TWI649274B - A solid carbon source, a bioreactor having the same and a method of wastewater treatment - Google Patents

Abstract

A solid carbon source includes: a plurality of strip units having at least one turning portion, each of the strip units forming a limiting portion by the turning portion, and at least one of the limiting portions of any one of the strip units is disposed The strip unit, wherein the plurality of strip units are integrated into a skeleton structure; and a plurality of gaps are formed between any two strip units for gas or liquid passage, wherein each strip unit is formed The material is a composite material having a density system greater than 0.9 g/cm ³ . The present disclosure provides a method comprising a bioreactor having the solid carbon source and treating the wastewater with the solid carbon source.

Description

 Solid carbon source, bioreactor having the solid carbon source, and method for treating wastewater by the solid carbon source  

The present disclosure relates to a solid carbon source for treating wastewater, and more particularly to a solid carbon source, a bioreactor and a method for treating wastewater which are suitable for treating wastewater containing nitrogen nitrate.

With the improvement of living standards and awareness of environmental protection, the emphasis on wastewater and sewage treatment is increasing. Generally, treatment methods for wastewater containing nitrate nitrogen (NO ₃ -N) are classified into chemical treatment methods (such as ion exchange, membrane reverse osmosis, electrodialysis, and treatment of zero-valent metals) and biological treatment methods ( For example, the activated sludge method, and the chemical treatment method usually has the problem of secondary pollution. The biological treatment method (biological nitrogen removal treatment program) can convert the nitrate nitrogen in the water into non-polluting nitrogen emissions, so as to avoid secondary Pollution.

The existing biological treatment technology for ammonia-containing wastewater is most widely used in the traditional nitrification and denitrification process. The nitrification and denitrification procedure utilizes nitrifying bacteria or nitrosating bacteria to oxidize ammonia nitrogen to nitrate or nitrite in an aerobic environment. Nitrogen or nitrite is then reduced to nitrogen in an anaerobic environment by denitrifying bacteria. However, the denitrifying bacteria are heterotrophic bacteria, and a certain amount of carbon source is needed as a source of energy in the wastewater. If there is no sufficient carbon source in the wastewater, it needs to be added separately.

However, the method of providing a carbon source now uses an organic solvent such as methanol as an externally added carbon source, which is flammable and volatile, and often generates public security problems, and in order to maintain the carbon source required for microorganisms in the denitrification process, In the current treatment method, methanol is usually added in excess, which not only consumes too much carbon source cost, but also causes the COD value of the outflow water to be too high, and an aerobic biological treatment system for treating the outflow water is added to remove or Reducing residual organic matter (such as excess carbon source) can meet the discharge water standard.

Therefore, how to provide a solid carbon source for the nitrification and denitrification process that can provide a sufficient amount of carbon source without being discharged with the flowing water becomes a very important issue.

The present disclosure provides a solid carbon source, comprising: a plurality of strip units having at least one turning portion, each strip unit forming a limiting portion by the turning portion, and any of the strip units is disposed in the limiting portion At least another strip unit, wherein the plurality of strip units are integrated into a skeleton structure; and a plurality of gaps are formed between any of the strip units for gas or liquid to pass through, wherein each of the strips is formed The material of the unit is a composite material having a density system of more than 0.9 g/cm ³ .

The present disclosure provides a bioreactor comprising: a retentate space, a reaction zone located in the retentate space, a feed inlet communicating with the retentate space, and a body of a feed port communicating with the retentate space; and placing the reaction The solid carbon source disclosed in the region, wherein the reaction zone has a fluid passage formed by the plurality of gaps, and the fluid passage is in communication with the feed inlet and the feed outlet.

The present disclosure further provides a method for treating wastewater, comprising: contacting wastewater, activated sludge with a solid carbon source having the present disclosure, and passing the wastewater through the plurality of gaps to obtain treated wastewater.

1‧‧‧solid carbon source

10,10’‧‧‧ strip unit

100‧‧‧Limited area

101‧‧‧ Turning Department

102‧‧‧Extension

2‧‧‧Bioreactor

20‧‧‧ body

200‧‧‧ stranded space

21‧‧‧ Feeding entrance

22‧‧‧Feedback

P‧‧‧ fluid channel

S‧‧‧Reaction area

X‧‧‧x axis

Y‧‧‧y axis

Z‧‧‧z axis

1 is a partial schematic view showing a solid carbon source of the present disclosure; FIGS. 2A to F are views showing various aspects of a turning portion of a strip unit in the solid carbon source of the present disclosure; and FIG. 3 is a view showing the present disclosure. Photograph of solid carbon source of one embodiment; Fig. 4 is a side view showing the bioreactor of the present disclosure; Fig. 5 is a graph showing changes of COD, nitrogen nitrate content and pH value of the wastewater of Example 1 of the present disclosure. Figure 6 is a graph showing changes in volumetric load and removal rate of nitrate nitrogen in the wastewater of Example 1 of the present disclosure; and Figure 7 is a graph showing changes in COD and nitrate nitrogen content in the wastewater of Example 2 of the present disclosure; The figure shows the change of volume load and removal rate of nitrate nitrogen in the wastewater of Example 2 of the disclosure; FIG. 9 shows the change of COD and nitrate nitrogen content in the wastewater of Example 3 of the disclosure; FIG. 10 shows the disclosure. FIG. 11 is a graph showing changes in the content of COD and nitrate in the wastewater of Example 3; FIG. 12 is a graph showing the change in the content of COD and nitrate in the wastewater of Example 4 of the present disclosure; Volume load and removal of nitrate nitrogen in wastewater Fig. 13 is a graph showing changes in COD and nitrate nitrogen content in the wastewater of Example 5; and Fig. 14 is a graph showing changes in volumetric load and removal rate of nitrate nitrogen in the wastewater of Example 5 of the present disclosure. .

The embodiments of the present disclosure are described below with reference to the specific embodiments, and those skilled in the art can readily understand the advantages and functions of the present disclosure. The term "limit zone" as used in the present disclosure means the zone or range defined by the inner edge of the turning portion, or the range defined by the inner edge and the extension of the turning portion, thereby Strip elements of this range can only have a limited displacement.

In the present disclosure, "volume loading of nitrogen nitrate" refers to the total amount of nitrogen that can be treated per ton of tank per day, that is, the volumetric load of nitrogen nitrate, so the unit is kg-N/ m ³ .day.

The present disclosure may be implemented or applied by other different embodiments. The details of the present specification may also be based on different viewpoints and applications, and different modifications may be made without departing from the spirit of the disclosure. With changes.

Referring to Figures 1 to 3, in the solid carbon source 1 of the present disclosure, the method includes: a plurality of strip units 10, 10', each of the strip units 10 having at least one turning portion 101, each of the strip units 10 borrowing The turning portion 101 constitutes a limiting area 100, and at least one other strip unit 10' is disposed in the limiting area 100 of any one of the strip units 10, and the plurality of strip units 10, 10' are integrated into a skeleton structure. And a plurality of gaps formed between any of the strip units 10, 10' for gas or liquid passage, wherein each strip unit 10, 10' is formed to have a density system greater than 0.9 g/cm ³ composite materials. When the solid carbon source disclosed in the present invention is applied, the periphery of the skeleton structure is the reaction region S of the microorganism, and the fluid passage P through which the wastewater passes is formed through the gap.

In a specific embodiment, each of the strip units 10, 10' has a plurality of turning portions 101, for example, each of the strip units 10, 10' has at least one extension portion 102 for connecting the turning portion 101.

In another embodiment, the limiting area 100 is formed by the turning portion 101 and the extending portion 102.

In still another embodiment, each of the strip units extends over different coordinates of the three-dimensional space. Specifically, each strip unit is misaligned and/or wound between the strip units, and the plurality of strip units are Integrating into a skeleton structure, as shown in Figures 1 and 2, each of the turning portion 101 and the extending portion 102 of the strip unit may be located on the same or different planes, and have different x-axis (in the figure) The three-dimensional coordinates of X), y axis (Y in the figure) and z axis (Z in the figure).

For example, as shown in FIG. 2, several combinations of the turning portion 101 and the extending portion 102, as shown in the figure, the turning portion 101 and the extending portion 102 may have a combination of various arrangements, wherein, as in the second As shown in FIG. A, the limiting area 100 may be composed of a plurality of the turning portions 101, and has an extending portion 102 at an end portion of the turning portion 101. As shown in FIG. 2B, the strip unit has two extending portions 102 and three turning portions 101. Since the intermediate turning portion 101 is less curved, a wider limiting area 100 is surrounded. The other two limit zones 100 are smaller. Further, as shown in FIG. 2C, the extension portion 102 and the three consecutive turning portions 101 are respectively from right to left. In the exemplary embodiment, each of the turning portions 101 is also wound into a limiting portion 100. The three turning portions 101 generate three limit areas 100. Further, according to the foregoing description, the ends of the two turning portions 101 may be connected to each other, and the two turning portions 101 are not necessarily connected centrally by the extending portion 102.

Referring to FIG. 2D, the extension portion 102, the turning portion 101 (forming the limiting portion 100), the extending portion 102, and the turning portion 101 (forming another limiting portion 100) are sequentially arranged from right to left. As shown in FIG. 2E, the turning portion 101 (and the limiting portion 100 formed therein) and the reverse turning portion 101 (and another limiting portion 100 formed thereof) are sequentially included from right to left, and Further, the turning portion 101 (and the limiting portion 100) having the same winding direction as the previous turning portion 101 is formed. The figure shown in FIG. 2F includes an extending portion 102, two consecutive turning portions 101, an extending portion 102, a turning portion 101, an extending portion 102, three consecutive turning portions 101, and a further extending portion 102.

In the foregoing exemplary embodiment, each of the extending portion 102 and the turning portion 101 is located in a three-dimensional space of a three-dimensional space. Taking FIG. 2 as an example, the relative relationship between the two extending portions 102 that are seen as contact is actually before and after. (ie, the y-axis coordinates are not the same), therefore, the extension portion 102 is not in contact.

In other embodiments, the plurality of strip units further have at least one connecting portion, such as a connecting point (or a contact point), so that the skeleton structure formed by the plurality of strip units can be made more stable. For example, the connection between the plurality of strip units may cause at least two of the strip units to be physically joined, such as by fitting or snapping, or may be chemically bonded, such as cemented.

In still another embodiment, the solid carbon source is composed of at least two strip units, each strip unit extending over different coordinates of the three-dimensional space, each strip unit being wound in a winding manner or Around each other, or another of the wound strip units are surrounded by each other.

According to the foregoing description and the specific embodiment of the disclosed solid carbon source as shown in FIG. 1, each strip unit has a plurality of turning portions to provide more limiting regions, and the plurality of strip units are assembled Thereafter, the strength of the solid carbon source is increased to prevent the strip unit from detaching from the skeleton structure of the solid carbon source, and at the same time, the solid carbon source has a certain compressive elasticity to be more easily filled into the bioreactor.

In one embodiment, the material forming the strip unit comprises starch and a biodegradable polymer, and the weight ratio of the starch to the biodegradable polymer is from 3:7 to 7:3. When the proportion of the starch is too high, excessive carbon source overflow may occur, resulting in high COD of the outflow water. However, if the ratio of the starch is too low, the carbon source in the system is insufficient for the microorganism to utilize, and the waste water is used. The processing effect is not good.

In another embodiment, the material forming the strip unit is composed of starch and a biodegradable polymer, and the weight ratio of the starch to the biodegradable polymer is from 3:7 to 7:3.

In the foregoing embodiments, the starch may be a modified or unmodified starch, wherein the unmodified starch includes, but is not limited to, corn starch, tapioca starch or potato starch, and the modified starch includes, but not Limited to polyol modified starch, esterified starch or etherified starch, for example, the polyol is glycerol, sorbitol or polyethylene glycol (PEG).

In the foregoing embodiments, the biodegradable polymer is selected from the group consisting of polycaprolactone (PCL), polylactic acid (PLA), and terephthalic acid-adipate-butanediol copolymer (poly (butylene adipate-co-terephthalate), PBAT), polybutylene succinate (PBS) and poly(butylene succinate-co-adipate), PBSA At least one of the groups formed.

In one aspect of the preparation of the strip unit, starch, such as thermoplastic starch (TPS) and polycaprolactone (PCL), are fed into the twin-screw extruder at a temperature of 60 to 190 ° C to 30 to 30 per hour. The screw speed of 250 rpm was pushed out. Next, the extrudate is rotated in a three-dimensional, non-directional manner and/or inverted to form a solid carbon source having a plurality of strip-shaped units having a plurality of turning portions.

According to the foregoing method, in a specific embodiment, the composite material is a porous composite material, and the composite material has a porosity of 10 to 50% based on the total volume of the composite material. In one embodiment, the composite has a specific surface area of from 100 to 1000 cm ² /g.

In yet another embodiment, the composite has a density of from 0.95 to 1.2 g/cm ³ .

In one embodiment, the strip-shaped unit has an aspect ratio of 40:1 to 1000:1. In one embodiment, the strip unit has a length of 20 cm to 100 cm, and the strip unit has a diameter of 1 mm to 5 mm.

The present disclosure provides a method for treating wastewater, comprising: contacting wastewater, activated sludge with a solid carbon source having the solid carbon source disclosed herein, and flowing the wastewater through the plurality of gaps to obtain treated wastewater.

In one embodiment, the wastewater and activated sludge are contacted with the solid carbon source of the present disclosure under a volumetric loading condition of 0.4 to 1.0 kg-N/m ³ .day, and the wastewater is passed through the plurality of gaps. In addition, the volumetric load of the nitrogen may also be 0.4 to 0.8 kg-N/m ³ .day, 0.4 to 0.7 kg-N/m ³ .day, 0.6 to 0.8 kg-N/m ³ .day or 0.7 to 0.8 kg. -N/m ³ .day.

In a specific embodiment, the wastewater contains 50 mg/L to 600 mg/L of nitrogen nitrate, for example, 50 mg/L to 450 mg/L.

In one embodiment, the wastewater has a pH of from 6.5 to 8.0.

In one embodiment, the treated wastewater has a COD value of less than 100 mg/L, for example, less than 50 mg/L.

In order to make the wastewater treatment method of the present invention have a better effect, as shown in FIG. 4, the present disclosure provides a bioreactor 2 comprising: a body 20 having a retention space 200 and a reaction zone S located in the retention space 200. a feed inlet 21 communicating with the retention space 200 and a feed outlet 22 communicating with the retention space 200; and a solid carbon source 1 having the present disclosure disposed in the reaction zone S, wherein the reaction zone S has A fluid passage P formed by a plurality of gaps, and the fluid passage P is in communication with the feed inlet 21 and the feed outlet 22. For example, the fluid passage P is composed of a plurality of gaps between the plurality of strip units 10, 10' (as shown in FIG. 1) in the solid carbon source 1, and the solid carbon source 1 is not filled with the reaction region. The gap left by S is composed.

In one embodiment, the volume of the reaction zone S is 50 to 80% based on the total volume of the retention space 200. In the present embodiment, wherein the total volume of the plurality of strip units 10, 10' accounts for 20 to 60%, and the total volume of the fluid passage P is 40 to 80%, based on the total volume of the reaction area S.

According to the disclosure, the solid carbon source can be retained in the water body by forming a composite material having a density of more than 0.9 g/cm ³ , and maintaining a good carbon supply effect.

In addition, the strip unit of the solid carbon source can generate a plurality of limiting regions through the turning portion, and the limiting carbon region retains a certain proportion of the space in the solid carbon source, and transmits the misalignment between the strip units. Arranging and/or winding, so that the integrated skeleton structure maintains a gap between adjacent strip units greater than the diameter of each strip unit, and uses the plurality of gaps as a fluid passage, the fluid passage not only providing liquid flow However, it can be used as a gas exclusion channel to avoid gas accumulation, so that the nitrogen generated during the reaction process is removed, and nitrogen gas is prevented from propelling the solid carbon source to float out of the water surface, so that the solid carbon source is not easily discharged. Water loss.

 Test case:  

Elongation: Tensile strength and elongation were measured according to the standard method of ASTM D638.

Volume of reaction zone: The reactor is filled with a volume of solid carbon source. Taking Example 1 as an example, a cylindrical reactor of 377 cm ³ was filled with 95 g of a solid carbon source having a volume of 377 cm ³ × 60%, and therefore, a volume filled with a solid carbon source was 226.2 cm ³ .

Volume of fluid channel: The volume of the reaction zone minus the volume of the solid carbon source. Taking Example 1 as an example, in Example 1, the volume of the reaction zone was 226.2 cm ³ (377 cm ³ × 60%), and the total volume of the plurality of strip units in the solid carbon source was 93.1 cm ³ (95 g ÷ 1.02 g). /cm ³ ), therefore, in Example 1, the volume of the fluid passage in the reaction zone was 133.1 cm ³ .

 Preparation Example 1 Preparation of a solid carbon source (50% TPS/50% PCL)  

Feeding 750g of thermoplastic starch (TPS) and 750g of polycaprolactone (PCL) into the twin-screw extruder, so that the content of TPS and PCL is 50% by weight and 50% by weight of the total composite material, at a temperature of 90 ° C, The screw rotation speed is extruded at 120 rpm, and the extrudate is rotated in a three-dimensional direction and/or inverted to form a fiber network solid carbon source having a plurality of strip-shaped units having a plurality of turning portions, the solid carbon source having a density of 1.02 g. /cm ³ , the diameter is 2 mm, the porosity is 17.64% (about 18%) (wherein the closed cell ratio is 4.44% (about 4%), the open cell ratio is 13.81% (about 14%)), and the specific surface area is 273cm ² /g.

In the present preparation, the thermoplastic starch (TPS) is mixed with 100 phr (parts per hundred resin) of tapioca starch, 40 phr of water and 20 phr of glycerin at 60 ° C, and heated to 70 by a single screw strong granulator. The modified thermoplastic starch particles were obtained at ° C for 8 minutes.

In Preparation Example 1, the solid carbon source had a tensile strength of 36 kgf/cm ² and an elongation of 4.54%.

 Preparation Example 2 Preparation of a solid carbon source (60% TPS/40% PCL)  

900g of thermoplastic starch (TPS) and 600g of polycaprolactone (PCL) are fed into the twin-screw extruder, so that the TPS and PCL content is 60% by weight and 40% by weight of the total composite material, at a temperature of 90 ° C, The screw rotation speed is extruded at 120 rpm, and the extrudate is rotated in a three-dimensional direction and/or inverted to form a fiber network solid carbon source having a plurality of strip-shaped units having a plurality of turning portions, the solid carbon source having a density of 1.09 g. /cm ³ , the diameter is 2 mm, the porosity is 25.63% (about 26%) (wherein the closed cell ratio is 2.38% (about 2%), the open cell ratio is 23.82% (about 24%)), and the specific surface area is 356 cm ² /g.

In the present preparation, the thermoplastic starch (TPS) is mixed with 100 phr (parts per hundred resin) of tapioca starch, 40 phr of water and 20 phr of glycerin at 60 ° C, and heated to 70 by a single screw strong granulator. The modified thermoplastic starch particles were obtained at ° C for 8 minutes.

In Preparation Example 2, the solid carbon source had a tensile strength of 35 kgf/cm ² and an elongation of 3.95%.

 Preparation Example 3 Preparation of a solid carbon source (70% TPS/30% PCL)  

Feeding 1050g of thermoplastic starch (TPS) and 450g of polycaprolactone (PCL) into the twin-screw extruder, so that the content of TPS and PCL is 70% by weight and 30% by weight of the total composite material at a temperature of 90 ° C. The screw rotation speed is extruded at 120 rpm, and the extrudate is rotated in a three-dimensional non-directional manner and/or inverted to form a fiber network solid carbon source having a plurality of strip-shaped units having a plurality of turning portions, the solid carbon source having a density of 1.10 g. /cm ³ , a diameter of 2 mm, a porosity of 9.64% (about 10%) (wherein a closed cell ratio of 0.56% (about 1%), an open cell ratio of 9.13% (about 9%)), and a specific surface area of 951 cm ² /g.

In the present preparation, the thermoplastic starch (TPS) is mixed with 100 phr (parts per hundred resin) of tapioca starch, 40 phr of water and 20 phr of glycerin at 60 ° C, and heated to 70 by a single screw strong granulator. The modified thermoplastic starch particles were obtained at ° C for 8 minutes.

In Preparation Example 3, the solid carbon source had a tensile strength of 31 kgf/cm ² and an elongation of 3.19%.

 Preparation Example 4 Preparation of a solid carbon source (50% TPS/50% PBAT)  

750g of thermoplastic starch (TPS) and 750g of terephthalic acid-adipate-butanediol copolymer (PBAT) are fed into the twin-screw extruder, so that the content of TPS and PBAT accounts for 50% by weight of the total composite material. With 50wt%, at a temperature of 140 ° C, at a screw speed of 150 pm per hour, in the water, the extrudate is rotated in a three-dimensional non-directional direction and / or inverted to form a fiber network solid carbon source with a plurality of strip-shaped units of a plurality of turning parts The solid carbon source has a density of 1.05 g/cm ³ and a diameter of 2 mm.

In the present preparation, the thermoplastic starch (TPS) is a mixture of 100 phr (parts per hundred resin (or rubber) of tapioca starch, 35 phr of water and 15 phr of glycerin at 80 ° C, and is made of a single screw. The machine was heated to 90 ° C for 10 minutes to obtain modified thermoplastic starch particles.

In Preparation Example 4, the solid carbon source had a tensile strength of 66 kgf/cm ² and an elongation of 51%.

 Preparation Example 5 Preparation of a solid carbon source (50% TPS/50% PLA)  

750g of thermoplastic starch (TPS) and 750g of polylactic acid (PLA) are fed into the twin-screw extruder, so that the TPS and PLA content is 50% by weight and 50% by weight of the total composite material, at a temperature of 170 ° C, at a screw speed Extrusion at 250 rpm, the extrudate is rotated in a three-dimensional direction and/or inverted to form a fibrous network-like solid carbon source having a plurality of strip-shaped units having a plurality of turning portions, the density of the solid carbon source being 0.99 g/cm. ³ , the diameter is 2mm.

In the present embodiment, the thermoplastic starch (TPS) is mixed with 100 phr (parts per hundred resin (or rubber) of tapioca starch, 50 phr of water and 25 phr of glycerin at 95 ° C, and is made of a single screw. The machine was heated to 100 ° C and maintained for 30 minutes to obtain modified thermoplastic starch particles.

In Preparation Example 5, the solid carbon source had a tensile strength of 40 kgf/cm ² and an elongation of 0.99%.

In the above preparation example, the step of mixing the tapioca starch, water and glycerin may also be stirred at a temperature of 30 to 95 ° C for 5 to 30 minutes with a kneader, and at a temperature of 70 to 130 ° C for 3 to 20 minutes. Granulated modified thermoplastic starch particles are prepared.

In this embodiment, the extrudate is in water and is non-directionally rotated and/or inverted in three dimensions (ie, x-axis, y-axis, and z-axis), for example, when the extrudate is in the y-axis direction (ie, perpendicular to When the x-axis and the z-axis form a discharge, the direction is the axial movement toward the x-axis and then the z-axis is reversed, and then moved in the opposite direction of the discharge direction to be folded in the y-axis direction. Further, a fiber-like solid carbon source of a plurality of strip-shaped units having a plurality of turning portions is formed from the z-axis direction as shown in FIG.

 Example 1 Treatment of Wastewater by the Treatment Method of the Bioreactor of the Present Invention  

A cylindrical reactor having a volume of 377 ml was filled with 95 g of the solid carbon source prepared in Preparation Example 1 (TPS/PCL was 50 wt%/50 wt%), and filled up from the bottom of the cylindrical reactor to the height of the entire cylindrical reactor. 60% (about 226.2 ml), the reaction area accounts for 60% of the total cylindrical reactor, and its volume load is 0.4 to 0.8 kg N/m ³ -d, based on the total volume of the reaction zone (about 226.2 ml). The total volume of the plurality of strip units accounts for 41.2% of the reaction zone, the fluid channel accounts for about 58.8%, and the 300 ml of denitrified sludge (activated sludge) is planted at a concentration of 2.94 g/L. , the hydraulic retention time (HRT, that is, the time when the wastewater is in contact with the solid carbon source), as shown in Figure 5, is continuously operated, and the COD value, the nitrogen nitrate content and the pH value are measured every 3 days, and The results are recorded in Figures 5 and 6.

In Figure 5, the solid squares indicate the nitrate nitrogen content of the influent, the open squares indicate the nitrogen nitrate content of the influent, the solid circles indicate the COD values of the influent, the open circles indicate the COD values of the influent, and the triangles are the pH values. Figure 6 is a graph showing the volumetric load and removal rate of nitrate nitrogen in the wastewater of Example 1 in the present disclosure. In the figure, the solid square indicates the removal rate of nitrogen nitrate, and the hollow square indicates the nitrogen nitrate. Load (volume load).

According to the experimental results in Fig. 5, it was found that the solid carbon source of the present invention was treated for 147 days (nearly 150 days), and the influent nitrogen nitrate concentration was gradually increased from 200 mg/L to 350 mg/L, and the COD value in the discharged water was still low. According to the discharge standard of 100mg/L, the solid carbon source of the present disclosure does not disintegrate under the condition of continuous treatment for nearly 150 days, and does not release excessive carbon, and the solid carbon source having the present disclosure is used. After treatment with the wastewater treatment method, the content of nitrate nitrogen decreased significantly after the 24th day, and decreased significantly after 50 days. At the 60th day of treatment, the nitrate nitrogen concentration of the outflow could be lower than 50mg/L. The removal rate is as high as 80%.

Moreover, from the 100th to 150th day of the fifth figure, the nitriding reaction of nitrogen nitrate is the most active time (about the 125th day), and the influent nitrogen nitrate content is more than 350mg/L, and the nitrate nitrogen is discharged. The content is less than 50 mg/L, and the COD amount of the inflow at the time point is less than 50 mg/L. At this time, the carbon source of the denitrifying bacteria in the activated sludge is the solid carbon source disclosed herein, and the carbon amount of the solid carbon source is released. The carbon source required for maintaining the denitration reaction of denitrifying bacteria, and the amount of COD released therefrom is less than 50 mg/L. It is known that most of the carbon released by the solid carbon source is utilized by microorganisms. The amount of carbon in the solid carbon source disclosed in the present disclosure does not cause waste of carbon excess.

The volume load (volume load) and the removal rate change diagram of the nitrogen nitrate in the wastewater of Example 1 of the present disclosure shown in Fig. 6 show that the volumetric load of nitrogen nitrate is 0.8 to 1 at the initial stage of the reaction (about 1 to 27 days). The removal rate was 10 to 20%, but after 60 days, the removal rate was increased to 80% or more, and the removal rate was maintained at 95% or more after 80 days of treatment.

In addition, the data of Example 1 (see Figures 5 and 6 for details) was carried out for the removal rate and volume load test of nitrate nitrogen at different concentrations, and the results are shown in Table 1 below.

Table 1

As shown in Table 1, regardless of the influent nitrogen nitrate concentration of 200mg / L, 250mg / L, 300mg / L or 350mg / L, can have a removal rate of 80% or more, more preferably, the removal rate can be higher than 90%, even 97% removal rate.

In the foregoing embodiment, after maintaining the influent nitrogen nitrate concentration of 200 mg/L for about 28 days, the influent nitrogen nitrate concentration is increased to 250 mg/L for 24 days, in other words, the average removal rate is The average removal rate for that number of days.

 Example 2 Treatment of Wastewater by the Treatment Method of the Bioreactor of the Present Invention  

A cylindrical reactor having a volume of 377 ml was filled with 65.3 g of the solid carbon source prepared in Preparation Example 2 (TPS/PCL was 60 wt%/40 wt%), and filled up from the bottom of the cylindrical reactor to the height of the entire cylindrical reactor. 60% of the reaction zone accounts for 60% of the total cylindrical reactor, and its volumetric load is 0.7 to 0.8 kg N/m ³ -d. The filling ratio of the solid carbon source accounts for 26.5% of the reaction zone, and the ratio of the fluid channel Approximately 73.5%, planted 300ml of denitrified sludge (activated sludge), its concentration is 2.94g / L, continuous operation, sample the measured COD value and nitrate nitrogen content every 10 days, and record the results Figures 7 and 8.

In Figure 7, the solid squares indicate the nitrate nitrogen content of the influent, the open squares indicate the nitrate nitrogen content of the influent, the solid circles indicate the COD values of the influent, and the open circles indicate the COD values of the influent. Figure 8 is a graph showing the volumetric load (volume load) and removal rate of nitrate nitrogen in the wastewater of Example 2, in which the solid square indicates the removal rate of nitrogen nitrate, and the open square indicates the loading of nitrogen nitrate (volume). load).

According to the experimental results of Figures 7 and 8, it can be seen that the wastewater treated by the bioreactor of the present invention treats the influent nitrogen nitrate concentration at 500 to 600 mg/L, and after 10 days of domestication, the removal rate of nitrate nitrogen can reach Above 90%, the average COD of the outflow is less than 100 mg/L, and the average nitrate concentration is less than 50 mg/L.

 Example 3 Treatment of wastewater by the treatment method of the bioreactor disclosed herein  

The cylindrical reactor having a volume of 377 ml was filled with 80.3 g of the solid carbon source prepared in Preparation Example 3 (TPS/PCL was 70 wt%/30 wt%), and filled up from the bottom of the cylindrical reactor to the height of the entire cylindrical reactor. 60% of the reaction area accounts for 60% of the total cylindrical reactor, and its volume load is 0.4 to 0.7 kgN/m ³ -d. The filling ratio of the solid carbon source accounts for 33.3% of the total reaction area. The ratio is about 66.7%, planting 300ml of denitrified sludge (activated sludge), its concentration is 2.94g / L, continuous operation, sample the measured COD value and nitrate nitrogen content every 3 days, and record the results In Figures 9 and 10.

In Fig. 9, the solid square indicates the nitrate nitrogen content of the inflow, the open square indicates the nitrogen nitrate content of the inflow, the solid circle indicates the COD value of the inflow, and the open circle indicates the COD value of the discharge. Figure 10 is a graph showing the volumetric load (volume load) and removal rate of nitrate nitrogen in the wastewater of Example 3, in which the solid square indicates the removal rate of nitrogen nitrate, and the hollow square indicates the loading of nitrogen nitrate (volume). load).

According to the experimental results of Figures 9 and 10, it can be seen that the wastewater treated by the bioreactor of the present invention treats the influent nitrogen nitrate concentration from 400 mg/L to 500 mg/L, and the volume load is 0.5 kgN/m ³ - d gradually increased to 0.7kgN / m ³ -d, while the removal rate of nitrate nitrogen can still be maintained above 90%, the average COD of the outflow water is less than 100mg / L, and the average nitrate nitrogen concentration is less than 50mg / L.

 Example 4 Treatment of Wastewater by the Treatment Method of the Bioreactor of the Present Invention  

A cylindrical reactor having a volume of 377 ml was filled with 60.8 g of the solid carbon source prepared in Preparation Example 4 (TPS/PBAT was 50 wt%/50 wt%), and filled up from the bottom of the cylindrical reactor to the height of the entire cylindrical reactor. 60% (about 226.2 ml), the reaction area accounts for 60% of the total cylindrical reactor, and its volume load is 0.6 to 0.8 kgN/m ³ -d, and the total volume of the reaction zone (about 226.2 ml) The total volume of the plurality of strip units accounts for 25.6% of the reaction zone, the fluid channel accounts for about 74.4%, and the 350 ml of denitrified sludge (activated sludge) is planted at a concentration of 2.94 g/L. Continuous operation, sample the measured COD value, nitrate nitrogen content and pH value every 5 days, and record the results in Figures 11 and 12.

In Fig. 11, the solid square indicates the nitrate nitrogen content of the inflow, the open square indicates the nitrate nitrogen content of the inflow, the solid circle indicates the COD value of the inflow, and the open circle indicates the COD value of the discharge. Figure 12 is a graph showing the volumetric load (volume load) and removal rate of nitrate nitrogen in the wastewater of Example 4, in which the solid square indicates the removal rate of nitrogen nitrate, and the open square indicates the loading of nitrogen nitrate (volume). load).

According to the experimental results of Figures 11 and 12, it can be seen that the wastewater treated by the bioreactor of the present invention treats the influent nitrogen nitrate concentration at 250 mg/L and the nitrate nitrogen removal rate at 65 to 95%.

 Example 5 Treatment of Wastewater by the Treatment Method of the Bioreactor of the Present Invention  

A cylindrical reactor having a volume of 377 ml was filled with 36.5 g of the solid carbon source prepared in Preparation Example 5 (TPS/PLA 50 wt%/50 wt%), and filled up from the bottom of the cylindrical reactor to the height of the entire cylindrical reactor. 60% (about 226.2 ml), the reaction area accounts for 60% of the total cylindrical reactor, and its volume load is 0.6 kgN/m ³ -d, based on the total volume of the reaction zone (about 226.2 ml). The total volume of the plurality of strip units accounts for 15.4% of the reaction zone, the fluid channel accounts for about 84.6%, and the 350 ml of denitrified sludge (activated sludge) is planted at a concentration of 2.94 g/L, and is continuously operated. The COD value, nitrate nitrogen content and pH value of the water were sampled every 5 days, and the results were recorded in Figures 13 and 14.

In Fig. 13, the solid square indicates the nitrogen nitrate content of the inflow, the open square indicates the nitrate nitrogen content of the inflow, the solid circle indicates the COD value of the inflow, and the open circle indicates the COD value of the discharge. Figure 14 is a graph showing the volumetric load (volume load) and removal rate of nitrate nitrogen in the wastewater of Example 5, in which the solid square indicates the removal rate of nitrogen nitrate, and the open square indicates the loading of nitrogen nitrate (volume). load).

According to the experimental results of Figures 13 and 14, it can be seen that the wastewater treated by the bioreactor of the present invention treats the nitrogen nitrate concentration of the inflow to be maintained at 250 mg/L, and the nitrogen nitrate removal rate can reach over 90%. Insufficient, the removal rate dropped to 20 to 60%.

It can be seen from the embodiments of the present disclosure that the solid carbon source of the present invention not only can release the effect for a long time, but also has the characteristics of high specific surface area, which can make the microorganisms adhere to the solid carbon source in a large amount, and can fully utilize the organic carbon source and the carbon source lost through the water flow. Limited, the outflow does not require further carbon removal.

In summary, the solid carbon source of the present disclosure has a large specific surface area and can be attached to microorganisms, so the treatment load is high, and the gas is effectively discharged through the fluid passage to avoid gas accumulation, so as to avoid when the denitration reaction is strong. The gas production is too fast and the skeleton structure of the solid carbon source is decomposed or lost. It can be applied to wastewater with a nitrate nitrogen concentration higher than 200 mg/L, and can be applied to industrial wastewater.

The above embodiments are merely illustrative of the principles of the disclosure and its functions, and are not intended to limit the disclosure. Any person skilled in the art can modify and change the above embodiments without departing from the spirit and scope of the disclosure. Therefore, the scope of protection of the present disclosure should be as set forth in the scope of the patent application described later.

Claims (19)

A solid carbon source, comprising: a plurality of strip units, each strip unit having at least one turning portion, wherein the turning portion constitutes a limiting portion, and at least one of the limiting portions of the strip unit is disposed at least a strip unit, wherein the plurality of strip units are integrated into a skeleton structure; and a plurality of gaps are formed between any two strip units for gas or liquid to pass through, wherein each strip unit is formed The material is a composite material having a density system greater than 0.9 g/cm ³ .  The solid carbon source of claim 1, wherein each of the strip units has a plurality of turning portions.    The solid carbon source according to claim 2, wherein each of the strip units has at least one extension portion for connecting the turning portion, and the limiting portion is formed by the turning portion and the extending portion.    The solid carbon source according to claim 1, wherein each of the strip units is misaligned and/or entangled, and the plurality of strip units are integrated into a skeleton structure.   The solid carbon source of claim 1, wherein the composite has a density of from 0.95 to 1.2 g/cm ³ . The solid carbon source according to claim 1, wherein the composite material has a specific surface area of 100 to 1000 cm ² /g.  The solid carbon source according to claim 1, wherein the composite material is a porous composite material, and the composite material has a porosity of 10 to 50% based on the total volume of the composite material.    The solid carbon source according to claim 1, wherein the strip unit has an aspect ratio of 40:1 to 1000:1.    The solid carbon source according to claim 1, wherein the material forming the strip unit comprises starch and a biodegradable polymer, and the weight ratio of the starch to the biodegradable polymer is 3:7 to 7:3.    The solid carbon source according to claim 9, wherein the biodegradable polymer is selected from the group consisting of polycaprolactone, polylactic acid, terephthalic acid-adipate-butanediol copolymer, and polybutylene. At least one of the group consisting of butylene glycol diester and polybutylene succinate adipic acid copolymer.    The solid carbon source according to claim 1, wherein the plurality of strip units further have at least one connecting portion.    A bioreactor comprising: a body having a retention space, a reaction zone located in the retention space, a feed inlet in communication with the retention space, and a feed outlet in communication with the retention space; and The solid carbon source is disposed in the reaction zone, wherein the reaction zone has a fluid passage formed by the plurality of gaps, and the fluid passage is in communication with the feed inlet and the feed outlet.    The bioreactor according to claim 12, wherein the reaction zone has a volume of 50 to 80% based on the total volume of the retained space.    The bioreactor of claim 13, wherein the total volume of the plurality of strip units is from 20 to 60% based on the total volume of the reaction zone.    A method for treating wastewater comprises contacting wastewater and activated sludge with a solid carbon source as described in claim 1 of the patent application, passing the wastewater through the plurality of gaps to obtain treated wastewater.    The method for treating wastewater according to claim 15, wherein the wastewater contains 50 mg/L to 600 mg/L of nitrogen nitrate.    The method for treating wastewater according to claim 15, wherein the wastewater has a pH of 6.5 to 8.0.   The method for treating wastewater according to claim 15 is to make the wastewater and activated sludge have the first item of the patent application range under a volume load condition of 0.4 to 1.0 kg-N/m ³ .day. The solid carbon source is contacted to pass the wastewater through the plurality of gaps.  The method for treating wastewater according to claim 15, wherein the treated wastewater has a COD value of less than 100 mg/L.