CN110078263A - High ammonia nitrogen and high hardness sewage pretreatment device, processing system and processing method - Google Patents

Abstract

The invention provides a pretreatment device, a treatment system and a treatment method for high ammonia nitrogen and high hardness wastewater. The pretreatment device includes: a buffer blowing tank, an aeration equipment and a coagulation tank, the buffer blowing tank has an inlet of an alkaline conditioner, a waste water inlet and an outlet of the buffer blowing tank; the aeration device is arranged at the bottom of the buffer blowing tank The coagulation tank includes a coagulant inlet, a water inlet of the coagulation tank and a water outlet of the coagulation tank; wherein, the outlet of the buffer blowing tank is connected with the water inlet of the coagulation tank. By setting aeration equipment at the bottom of the buffer stripping tank, the alkaline regulator added from the inlet of the alkaline regulator can fully mix and react with the wastewater with high ammonia nitrogen and high hardness, and part of the calcium and magnesium ions in the wastewater are absorbed by the alkaline regulator. It is converted into precipitates for removal, and ammonia nitrogen can also be initially removed. Therefore, the total hardness removal efficiency of this device is high, which greatly reduces the impact on subsequent biochemical treatment and underwater equipment scaling.

Description

High ammonia nitrogen high hardness wastewater pretreatment device, treatment system and treatment method

technical field

The invention relates to the technical field of environmental protection, in particular to a pretreatment device, a treatment system and a treatment method for high ammonia nitrogen and high hardness wastewater.

Background technique

The coal chemical gasification unit discharges a large amount of production wastewater during the production process. Among them, the indicators of the wastewater are as follows: total hardness 900-1200mg/L, ammonia nitrogen 300-400mg/L, COD 600-1100mg/L, turbidity 45-78NTU, Alkalinity 15-21mmol/L, pH 8.2-8.6. These chemical wastewater have the following characteristics: high hardness, high ammonia nitrogen, large amount of wastewater and difficult treatment (so this type of wastewater is also called high ammonia nitrogen high hardness wastewater), which has a great impact on subsequent biochemical treatment and underwater equipment scaling.

The most commonly used processing method at present is the lime softening method, but this method has the following problems:

(1) The total hardness removal effect is low, only reaching 20-30%, and the subsequent inorganicization of the biochemical system and the fouling of underwater equipment have a greater impact.

(2) There is no removal effect on ammonia nitrogen.

(3) Fully automatic control cannot be realized.

Therefore, it is still necessary to improve the treatment method of this high-ammonia-nitrogen high-hardness wastewater.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a high ammonia nitrogen high hardness wastewater pretreatment device, treatment system and treatment method to solve the problem of low total hardness removal effect in the treated wastewater in the prior art.

In order to achieve the above object, according to one aspect of the present invention, a high ammonia nitrogen high hardness wastewater pretreatment device is provided, the pretreatment device includes: buffer blowing tank, aeration equipment and coagulation tank, buffer blowing tank has alkali The inlet of the neutral conditioner, the inlet of waste water and the outlet of the buffer blowing tank; the aeration equipment is arranged at the bottom of the buffer blowing tank; the coagulation tank includes the inlet of coagulant, the inlet of coagulation tank and the outlet of coagulation tank; among them, the buffer The water outlet of the blowing tank is connected with the water inlet of the coagulation tank.

Further, the alkaline conditioner inlet includes: a first conditioner inlet and a second conditioner inlet, the first conditioner inlet communicates with the first conditioner input line; the second conditioner inlet communicates with the second conditioner input line; Preferably, along the input direction of the first conditioner, the first control agent and the first metering pump are sequentially arranged on the first conditioner input line; preferably, along the input direction of the second conditioner, the second conditioner input line The second control element and the first pH monitoring element are sequentially arranged on it.

Further, the coagulant inlet is communicated with the coagulant input line; preferably, a first coagulation inlet and a second coagulation inlet are arranged in parallel on the coagulant input line; preferably, a coagulant input line is also provided with There is a third controller and a second metering pump, and the third controller and the second metering pump are used to control and measure the dosage of the first coagulation inlet and the second coagulation inlet respectively; preferably, the coagulant input pipeline A mixing device is also provided on the top, and along the flow direction of the coagulant, the first coagulation inlet and the second coagulation inlet communicate with the coagulant inlet through the mixing device.

Further, the water inlet of the coagulation tank is connected with the water inlet pipeline of the coagulation tank, and a fourth controller and a third metering pump are sequentially arranged on the water inlet pipeline of the coagulation tank along the water flow direction, and the water inflow signal measured by the third metering pump is transmitted to the first Four controllers, the fourth controller is electrically connected to the third controller and converts the water inflow signal measured by the third metering pump into an electrical signal and transmits it to the third controller, and the third controller adjusts the second metering pump through the electrical signal added value.

Further, the pretreatment device also includes a sludge mixing tank. Along the direction of water flow, the sludge mixing tank is arranged between the buffer stripping tank and the coagulation tank; preferably, the sludge mixing tank is provided with a sludge return port; preferably, The sludge return port communicates with the sludge return pipeline, and the sludge return pipeline is provided with a fifth controller and a fourth metering pump connected in sequence.

Further, the pretreatment device also includes a sedimentation tank, which communicates with the coagulation tank and is arranged downstream of the coagulation tank along the water flow direction.

Further, the sedimentation tank includes an outlet pipeline, and a second pH monitoring element is arranged on the outlet pipeline; preferably, the second pH monitoring element is electrically connected with the first control element and the second control element, and monitors the second pH monitoring element to The pH value is fed back to the first control element and the second control element, thereby controlling the addition amount of the regulator at the first regulator inlet and the second regulator inlet.

Further, the sedimentation tank includes an outlet pipeline, on which a hardness meter is arranged, and the hardness meter is electrically connected with the first control element and the second control element, and feeds back the hardness value monitored by the hardness meter to the first control element and the second control element. A control element, thereby controlling the addition amount of the regulator at the first regulator inlet and the second regulator inlet.

Further, the pretreatment device also includes: a neutralization tank, the neutralization tank includes an acid dosing port and a neutralized water output pipeline, preferably, the acid dosing port communicates with the acid input pipeline, and a fifth Metering pump; preferably, a third pH monitoring element is provided on the neutralization water output pipeline, and both the third pH monitoring element and the fifth metering pump are electrically connected to the sixth controller.

In order to achieve the above object, according to one aspect of the present invention, a high ammonia nitrogen high hardness wastewater treatment system is provided, the system includes: a pretreatment device and a biochemical device, the pretreatment device is any one of the above high ammonia nitrogen high hardness wastewater pretreatment device ; The biochemical device is arranged downstream of the pretreatment device.

According to another aspect of the present invention, a method for pretreatment of high ammonia nitrogen and high hardness wastewater is provided, the pretreatment method comprising: adding an alkaline conditioner to the high ammonia nitrogen and high hardness wastewater to form the first mixed wastewater; The waste water is subjected to aeration treatment to obtain the first dehardness and ammonia nitrogen removal wastewater; the first dehardness and ammonia nitrogen removal wastewater is subjected to coagulation treatment to obtain the coagulation treatment wastewater.

Further, the alkaline conditioner includes sodium hydroxide and sodium carbonate; preferably, the dosage of sodium hydroxide is preferably 1800-3000ppm, more preferably 2200-2500ppm; preferably, the dosage of sodium carbonate is 100 ~250ppm, more preferably 150~200ppm; preferably, the time of aeration treatment is 1.5~5 hours, preferably 2~3 hours.

Further, add a coagulant to the first dehardened and deammoniated nitrogen wastewater for coagulation treatment to obtain coagulation treatment wastewater; wherein the coagulant includes PAC and PAM; preferably, the dosage of PAC is 20-40ppm, More preferably 25-35ppm; preferably, the dosage of PAM is 0.2-0.8ppm, more preferably 0.4-0.6ppm.

Further, before performing coagulation treatment on the first dehardened and deammonized nitrogen wastewater, the pretreatment method further includes: a step of mixing sludge into the first dehardened and deammonized nitrogen wastewater.

Further, after obtaining the coagulated wastewater, the pretreatment method also includes: carrying out sedimentation treatment on the coagulated wastewater to separate the muddy water to obtain deslimed wastewater; preferably, after obtaining the deslimed wastewater, the pretreatment method also includes: Adjust the pH value of the sludge wastewater to obtain the first step of adjusting the wastewater; more preferably, adjust the pH value of the deslimed wastewater by adjusting the amount of sodium hydroxide added to the high ammonia nitrogen high hardness wastewater, and further preferably adjust the deslimed wastewater The pH value is 10.2~10.5.

Further, after obtaining the first adjusted wastewater, the pretreatment method also includes: neutralizing the first adjusted wastewater to obtain neutralized wastewater; preferably, the pH value of the neutralized wastewater is 6-9, more preferably the pH value is 8 to 8.5; preferably, the neutralization treatment is performed by adding an acid solution to the first adjusted wastewater, more preferably, the acid solution is sulfuric acid.

Applying the technical scheme of the present invention, by arranging aeration equipment at the bottom of the buffer blowing tank, the alkaline regulator added from the inlet of the alkaline regulator is fully mixed and reacted with the wastewater with high ammonia nitrogen and high hardness, and part of the calcium, Magnesium ions are converted into precipitates by alkaline regulators for removal. In addition, part of the ammonia gas overflows out of the water body, so that the total hard removal rate in the wastewater is high, and ammonia nitrogen can also be initially removed; and then further through the coagulation tank The wastewater discharged from the outlet of the buffer blowing tank is further coagulated and precipitated, so that the turbidity of the wastewater discharged from the outlet of the coagulation tank is further reduced. The device is used for pretreatment of high ammonia nitrogen and high hardness wastewater, and the total hardness removal efficiency is high, which greatly reduces the impact on subsequent biochemical treatment and underwater equipment scaling.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached image:

Fig. 1 shows the structural representation of the pretreatment device of the high ammonia nitrogen high hardness wastewater according to a preferred embodiment of the present invention;

Fig. 2 shows a schematic structural view of the buffer blowing pool according to a preferred embodiment of the present invention;

Fig. 3 shows a schematic structural view of the coagulation tank according to a preferred embodiment of the present invention; and

Fig. 4 shows a schematic structural diagram of a neutralization tank according to a preferred embodiment of the present invention.

Wherein, the above-mentioned accompanying drawings include the following reference signs:

10. Buffer stripping tank; 20. Aeration equipment; 30. Coagulation tank; 40. Sludge mixing tank; 50. Sedimentation tank; 60. Neutralization tank;

11. Wastewater inlet; 12. Outlet of buffer blowing tank; 13. First regulator inlet; 14. Second regulator inlet; 15. First control element; 16. First metering pump; 17. Second control element ; 18. The first pH monitoring element; 21. The aerator;

31. Coagulant inlet; 32. First coagulation inlet; 33. Second coagulation inlet; 34. Third controller; 35. Second metering pump; 36. Mixing equipment; 37. Coagulation tank water inlet; 38. The fourth controller; 39. The third metering pump;

61. Acid dosing port; 62. The fifth metering pump; 63. The third pH monitoring element; 64. The sixth controller;

01. The first conditioner input pipeline; 02. The second conditioner input pipeline; 03. The coagulant input pipeline; 04. The water inlet pipeline of the coagulation tank; 05. The neutralization water output pipeline; 06. The acid input pipeline; industrial style.

Detailed ways

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below in conjunction with examples.

As mentioned in the background technology, the treatment method of high ammonia nitrogen and high hardness wastewater in the prior art has a low effect on the removal of total hardness, and has a greater impact on subsequent biochemical treatment and scaling of underwater equipment. In order to improve this situation, in In a typical implementation of the present application, a high ammonia nitrogen high hardness wastewater pretreatment device is provided, as shown in Figure 1, the pretreatment device includes: a buffer stripping tank 10, an aeration device 20 and a coagulation tank 30 The buffer blowing tank 10 has an alkaline conditioner inlet, a waste water inlet 11 and a buffer blowing tank outlet 12; the aeration device 20 is arranged at the bottom of the buffer blowing tank 10; the coagulation tank 30 includes a coagulant inlet 31, a mixing tank The water inlet 37 of the coagulation tank and the water outlet of the coagulation tank; wherein, the water outlet 12 of the buffer blowing tank is connected with the water inlet 37 of the coagulation tank.

The high ammonia nitrogen high hardness wastewater pretreatment device provided by the application, by setting the aeration device 20 at the bottom of the buffer blowing tank 10, the alkaline conditioner added from the alkaline conditioner inlet and the high ammonia nitrogen high hardness wastewater are fully Mixed reaction, part of the calcium and magnesium ions in the wastewater are converted into precipitates by the alkaline regulator for removal, in addition, part of the ammonia gas overflows out of the water body, so that the total hardness removal rate in the wastewater is higher, and the ammonia nitrogen can also be removed Preliminary removal; then the wastewater discharged from the outlet 12 of the buffer blowing tank is further coagulated and precipitated through the coagulation tank 30, so that the turbidity of the wastewater discharged from the outlet of the coagulation tank is further reduced. The device is used for pretreatment of high ammonia nitrogen and high hardness wastewater, and the total hardness removal efficiency is high, which greatly reduces the impact on subsequent biochemical treatment and underwater equipment scaling.

As shown in Figure 2, the above-mentioned aeration equipment 20 can be an aeration tube arranged in a matrix at the bottom of the buffer blowing tank 10 (the gas can come from industrial wind A), and the alkaline conditioner is fully mixed with the high ammonia nitrogen high hardness wastewater After the reaction, a part of ammonia gas is produced, which can spill out of the water body after being blown by the aerator 21 on the aeration pipe.

According to the different types of alkaline regulators, the above-mentioned alkaline regulator inlets should be reasonably set in the form and number of inlets. In a preferred embodiment of the present application, as shown in Figure 2, the above-mentioned alkaline conditioner inlet includes: a first conditioner inlet 13 and a second conditioner inlet 14, the first conditioner inlet 13 and the first conditioner inlet The input line 01 communicates; the second conditioner inlet 14 communicates with the second conditioner input line 02 . In some preferred embodiments, along the input direction of the first regulator, a first control element 15 and a first metering pump 16 are sequentially arranged on the first regulator input line 01 . In some preferred embodiments, along the input direction of the second regulator, the second regulator input line 02 is provided with a second control element 17 and a first pH monitoring element 18 in sequence.

When the above-mentioned device is added with an alkaline regulator, there are generally two alkaline regulators (one is sodium hydroxide and the other is sodium carbonate), which are used to precipitate calcium and magnesium ions in the wastewater, thereby reducing the waste water. hardness. The two regulators are added separately through the first conditioner input pipeline 01 and the second conditioner input pipeline 02, which facilitates flexible adjustment of the addition amount of different alkaline conditioners according to different conditions of different wastewater. Further, control elements and metering pumps or pH monitoring elements are set on the input pipelines of each regulator, so as to automatically adjust the dosage of different alkaline regulators according to various indicators in the waste water and incoming water.

As shown in Figure 3, in a preferred embodiment, the coagulant inlet 31 and the coagulant input line 03; preferably, the coagulant input line 03 is provided with a first coagulation inlet 32 and a second Coagulation inlet 33; preferably, a third controller 34 and a second metering pump 35 are also provided on the coagulant input line 03, the third controller 34 and the second metering pump 35 are used to control and meter the first mixed The dosage of the coagulation inlet 32 and the second coagulation inlet 33; preferably, a mixing device 36 is also provided on the coagulant input line 03, along the flow direction of the coagulant, the first coagulation inlet 32 and the second coagulation inlet 32 The inlet 33 communicates with the coagulant inlet 31 by mixing.

In order to add the amount of coagulant relatively more accurately, the above-mentioned preferred embodiment is convenient to accurately add the coagulant according to the amount of water in the coagulation tank 30 by setting the coagulant input pipeline 03 and a controller and a metering pump on the pipeline. The amount of coagulant. And after the coagulant and its additives are added, it is further mixed and then input into the coagulation tank 30, so that the aggregation and sedimentation effect of the coagulant can be exerted as soon as it is added into the coagulation tank 30, and the coagulation efficiency is improved. The above-mentioned mixing equipment 36 can be existing, for example, a static mixer can be used.

In some preferred embodiments, as shown in Figure 3, the coagulation tank water inlet 37 communicates with the coagulation tank water inlet pipeline 04, and the coagulation tank water inlet pipeline 04 is provided with a fourth controller 38 and a third controller in sequence along the water flow direction. Metering pump 39, the water inflow signal measured by the third metering pump 39 is transmitted to the fourth controller 38, and the fourth controller 38 is electrically connected to the third controller 34 (not shown) and the third metering pump 39 is metered. The water inflow signal is converted into an electrical signal and transmitted to the third controller 34 , and the third controller 34 adjusts the dosing value of the second metering pump 35 through the electrical signal.

In the above-mentioned preferred embodiment, by setting a controller and a metering pump on the water inlet line 04 of the coagulation tank, and connecting them with the controller on the coagulant input line 03 for electrical signals, the coagulation tank 30 can The flow rate is automatically interlocked to control the pump dosage of the coagulant.

In some preferred embodiments, as shown in FIG. 1 , the pretreatment device further includes a sludge mixing tank 40 , and the sludge mixing tank 40 is arranged between the buffer stripping tank 10 and the coagulation tank 30 along the water flow direction. In some preferred embodiments, the sludge mixing tank 40 is provided with a sludge return port. In some preferred embodiments, the sludge return port communicates with the sludge return line, and the sludge return line is provided with a fifth controller and a fourth metering pump connected in sequence.

The buffer blowing tank water outlet of the above buffer blowing tank 10 is connected with the water inlet of the sludge mixing tank 40, and the waste water inlet 11 of the buffer blowing tank is provided with a lift pump (equipped with a flow meter), and the lift pump For frequency conversion control. The flow shown by the inflow of the buffer stripping tank 10 is the overall load of the pretreatment device, and the overall load is fed back to the fifth controller, and the fifth controller is used to regulate the amount of sludge return to add In the case of maintaining the normal operation of the pretreatment device, the repurification treatment of the return sludge is realized. According to the actual operation experience of the present application, the pumping volume of the fourth metering pump is preferably 0.6-1% of the water intake of the buffer blowing tank 10, so as to realize the recycling of the return sludge while maintaining the normal operation of the pretreatment device. Purification treatment.

In order to further improve the degree of purification of the wastewater treated by the pretreatment device, in some preferred embodiments, as shown in Figure 1, the pretreatment device also includes a sedimentation tank 50, the sedimentation tank 50 communicates with the coagulation tank 30, and along the water flow The direction is set downstream of the coagulation tank 30 . The effluent from the coagulation tank 30 enters the sedimentation tank 50 to realize mud-water separation and increase the mud content in the treated wastewater.

In order to further make the effluent of the sedimentation tank meet the requirements of the subsequent treatment process, in some preferred embodiments, the sedimentation tank includes an outlet pipeline, and a second pH monitoring element is arranged on the outlet pipeline. In some preferred embodiments, the second pH monitoring element is electrically connected with the first control element 15 and the second control element 17, and the pH value monitored by the second pH monitoring element is fed back to the first control element 15 and the second control element 15. The control element 17 is used to control the addition amount of the conditioner in the first conditioner inlet 13 and the second conditioner inlet 14 .

By setting the pH monitoring element on the outlet water pipeline of the sedimentation tank, the pH of the outlet water is controlled between 10.2 and 10.5. When pH<10.2, the second pH monitoring element is electrically connected with the first control element 15 and the second control element 17, and the pH value monitored by the second pH monitoring element is fed back to the first control element 15 and the second control element 17, so as to increase the frequency of the lye dosing pump; and when the online pH>10.5, reduce the frequency of the lye dosing pump; when the online pH is between 10.2 and 10.5, the frequency of the lye dosing pump remains unchanged.

In some preferred embodiments, the sedimentation tank includes a water outlet line, a hardness meter is arranged on the water outlet line, the hardness meter is electrically connected with the first control element 15 and the second control element 17, and the hardness value monitored by the hardness meter is fed back to The first control element 15 and the second control element 17 control the addition amount of the regulator at the first regulator inlet 13 and the second regulator inlet 14 .

By setting a hardness meter on the outlet pipeline of the sedimentation tank and electrically connecting the hardness meter with the first control element 15 and the second control element 17, it is convenient for the hardness meter to feed back the monitored hardness value to the first control element 15 and the second control element 17. The control element 17 is used to control the addition amount of the regulator at the first conditioner inlet 13 and the second conditioner inlet 14, that is, to realize the interlock between the hardness control and the lye dosing pump, and to realize automatic dosing.

The above-mentioned second pH monitoring element and the hardness meter are usually selected for interlocking control, and the hardness meter is generally interlocked for self-control, while the pH may not be interlocked with the hardness meter, and online auxiliary monitoring is possible.

In order to further make the pretreated water further meet subsequent process requirements, in some preferred embodiments, as shown in Figure 4, the pretreatment device also includes: a neutralization tank 60, and the neutralization tank 60 includes an acid dosing port 61 and Neutralized water output line 05. In some preferred embodiments, the acid feeding port 61 communicates with the acid input line 06 , and the acid input line 06 is also provided with a sixth controller 64 and a fifth metering pump 62 . In some preferred embodiments, a third pH monitoring element 63 is provided on the neutralization water output pipeline 05 , and the third pH monitoring element 63 is electrically connected to the fifth metering pump 62 through a sixth controller 64 .

In the preferred embodiment above, the pH monitoring element set on the neutralization water output pipeline realizes the interlocking control with the controller set on the acid input pipeline and the acid metering pump, and realizes the automatic appropriate dosage of the acid pump. Specifically, when the online monitoring pH<8, reduce the (sulfur) acid pump feeding frequency; when the online monitoring pH>8.5, increase the (sulfur) acid feeding pump frequency; when the online monitoring pH<8～ 8.5, the (sulfur) acid pump frequency remains unchanged.

The qualified water after the above pretreatment can enter the subsequent biochemical A/O process for denitrification treatment. Therefore, in the second typical implementation of the present application, a high ammonia nitrogen high hardness wastewater treatment system is provided, the system includes: a pretreatment device and a biochemical device, the pretreatment device is any one of the above high ammonia nitrogen high hardness Wastewater pretreatment device; the biochemical device is arranged downstream of the pretreatment device.

The high ammonia nitrogen high hardness wastewater treatment system has a high total hardness removal rate in the pretreatment device, which greatly reduces the impact on subsequent biochemical treatment and underwater equipment scaling. At the same time, the preliminary removal of ammonia nitrogen was carried out, which will help to further improve the removal efficiency of ammonia nitrogen.

In the third typical embodiment of the present application, a pretreatment method for high ammonia nitrogen and high hardness wastewater is provided, the pretreatment method includes: adding an alkaline regulator to the high ammonia nitrogen and high hardness wastewater to form the first mixed wastewater; Aeration treatment is performed on the first mixed wastewater to obtain the first dehardness and ammonia nitrogen removal wastewater; coagulation treatment is performed on the first dehardness and ammonia nitrogen removal wastewater to obtain coagulation treated wastewater.

In the above pretreatment method, aeration treatment is performed after adding an alkaline regulator to the high ammonia nitrogen and high hardness wastewater, so that the alkaline regulator and the high ammonia nitrogen and high hardness wastewater are fully mixed and reacted, and part of the calcium and magnesium ions in the wastewater are absorbed by the alkali In addition, part of the generated ammonia gas overflows out of the water body, so that the total hardness removal rate in the wastewater is higher, and the ammonia nitrogen can also be initially removed; and then the coagulation treatment is further reduced. Treat the turbidity of wastewater. The method has high total hardness removal efficiency for high ammonia nitrogen and high hardness wastewater, and greatly reduces the impact on subsequent biochemical treatment and underwater equipment scaling.

The amount and type of the above-mentioned alkaline regulators can be reasonably selected and adjusted according to actual needs. In some preferred embodiments, the alkaline conditioner includes sodium hydroxide and sodium carbonate; preferably, the dosage of sodium hydroxide is preferably 2000-3000ppm, more preferably 2200-2500ppm; preferably, the dosage of sodium carbonate The dosage is 120-250 ppm, more preferably 150-200 ppm; preferably, the aeration treatment time is 1.5-5 hours, preferably 2-3 hours.

According to the different indicators of different batches of high ammonia nitrogen and high hardness wastewater, it can be adjusted. And the dosage of above-mentioned sodium hydroxide and sodium carbonate is the preferred dosage obtained according to countless batches of this type of wastewater treatment, the dosage is within the above-mentioned range, and the time of aeration treatment is within the above-mentioned preferred range Within, the total hardness removal rate can reach 43-61%, and the ammonia nitrogen removal rate can reach 15-20%.

The above-mentioned coagulation treatment varies according to the type of coagulant and its auxiliaries used. In some preferred embodiments, a coagulant is added to the first dehardened and deammoniated nitrogen wastewater for coagulation treatment to obtain coagulation treatment wastewater; wherein the coagulant includes PAC and PAM; preferably, the dosage of PAC 20-40ppm, more preferably 25-35ppm; preferably, the dosage of PAM is 0.2-0.8ppm, more preferably 0.4-0.6ppm. Under the above preferred conditions, the turbidity of coagulation wastewater can be greatly reduced.

In some preferred embodiments, before performing coagulation treatment on the first dehardened and deammonized nitrogen wastewater, the pretreatment method further includes: a step of mixing sludge into the first dehardened and deammonized nitrogen wastewater. This step (1) is to provide crystal nuclei for the adhesion of calcium and magnesium carbonate, reduce the scaling probability of the pool wall, and at the same time, there are sludge mixed particles, forming calcium hard and loose, easy to remove. (2) It can effectively increase the use effect of subsequent flocculants and coagulation aids, reduce the dosage of chemicals, and improve the settlement effect.

In order to be more conducive to the subsequent treatment, in some preferred embodiments, after obtaining the coagulation wastewater, the pretreatment method also includes: performing sedimentation treatment on the coagulation wastewater to separate the mud and water to obtain the deslimed wastewater; preferably, after obtaining the deslimed wastewater After the muddy wastewater, the pretreatment method also includes: adjusting the pH value of the deslimed wastewater to obtain the first step of adjusting the wastewater; more preferably, adjusting the amount of sodium hydroxide added to the wastewater with high ammonia nitrogen and high hardness to adjust the deslimed wastewater. The pH value of the sludge wastewater is further preferably adjusted to a pH value of 10.2 to 10.5 for the deslimed wastewater.

The desliming treatment reduces the mud content in the subsequent wastewater, which is conducive to the effective removal of organic components such as ammonia nitrogen in the wastewater. The best use of polyaluminum chloride is at a pH of 7.5 to 8.5, and the adjustment of the pH value of the effluent after desliming can ensure the best dosing effect of the coagulation reaction.

In some preferred embodiments, after obtaining the first adjusted wastewater, the pretreatment method further includes: neutralizing the first adjusted wastewater to obtain neutralized wastewater; preferably, the pH value of the neutralized wastewater is 6-9 , more preferably the pH value is 8-8.5; preferably, the neutralization treatment is performed by adding an acid solution to the first adjusted wastewater, and more preferably, the acid solution is sulfuric acid. The above neutralization step is to control the pH value of the effluent to meet the technological requirements of the subsequent biochemical treatment.

The beneficial effects of the present application will be further described below in conjunction with specific embodiments.

For the above wastewater, the following embodiments utilize the device shown in FIG. 1 to perform pretreatment according to the process shown in FIG. 2 . Among them, DCS in Figure 1 is a distributed control system, and FIQ: flow meter. See Table 1 for the processing results.

Table 1:

Attachment: The above lye is sodium hydroxide.

From the above description, it can be seen that the above-mentioned embodiments of the present invention have achieved the following technical effects: (1) by increasing the aeration treatment in the buffer adjustment step, the total hard removal rate has been improved; Dosage, so that the total hard removal rate can reach 38% ~ 61%; (2) increase the removal rate of ammonia nitrogen, it can reach 12% ~ 20%; (3) the turbidity of the effluent can reach 5 ~ 10NTU, so that the effluent can meet Water intake requirements for biochemical systems; (4) The system realizes fully automatic control operation.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (16)

1. a kind of high ammonia nitrogen and high hardness sewage pretreatment device, which is characterized in that the pretreatment unit includes:

It buffers stripping pond (10), there is the buffering stripping pond (10) alkaline conditioner entrance, waterwater entrance (11) and buffering to blow De- pond water outlet (12)；

Aerator (20), the aerator (20) are arranged in buffering stripping pond (10) bottom；

Coagulating basin (30), the coagulating basin (30) include coagulant entrance (31), coagulating basin water inlet (37) and coagulating basin water outlet Mouthful；

Wherein, the buffering stripping pond water outlet (12) is connected with the coagulating basin water inlet (37).

2. pretreatment unit according to claim 1, which is characterized in that the alkaline conditioner entrance includes:

First regulator entrance (13), the first regulator entrance (13) and the first regulator intake pipeline (01) are even It is logical；

Second regulator entrance (14), the second regulator entrance (14) and the second regulator intake pipeline (02) are even It is logical；

Preferably, first is disposed with along the input direction of the first regulator, the first regulator intake pipeline (01) Control element (15) and the first metering pump (16)；

Preferably, second is disposed with along the input direction of the second regulator, the second regulator intake pipeline (02) Control element (17) and the first pH monitoring element (18).

3. pretreatment unit according to claim 1, which is characterized in that the coagulant entrance (31) and coagulant input Pipeline (03) connection；

Preferably, the first coagulation entrance (32) and the second coagulation entrance have been arranged in parallel on the coagulant intake pipeline (03) (33)；

Preferably, third controller (34) and the second metering pump (35), institute are additionally provided on the coagulant intake pipeline (03) It states third controller (34) and the second metering pump (35) is respectively used to control and measure the first coagulation entrance (32) and second The dosage of coagulation entrance (33)；

Preferably, it is additionally provided with mixing apparatus (36) on the coagulant intake pipeline (03), it is described along coagulant flow direction First coagulation entrance (32) and the second coagulation entrance (33) pass through the mixing apparatus (36) and the coagulant entrance (31) it is connected to.

4. pretreatment unit according to claim 3, which is characterized in that the coagulating basin water inlet (37) enters with coagulating basin Water pipeline (04) connection is disposed with the 4th controller (38) and the along water (flow) direction on the coagulating basin water inlet pipe line (04) The water signal that enters of three metering pumps (39), third metering pump (39) metering is transferred to the 4th controller (38), described 4th controller (38) passes through with the third controller (34) to be electrically connected and the third metering pump (39) metering is entered water Amount signal is converted into electric signal and is transferred to the third controller (34), and the third controller (34) passes through the electric signal tune That saves second metering pump (35) adds value.

5. pretreatment unit according to claim 2, which is characterized in that the pretreatment unit further includes sludge mixing pit (40), along water (flow) direction, sludge mixing pit (40) setting the buffering stripping pond (10) and the coagulating basin (30) it Between；

Preferably, sludge reflux mouth is provided on the sludge mixing pit (40)；

Preferably, the sludge reflux mouth is connected to sludge reflux pipeline, is provided with and is sequentially communicated on the sludge reflux pipeline The 5th controller and the 4th metering pump.

6. pretreatment unit according to claim 5, which is characterized in that the pretreatment unit further includes sedimentation basin (50), the sedimentation basin (50) is connected to the coagulating basin (30), and is arranged under the coagulating basin (30) along water (flow) direction Trip.

7. pretreatment unit according to claim 6, which is characterized in that the sedimentation basin (50) includes water outlet pipeline, institute It states and is provided with the 2nd pH monitoring element on water outlet pipeline；

Preferably, the 2nd pH monitoring element is electrically connected with first control element (15) and second control element (17) It connects, and the pH value that the 2nd pH monitoring element monitors is fed back into first control element (15) and second control Element (17), to control the addition of the regulator of the first regulator entrance (13) and the second regulator entrance (14) Amount.

8. pretreatment unit according to claim 6, which is characterized in that the sedimentation basin (50) includes water outlet pipeline, institute It states and is provided with hardness instrument, the hardness instrument and first control element (15) and the second control member on water outlet pipeline Part (17) electrical connection, and the hardness number that the hardness instrument monitors is fed back into first control element (15) and described the Two control elements (17), to control the regulator of the first regulator entrance (13) and the second regulator entrance (14) Additive amount.

9. pretreatment unit according to claim 7, which is characterized in that the pretreatment unit further include: neutralization pond (60), the neutralization pond (60) includes that acid adds mouth (61) and neutralizes water delivery pipe line (05),

Preferably, the acid adds mouth (61) and is connected to sour intake pipeline (06), is additionally provided on the acid intake pipeline (06) 5th metering pump (62)；

Preferably, the 3rd pH monitoring element (63), the 3rd pH monitoring member are provided on the neutralization water delivery pipe line (05) Part (63) and the 5th metering pump (62) are electrically connected with the 6th controller (64).

10. a kind of high ammonia nitrogen and high hardness waste water treatment system, which is characterized in that the system comprises:

Pretreatment unit, the pretreatment unit high ammonia nitrogen and high hardness waste water as claimed in any one of claims 1 to 9 are located in advance Manage device；And

The downstream of the pretreatment unit is arranged in biochemical device, the biochemical device.

11. a kind of high ammonia nitrogen and high hardness pretreatment method for wastewater, which is characterized in that the preprocess method includes:

Alkaline conditioner is added into high ammonia nitrogen and high hardness waste water, forms the first composite waste；

Air Exposure is carried out to first composite waste, obtains the first hard-off ammonia nitrogen removal waste water；

Coagulating treatment is carried out to the first hard-off ammonia nitrogen removal waste water, obtains coagulating treatment waste water.

12. preprocess method according to claim 11, which is characterized in that the alkaline conditioner include sodium hydroxide and Sodium carbonate；

Preferably, the dosage of the preferably described sodium hydroxide is 1800~3000ppm, more preferably 2200~2500ppm；

Preferably, the dosage of the preferably described sodium carbonate is 100~250ppm, more preferably 150~200ppm；

Preferably, the time of the Air Exposure is 1.5~5 hours, preferably 2~3 hours.

13. preprocess method according to claim 12, which is characterized in that

Coagulant is added into the first hard-off ammonia nitrogen removal waste water and carries out the coagulating treatment, and it is useless to obtain the coagulating treatment Water；Wherein, the coagulant includes PAC and PAM；

Preferably, the dosage of the PAC is 20~40ppm, more preferably 25~35ppm；

Preferably, the dosage of the PAM is 0.2~0.8ppm, more preferably 0.4~0.6ppm.

14. preprocess method according to claim 13, which is characterized in that mixed to the first hard-off ammonia nitrogen removal waste water Before solidifying processing, the preprocess method further include: in Xiang Suoshu the first hard-off ammonia nitrogen removal waste water the step of mixing sludge.

15. preprocess method according to claim 13, which is characterized in that described after obtaining the coagulation waste water Preprocess method further include:

Carrying out precipitation process to the coagulation waste water makes mud-water separation, obtains deslimed wastewater；

Preferably, after obtaining the deslimed wastewater, the preprocess method further include: pH value is carried out to the deslimed wastewater The step of being adjusted, obtaining the first adjusting waste water；

It is highly preferred that being adjusted by the amount for adjusting the sodium hydroxide being added in the high ammonia nitrogen and high hardness waste water described de- The pH value of mud waste water, the pH value for further preferably adjusting the deslimed wastewater is 10.2~10.5.

16. preprocess method according to claim 15, which is characterized in that after obtaining the first adjusting waste water, The preprocess method further include: the first adjusting waste water is neutralized, obtains neutralizing waste water；

Preferably, the pH value for neutralizing waste water is 6~9, and more preferable pH value is 8~8.5；

Preferably, the neutralisation treatment is carried out by adding acid solution into the first adjusting waste water, it is highly preferred that the acid Liquid is sulfuric acid.