TWI520913B - Method of biological treating ammonia-containing wastewater - Google Patents

Description

Method for biologically treating ammonia nitrogen wastewater

The invention relates to a method for treating wastewater, in particular to a method for treating wastewater containing ammonia-nitrogen wastewater into nitrite by domesticating sludge of coking wastewater.

With the continuous development of modern industry and the widespread application of chemical fertilizers and pesticides, the content of nitrogenous substances in wastewater increases, and the impact on the environment is enormous. Nitrogen-containing substances in water generally include organic nitrogen, ammonia nitrogen, nitrite and nitrate, but ammonia nitrogen and nitrate are the main components. Ammonia nitrogen refers to a compound which exists in the form of undissociated ammonia (NH ₃ ) or dissociated ammonium (NH ₄ ⁺ ), and is an indicator of contamination of a water body.

Because the ammonia nitrogen in the water is biologically reacted to produce nitrate, it will cause the water body to be eutrophic, so that the algae in the water will overproduce, the water will have astringency, or even produce toxic blue-green algae, and the ammonia will not be dissociated from the aquatic organisms. The toxicity is high, causing the water quality to deteriorate and the lake to degenerate. Secondly, ammonia nitrogen in water is also an oxygen-consuming pollutant. When ammonia nitrogen is decomposed by biooxidation, it will consume dissolved oxygen in the water. When it is serious, it will make the water body black and smelly. In addition, ammonia nitrogen causes odor in water, causes water body to be eutrophic, and also has a negative effect on drinking water, seriously damaging water ecology. surroundings. Therefore, how to control the ammonia nitrogen content in wastewater has become one of the important topics in wastewater treatment, and relevant units at home and abroad have formulated relevant specifications such as ammonia nitrogen and nitrate concentration to control the discharge of wastewater and ensure the quality of drinking water sources.

At present, the treatment technology of ammonia nitrogen can be roughly divided into biological treatment methods and physical chemical treatment methods depending on whether it involves biological reactions. Conventional physicochemical treatment methods may be, for example, a fluorination method, a selective ion exchange method, an air stripping method, a stripping method, a chemical precipitation method, or the like. However, most physicochemical treatment methods are costly and have a certain degree of interference and side effects, so biological treatment methods are still relatively economical and effective.

The conventional biological treatment method is to complete the nitrification process (ie, oxidize ammonia nitrogen to nitrite and nitrate) by self-operating bacteria in an aerobic environment, and then nitrate (NO ₃ ^- by denitrifying bacteria in an anaerobic environment). Conversion to nitrite (NO ₂ ^- ) and conversion of nitrite to nitrogen (N ₂ ).

In order to increase the speed of anaerobic biological treatment, the industry has developed a number of improved energy-saving denitrification steps, such as short-range nitrification and denitration steps, anaerobic ammonium oxidation steps, and the like. The short-range nitrification and denitration step described above is a step of controlling the oxidation of ammonia nitrogen to nitrite in a micro-oxygen environment without generating nitrate. Thereafter, the nitrite is directly converted to nitrogen in the anaerobic ammonium oxidation step. As for the anaerobic ammonium oxidation step, part of the ammonia nitrogen is oxidized to nitrite, and then the ammonia nitrogen and the nitrite are reacted into nitrogen under an anaerobic environment.

In short, the key to the short-range nitrification denitration step and the anaerobic ammonium oxidation step described above is how to control the stable nitrite and inhibit the microbial oxidation of the nitrite to nitrate.

The conventional method controls the dissolved oxygen and the operation in the biological treatment device Treatment conditions such as temperature, sludge residence time, substrate concentration, aeration mode, and addition of chemical inhibitors can inhibit the oxidation of nitrite to nitrate by microorganisms. However, when the above method is applied to actual operation, the treated water is often used. It is difficult to obtain a stable concentration of nitrite.

In view of the above, there is a need to provide a method for biologically treating ammonia-containing nitrogen wastewater to overcome the problem of the inability to stably control the concentration of nitrite in treated water in a conventional manner.

Therefore, one aspect of the present invention provides a method for biologically treating ammonia-containing nitrogen wastewater, which can effectively convert ammonia nitrogen containing ammonia-nitrogen wastewater into nitrite by using a sludge domesticated by coking wastewater in an aerobic environment. Significantly reduce the production of nitrate.

According to the above aspect of the invention, a method of biologically treating wastewater containing ammonia nitrogen is proposed. In one embodiment, the method comprises carrying out a domesticating step of reacting the biologically activated sludge with the coking wastewater in an aerobic environment to obtain domesticated sludge, wherein the ammonia oxidizing bacteria group of the domesticated sludge is superior to the nitrous acid oxidizing bacteria group The coking wastewater includes a total phenol content of 100 mg/L (mg/L) to 1000 mg/L, an ammonia nitrogen content of more than 0 mg/L to 600 mg/L, and a chemical oxygen demand of 1000 mg/L to 5000 mg/L. ; COD), the sludge residence time of the aforementioned biologically activated sludge may be, for example, at least 20 days, and the aforementioned domestication step is performed for at least 180 days.

Next, the domesticated sludge is introduced into the treatment device to form a biological treatment device, wherein the concentration of suspended solids in the mixed sludge of the domesticated sludge (mixed liquid suspended solid; MLSS) may be, for example, 5000 mg/L.

Then, performing a first biological treatment step, introducing ammonia-containing wastewater into the biological treatment device to react, and oxidizing ammonia nitrogen containing ammonia-nitrogen wastewater to nitrite to obtain intermediate treated water, wherein the ammonia nitrogen concentration of the ammonia-containing wastewater may be, for example, More than 0mg/L to 400mg/L but no nitrite.

In the above embodiment, the processing conditions of the first biological treatment step may further include: the ratio of the ammonia-containing wastewater to the domesticated sludge may be, for example, 0 g NH ₃ -N/g MLSS to 0.2 g NH ₃ -N/g MLSS The pH value of the ammonia-containing wastewater in the biological treatment device may be, for example, pH 6.0 to 8.0, and the alkalinity of the ammonia-containing wastewater in the biological treatment device may be, for example, equivalent to 50 mg/L to 650 mg/L of calcium carbonate, and the first The operating temperature of the biological treatment step can be, for example, greater than 20 ° C to 40 ° C. The intermediate treated water thus obtained has a nitrite content of more than 0 mg/L to 400 mg/L, but does not contain ammonia nitrogen and has a nitrate content lower than one tenth of the nitrite content.

According to an embodiment of the present invention, the strain of the domesticated sludge may include, but is not limited to, the genus Oligotropha sp. of the α- Proteobacteria and the genus Sandarcinobacter. Sp. ), β- Proteobacteria sp. , Alicycliphilus sp. , Thiobacillus sp. , Nitrosomonas sp. , plexus Comamonas sp. , Ottowia sp. and Pusillimonas sp. , Firmicutes Eubacterium sp. And any combination of the above.

According to an embodiment of the present invention, in the domesticating step, the sludge retention time of the biologically active sludge is from 20 days to 60 days, and the above domesticating step is performed for at least 180 days.

According to an embodiment of the invention, the processing device can be, for example, an aeration tank or a fluidized bed. In one example, the domesticated sludge described above can be suspended in an aeration tank. In other examples, the domesticated sludge described above can be further loaded into a plurality of biological carriers, and the biological carrier can be cultured in an aeration tank or a fluidized bed.

According to an embodiment of the present invention, the alkalinity of the ammonia-containing nitrogen-containing wastewater described above may be provided by an alkali agent, and the alkali agent may be, for example, sodium hydrogencarbonate or sodium carbonate.

According to an embodiment of the invention, the first biological treatment step further comprises introducing an oxygen-containing gas into the ammonia-containing wastewater to make the dissolved oxygen content of the ammonia-containing wastewater to be, for example, 0.5 mg/L to 6.0 mg/L.

According to an embodiment of the invention, in the first biological treatment step, the operating temperature of the first biological treatment step may be, for example, 30 ° C to 35 ° C.

According to an embodiment of the present invention, after the first biological treatment step, the method further comprises: performing a second biological treatment step, performing the short-cut nitrification denitration step and/or the anaerobic ammonium oxidation step to The nitrite of the intermediate treated water is converted to nitrogen.

The method for biologically treating ammonia-containing nitrogen wastewater according to the present invention can effectively convert ammonia nitrogen containing ammonia-nitrogen wastewater into nitrite in an aerobic environment by utilizing sludge domesticated by coking wastewater to substantially reduce nitrate production. borrow By controlling the alkalinity of the ammonia-containing wastewater, the obtained intermediate treatment water nitrite can be adjusted to a desired concentration to quickly carry out the conventional short-cut nitrification denitration step and/or the anaerobic ammonium oxidation step, thereby effectively reducing the habit Know the energy consumption of the nitrification denitration program.

100‧‧‧ biological treatment device

101‧‧‧Processing tank

103‧‧‧ bubbles

Above 104‧‧‧

105‧‧‧Inflow pipe

107‧‧‧ gas pipeline

108‧‧‧Support

109‧‧‧pipe

111/113‧‧‧ probe

115/117‧‧‧ lines

121/122/123/611‧‧‧ arrows

201/203/205/209/501/503/601/603/605/607‧‧‧ Curve

The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Sectional view.

[Fig. 2] is a graph showing the number of bacteria of the main flora during the domestication of the domesticated sludge map according to an embodiment of the present invention.

[Fig. 3] is a bar graph showing changes in the content of nitrite and nitrate before and after treatment with ammonia-containing wastewater in the biological treatment step of Example 1 or Comparative Example 1.

[Fig. 4] is a bar graph showing changes in the content of nitrite and nitrate before and after treatment with ammonia-containing wastewater in the biological treatment step of Example 1 or Comparative Example 2 of the present invention.

[Fig. 5] is a standard curve showing the change of the content of nitrite and nitrate before and after the biological treatment step of the ammoniacal wastewater containing the alkalinity of Example 2.

[Fig. 6] is a graph showing the nitrite content, the nitrate content, the ammonia content, and the pH value of the alkalinity added at different times according to the biological treatment step of Example 3 of the present invention.

As described above, the present invention provides a method for biologically treating ammonia-containing wastewater, which can effectively convert ammonia nitrogen containing ammonia-nitrogen wastewater into nitrite in an aerobic environment by utilizing sludge domesticated by coking wastewater to substantially reduce nitrate. produce.

The term "ammonia-nitrogen-containing wastewater" as used herein means wastewater containing NH ₃ or NH ₄ ⁺ ammonia nitrogen.

The term "domestic sludge" as used herein refers to a bioactive sludge that reacts with coking wastewater in an aerobic environment for a domestication step, wherein the sludge retention time of the biologically activated sludge is at least 20 days, and the domestication step For example, at least 180 days to obtain domesticated sludge. In one embodiment, the biologically activated sludge may be derived from aerobic activated sludge of coke field wastewater, and the strain of the domesticated sludge may include, but is not limited to, an alpha- proteobacteria (α- Proteobacteria ) genus (Oligotropha sp.) and Mount Dare Sinofsky genus (Sandarcinobacter sp.), β- Proteobacteria (β- Proteobacteria sp.) of addicted alicyclic genus (Alicycliphilus sp.), Thiobacillus (Thiobacillus sp . ) , Nitrosomonas sp. , Comamonas sp. , Ottowia sp. and Pusillimonas sp. Firmicutes (preferably of the genus Bacillus Firmicutes (Eubacterium sp.), and any combination of the above.

It is explained here that the domesticated sludge of the present invention is practically free of nitrous acid oxidizing bacteria, or the amount of bacteria containing nitrous acid oxidizing bacteria is less than the detectable amount, or the nitrous acid oxidizing bacteria contained therein. The amount of bacteria is lower than the total amount of domesticated sludge 1% of the amount of bacteria. Since the domesticated sludge of the present invention does not contain the nitrous acid oxidizing bacteria or the amount of the bacteria is insufficient to cause the influence, the nitrite content can be effectively accumulated and the nitrate can be inhibited by treating the ammonia-containing wastewater with the domesticated sludge described above. The production.

The invention utilizes coking wastewater to domesticate biologically active sludge. In one embodiment, the coking wastewater comprises a total phenolic content of from 100 mg/L to 1000 mg/L, an ammonia nitrogen content of from greater than 0 mg/L to 600 mg/L, and a chemical aerobic content of from 1000 mg/L to 5000 mg/L. (chemical oxygen demand; COD).

In other embodiments, the domesticating step may further react the biologically activated sludge with the coking wastewater, for example, the sludge residence time may be, for example, 20 days to 60 days, and the average hydraulic retention time of the coking wastewater may be, for example, 1 day to 2 days. day.

It is explained here that if the bioactive sludge is domesticated using waste water other than the above-mentioned coking wastewater, the subsequent treatment of the domesticated sludge containing the ammonia-nitrogen wastewater cannot simultaneously accumulate the nitrite content and inhibit the production of the nitrate.

The aforementioned domesticated sludge can be introduced into the treatment device to form a biological treatment device to facilitate subsequent treatment of the ammonia-containing wastewater. The treatment device of the present invention is not limited and may be, for example, a conventional aeration tank or a fluidized bed. The aforementioned fluidized bed may be, for example, an aerobic upflow fluidized bed. In one example, when the treatment device is an aeration tank or a fluidized bed, the domesticated sludge can be suspended or placed in a support 108 to increase the concentration of the domesticated sludge, wherein the support 108 can be, for example, a biological carrier. Or biological support (such as foam, plastic, non-woven fabric, etc.), can be filled or retained micro-containing in domesticated sludge biological.

In the above embodiments, a biological treatment device suitable for use in the present invention may be, for example, a partial cross-sectional view of a biological treatment device according to an embodiment of the present invention. In FIG. 1, the biological treatment device 100 may include a treatment tank 101, such as an aeration tank or a fluidized bed. The bottom of the treatment tank 101 may be provided with an inflow water line 105, and the upper portion 104 of the treatment tank 101 may be provided with a plurality of Pipes, such as gas line 107 and line 109.

In the above embodiment, the ammonia-containing wastewater may be introduced into the treatment tank 101 through the inflow water line 105 in the direction indicated by the arrow 121 for the subsequent first biological treatment step, wherein the inflow water line 105 is more selectively set. Pump or valve (not shown) to regulate the flow of influent water.

In the above embodiment, the oxygen-containing gas may be introduced into the bottom of the treatment tank 101 through the gas line 107 in the direction indicated by the arrow 123 to release the oxygen-containing gas bubble 103, which is required for the first biological treatment step. The oxygen environment, wherein the gas line 107 is further selectively provided with a valve (not shown) to regulate the flow rate of the oxygen-containing gas.

In the above embodiment, the outflow water may be led out of the treatment tank 101 from the treatment tank 101 via the line 109 in the direction indicated by the arrow 122.

In addition, in the above embodiment, the upper portion 104 of the processing tank 101 may further be provided with a plurality of probes 111, probes 113 and the like to measure the pH value, dissolved oxygen, etc. in the processing tank 101, and the relevant measured values are passed through Line 115, line 117, etc. are transmitted to the control unit (not shown).

In an embodiment, the processing tank 101 of the biological treatment device 100 A first biological treatment step can be performed, and the first biological treatment step can be performed using the following processing conditions. The mixed liquid suspended solid (MLSS) of the aforementioned domesticated sludge in the biological treatment device may be, for example, 1000 mg/L to 7000 mg/L. If the MLSS of the domesticated sludge in the biological treatment device is less than 1000 mg/L, the treatment time is increased and the energy saving effect cannot be achieved. If the MLSS of the domesticated sludge in the biological treatment device exceeds 7000 mg/L, the outflow water is not easily subjected to solid-liquid separation.

In one embodiment, the processing conditions of the first biological treatment step further comprise: the pH value of the ammonia-containing wastewater in the biological treatment device is pH 6.0 to 8.0, and the alkalinity of the ammonia-containing wastewater in the biological treatment device can be, for example, equivalent From 50 mg/L to 650 mg/L of calcium carbonate. In an exemplary embodiment, the alkalinity of the ammonia-containing nitrogen-containing wastewater may be provided by an alkaline agent, wherein a suitable alkaline agent may be, for example, sodium hydrogencarbonate or sodium carbonate.

After the biological treatment device is prepared, the first biological treatment step can be followed. In one embodiment, the ammonia-containing wastewater is introduced into the biological treatment device for at least 30 hours, and the ammonia nitrogen containing the ammonia-nitrogen wastewater is oxidized to nitrite by the microorganisms that tamed the sludge to obtain intermediate treated water. In an example, the ammonia nitrogen concentration of the ammonia-containing wastewater may be, for example, greater than 0 mg/L to 400 mg/L but no nitrite.

When the first biological treatment step is performed, the following treatment conditions can be used: the ratio of the ammonia-nitrogen-containing wastewater to the domesticated sludge can be, for example, 0 g NH ₃ -N/g MLSS to 0.2 g NH ₃ -N/g. MLSS, the pH value of the ammonia-containing wastewater in the biological treatment device may be, for example, pH 6.0 to 8.0, and the alkalinity of the ammonia-containing wastewater in the biological treatment device may be, for example, equivalent to 50 mg/L to 650 mg/L of calcium carbonate, and the The operating temperature of a biological treatment step can be, for example, greater than 20 ° C to 40 ° C. In other examples, the operating temperature of the first biological treatment step is preferably from 30 ° C to 35 ° C.

Here, it is explained that if the first biological treatment step is performed in a range other than the above-described treatment conditions, the treatment of the ammonia-containing wastewater by the domesticated sludge of the biological treatment apparatus cannot simultaneously accumulate the nitrite content and suppress the generation of the nitrate.

The first biological treatment step described above is carried out in an aerobic environment, which can facilitate the domestication of sludge to effectively convert ammonia nitrogen containing ammonia nitrogen wastewater into nitrite. Therefore, in an embodiment, the first biological treatment step can selectively introduce an oxygen-containing gas into the ammonia-containing wastewater to make the dissolved nitrogen content of the ammonia-containing wastewater to be 0.5 mg/L to 6.0 mg/L, to help The domesticated sludge smoothly converts the ammonia nitrogen containing ammonia nitrogen wastewater into nitrite. In one illustration, the aforementioned oxygen-containing gas may be, for example, air or oxygen, and the introduced oxygen-containing gas may have a dissolved oxygen content of the ammonia-containing wastewater of, for example, 0.5 mg/L to 6.0 mg/L.

It is illustrated herein that the intermediate treated water after the first biological treatment step has a higher content of nitrite but a lower nitrate. In one illustration, the nitrite content of the intermediate treated water may, for example, be greater than 0 mg/L to 400 mg/L, but is free of ammonia nitrogen and the nitrate content is much less than one tenth of the nitrite content.

In other embodiments, after the first biological treatment step, the intermediate treatment water obtained above may be selectively subjected to a second biological treatment step, such as a short-range nitrification denitration step and/or an anaerobic ammonium oxidation step, to intermediate treatment. The nitrite of water is converted to nitrogen and denitrified. Short-range nitrification The nitric acid step and/or the anaerobic ammonium oxidation step can be carried out using any conventional means, and is not limited to the above, and is well known to those of ordinary skill in the art to which the present invention pertains, and is not further described.

The following examples are used to illustrate the application of the present invention, and are not intended to limit the present invention. Those skilled in the art can make various changes without departing from the spirit and scope of the present invention. Retouching.

Domesticated biologically activated sludge

Preparation example

First, the biologically activated sludge of the preparation example is an activated sludge obtained from aerobic treatment wastewater in a coking field of a medium steel plant, and the biological activated sludge is domesticated by coking wastewater to make the sludge reacted with the bioactive sludge and the coking wastewater. The residence time is from 20 days to 60 days, and the average hydraulic retention time of the coking wastewater can be, for example, from 1 day to 2 days to obtain domesticated sludge. The coking wastewater used in Example 1 includes a total phenol content of from 100 mg/L to 1000 mg/L, an ammonia nitrogen content of more than 0 mg/L to 600 mg/L, and a COD of from 1000 mg/L to 5000 mg/L. The biological activated sludge obtained in the preparation example was evaluated in various evaluation methods described later.

Biological processing step

Example 1

Example 1 is a domesticated sludge of the preparation example, which is introduced into the biological treatment equipment of FIG. 1 and reacted for at least 30 hours to obtain intermediate treated water, wherein the biological treatment conditions are as follows: the ammonia nitrogen concentration of the ammonia-containing wastewater is greater than 172 mg/L. Containing no nitrite, the MLSS of domesticated sludge is 5000mg/L, and the microbi ratio of ammonia-nitrogen wastewater to domesticated sludge is 0.034g NH ₃ -N/g MLSS, and the pH value of ammonia-containing water in biological treatment equipment is For pH 6.0 to 8.0, the ammonia-containing wastewater has a basicity of 50 mg/L to 650 mg/L of calcium carbonate in the biological treatment device, and the biological treatment step has an operating temperature of 35 °C. The content of nitrite and nitrate before and after the treatment of the ammonia-containing wastewater by the biological treatment step of the embodiment of the present invention is as shown in FIGS. 3 to 4 .

Example 2

Example 2 is a domesticated sludge of the preparation example, and the biological treatment step was carried out in the same manner as in Example 1 to obtain intermediate treated water, except that the biological treatment step of Example 2 was maintained using sodium hydrogencarbonate as an alkali agent. The alkalinity of the biological treatment step, which adds a basicity equivalent to 100 mg/L to 500 mg/L of calcium carbonate. A standard curve of the change in the content of nitrite and nitrate before and after the treatment of the ammonia-containing wastewater by the biological treatment step of Example 2 is shown in FIG.

Example 3

Example 3 was taken from the domesticated sludge of the preparation example, and the biological treatment step was carried out in the same manner as in Example 1 to obtain intermediate treated water, except that the biological treatment step of Example 3 used sodium hydrogencarbonate at different time points. As an alkaline agent, the pH of the ammonia-containing wastewater is maintained at a pH between 6.0 and 8.0 to maintain the alkalinity of the biological treatment step. A graph showing the nitrite content, the nitrate content, the ammonia nitrogen content, and the pH value of the alkalinity of the ammonia-containing wastewater by the biological treatment step of Example 3 at different times, as shown in FIG.

Comparative example 1

The biologically active sludge of Comparative Example 1 was an urban sewage treatment sludge taken from a Fengshanxi sewage treatment site, and the biological treatment step was carried out in the same manner as in Example 1 to obtain intermediate treated water, but the biological activity of Comparative Example 1 was carried out. The sludge was not domesticated by coking wastewater. The content of nitrite and nitrate in the ammonia-containing wastewater was treated by the biological treatment step of Comparative Example 1, as shown in FIG.

Comparative example 2

Comparative Example 2 was taken from the domesticated sludge of the preparation example, and the biological treatment step was carried out in the same manner as in Example 1 to obtain intermediate treated water, except that the biological treatment step of Comparative Example 2 was operated at a temperature of 20 °C. The content of nitrite and nitrate before and after the treatment of the ammonia-containing wastewater by the biological treatment step of Comparative Example 2 was as shown in FIG. 4 .

Evaluation method

Distribution of strains

The domesticated sludge obtained in Example 1 can be further analyzed by a 16s ribosomal DNA quantitative polymerase chain reaction (rDNA qPCR) quantitative method for long-term analysis of the strain distribution. Briefly, separated from the sludge embodiment of a domesticated bacteria, using a commercially available kit (e.g., ^{Ultra Clean TM Soil DNA Isolation kit;} MO BIO Laboratories, Inc., USA) which was extracted the DNA, the use of molecular cloning The technology selects a single clone of each target flora as a standard strain for quantitative analysis of each target flora. In the above molecular selection technique, the universal primers of EUB338f and 1392r can be paired with the target DNA to amplify the 16S rDNA sequence of the bacteria in the sludge, and the PCR gene product can be used as a commercially available vector. (eg pGEM ^® -T Easy Vector, pGEM ^® -T and pGEM ^® -T Easy Vector Systems; Promega Co., USA) is selected for selection with commercially available competent cells (eg, Oneshot DH5α cells). The aforementioned PCR quantitative analysis can be performed using a commercially available 16s rDNA PCR quantification kit (for example, SYBR ^® Premix Ex Taq ^TM experimental kit), and PCR quantitative analysis is performed according to the manufacturer's operation manual, and the results are shown in FIG. 2 . The above-mentioned isolated flora, extracted DNA, design of specificity primers, PCR reaction conditions, and quantitative analysis of PCR, etc., should be well known to those of ordinary skill in the art to which the present invention pertains, and will not be further described.

Please refer to FIG. 2 , which is a graph showing the number of bacteria of the main flora during the domestication of the domesticated sludge map according to an embodiment of the present invention. In Fig. 2, curve 201 represents the number of bacteria (%) of ammonia oxidizing bacteria, curve 203 represents the number of bacteria (%) of denitrifying bacteria, and curve 205 represents ammonia oxidizing bacteria, denitrifying bacteria and nitrous acid oxidizing bacteria. The number of bacteria (%) of other strains changed, and curve 209 represents the number of bacteria (%) of nitrous acid oxidizing bacteria.

It can be seen from the results of FIG. 2 that in the domesticated sludge of the embodiment, the growth curve 205 of other strains is higher, the growth curve of the denitrifying bacteria is 203, and the growth curve 201 of the ammoniacal bacteria is again, and the nitrous acid is oxidized. The growth curve 209 of the bacteria is less than 1%, which means that the domesticated sludge of the example can effectively accumulate the nitrite content and inhibit the production of nitrate.

The strains of the domesticated sludge of the examples were further analyzed, and the strains with the highest similarity in GenBank are shown in Table 1. The literature indicates that Phenanthrene biodegrading biofilm clone COB16 has phenolic degradation ability (Hung et al., 2013), Thiobacillus thioparus strain THI has cyanide degradation and denitrification capacity (Katayama et al., 1992), Alicycliphilus denitrificans BC strain BC, Comamonadaceae bacterium R042 Comamonas sp. ST18 has denitrification capacity (Mechichi et al., 2003; Weelink et al., 2008; Oosterkamp et al., 2011), Nitrosomonas sp. CNS332, and Comamonas sp. ST18 have ammonia oxidizing ability (Jin et al. , 2010; Srinandan et al., 2011), the above-referenced and listed references below are incorporated herein by reference. It is thus proved that the strains of the domesticated sludge used in this embodiment are the currently reported strains, and the relevant strains can be obtained from the above reference materials.

In Table 1, CSB1 is one of the strains isolated from the phenol-degraded semi-batch bioreactor, CSB2 is one of the strains isolated from the cave ecology, CSB8 is one of the strains isolated from coking wastewater, and CSB10 is separated. One of the strains from the anaerobic ammonium oxidation reactor, CSB11 is one of the strains isolated from the nitrification bioreactor, CSB14 is one of the strains isolated from the batch domesticated activated sludge, and CSB15 is isolated from the hospital by antibiotics. One of the strains polluting wastewater, CSB17 is one of the strains isolated from the contaminated aquifer of tetrachloroethane, CSB18 is one of the strains isolated from the weathered soil, and CSB24 is one of the strains isolated from the buried soil. CSB25 is one of the strains isolated from the soil of the buried field, and CSB29 is one of the strains isolated from the soil of aspen.

The references related to the species in Table 1 are as follows: Huang , Y., J. Zhang and L. Zhu (2013) Evaluation of The Application Potential of Bentonites in Phenanthrene Bioremediation by Characterizing The Biofilm Community. Bioresource Technology , 134 , 17-23.

Katayama-Fujimnra , Y., N. Tsuzaki and H. Kuraishi (1982) Ubiquinone, Fatty Acid and DNA Base Composition Determination as Guide to The Taxonomy of The Genus Thiobacillus. J. Gen. Microbiol. , 128 , 1599-1611.

Mechichi , T., E. Stackebrandt and G. Fuchs (2003) Alicycliphilus dentrificans gen. nov., sp. nov., a Cyclohexanol-Degrading, Nitrate-Reducing, β-Protobacterium. Int. J. Syst. Evol. Microbiol. , 53 , 147-152.

Weelink , SAB, NCG Tan, H. ten Broeke, C. van den Kieboom, W. van Doesburg, AAM Langenhoff, J. Gerritse, H. Junca and AJM Stams (2008) Appl. Environ. Microbiol. , 74 (21) , 6672-6681.

Oosterkamp , MJ, T. Veuskens, CM Plugge, AAM Langenhoff, J. Gerritse, WJH van Berkel, DH Pieper, H. Junca, LA Goodwin, HE Daligault, DC Bruce, JC Detter, R. Tapia, CS Han, ML Land , LJ Hauser, H. Smidt and AJM Stams (2011) Genome Sequences of Alicycliphilus denitrificans Strains BC and K601. J. Bacteriology , 193 (18), 5028-5029.

Jin , T., T. Zhang and QM Yan (2010) Characterization and Quantification of Ammonia-Oxidizing Archaea (AOA) and Bacteria (AOB) in a Nitrogen-Removing Reactor Using T-RFLP and q-PCR. Appl. Microbiol. Biotechnol . , 87 (3), 1167-1176.

Srinandan , CS, M. Shah, B. Patel and AS Nerurkar (2011) Assessment of Denitrifying Bacterial Composition in Activated Sludge. Bioresource Technology , 102 , 9481-9489.

2. The amount of nitrite production

Please refer to FIG. 3 to FIG. 4 , which illustrate the ammonia-containing wastewater containing the first embodiment of the invention (the two strips on the right side of FIGS. 3 and 4 ), the comparative example 1 (the two strips on the left side of FIG. 3 ) or a comparative example. 2 (The two strips on the left of Figure 4) The bar graph of the change in the content of nitrite and nitrate before and after the biological treatment step. The intermediate treated water obtained by the biological treatment step of Example 1 had a nitrite content of 583 mg/L and a nitrate content of 37 mg/L, as shown in Figs.

In contrast, the intermediate treated water obtained by the biological treatment step of Comparative Example 1 had a nitrite content reduced by 138 mg/L and a nitrate content of 300 mg/L, as shown in FIG. The biological activated sludge treatment of ammonia-containing wastewater can not simultaneously accumulate nitrite content and inhibit nitrate production.

The intermediate treated water obtained by the biological treatment step of Comparative Example 2 operating at 20 ° C had a nitrite content of 0 mg/L and a nitrate content of 2 Mg/L, as shown in Fig. 4, it is proved that the ammonia-containing wastewater is treated by the biologically active sludge of the preparation example but at the operating temperatures other than those of Examples 1 to 3, and the nitrite content and the nitrate inhibition are not simultaneously accumulated. produce.

3. Relationship between alkalinity and nitrite production

The ammonia-containing wastewater is treated by biological treatment steps with different alkalinity, and the content of nitrite and nitrate obtained can be controlled.

Please refer to FIG. 5 , which is a standard curve showing changes in the content of nitrite and nitrate before and after treatment with ammonia nitrogen wastewater in the biological treatment step of Example 2 of the present invention. In Fig. 5, the horizontal axis represents the amount of alkalinity added (corresponding to mg/L of calcium carbonate), the vertical axis represents the change in the content of nitrite and nitrate (mg/L) of ammonia-containing wastewater, and the curve 501 represents nitrous acid. A standard curve for the change in salt content, curve 503 represents a standard curve for the change in the content of nitrate. The relationship between the curve 501 and the curve 503 is as shown in the following formula (I): y = ax + b (I)

In the formula (I), x represents alkalinity, and y represents a content of nitrite or nitrate.

As can be seen from the results of FIG. 5, the a value of the curve 501 is 0.58, and the correlation coefficient R ² is 0.67, which represents a significant correlation between the alkalinity and the nitrite content. It also proves that the biological treatment step of the ammonia-containing wastewater can be confirmed. The nitrite content obtained by controlling the alkalinity is controlled by different alkalinity.

In contrast, the a value of the curve 503 is 0.04, and the correlation coefficient R ² is -0.26, which means that there is no significant correlation between the alkalinity and the nitrate content.

In addition, please refer to FIG. 6 , which is a graph showing the nitrite content, the nitrate content, the ammonia nitrogen content, and the pH value of the alkali treatment added at different times according to the biological treatment step of Example 3 of the present invention. In Fig. 6, the horizontal axis represents the treatment time (hours), and the vertical axis represents the nitrite content (mg/L), nitrate content (mg/L), ammonia nitrogen content (mg/L), and pH value of the ammonia-containing wastewater. The variation, wherein curve 601 represents the change in the content of nitrite, curve 603 represents the change in the content of nitrate, curve 605 represents the change in the content of ammonia nitrogen, curve 607 represents the change in pH, and arrow 611 represents the time point at which the alkalinity is added.

As can be seen from the results of FIG. 6 , as shown by the arrow 611, after the alkalinity is added at 4 hours, 24 hours, and 28 hours, the pH of the biological treatment step can be controlled not only between pH 6.0 and pH 8.0, but also Increasing the content of nitrite can reduce the content of ammonia nitrogen and inhibit the production of nitrate.

In the above embodiment, the number of samples per set of data is at least three (n ≧ 3).

In summary, Embodiments 1 to 3 apply the method for biologically treating ammonia-containing nitrogen wastewater of the present invention, and can effectively convert ammonia nitrogen containing ammonia-nitrogen wastewater into nitrite in an aerobic environment by using sludge domesticated by coking wastewater. And greatly reduce the production of nitrate. By controlling the alkalinity of the ammonia-containing wastewater, the obtained intermediate treatment water nitrite can be adjusted to a desired concentration to rapidly carry out the conventional short-cut nitrification denitration step and/or anaerobic ammonium oxidation step, thereby effectively reducing The energy consumption of the nitrification denitration program is known. In contrast, Comparative Examples 1 to 2 did not use the coking wastewater to domesticate the sludge, or did not use specific treatment conditions for biological treatment steps, and could not stably control the obtained intermediate treated water. The concentration of nitrite does not reduce the production of nitrate.

It should be noted that, although the present invention exemplifies a biological treatment step of a specific source of biological sludge, specific domestication conditions, and specific treatment conditions, the method for biologically treating ammonia-containing nitrogen wastewater of the present invention is described, but in the technical field to which the present invention pertains It is to be understood by those skilled in the art that the present invention is not limited thereto, and the biological treatment of ammonia-containing nitrogen wastewater of the present invention may also use biological sludge of other sources, other domestication conditions, and without departing from the spirit and scope of the present invention. Biological treatment steps for other processing conditions are performed.

It can be seen from the above embodiments of the present invention that the method for biologically treating ammonia-containing wastewater in the present invention has the advantages that the ammonia nitrogen contained in the ammonia-containing wastewater can be effectively converted into nitrite by using the sludge domesticated by the coking wastewater under an aerobic environment. To significantly reduce the production of nitrate. Secondly, by controlling the alkalinity of the ammonia-containing wastewater, the nitrite of the obtained intermediate treatment water can be adjusted to a desired concentration to rapidly carry out the conventional short-cut nitrification denitration step and/or the anaerobic ammonium oxidation step. Effectively reduce the energy consumption of the conventional nitrification and denitration program.

While the invention has been described above in terms of several embodiments, it is not intended to limit the scope of the invention, and the invention may be practiced in various embodiments without departing from the spirit and scope of the invention. The scope of protection of the present invention is defined by the scope of the appended claims.

201/203/205/209‧‧‧ Curve

Claims (13)

A method for biologically treating ammonia-containing wastewater comprises: carrying out a domesticating step of reacting a biologically activated sludge with a coking wastewater in an aerobic environment to obtain a domesticated sludge, wherein the domesticated sludge is ammonia-oxidizing bacteria The group is superior to the nitrous acid oxidizing bacteria, and the coking wastewater includes a total phenol content of 100 mg/liter (mg/L) to 1000 mg/L, an ammonia nitrogen content of more than 0 mg/L to 600 mg/L, and 1000 mg/L to 5000 mg/ L chemical oxygen demand (COD), one of the biological activated sludge sludge residence time is at least 20 days, and the domestication step is carried out for at least 180 days; the domesticated sludge is introduced into a treatment device, Forming a biological treatment device, wherein one of the domesticated sludge has a mixed liquid suspended solid (MLSS) of 1000 mg/L to 7000 mg/L; and performing a first biological treatment step to remove an ammonia-containing nitrogen The wastewater is introduced into the biological treatment device to oxidize the ammonia nitrogen of the ammonia-containing wastewater to nitrite to obtain an intermediate treatment water, wherein the ammonia nitrogen concentration of the ammonia-containing wastewater is greater than 0 mg/L to 400 mg/L, but not Asian Salt, and one of the first biological treatment step conditions include: ammonia-containing wastewater from the food microstructure than one domesticated sludge 0g NH ₃ -N / g MLSS to 0.2g NH ₃ -N / g MLSS, The ammonia-nitrogen-containing wastewater has a pH value of pH 6.0 to 8.0 in the biological treatment device, and the alkalinity of the ammonia-containing wastewater in the biological treatment device is equivalent to 50 mg/L to 650 mg/L of calcium carbonate, and the One of the first biological treatment steps has an operating temperature of 20 ° C to 40 ° C, and wherein the intermediate treated water has a nitrite content of greater than 0 mg/L to 400 mg/L and a nitrate content of less than the nitrite content. one. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein the strain of the domesticated sludge comprises α- Proteobacteria of Oligotropha sp. and Seda Sandarcinobacter sp. , β- Proteobacteria sp. , Alicycliphilus sp. , Thiobacillus sp. , nitrite nitrite ( Nitrosomonas sp. ), Comamonas sp. , Ottowia sp. and Pusillimonas sp. , Firmicutes Eubacterium sp. and any combination of the above. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein the sludge residence time is from 20 days to 60 days in the domesticating step. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein in the domesticating step, one of the coking wastewaters has an average hydraulic retention time of from 1 day to 2 days. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein the treatment device is an aeration tank or a fluidized bed. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 5, wherein the domestic sludge is suspended and cultured in the aeration tank. Biological treatment according to item 5 of the patent application scope A method for containing ammonia nitrogen wastewater, wherein the domestic sludge is loaded in a plurality of biological carriers, and the biological carriers are cultured in the aeration tank or the fluidized bed. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 5, wherein the fluidized bed is an aerobic upflow fluidized bed. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein the alkalinity of the ammonia-containing wastewater is provided by an alkali agent, and the alkali agent is sodium hydrogencarbonate or sodium carbonate. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein the first biological treatment step further comprises introducing an oxygen-containing gas into the ammonia-containing wastewater to make a dissolved oxygen content of the ammonia-containing wastewater 0.5 mg/L to 6.0 mg/L. A method of biologically treating ammonia-containing nitrogen wastewater according to claim 10, wherein the oxygen-containing gas is air or oxygen. The method of biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein in the first biological treatment step, the operating temperature of the first biological treatment step is from 30 ° C to 35 ° C. The method for biologically treating ammonia-containing nitrogen wastewater according to claim 1, wherein after the first biological treatment step, further comprising: performing a second biological treatment step to perform a short-range nitrification and denitration of the intermediate treated water And/or an anaerobic ammonium oxidation step to convert the nitrite of the intermediate treated water to nitrogen.