spring 13 arranged at the bottom of the space; after the force on the outside of the extrusion forming groove 9 disappears, the compression spring 13 pushes the extension end plate 12 to reset the extrusion forming groove 9.

[0017] At the vertical center of the space below the partition plate 7 of the mud storage pool 4, an independent rotating shaft is arranged, the rotating shaft penetrates through the bottom of the mud storage pool 4 and is connected with a driving motor, and a scraper 14 is arranged on the part of the rotating shaft remaining in the space below the partition plate 7 of the mud storage pool 4; the outer end of the scraper 14 keeps in contact with the side wall of the mud storage pool 4; the upper edge of the scraper 14 is vertically connected with a mud baffle 15 pointing to the advancing direction, the width of the mud baffle 15 is greater than the diameter of the feeding hole on the partition plate 7, and the lower edge of the scraper 14 is vertically connected with a support plate 16 on both sides; the mud baffle 15 keeps in contact with the lower surface of the partition plate 7, and the support plate 16 keeps in contact with the inner side of the bottom plate of the mud storage pool 4.

[0018] In addition, a conveyor belt is arranged below the sludge storage tank 4, which corresponds to the sheet sludge extrusion outlet 10, is respectively connected to the filter press 17, and a water collecting tank 2 and a sedimentation tank are arranged below the filter press 17, the discharge port of the filter press 17 is connected to the screw dryer 18, the discharge port of the screw dryer 18 is connected to the granular compressor 19 through a pipeline, the granulated sludge after forming participates in the combustion of the incinerator 20, and is sintered into blocks, and finally enters the ball mill 21 for crushing and grinding.

[0019] Preferably, the extrusion forming groove 9 protruding from the side wall of the sludge storage tank 4 and the wedge-shaped groove embedded in the side wall of the sludge storage tank 4 are both four in number, and are arranged at intervals of 90° around the rotating shaft.

[0020] Preferably, four groups of gravity feeding holes 8 are arranged on the outer ring of the partition plate 7 at intervals of 90°, and each group of gravity feeding holes 8 is distributed through the length direction of the extrusion forming groove 9.

[0021] Preferably, four scrapers 14 are arranged on the rotating shaft at intervals of 90°.

[0022] Preferably, the screw dryer 18 is arranged in two stages, and a second-stage screw dryer is arranged behind a first-stage screw dryer in series.

[0023] Preferably, the smoke outlet of the first-stage screw dryer and the second-stage screw dryer is provided with an electromagnetic white smoke removal device for treating smoke.

[0024] When the system is running, the following process is performed:

[0025] The sludge is concentrated in the temporary storage hopper 1, part of the sewage seeps out from the filter layer, and is collected, and then is transported to the sludge storage tank 4 of the extrusion forming mechanism through the spiral conveying pipe 5; the sludge is filtered through the screen 3 on the top of the sludge storage tank 4, falls into the sludge storage tank 4, and is mixed under the stirring blades to form a uniform state, and then falls into the extrusion forming groove 9 in the lower space of the sludge storage tank 4, that is, the extrusion forming groove 9, under the action of gravity, from the gravity feeding hole 8 arranged on the partition plate 7, with the rotation of the rotating shaft, the outer end of the scraper 14 contacts and gradually extrudes the whole extrusion forming groove 9 from the tip of the side plate 11 of the extrusion forming groove 9, and the extrusion forming groove 9 rotates along the rotating pin under the pressure of the scraper 14 and gradually enters the wedge-shaped groove arranged on the side wall of the sludge storage tank 4, until the whole is embedded; in the process, the gravity feeding hole 8 above the extrusion forming groove 9 is gradually blocked by the mud baffle 15 on the upper edge of the scraper 14 to stop feeding, and the sludge falling into the extrusion forming groove 9 is extruded in a sheet shape from the sludge extrusion outlet arranged on the side wall of the sludge storage tank 4 under the extrusion of the wedge-shaped side plate 11, with the rotation of the rotating shaft, the tube plate slides through the side plate 11 of the extrusion forming groove 9, the side plate 11 is restored to the original position under the action of the spring, and at the same time, the gravity feeding hole 8 blocked by the mud baffle 15 on the upper edge of the scraper 14 starts to feed again, preparing for the next extrusion forming;

[0026] The extruded sludge sheet is sent to the compression dewatering mechanism, and after being extruded and dewatered by the hydraulic rod, the obtained mud cake has a water content of less than 30%, and then is extruded and granulated, and the obtained sludge particles are used as incineration fuel or auxiliary fuel, and the waste residue generated by combustion automatically enters the ball mill 21 for crushing, and finally becomes building materials. Advantageous effects

[0027] The utility model discloses a plurality of processing functions are integrated in a system, realize the coherence of sludge treatment flow, reduce intermediate transfer link, improve the processing efficiency greatly, in the preposition stage, through the cooperation of gravity feeding and rotary extrusion, extrude the sludge into the sheet shape efficiently, it is convenient for subsequent dewatering and processing, improves production efficiency, and the sludge extruded into the foil is more favorable for subsequent dewatering operation, in the drying stage, sets up two -stage drying, ensures the low water content of sludge whole, and sets up electromagnetic white removing device at the first and second drying machine smoke outlet, effectively handles the smoke, reduces the pollution to the environment, through the sludge granulation, makes it convenient to burn, expands its use range, that is, can be used as fuel, and the residue after combustion can also be conveniently used to manufacture building materials, realizes the resource utilization of sludge, reduces the harm of sludge to the environment, also creates considerable economic value. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is the structural schematic diagram of the comprehensive utilization system of the sludge containing biomass in the sewage treatment process.

[0029] Figure 2 is the connection schematic diagram of the collecting and temporary storage mechanism and the extrusion molding mechanism.

[0030] Figure 3 is the structural schematic diagram of the extrusion molding mechanism.

[0031] Figure 4 is the top view of the extrusion molding groove.

[0032] Figure 5 is the structural schematic diagram of the scraper.

[0033] In the figure: temporary storage hopper 1, water collecting tank 2, screen 3, sludge storage tank 4, spiral conveying pipeline 5, stirring shaft 6, partition plate 7, gravity material dropping hole 8, extrusion molding groove 9, thin sludge extrusion outlet 10, side plate 11, extension end plate 12, compression spring 13, scraper 14, mudguard 15, support plate 16, filter press 17, spiral dryer 18, granular compressor 19, incinerator 20, ball mill 21. DETAILED DESCRIPTION

[0034] The specific embodiments of the present application are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended to illustrate and explain the present application, and are not intended to limit the present application.

[0035] As shown in Figures 1-5 , the comprehensive utilization system of biomass sludge in the sewage treatment process provided by the present application sequentially comprises a collecting and temporary storage mechanism, an extrusion molding mechanism, a compression and dehydration mechanism, a spiral dryer 18, a compression and granulation mechanism, a sintering and heat production mechanism, and a crushing and grinding mechanism. Each mechanism realizes continuous treatment of sludge through a conveying device (such as a conveying belt, a spiral pipeline, etc.), forming an integrated production line.

[0036] Key mechanisms and working principles

[0037] The collecting and temporary storage mechanism comprises a suspended temporary storage hopper 1, a filter layer is fixed on the skeleton of the temporary storage hopper 1, a spiral conveying pipeline 5 is arranged at the bottom, a screen 3 is installed at the top, and a water collecting tank 2 is arranged below; after the sludge is filtered through the screen 3, the sludge enters the temporary storage hopper 1, and the filtered sewage is collected by the water collecting tank 2. The spiral conveying pipeline 5 conveys the pretreated sludge to the extrusion molding mechanism.

[0038] The extrusion forming mechanism comprises two symmetrical cylindrical sludge storage tanks 4, which are communicated with a spiral conveying pipe 5 at the upper end; the sludge storage tank 4 is divided into upper and lower layers: the upper layer is a storage space, and a stirring shaft 6 and stirring blades are arranged at the center; the lower layer is divided by a partition plate 7, four groups of gravity feeding holes 8 are arranged on the partition plate 7 at intervals of 90 degrees; a rotating extrusion mechanism is arranged below the partition plate 7, and the rotating extrusion mechanism comprises four extrusion forming grooves 9 which are arranged at intervals of 90 degrees; each groove corresponds to a group of gravity feeding holes 8; the extrusion forming groove 9 is a wedge-shaped block, the outer arc surface of the wedge-shaped block is attached to the side wall of the sludge storage tank 4, the inner arc surface of the wedge-shaped block is embedded in a wedge-shaped groove, the end of the wedge-shaped block is movably connected with the wedge-shaped groove through a rotating pin, and the wedge-shaped block is reset through a compression spring 13 and an extension end plate 12; four scrapers 14 are arranged on the vertical central shaft, the outer end of the scraper 14 is in contact with the side wall of the sludge storage tank 4, a mud guard 15 is arranged on the upper edge of the scraper 14, and a supporting plate 16 is arranged on the lower edge of the scraper 14.

[0039] Workflow:

[0040] ① After the sludge is uniformly mixed by the stirring shaft 6, the sludge enters the extrusion forming groove 9 through the gravity feeding hole 8;

[0041] ② The rotating shaft drives the scraper 14 to rotate, the outer end of the scraper 14 extrudes the extrusion forming groove 9, so that the extrusion forming groove 9 is embedded in the wedge-shaped groove, and the sludge is extruded into a sheet shape and discharged from the sheet sludge extrusion outlet 10;

[0042] ③ The compression spring 13 pushes the extension end plate 12, so that the extrusion forming groove 9 is reset, the gravity feeding hole 8 is reopened, and the feeding is recycled.

[0043] The compression dewatering and drying mechanism, the extruded sludge sheet enters the filter press 17 through the conveying belt, and the filter press is provided below with a water collecting tank 2 and a sedimentation tank; the filter-pressed mud cake enters two-stage screw dryers 18, the first-stage and second-stage dryers are connected in series, and electromagnetic white removal devices are arranged at the smoke outlets; the filter press 17 reduces the water content of the mud cake to below 30%, the two-stage drying further reduces the water content, and the electromagnetic white removal devices purify the flue gas.

[0044] The granulation, sintering and crushing mechanism, the dried sludge is formed into particles by the particle compactor 19, the granular sludge is burned in the incinerator 20, the generated waste residue is crushed by the ball mill 21 to become a building material; the sludge particles are used as fuel or auxiliary fuel, and the combustion residue is recycled, so that the closed-loop treatment is realized.

[0045] The above only describes preferred embodiments of the present application, and it should be pointed out that, for ordinary skilled persons in the technical field, some improvements can be made without departing from the principles of the present application, and these improvements should also be regarded as the protection scope of the present application.

Claims

1. A comprehensive utilization system of biomass-containing sludge in a sewage treatment process, for the whole process from dewatering to becoming a building raw material; sequentially comprising a collecting and temporarily storing mechanism, an extrusion molding mechanism, a compression dewatering mechanism, a screw dryer (18), a compression granulating mechanism, a sintering heat generating mechanism, and a crushing and grinding mechanism, characterized in that: the collecting and temporarily storing mechanism comprises a temporarily storing hopper (1) suspended on the ground, comprising a framework and a filter layer fixed on the framework, a water collecting tank (2) is arranged below, and a screen (3) is arranged on the top; a spiral conveying pipeline (5) is arranged at the bottom of the temporarily storing hopper (1). The extrusion molding mechanism is arranged on the side of the temporarily storing hopper (1), comprising two cylindrical sludge storage tanks (4), the upper ends of which are connected with the spiral conveying pipeline (5), the upper part inside the sludge storage tank (4) is a storage space, a stirring shaft (6) is arranged at the center position, and a plurality of stirring blades are arranged on the shaft; a partition plate (7) is arranged at the lower part inside the sludge storage tank (4), and a rotating extrusion mechanism is arranged below the partition plate (7); a plurality of gravity material falling holes (8) are arranged on the outer ring of the partition plate (7) at intervals, and the holes are used for the falling of the sludge under its own gravity; each group of gravity material falling holes (8) corresponds to an extrusion molding groove (9) embedded on the side wall of the sludge storage tank (4), the extrusion molding groove (9) can protrude out of the side wall of the sludge storage tank (4) and be embedded in the wedge-shaped groove arranged on the side wall of the sludge storage tank (4), and a thin slice sludge extrusion outlet (10) with a rectangular cross section is arranged in the wedge-shaped groove. The top opening of the extrusion molding groove (9) is a wedge-shaped block with arc surfaces on the inner and outer sides, the outer side arc surface is consistent with the arc of the side wall of the sludge storage tank (4), and the inner side arc surface is consistent with the arc of the inner wall of the wedge-shaped groove arranged on the side wall of the sludge storage tank (4); the end of the wedge-shaped groove is provided with an arc surface capable of accommodating the extrusion molding groove (9) which needs to be freely in and out; the end of the side plate (11) is movably connected with the wedge-shaped groove through a rotating pin; in addition, the movable end of the side plate (11) is provided with an extension end plate (12), and a corresponding space for accommodating the extension end plate (12) is arranged on the side wall of the sludge storage tank (4); when the extrusion molding groove (9) is embedded in the wedge-shaped groove, the extension end plate (12) is clamped into the corresponding space in the side wall of the sludge storage tank (4) to keep sealing, and a compression spring (13) is arranged at the bottom of the space to connect the extension end plate (12) and the side wall of the sludge storage tank (4); after the force on the outer side of the extrusion molding groove (9) disappears, the compression spring (13) pushes the extension end plate (12) to reset the extrusion molding groove (9) as a whole.

2. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 1, characterized in that, ​ 3. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 1 or 2, characterized in that, In the vertical center of the space below the partition plate (7) of the sludge storage tank (4), a separate rotating shaft is arranged, which penetrates the bottom of the sludge storage tank (4) and is connected with a driving motor, and a scraper (14) is installed on the part of the rotating shaft remaining in the space below the partition plate (7) of the sludge storage tank (4); the outer end of the scraper (14) keeps in contact with the side wall of the sludge storage tank (4); the upper edge of the scraper (14) is vertically connected with a mud baffle (15) pointing to the advancing direction, the width of which is greater than the diameter of the material falling hole on the partition plate (7), and the lower edge of the scraper (14) is vertically connected with a support plate (16) on both sides; the mud baffle (15) keeps in contact with the lower surface of the partition plate (7), and the support plate (16) keeps in contact with the inner side of the bottom plate of the sludge storage tank (4); In addition, a conveying belt is arranged below the sludge storage tank (4), which corresponds to the sheet sludge extrusion outlet (10), is connected to a filter press (17) respectively, and a water collecting tank (2) and a sedimentation tank are arranged below the filter press (17), the discharge port of the filter press (17) is connected with a screw dryer (18), and the discharge port of the screw dryer (18) is connected to a particle compressor (19) through a pipeline.

4. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 1, characterized by The number of the extrusion forming grooves (9) and the wedge-shaped grooves embedded in the side wall of the sludge storage tank (4) corresponding to them is four, which are arranged at an interval of 90° with the rotating shaft as the center.

5. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 1, characterized in that, Four groups of gravity material falling holes (8) are arranged on the outer ring of the partition plate (7) at an interval of 90°, and each group of gravity material falling holes (8) is distributed through the length direction of the extrusion forming groove (9).

6. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 1, characterized in that, The screw dryer (18) is arranged in two stages, which are a primary screw dryer and a secondary screw dryer arranged behind and connected in series with the primary screw dryer.

7. The system for comprehensive utilization of biomass-containing sludge in a sewage treatment process according to claim 6, characterized by The smoke outlet of the primary screw dryer and the secondary screw dryer is provided with an electromagnetic white smoke removal device for treating smoke.

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