TWI532682B - System for removing hydrogen peroxide from ammonia-nitrogen wastewater and the method thereof - Google Patents

Description

System for removing hydrogen peroxide in ammonia nitrogen waste liquid and method thereof

The invention relates to a treatment system and method for ammonia nitrogen waste liquid, in particular to a treatment system and a method for removing hydrogen peroxide in ammonia nitrogen waste liquid before the ammonia nitrogen recovery operation by distillation.

According to the ammonia nitrogen (NH ₃ -N) waste liquid, it is one of the main types of wastewater in the semiconductor industry. Among them, hydrogen peroxide (H ₂ O ₂ ) has an explosion hazard in high temperature environment. The ammonia nitrogen component in the waste liquid must be reduced to a proper concentration in the ammonia nitrogen waste liquid to safely carry out the ammonia nitrogen waste liquid subsequent recovery process at a high temperature.

The main factors affecting the decomposition of hydrogen peroxide are temperature, pH value and catalytic impurities. Among them, the decomposition rate of hydrogen peroxide in hot alkaline solution is fast, and increasing the metal ions in the waste liquid can accelerate the decomposition of hydrogen peroxide. Therefore, there is currently a method of adding activated carbon, manganese dioxide (MnO ₂ ) or other chemical agents to decompose and remove hydrogen peroxide in the waste liquid, but this method not only needs to increase the cost of the additive consumables, but also ammonia nitrogen in the ammonia nitrogen waste liquid. The composition may be adsorbed by or reacted with the additive, resulting in a more complicated and difficult process for recycling the ammonia nitrogen waste liquid.

It is worth noting that hydrogen peroxide has the property of being decomposable by light having a wavelength of 320 to 380 nm. Thus, the inventors of the present invention have considered the above-mentioned ammonia nitrogen waste liquid to be treated by distillation to recover the problem and the characteristics of hydrogen peroxide. It is necessary to propose an ultraviolet (UV light) irradiation as a pretreatment for ammonia nitrogen waste liquid recovery. The main program for removing hydrogen peroxide from ammonia nitrogen waste liquid and its method.

The object of the present invention is to provide a system for removing hydrogen peroxide in ammonia nitrogen waste liquid and a method thereof, which mainly utilize ultraviolet (UV) to decompose hydrogen peroxide (H ₂ O ₂ ) into water and oxygen to achieve removal. The purpose of hydrogen peroxide in ammonia nitrogen (NH ₃ -N) waste liquid.

Another object of the present invention is to reduce the dissolved oxygen content of the waste liquid by introducing nitrogen gas into the ammonia nitrogen waste liquid which is irradiated with ultraviolet rays, thereby achieving the purpose of accelerating the decomposition efficiency of hydrogen peroxide.

In order to achieve the above object, a system for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to the present invention is provided for removing a hydrogen peroxide component in a high concentration hydrogen peroxide ammonia nitrogen waste liquid, wherein the system comprises : an ammonia nitrogen waste liquid filtration section, which is input with the ammonia nitrogen waste liquid containing high concentration hydrogen peroxide, the ammonia nitrogen waste liquid filtration section is used for removing suspended solids in the ammonia nitrogen waste liquid containing high concentration hydrogen peroxide, and outputting a filter a high concentration ammonia nitrogen waste liquid; an ammonia nitrogen waste liquid tank having a high hydrogen peroxide concentration for storing the filtered high concentration ammonia nitrogen waste liquid; a batch reaction section having a reaction tank and an analysis controller, the analysis control The device is electrically connected to a UV lamp tube, a hydrogen peroxide sensor and a liquid level sensing unit disposed inside the reaction tank, and the UV lamp tube is covered with a quartz sleeve to quantify the batch reaction section. The filtered high-concentration ammonia nitrogen waste liquid is input into the reaction tank and irradiated to the UV lamp tube; a low-hydrogen peroxide concentration ammonia nitrogen waste liquid tank is provided for storing the low-concentration of the output of the batch reaction section. Ammonia nitrogen waste of hydrogen peroxide liquid.

Further, a method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to the present invention, the method steps comprising: (a) a filtration step, (b) a batch inflow step, (c) a UV irradiation step, and (d) discharging In the step of UV irradiation, a UV lamp tube of a jacket quartz sleeve and a hydrogen peroxide sensor are disposed in the reaction tank and electrically connected to an analysis controller, so that the analysis controller and the device are configured. One of the liquid level sensing units in the reaction tank is electrically connected, and the analysis controller activates the UV lamp to emit ultraviolet light after the reaction tank is filled, so that the hydrogen peroxide in the filtered high concentration ammonia nitrogen waste liquid is subjected to It is excited by ultraviolet radiation to be decomposed into water and oxygen.

A method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to the present invention, wherein the UV irradiation step is carried out in conjunction with a nitrogen aeration step of introducing a nitrogen gas into the reaction tank, After filtration, the high concentration ammonia nitrogen waste liquid is aerated by the nitrogen gas stream to reduce the dissolved oxygen amount in the wastewater.

The preferred embodiments of the present invention are described in detail with reference to the accompanying drawings.

First, please refer to FIG. 2 and FIG. 2, and the present invention provides a system for removing hydrogen peroxide in ammonia nitrogen waste liquid and a preferred embodiment thereof, such as the system shown in FIG. The invention comprises an ammonia nitrogen waste liquid filter section S, an ammonia nitrogen waste liquid tank T, a batch reaction section R and a nitrogen gas aeration section A. Table 1 and Table 2 below indicate the number and name of each section of the system, and each The fluid number between the segments and their names:

As shown in Fig. 1, the ammonia nitrogen waste liquid filtration section S of the system for removing hydrogen peroxide in the ammonia nitrogen waste liquid is used for filtering a ammonia nitrogen waste liquid 1 containing a high concentration of hydrogen peroxide to remove the waste liquid. Suspending solids, increasing the transmittance of the waste liquid. In the present embodiment, the ammonia nitrogen waste liquid filter section S can achieve a filtering effect for the filter core type or the filter bag type filter device; the ammonia nitrogen waste liquid tank having the high hydrogen peroxide concentration The T1 system is for storing the high concentration ammonia nitrogen waste liquid 2 filtered by the ammonia nitrogen waste liquid filter section S to the batch reaction section R; as shown in FIG. 2, the batch reaction section R mainly has a reaction tank 10 For inputting the filtered high-concentration ammonia nitrogen waste liquid 2, the reaction tank 10 is internally provided with a UV lamp tube 20 and a hydrogen peroxide sensor 40, the UV lamp tube 20 is jacketed with a quartz sleeve 30, and an analysis controller is provided. 50 is electrically connected to the UV lamp tube 20, the hydrogen peroxide sensor 40, and a liquid level sensing unit 51 disposed in the reaction tank 10. In the embodiment, the hydrogen peroxide is irradiated by ultraviolet rays. Water (H ₂ O) and oxygen (O ₂ ) are formed as in the following reaction formulas (1) and ( ₂ ): H ₂ O ₂ + hv → 2OH‧ (1)

2OH‧+2OH ^- →H ₂ O+O ₂ (2)

The nitrogen aeration section A is for outputting a nitrogen stream 3 to the reaction tank 10 of the batch reaction section R, so that the filtered high concentration ammonia nitrogen waste liquid 2 is in contact with the nitrogen stream 3 for aeration; due to the hydrogen peroxide itself Easy reaction formula: 2H ₂ O _{2 (1)} → 2H ₂ O ₍₁₎ + O _{2 (g)} decomposes to generate oxygen, and after ultraviolet irradiation, the amount of dissolved oxygen in the waste liquid will increase rapidly, but in the waste When the amount of dissolved oxygen reaches a saturated dissolved oxygen value, the decomposition rate of hydrogen peroxide is lowered. Therefore, the present invention uses the nitrogen aeration section A to pass nitrogen gas into the waste liquid to reduce the dissolved oxygen amount, so that the ammonia nitrogen waste liquid is beneficial to the ammonia nitrogen component. Under the environmental conditions, the hydrogen peroxide is continuously reacted by the reaction formulas (1) and (2); the ammonia hydrogen waste tank T2 having the low hydrogen peroxide concentration is used for storing the output of the batch reaction section R. The ammonia nitrogen waste liquid 4 of the low concentration hydrogen peroxide is disposed, and an ammonia nitrogen sensor T21 is electrically connected to the analysis controller 50 in the ammonia nitrogen waste liquid tank T2 of the low hydrogen peroxide concentration.

The above is the main components of the system of the present invention and its configuration description, as for The mode of operation of the method of the invention and its efficacy are described below.

Referring to FIG. 3, the steps of the method for removing hydrogen peroxide in the ammonia nitrogen waste liquid of the present invention include: (a) filtration step S1, (b) batch inflow step S2, (c) UV irradiation step S3, and (d) discharging step S4, wherein: (a) filtering step S1: inputting a high-concentration hydrogen peroxide-containing ammonia nitrogen waste liquid 1 into an ammonia nitrogen waste liquid filtering section S to filter suspended solids, and outputting a filtered high concentration Ammonia nitrogen waste liquid 2 to a high hydrogen peroxide concentration ammonia nitrogen waste liquid tank T1 is stored; (b) Batch inflow step S2: a certain amount of ammonia nitrogen waste liquid is outputted from the high hydrogen peroxide concentration ammonia nitrogen waste liquid tank T1 In the reaction tank 10 of one batch reaction section R; in the present embodiment, the quantitative ammonia nitrogen waste liquid 21 outputted by the batch inflow step S2 has a hydrogen peroxide concentration of 300 to 6000 mg/liter, and 50 Ammonia nitrogen concentration (NH ₃ -N) to 2000 mg / liter; (c) UV irradiation step S3: a UV lamp tube 20 of a jacket quartz sleeve 30 and a hydrogen peroxide sensor 40 are disposed in the reaction tank 10 And electrically connected to an analysis controller 50, and the analysis controller 50 is electrically connected to a liquid level sensing unit 51 disposed in the reaction tank 10, After the reaction tank 10 is filled, the analysis controller 50 activates the UV lamp tube 20 to emit ultraviolet rays, so that the hydrogen peroxide in the filtered high-concentration ammonia nitrogen waste liquid 2 is excited by ultraviolet irradiation to be decomposed into water and oxygen; In the example, the UV lamp 20 of the UV irradiation step S3 is irradiated for 1 to 120 minutes, and preferably irradiated for 90 to 120 minutes; (d) discharging step S4: oxidizing the UV lamp 20 in the waste liquid The hydrogen concentration is lower than when the hydrogen peroxide sensor 40 detects the lowest value, and the reaction tank 10 outputs a ammonia nitrogen waste liquid 4 containing a low concentration of hydrogen peroxide to a low ammonia hydrogen peroxide solution T2 storage. Set.

The UV irradiation step S3 of the method of the present invention is preferably carried out in combination with a nitrogen aeration step S31. The nitrogen aeration step S31 is mainly to input a nitrogen stream 3 into the reaction tank 10 to make the filtered high concentration ammonia nitrogen. The waste liquid 2 is aerated by the nitrogen gas stream 3 to reduce the dissolved oxygen amount in the waste water; in the present embodiment, the nitrogen gas stream 3 aerates the liquid ammonia per liter waste liquid at a flow rate of 10 ml per minute, thereby If the reaction tank 10 of the present invention can input 100 to 1000 liters of the quantitatively filtered high-concentration ammonia nitrogen waste liquid 2, the flow rate of the nitrogen gas stream 3 is 1000 to 10000 ml per minute to the waste liquid for aeration; in addition, the nitrogen gas The aeration step S31 is preferably performed intermittently with the UV irradiation step S3, and the operation mode is that the UV lamp tube 20 continuously irradiates the filtered high-concentration ammonia nitrogen waste liquid 2 in the reaction tank 10, and is per 5 The minute UV irradiation reaction time was combined with the nitrogen aeration time of 1 minute.

Please also refer to FIG. 4 to illustrate the present invention in which a hydrogen fluoride (H ₂ O ₂ ) irradiated with ultraviolet rays (UV) is irradiated by an ammonia nitrogen waste liquid generated from a semiconductor process. Concentration change of curve L1) and ammonia nitrogen (NH ₃ -N) component (curve L2), and hydrogen peroxide (H ₂ O ₂ ) (curve L3) and ammonia nitrogen (NH ₃ -N) component aerated with ultraviolet light and nitrogen gas (Curve L4) concentration change; wherein the water-nitrogen data of the ammonia nitrogen waste liquid is: the pH value of the waste liquid is 8.7, the ammonia nitrogen concentration is 156 mg/liter, and the hydrogen peroxide concentration is 550 mg/liter, which is obvious in the waste liquid. Suspended solids on white.

Example 1

First, a waste liquid sample is filtered to remove the suspended matter through the filtering step S1, and 750 ml of the waste liquid sample is flowed into the reaction tank 10 in the batch inflow step S2, and the ultraviolet irradiation is continuously and uninterruptedly irradiated in the UV irradiation step S3. After 120 minutes of the waste liquid sample, the waste liquid sample was analyzed as shown in the curve L1, L2 and Table 3 of Fig. 4, wherein the hydrogen peroxide concentration was drastically decreased to 25 mg/liter when the irradiation was continued for 90 minutes, and the ammonia nitrogen component was The concentration decreased slightly to 140 mg / liter, showing a hydrogen peroxide removal rate of 95%, and ammonia nitrogen reduction of about 10%, confirming that after a long time of UV / H ₂ O ₂ reaction, the ammonia nitrogen in the waste liquid is limited to a limited extent. It does not affect the subsequent distillation recovery of ammonia nitrogen waste liquid.

Example 2

The filtration step S1 and the batch inflow step S2 are carried out in the same manner as in the first embodiment. In the UV irradiation step S3, the waste liquid sample is continuously irradiated with ultraviolet rays for 120 minutes without interruption, and intermittently blended with the nitrogen aeration step S31 to ultraviolet rays every 5 minutes. The irradiation reaction time was matched with the nitrogen aeration time of 1 minute, and the waste liquid sample was analyzed as shown by the curves L3, L4 and Table 3 in Fig. 4, and the concentration of hydrogen peroxide in the waste liquid was greatly reduced until the reaction continued to 90 minutes. 1 mg / liter, the ammonia nitrogen concentration decreased slightly to 150 mg / liter, it can be seen that the hydrogen peroxide removal rate of the waste liquid sample is 98%, showing that the hydrogen peroxide removal rate is better than the ultraviolet light removal rate of the first embodiment. And the loss rate of the ammonia nitrogen component is also preferred.

In summary, the system and method for removing hydrogen peroxide in the ammonia nitrogen waste liquid disclosed in the present invention can effectively remove the hydrogen peroxide in the ammonia nitrogen waste liquid, and can also raise the wastewater before the ammonia nitrogen component loss rate is extremely low. The quality of recycling.

Although the present invention has been disclosed in its preferred embodiments, it is not intended to limit the present invention, and it is possible to make some modifications and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

S‧‧‧Ammonia nitrogen waste liquid filtration section

R‧‧‧ batch reaction section

A‧‧‧Nitrogen aeration section

T1‧‧‧Ammonia nitrogen waste tank with high hydrogen peroxide concentration

T2‧‧‧Ammonia nitrogen waste tank with low hydrogen peroxide concentration

T21‧‧‧ ammonia nitrogen sensor

1‧‧‧Ammonia nitrogen waste liquid with high concentration of hydrogen peroxide

2‧‧‧High concentration ammonia nitrogen waste liquid after filtration

21‧‧‧Quantitative ammonia nitrogen waste

3‧‧‧Nitrogen flow

4‧‧‧Ammonia nitrogen waste liquid with low concentration of hydrogen peroxide

10‧‧‧Reaction tank

20‧‧‧UV lamp

30‧‧‧Quartz casing

40‧‧‧Hydrogen peroxide sensor

50‧‧‧Analysis controller

51‧‧‧Level sensing unit

S1‧‧‧Filter step

S2‧‧‧ batch inflow step

S3‧‧‧UV irradiation step

S31‧‧‧Aeration step

S4‧‧‧ emission steps

Fig. 1 is a schematic diagram showing the flow of a system for removing hydrogen peroxide from ammonia nitrogen waste liquid according to the present invention.

Figure 2 Schematic diagram of the UV irradiation reaction tank of the system of the present invention

Figure 3 shows the steps of the method for removing hydrogen peroxide from ammonia nitrogen waste liquid Figure.

Fig. 4 is a graph showing the data of changes in hydrogen peroxide and ammonia nitrogen concentration in the system of the present invention without an aeration step and an aeration step.

S‧‧‧Ammonia nitrogen waste liquid filtration section

R‧‧‧ batch reaction section

T1‧‧‧Ammonia nitrogen waste tank with high hydrogen peroxide concentration

T2‧‧‧Ammonia nitrogen waste tank with low hydrogen peroxide concentration

A‧‧‧Nitrogen aeration section

1‧‧‧Ammonia nitrogen waste liquid with high concentration of hydrogen peroxide

2‧‧‧High concentration ammonia nitrogen waste liquid after filtration

21‧‧‧Quantitative ammonia nitrogen waste

3‧‧‧Nitrogen flow

4‧‧‧Ammonia nitrogen waste liquid with low concentration of hydrogen peroxide

Claims (10)

A system for removing hydrogen peroxide from an ammonia nitrogen waste liquid for removing a hydrogen peroxide component in a high concentration hydrogen peroxide ammonia nitrogen waste liquid, wherein the system comprises: an ammonia nitrogen waste liquid filtration section, which is input with the high concentration An ammonia nitrogen waste liquid of hydrogen peroxide, the ammonia nitrogen waste liquid filtration section is for removing suspended solids in the ammonia nitrogen waste liquid containing high concentration of hydrogen peroxide, and outputting a filtered high concentration ammonia nitrogen waste liquid; a high hydrogen peroxide concentration An ammonia nitrogen waste liquid tank for storing the filtered high concentration ammonia nitrogen waste liquid; a batch reaction section having a reaction tank and an analysis controller, the analysis controller and a UV lamp tube disposed inside the reaction tank, A hydrogen peroxide sensor and a liquid level sensing unit are electrically connected, and the UV lamp tube is jacketed with a quartz sleeve, so that the batch reaction section is quantitatively input into the filtered high concentration ammonia nitrogen waste liquid to the reaction thereof. The tank is irradiated with the UV lamp; a ammonia nitrogen waste tank having a low hydrogen peroxide concentration for storing an ammonia nitrogen waste liquid containing a low concentration of hydrogen peroxide in the output of the batch reaction section. The system for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to claim 1, wherein the ammonia nitrogen waste liquid filtration section is a filter core type or a filter bag type filtering device. Hydrogen peroxide in ammonia-depleted waste liquid as described in claim 1 The system, wherein the ammonia nitrogen waste tank having the low hydrogen peroxide concentration is provided with an ammonia nitrogen sensor electrically connected to the analysis controller. The system for removing hydrogen peroxide from an ammonia nitrogen waste liquid according to claim 1, wherein the batch reaction section is connected to a nitrogen aeration section, and the nitrogen aeration section outputs a nitrogen gas flow to the batch. In the reaction tank of the reaction section, the filtered high concentration ammonia nitrogen waste liquid is brought into contact with the nitrogen stream to aerate. A method for removing hydrogen peroxide in an ammonia nitrogen waste liquid, the method steps comprising: (a) a filtering step: inputting a ammonia nitrogen waste liquid containing a high concentration of hydrogen peroxide into an ammonia nitrogen waste liquid filtration section to filter suspended solids, and outputting a filtered high concentration ammonia nitrogen waste liquid is stored in a ammonia nitrogen waste liquid tank having a high hydrogen peroxide concentration; (b) a batch inflow step: outputting a certain amount of ammonia nitrogen waste liquid from the ammonia nitrogen waste liquid tank having the high hydrogen peroxide concentration Up to one of the reaction zones of the batch reaction section; (c) UV irradiation step: a UV lamp tube with a jacketed quartz sleeve and a hydrogen peroxide sensor are disposed in the reaction tank and electrically connected to an analysis controller Sexually connecting, the analysis controller is electrically connected to a liquid level sensing unit disposed in the reaction tank, and the analysis controller starts the UV lamp to emit ultraviolet light after the reaction tank is filled, and the high concentration is filtered. Ammonia nitrogen waste liquid, the hydrogen peroxide component in the filtered high concentration ammonia nitrogen waste liquid is excited to be decomposed into water and oxygen; (d) discharging step: making the UV lamp tube in the waste liquid hydrogen peroxide concentration The irradiation is stopped when the lowest value of the hydrogen peroxide sensor is detected. The reaction tank outputs a ammonia nitrogen waste liquid containing a low concentration of hydrogen peroxide to a ammonia nitrogen waste liquid tank with a low hydrogen peroxide concentration. The method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to claim 5, wherein the UV irradiation step is performed by a nitrogen aeration step of inputting a nitrogen gas flow to the reaction tank. In the middle, the filtered high-concentration ammonia nitrogen waste liquid is aerated by the nitrogen gas stream to reduce the dissolved oxygen amount in the wastewater. The method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to claim 6, wherein the nitrogen gas flow rate of the nitrogen aeration step is aerated by introducing a nitrogen gas amount of 10 ml/min per liter of the ammonia nitrogen waste liquid. . The method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to the sixth aspect of the patent application, wherein in the UV irradiation step and the nitrogen aeration step, the filtered high concentration ammonia nitrogen waste liquid in the reaction tank is the UV The tube was continuously irradiated for 90 to 120 minutes, and the UV irradiation reaction time was mixed with the nitrogen aeration time for 1 minute every 5 minutes. The method for removing hydrogen peroxide from an ammonia nitrogen waste liquid according to claim 5, wherein the quantitative ammonia nitrogen waste liquid outputted by the batch inflow step has a hydrogen peroxide concentration of 300 to 6000 mg/liter, and Ammonia nitrogen concentration (NH ₃ -N) of 50 to 2000 mg / liter. The method for removing hydrogen peroxide in an ammonia nitrogen waste liquid according to claim 5, wherein the UV lamp irradiation time of the UV irradiation step is 1 to 120 minutes.