CN112142286A - Geotextile for dewatering and curing sludge and slurry and processing technology thereof - Google Patents

Abstract

The invention relates to the technical field of sludge and slurry dehydration and solidification treatment, in particular to geotextile for sludge and slurry dehydration and solidification and a processing technology thereof. The geotextile is woven by warp yarns and weft yarns, and the weight of each square meter is 150-250 g; the warp yarn is round and flat yarn, and the width of the yarn is 0.5-1 mm; the weft is an open silk screen, and the width of the silk is 1.7-2.3 mm; and in each 10cm multiplied by 10cm geotextile, the number of warp threads is 72-100, and the number of weft threads is 40-80. The geotextile is sewn into a tube bag, and the tube bag has excellent water permeability and proper pore diameter, so that two problems of dehydration and slurry leakage in the dehydration and solidification treatment of sludge and slurry are solved. The geotextile plays a role in the dehydration and solidification treatment of the sludge and the slurry through the sewn pipe bag. The geotextile is prepared by the steps of mixing, extruding, drawing and weaving, the processing steps are simple and convenient to operate, the prepared geotextile is light and thin, sludge or slurry can be conveniently and rapidly dehydrated and solidified, and the geotextile has the characteristics of strong soil retention capacity and low production cost.

Description

Geotextile for dewatering and curing sludge and slurry and processing technology thereof

Technical Field

The invention relates to the technical field of sludge and slurry dehydration and solidification treatment, in particular to geotextile for sludge and slurry dehydration and solidification and a processing technology thereof.

Background

The sludge is a flocculent or honeycomb structure formed by deposition of fine particles such as clay minerals and the like in slow flowing water environments such as oceans or lake regions and the like under the action of inter-particle electrostatic force and molecular attraction, and the water content of the sludge is 1.2-2.0 times of the water content of a liquid limit. The mud is a mixed liquid formed by the sludge diffused in water, and the water content of the mud is larger than that of the sludge. Therefore, the sludge and the mud are in a flowing state, almost have no strength and are difficult to be directly used for engineering, and further a great deal of land resources are wasted.

At present, the domestic resource utilization of the sludge mainly comprises methods such as mechanical treatment, hydraulic filling and land reclamation, physical dehydration, heat treatment, curing agent treatment and the like. The geotextile is an indispensable processing tool in the dehydration and solidification operation process of the sludge and the slurry and is used for separating the silt and the water in the sludge or the slurry.

However, when the existing geotextile dehydrates the silt or the slurry, the silt and the slurry have certain water storage performance, so if the permeable gap of the geotextile is small, the water in the silt and the slurry cannot be removed in time, and the originally separated water can be mixed with the silt again; if the gaps of the geotextile for water penetration are large, soil in the sludge and the slurry can be lost. Therefore, the research and development of a novel geotextile with high dehydration and solidification efficiency and strong soil retention capacity and a processing technology thereof are technical problems which are urgently needed to be solved at present.

Disclosure of Invention

Aiming at the defects in the prior art, one of the purposes of the invention is to provide the geotextile for dewatering and curing the sludge and the slurry, which has novel structure, excellent dewatering and curing efficiency and soil body retention capacity and can be better suitable for quick dewatering and curing of the sludge and the slurry.

The invention also aims to provide a processing technology of the geotextile for dewatering and curing the sludge and the slurry, which has the advantages of simple process and convenient operation and is convenient for the mass production of the geotextile.

The above object of the present invention is achieved by the following technical solutions:

the geotextile for dewatering and curing the sludge and the slurry is woven by warp yarns and weft yarns, and the weight of each square meter is 150-250 g; the warp yarn is a round flat yarn, and the width of the yarn is 0.5-1 mm; the weft is an open silk screen, and the width of the silk is 1.7-2.3 mm; and in each 10cm multiplied by 10cm geotextile, the number of warp threads is 72-100, and the number of weft threads is 40-80.

The geotechnical cloth of this application is woven by the warp and weft of above-mentioned specification and is formed, and its novel structure for geotechnical cloth's clearance is moderate, not only can realize the quick dehydration solidification of silt and mud, can also effectively remain the soil body, reduces the loss of the soil body, the quick dehydration solidification who is applicable to silt and mud that can be better. In addition, the weight of the geotextile per square meter is obviously less than that of the geotextile with the same soil retention capacity in the market (360-420 g/m 2), so that the raw material consumption of the geotextile is obviously less than that of the geotextile in the market, and the production cost of the geotextile can be effectively reduced during batch production.

The present invention in a preferred example may be further configured to: the warp yarns and the weft yarns comprise the following components in parts by weight: 91-95 parts of wire-drawing PP, 2-4 parts of PE, 2-4 parts of black master batch, 0.2-0.5 part of anti-ultraviolet agent and 0.2-0.5 part of antioxidant.

By adopting the technical scheme, the drawing-grade PP serves as a main material, the PE can increase the mechanical strength of the drawing-grade PP, the black master batch is used for adjusting the color of the geotextile, and the uvioresistant agent and the antioxidant can effectively guarantee the uvioresistant performance and the oxidation resistance of the geotextile, so that the service life of the geotextile is prolonged.

The present invention in a preferred example may be further configured to: the melt index of the drawing grade PP is 5-8g/10min, and the density is 0.9-1.0g/cm 3.

The present invention in a preferred example may be further configured to: the PE is HDPE.

By adopting the technical scheme, when the melt index of the drawing-grade PP is 5-8g/10min and the density is 0.9-1.0g/cm3, the drawing-grade PP is matched with HDPE for use, so that the possibility of fracture of the extrusion material can be effectively reduced in the drawing process of the prepared extrusion material, and the prepared geotextile has good structural strength.

The present invention in a preferred example may be further configured to: the uvioresistant agent is formed by compounding UV-328 and UV-770 according to the weight ratio of 1: 1.

The present invention in a preferred example may be further configured to: the antioxidant is compounded by an antioxidant 1010 and an antioxidant 168 according to the weight ratio of 2: 3.

By adopting the technical scheme, in the composition proportion, the anti-ultraviolet agent compounded by UV-328 and UV-770 in a weight ratio of 1:1 and the antioxidant compounded by the antioxidant 1010 and the antioxidant 168 in a weight ratio of 2:3 are selected, so that the anti-ultraviolet agent has more excellent anti-ultraviolet performance and oxidation resistance compared with other anti-ultraviolet agents and antioxidants.

By adopting the technical scheme, on the basis of the components of the base cloth layer, the antioxidant 1010 and the antioxidant 168 are compounded according to the weight ratio of 2:1, so that the antioxidant performance of the geotextile can be effectively improved.

The present invention in a preferred example may be further configured to: the warp yarns and the weft yarns also comprise 3-8 parts of polyvinyl alcohol.

The present invention in a preferred example may be further configured to: the polymerization degree of the polyvinyl alcohol is 300-450.

By adopting the technical scheme, the polyvinyl alcohol can increase the hydrophilic property of PP on one hand, and plays a role of an adhesive on the other hand, so that the PE and the black master batch are uniformly and stably dispersed in the PP, and the prepared geotextile has good dehydration curing property and mechanical property. Wherein, the polyvinyl alcohol with the polymerization degree of 300-450 is selected, and the prepared geotextile has more excellent dehydration and solidification performances, so the polyvinyl alcohol is further preferred.

The present invention in a preferred example may be further configured to: the warp and weft also comprise 2-3 parts of hydrophilic antifouling agent.

The present invention in a preferred example may be further configured to: the hydrophilic antifouling agent is a GH-701 antifouling agent.

By adopting the technical scheme, silt in the silt or mud is difficult to be retained on the film formed with the GH-701, and the GH-701 antifouling agent is selected to enable the prepared geotextile to have excellent antifouling performance on the basis of the components of the base cloth layer, so that the silt is easily flushed clean.

The second aim of the invention is realized by the following technical scheme:

a processing technology of geotextile for dewatering and curing sludge and slurry comprises the following steps:

firstly, premixing: respectively weighing wire drawing PP, PE and black master batch according to the set weight parts, and mixing to obtain a premix;

② extruding: putting the premix into a double-screw extruder, controlling the temperature of the front section at 180-;

thirdly, drawing wire: respectively putting the extruded materials into a warp wire drawing machine and a weft wire drawing machine to respectively prepare warp wires and weft wires;

fourthly, knitting: and (3) taking the warp yarns and the weft yarns as raw materials, collecting, finishing and knitting by a warping machine, and then knitting by a flat knitting machine to obtain the final geotextile.

By adopting the technical scheme, the wire-drawing PP, the PE and the black masterbatch are premixed and then melted by the extruder, so that the three materials are rapidly and uniformly mixed. The anti-ultraviolet agent, the antioxidant and other processing aids are added at the rear section of the double-screw extruder, and the temperature is relatively low, so that the premix is in a molten state, the chemical stability of the anti-ultraviolet agent, the antioxidant and other processing aids is ensured, and the premix can better play a role. And then, by drawing and weaving, the prepared geotextile is light and thin, is convenient for sludge or slurry to be quickly dehydrated and solidified, and has the characteristics of simple processing steps and convenience in operation.

In summary, the invention includes at least one of the following beneficial technical effects:

1. the geotextile is formed by weaving warp yarns and weft yarns with specific specifications, has a novel structure, has excellent dehydration and solidification efficiency and soil body retention capacity, is low in production cost, and can be well suitable for rapid dehydration and solidification of sludge and slurry;

2. in the geotextile, the warp yarns and the weft yarns are made of specific components, so that the geotextile has excellent dehydration curing efficiency, mechanical strength, ultraviolet resistance and ageing resistance;

3. the geotextile of this application adopts the compounding, extrudes, the step preparation of wire drawing and weaving to form, and the geotextile of making is frivolous and be convenient for silt or mud to dewater the solidification fast, has the characteristics that the processing step is simple, the operation of being convenient for.

Drawings

Fig. 1 is a process diagram for preparing geotextiles for dewatering and curing sludge and slurry.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

1. Raw materials

PP: by taking drawing grade PP and common PP as examples, the drawing grade PP is purchased from Exxon Mobil 7033E, the melt index is 5-8g/min, and the density is 0.9-1.0g/cm 3; ordinary PP is available from Xiaoxing R701 of Korea, has a melt index of 18-20g/min and a density of 0.9-1.0g/cm 3;

PE: taking HDPE (high density polyethylene) and LDPE (low density polyethylene) as examples, HDPE is purchased from Exxon Mobil HMA-025, and LDPE is purchased from Michelson No. 2426H;

black masterbatch: purchased from Hebei Derun rubber and plastic materials Co., Ltd, and the product number is Derun mother black master 3030;

polyvinyl alcohol: taking polyvinyl alcohol a and polyvinyl alcohol b as examples, polyvinyl alcohol a is purchased from Zhenzhou Binsheng chemical products, Inc., and the polymerization degree is 300-; polyvinyl alcohol b is purchased from Zhenzhou sanden chemical products, Inc., and has a polymerization degree of 450-;

hydrophilic antifouling agent: taking GH-701 antifouling agent and antifouling auxiliary agent 70 as examples, the GH-701 antifouling agent is purchased from Dajin Industrial Co., Ltd, and the antifouling auxiliary agent 70 is purchased from Shenzhen West science and technology Co., Ltd, with the model number of 70 and the average particle size of 1 μm.

2. Examples 1 to 4 and comparative examples 1 to 3

2.1 example 1

A geotextile for dewatering and curing sludge and slurry is woven by warp yarns and weft yarns, and the weight of each square meter is 150 g; the warp yarn is a round flat yarn, and the width of the yarn is 1.0 mm; the weft is an open silk screen, and the width of the silk is 2.3 mm; and in each 10cm multiplied by 10cm geotextile, the number of warp threads is 72, and the number of weft threads is 40. The section of the flat round wire vertical to the axis is elliptical, and the wire width is the short diameter length of the ellipse; the section of the silk opening net vertical to the axial line is circular, and the silk width is the diameter and the length of the circle.

The warp yarns and the weft yarns comprise the following components in parts by weight: 91 parts of wire-drawing PP, 4 parts of HDPE, 3 parts of black master batch, 0.5 part of uvioresistant agent, 0.5 part of antioxidant, 3 parts of polyvinyl alcohol a and 12 parts of GH-7012.

Wherein the anti-ultraviolet agent is formed by compounding UV-328 and UV-770 according to the weight ratio of 1:1, and the antioxidant is formed by compounding antioxidant 1010 and antioxidant 168 according to the weight ratio of 2: 3.

The processing technology of the geotextile for dewatering and curing the sludge and the slurry, which is shown in figure 1, comprises the following steps:

firstly, premixing: respectively weighing wire drawing grade PP, HDPE and black master batch according to the set weight parts, and mixing to obtain a premix;

② extruding: putting the premix into a double-screw extruder, controlling the temperature of the front section to be 170 ℃, the temperature of the middle section to be 180 ℃ and the temperature of the rear section to be 155 ℃, respectively weighing the uvioresistant agent, the antioxidant, the polyvinyl alcohol a and the GH-701 according to the set weight parts, and putting the weighed uvioresistant agent, the antioxidant, the polyvinyl alcohol a and the GH-701 into the rear section of the double-screw extruder to obtain a molten extruded material;

thirdly, drawing wire: respectively putting the extruded materials into a warp wire drawing machine and a weft wire drawing machine to respectively prepare warp wires and weft wires;

fourthly, knitting: and (3) taking the warp yarns and the weft yarns as raw materials, collecting, finishing and knitting by a warping machine, and then knitting by a flat knitting machine to obtain the final geotextile.

2.2, examples 2 to 4

Examples 2-4 the specifications of the warp and weft were adjusted on the basis of the process of example 1, see table 1 below for specific adjustments.

Table 1 specification parameter table for geotextiles of examples 1-4

Example 1 example 2 example 3 example 4

Weight per square meter/g 150182203250

Width of warp yarn/mm 1.00.50.81.0

Weft width/mm 2.32.01.72.0

Number of warp threads/root 728010090

Number of weft threads/root 40556080

2.3, comparative example 1

In comparative example 1, the geotextile has a weight of 98g per square meter, the warp yarns and the weft yarns have the same specification, are round and flat yarns, the yarn width is 1.0mm, and the number of the warp yarns is 72 and the number of the weft yarns is 40 in each geotextile with the thickness of 10cm × 10 cm.

2.4, comparative example 2

In comparative example 2, the geotextile has a weight of 261g per square meter, the warp and weft have the same specification, both are open nets, the width of the silk is 2.0mm, and in the geotextile of 10cm × 10cm, the number of the warp is 80 and the number of the weft is 55.

2.5, comparative example 3

Available from Texas Huixin geotechnical materials Co., Ltd, cat # 5461 and PP.

3. Performance testing

The geotextiles prepared in the above examples 1 to 4 and comparative examples 1 to 3 were subjected to the following performance tests, and the test results are shown in the following table 2.

3.1, dehydration curing performance: fixing 50cm × 50cm geotextile on a frame to form a net bag, wherein one side coated with the water repellent faces downwards, and stirring the geotextile with the weight ratio of mud: water = 1: 10 preparing mud liquid, pouring 1kg of mud liquid into a net bag formed by geotextile, and recording the time for draining water in the net bag.

3.2, soil retention performance: fixing 50cm × 50cm geotextile on a frame to form a net bag, wherein one side coated with the water repellent faces downwards, and stirring the geotextile with the weight ratio of mud: water = 1: 10, preparing mud liquid, pouring 1kg of mud liquid into a net bag formed by geotextile, drying the mud material after water filtration, and calculating mud material loss rate% = (mud material addition amount-mud material residual amount)/mud material addition amount multiplied by 100%.

3.3, mechanical property: and (3) calculating the average value of tearing strength of the geotextile by adopting a tensile machine for a strip tensile test, wherein the tensile rate is 100mm/min, and the sample is 76cm multiplied by 200 cm.

Table 2 test results of the geotextiles of examples 1 to 4 and comparative examples 1 to 3

Drainage time/min mud loss rate/% tearing strength/N

Example 152.3715

Example 261.9697

Example 352.0724

Example 481.6732

Comparative example 1138.7580

Comparative example 2911.2625

Comparative example 3212.2670

The combination is shown in table 2, can obtain the geotechnological cloth of this application for the geotechnological cloth of comparative example, not only can realize the quick dehydration solidification of silt and silt, can also have the loss that reduces the soil body, has excellent mechanical properties simultaneously concurrently. In addition, the geotextile has relatively light weight in unit area, can effectively reduce the production cost of enterprises, and is convenient to be widely applied to the technical field of dehydration and solidification treatment of slurry of cast-in-situ bored piles in rivers (lakes), construction projects, sludge of sedimentation tanks in sewage plants (industrial enterprises), tailing slurry and the like.

4. Examples 5 to 14

Examples 5-14 the parameters of the warp and weft components were adjusted based on the method of example 1, see table 3 below.

Table 3 table of composition parameters for geotextiles of examples 1, 5-14

5. Performance detection

The geotextiles of example 1 and examples 5 to 12 were subjected to the following performance tests, and the test results are shown in table 4 below.

5.1, dehydration curing performance: fixing 50cm × 50cm geotextile on a frame to form a net bag, wherein one side coated with the water repellent faces downwards, and stirring the geotextile with the weight ratio of mud: water = 1: 10 preparing mud liquid, pouring 1kg of mud liquid into a net bag formed by geotextile, and recording the time for draining water in the net bag.

5.2, mechanical property: and (3) calculating the average value of tearing strength of the geotextile by adopting a tensile machine for a strip tensile test, wherein the tensile rate is 100mm/min, and the sample is 76cm multiplied by 200 cm.

5.3, ultraviolet resistance: and (3) adopting an ultraviolet-resistant performance aging box for the geotextile, irradiating for 72h under the condition of UV =380nm, and calculating the retention rate of tearing strength of the geotextile.

5.4, oxidation resistance: and (3) adopting an ageing oven for the oxidation resistance of the geotextile at the temperature of 250 ℃ for 14 days, and calculating the retention rate of the tearing strength of the geotextile.

5.5, antifouling property: and (4) washing away the silt on the surface of the geotextile after the test 1 is finished by using clear water, and observing the condition of the silt remained on the geotextile.

Table 4 test results of the geotextiles of examples 1, 5 to 12

Tear strength at drainage/min/tear strength retention by N (ultraviolet)/tear strength retention by% tear strength by Oxidation/% antifouling Property

Example 157159897 silt-free

Example 557109897 silt-free

Example 657129798 silt-free

Example 756909897 silt-free

Example 876819797 silt-free

Example 957128991 silt-free

Example 1057139486 silt-free

Example 1187159897 silt-free

Example 12117159797 silt-free

Example 1357149798A little silt

Example 1457149897 heavy silt

With reference to table 4, the test results of examples 1 and 5-6 are similar, and therefore, the geotextiles obtained according to the composition parameters of the present application have the characteristics of high dehydration curing efficiency, strong soil retention capacity, high strength, excellent ultraviolet resistance and oxidation resistance, and strong antifouling property.

Comparing the detection results of the embodiment 1 and the embodiments 7 to 8, it can be obtained that when the melt index of the drawing-grade PP is 5 to 8g/10min and the density is 0.9 to 1.0g/cm3, the drawing-grade PP is used in combination with HDPE, so that the possibility of fracture of the extruded material can be effectively reduced, and the prepared geotextile has good structural strength.

Comparing the detection results of the embodiment 1 and the embodiments 9-10, the ultraviolet resistant agent compounded by UV-328 and UV-770 according to the weight ratio of 1:1 and the antioxidant compounded by the antioxidant 1010 and the antioxidant 168 according to the weight ratio of 2:3 can be obtained, and compared with other ultraviolet resistant agents and antioxidants, the ultraviolet resistant agent and the antioxidant have more excellent ultraviolet resistance and oxidation resistance.

Comparing the detection results of the embodiment 1 and the embodiments 11-12, it can be obtained that the polyvinyl alcohol with the polymerization degree of 300-450 is selected, and the drainage time of the geotextile prepared by the polyvinyl alcohol is short, so that the geotextile has more excellent dehydration and solidification performances.

Comparing the detection results of the embodiment 1 and the embodiments 13 to 14, it can be seen that the GH-701 antifouling agent selected for use in the application can enable the prepared geotextile to have more excellent antifouling performance compared with other antifouling agents, and the silt on the geotextile can be conveniently washed clean.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims (10)

1. The geotextile for dewatering and curing the sludge and the slurry is characterized by being woven by warp yarns and weft yarns, wherein the weight of each square meter is 150-250 g; the warp yarn is a round flat yarn, and the width of the yarn is 0.5-1 mm; the weft is an open silk screen, and the width of the silk is 1.7-2.3 mm; and in each 10cm multiplied by 10cm geotextile, the number of warp threads is 72-100, and the number of weft threads is 40-80.

2. The geotextile for dewatering and curing sludge and mud according to claim 1, wherein the warp yarns and the weft yarns comprise the following components in parts by weight: 91-95 parts of wire-drawing PP, 2-4 parts of PE, 2-4 parts of black master batch, 0.2-0.5 part of anti-ultraviolet agent and 0.2-0.5 part of antioxidant.

3. The geotextile for dewatering and curing sludge and mud of claim 2, wherein the drawing grade PP has a melt index of 5 to 8g/10min and a density of 0.9 to 1.0g/cm 3.

4. The geotextile for dewatering and curing sludge and mud of claim 2, wherein the ultraviolet resistant agent is prepared by compounding UV-328 and UV-770 in a weight ratio of 1: 1.

5. The geotextile for dewatering and curing sludge and mud of claim 2, wherein the antioxidant is prepared by compounding antioxidant 1010 and antioxidant 168 according to a weight ratio of 2: 3.

6. The geotextile for dewatering and curing sludge and mud of claim 2, wherein the warp yarns and the weft yarns further comprise 3 to 8 parts of polyvinyl alcohol.

7. The geotextile for dewatering and curing sludge and mud of claim 6, wherein the degree of polymerization of the polyvinyl alcohol is 300-450.

8. The geotextile for dewatering and curing sludge and mud of claim 2, wherein the warp yarns and the weft yarns further comprise 2 to 3 parts of a hydrophilic antifouling agent.

9. The geotextile for dewatering and curing sludge and mud of claim 8, wherein the hydrophilic antifouling agent is a GH-701 antifouling agent.

10. A process for manufacturing geotextiles used for dewatering and curing sludge and slurry as claimed in any of claims 1 to 9, comprising the steps of:

firstly, premixing: respectively weighing wire drawing PP, PE and black master batch according to the set weight parts, and mixing to obtain a premix;

② extruding: putting the premix into a double-screw extruder, controlling the temperature of the front section at 180-;

thirdly, drawing wire: respectively putting the extruded materials into a warp wire drawing machine and a weft wire drawing machine to respectively prepare warp wires and weft wires;

fourthly, knitting: and (3) taking the warp yarns and the weft yarns as raw materials, collecting, finishing and knitting by a warping machine, and then knitting by a flat knitting machine to obtain the final geotextile.

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