CN105366749A - Treatment method of high-salinity organic volatile waste water - Google Patents

Abstract

The invention discloses a treatment method for high-salt organic volatile wastewater. The specific steps are: (1) take high-salt organic volatile wastewater and add it to an evaporation device, then add persulfate solution and stir and mix evenly; (2) Adjust the pH of the mixed solution in the evaporator to 6-9, heat and evaporate the wastewater in the evaporator at a rate of 3.5°C/min, and the steam generated during the evaporation process enters the next condensing device; (3) Condensed in the condensing device The resulting condensed water enters the drainage system with the drain pipe, and the concentration of organic matter in the condensed water meets the discharge standard; (4) After the waste water in the evaporating device is completely evaporated, the residual salt in the evaporating device is taken out for recovery, and the recovered salt nearly anhydrous. The invention simultaneously realizes the recovery of salt in high-salt organic wastewater and the degradation of organic pollutants in a simple and effective manner.

Description

A treatment method for high-salt organic volatile wastewater

technical field

The invention belongs to the technical field of industrial wastewater treatment, and in particular relates to a treatment method for high-salt organic volatile wastewater.

Background technique

During the synthesis of intermediates in food processing and fine chemicals, pharmaceuticals, pesticides, dyes and other industries, high-salt organic wastewater will be produced. Due to the high salt content in these high-salt organic wastewater, which has a strong killing and inhibiting effect on microorganisms, traditional biochemical methods cannot be used for treatment. Usually, evaporation and crystallization technology must be used for desalination first, and then biochemical or other methods The further treatment of condensed sewage is complex and difficult to operate and manage. Therefore, the development of a new high-salt wastewater treatment process to achieve both salt recovery and organic pollutant degradation in one treatment unit is a breakthrough in the field of high-salt organic wastewater treatment and has broad application prospects.

Contents of the invention

The technical problem solved by the present invention is to provide a treatment method for high-salt organic volatile wastewater that realizes salt recovery and organic pollutant degradation in high-salt organic wastewater in a simple and effective manner. The treatment method has low investment and high treatment efficiency. The treatment process is short and the operation difficulty is small. By controlling the heating rate, the volatile organic pollutants in the wastewater can be quickly degraded, so that the organic substances in the wastewater will not volatilize with the steam, and ensure that the concentration of organic substances in the condensed water meets the discharge standards. There are basically no organic pollutants left in the evaporation device, and the recovered salt has a low organic content and high usable value. This process can be used to effectively treat high-salt organic wastewater without large-scale transformation of the existing evaporation device of the enterprise.

The present invention adopts following technical scheme for solving above-mentioned technical problem, a kind of treatment method of high-salt organic volatile waste water, it is characterized in that concrete steps are:

(1) Take high-salt organic volatile wastewater and add it to the evaporation device, then add persulfate solution and stir to mix evenly;

(2) Adjust the pH of the mixed solution in the evaporation device to 6-9, heat and evaporate the wastewater in the evaporation device at a heating rate of 3.5°C/min, and the steam generated during the evaporation process enters the next condensation device;

(3) The condensed water produced after condensation in the condensing device enters the drainage system along with the drain pipe, and the concentration of organic matter in the condensed water meets the discharge standard;

(4) After the waste water in the evaporator is completely evaporated, the salt remaining in the evaporator is taken out for recovery, and the recovered salt is close to anhydrous state.

The treatment method of methanol high-salt organic wastewater of the present invention is characterized in that the specific steps are:

(1) Take 50mL of methanol high-salt organic wastewater with a methanol mass concentration of 500mg/L and a NaCl mass fraction of 5% into the evaporation device, then add a potassium persulfate solution containing 5.4064g of potassium persulfate and stir to mix evenly;

(2) Adjust the pH of the mixed solution in the evaporating device to 7, heat and evaporate the wastewater in the evaporating device at a heating rate of 3.5°C/min, and the steam generated during the evaporation process enters the next condensing device;

(3) The condensed water produced after condensing in the condensing device enters the drainage system along with the drain pipe, and the concentration of methanol in the condensed water meets the discharge standard;

(4) After the waste water in the evaporator is completely evaporated, the salt remaining in the evaporator is taken out for recovery, and the recovered salt is close to anhydrous state.

Compared with the prior art, the present invention has the following beneficial effects:

1. It can effectively degrade organic pollutants in high-salt organic wastewater without secondary treatment of condensed water;

2. Salt substances in high-salt organic wastewater can be recovered;

3. The evaporation device can be used to realize the degradation of organic matter and the recovery of salt substances at the same time. The whole sewage treatment process can be completed in one step in one evaporation device. The treatment process is short, the treatment device is simple, and the treatment efficiency is high.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Fig. 2 is the degradation curve of the embodiment of the present invention 2 different concentrations of potassium persulfate solutions to methanol high-salt wastewater;

Fig. 3 is the degradation curve of the mixed solution of embodiment 3 of the present invention different pH to methanol high-salt wastewater;

Fig. 4 is the degradation curve of NaCl with different mass fractions of the embodiment of the present invention 4 to methanol high-salt wastewater;

Fig. 5 is the degradation curve of methanol high-salt wastewater with different dosing methods of persulfate in Example 5 of the present invention.

detailed description

The above-mentioned contents of the present invention are described in further detail below through the embodiments, but this should not be interpreted as the scope of the above-mentioned themes of the present invention being limited to the following embodiments, and all technologies realized based on the above-mentioned contents of the present invention all belong to the scope of the present invention.

Example 1

The mass fraction of NaCl in the wastewater was 5%, and the pH of the system was pre-adjusted to 7. Table 1 shows the complete degradation of high-salt wastewater with different concentrations of methanol. It can be seen that the amount of persulfate required for nearly complete degradation of COD in high-salt organic wastewater containing different concentrations of methanol is in a certain linear proportional relationship.

Table 1 Complete degradation of high-salt wastewater with different concentrations of methanol

Methanol concentration (mg/L) Potassium persulfate concentration (moL/L) COD degradation rate (%) 1000 0.1 98.3 900 0.09 98.2 800 0.08 98.7 700 0.07 98.4 600 0.06 98 500 0.05 96.9

Example 2

The concentration of methanol in the wastewater is 500mg/L, the mass fraction of NaCl is 5%, the pH of the system is adjusted to 7, and the heating rate of the evaporation device is controlled to be 3.5°C/min. Figure 2 is the impact of potassium persulfate concentration on the degradation of methanol high-salt wastewater. As can be seen from Figure 2, along with the continuous increase of potassium persulfate concentration, the COD of the distillate is constantly decreasing. When the concentration of potassium persulfate is 0.05moL/ L, the COD of the distillate is almost completely degraded, which means that the organic matter in the wastewater solution is almost completely degraded during the heating and evaporation process.

Example 3

The concentration of methanol in the wastewater is 500mg/L, the mass fraction of NaCl is 5%, the concentration of potassium persulfate is 0.04mol/L, and the heating rate of the evaporation device is controlled to be 3.5°C/min. Figure 3 shows the effect of pH on the degradation of methanol high-salt wastewater. It can be seen from Figure 3 that pH has little effect on it. When the pH in the reaction system is 7, it is more conducive to the reaction than the acidic and alkaline environment.

Example 4

The concentration of methanol in the wastewater is 500mg/L, the concentration of potassium persulfate is 0.04moL/L, the pH of the system is adjusted to 7, and the heating rate of the evaporation device is controlled to be 3.5°C/min. Figure 4 shows the effect of NaCl on the degradation of high-salt methanol wastewater. As can be seen from Figure 4, the mass fraction of NaCl increased from 1% to 3%, which slightly inhibited the degradation of high-salt methanol wastewater. In general, NaCl has little effect on the degradation of methanol high-salt wastewater.

Example 5

The concentration of methanol in the wastewater is 500mg/L, the concentration of potassium persulfate is 0.04moL/L, the mass fraction of NaCl is 5%, the pH of the system is adjusted to 7, and the heating rate of the evaporation device is controlled to 3.5°C/min. Figure 5 shows the effect of potassium persulfate dosing methods on the degradation of methanol high-salt wastewater. Dosing method 1: the dosage of potassium persulfate is 5.4064g, and it is dissolved; Dosing method 2: adding potassium persulfate particles 5.4064g g; Dosing method 3: 3.379g+0.6758g+0.6758g+0.6758g; Dosing method 4: 2.7032g+1.3516g+0.6758g+0.6758g; Dosing method 5: 1.3516g+1.3516g+1.3516g+1.3516g, the dosing time interval is 30min , as can be seen from Figure 5, dosing mode 1 is the best.

The above embodiments have described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What are described in the above embodiments and description are only to illustrate the principles of the present invention. Without departing from the scope of the principle of the present invention, there will be various changes and improvements in the present invention, and these changes and improvements all fall within the protection scope of the present invention.

Claims (2)

1. a treatment process for high salt volatile organic waste water, is characterized in that concrete steps are:

(1) get high salt volatile organic waste water to join in evaporation unit, then add persulfate solution and be uniformly mixed;

(2) regulate the pH=6-9 of mixing solutions in evaporation unit, to the waste water in evaporation unit with the temperature rise rate heating evaporation of 3.5 DEG C/min, the steam that evaporative process produces enters next condensing works;

(3) water of condensation produced after condensation in condensing works enters in water exhaust system with water shoot, and in this water of condensation, organic concentration meets emission standard;

(4), after the complete evaporate to dryness of waste water in device to be evaporated, take out salinity residual in evaporation unit and reclaim, the salinity of recovery is close to anhydrous state.

2. a treatment process for methyl alcohol height salt organic waste water, is characterized in that concrete steps are:

(1) to get 50mL methanol quality concentration be 500mg/L, NaCl massfraction be 5% methyl alcohol height salt organic waste water join in evaporation unit, then the potassium persulfate solution added containing 5.4064g Potassium Persulphate being uniformly mixed;

(2) regulate the pH=7 of mixing solutions in evaporation unit, to the waste water in evaporation unit with the temperature rise rate heating evaporation of 3.5 DEG C/min, the steam that evaporative process produces enters next condensing works;

(3) water of condensation produced after condensation in condensing works enters in water exhaust system with water shoot, and in this water of condensation, the concentration of methyl alcohol meets emission standard;

(4), after the complete evaporate to dryness of waste water in device to be evaporated, take out salinity residual in evaporation unit and reclaim, the salinity of recovery is close to anhydrous state.