Disclosure of Invention
The invention aims to provide a method for treating ginseng filtrate wastewater, which aims to solve the problems in the background technology.
In order to solve the technical problems, the invention provides the following technical scheme: a method for treating ginseng filtrate wastewater comprises the following steps:
iron-carbon microelectrolysis: adjusting the pH value of the ginseng filtrate wastewater to be acidic, and carrying out iron-carbon micro-electrolysis reaction to obtain a treatment solution I;
fenton oxidation: adding 1-3% of 30% hydrogen peroxide by mass into the treatment liquid I, and oxidizing for 1h at the water temperature of 20-30 ℃ to obtain a treatment liquid II;
flocculation and precipitation: adding caustic soda flakes into the treatment liquid II to adjust the pH value to 8-9; adding 0.01 mass percent of PAM, quickly stirring for 0.1-0.5 min, uniformly mixing, and filtering to obtain a filtrate III;
and (3) adsorption and decoloration: adding an adsorbent into the filtrate III, and filtering to obtain a filtrate IV;
biochemical treatment: and (4) discharging the filtrate IV after the filtrate IV enters a biochemical pool to stay.
Preferably, dilute waste acid is used for adjusting the pH value of the wastewater to be 3.0-5.0 in the iron-carbon micro-electrolysis reaction; the reagents added in the iron-carbon reaction comprise 60-80 meshes of iron powder and carbon powder, the adding amount of the iron powder is 1.5-2.5% of the mass of the wastewater, the volume ratio of the iron powder to the carbon powder is 1: 1-1.5, and the reaction time is 3.0-4.0 h, so that the treatment solution I is obtained.
Preferably, in the step of flocculation precipitation, after the medicament is put into the flocculation precipitation, the rapid stirring speed is 120-180 r/min; then slowly stirring for 10-20 sedimentation, wherein the slow stirring speed is 15-40 r/min.
Preferably, in the flocculation precipitation step, a coagulant is added at intervals of PAM, and the coagulant is one of polymeric ferric sulfate, polymeric ferric chloride, polymeric aluminum sulfate and polymeric aluminum chloride.
Preferably, the device comprises a filter tower, wherein the filter tower is used for adsorbing the filtrate III;
a filter bin is arranged in the filter tower, the filter bin is filled with adsorption particles, a driving box is arranged at the bottom of the filter bin, and a driving mechanism in the driving box drives the filter bin to rotate around the center of the filter bin;
two input ports are arranged at the top of the filtering tower, filtrate III is obliquely sprayed out of the first input port, adsorption particles are obliquely sprayed out of the second input port, the spraying directions of the filtrate III and the adsorption particles are intersected, so that the filtrate III and the adsorption particles are mixed in the air and finally enter the filtering bin, the adsorption particles are retained and stored by the adsorption bin, and the filtrate III is filtered out of the adsorption bin.
Preferably, a main gear is installed in the driving box, a rack is arranged on the inner wall of the filter tower, the main gear is fixedly installed on the rack, the bottom of the bin wall of the filter bin is connected with an underframe, a planet gear is installed on the underframe, the planet gear is meshed with the main gear, is driven by a motor and rotates around the main gear, and therefore the filter bin is driven to rotate around the center of the main gear;
a transition wheel is arranged on one side of the planet wheel, the transition wheel is rotatably connected to the bottom frame and meshed with the planet wheel, the transition wheel is hinged with a connecting rod, and the end part of the connecting rod is hinged with a discharge plate;
the bottom of the filter bin is provided with a discharge bin which is of a fixed structure and does not rotate along with the filter bin, the discharge bin is communicated with the filter bin through an upper opening, and the two side openings of the discharge bin drop on adsorption particles in the discharge bin, are pushed out of the discharge bin by a discharge plate and enter a recovery bin arranged on the wall of the filter tower.
Preferably, the discharge bin is positioned in the filter bin and is rotationally connected with the filter bin, the bottom of the discharge bin is provided with a discharge groove, the discharge plate is slidably connected in the discharge groove, and the adsorption particles at the bottommost part are gathered in the discharge groove and are discharged out of the tower along with the sliding of the discharge plate;
the bottom side wall of the filter bin is provided with a notch, the side wall of the filter tower is symmetrically provided with two through grooves, and the two through grooves are communicated with the recovery bin.
Preferably, an elution bin is arranged at the top of the filter tower, eluent is contained in the elution bin, a channel is connected between the recovery bin and the elution bin, a lifting belt is arranged in the channel, the lifting belt lifts and transports the adsorption particles in the recovery bin to the direction of the elution bin, the elution bin discharges the eluent, and the adsorption particles on the lifting belt are subjected to countercurrent elution;
the eluted adsorption particles are discharged from the second input port into the column.
Compared with the prior art, the invention has the beneficial effects that:
the invention utilizes the micro-electrolysis-Fenton reagent combination to treat the traditional Chinese medicine preparation wastewater, adopts chemical battery reduction and free radical oxidation to degrade macromolecular organic matters together, adds hydrogen peroxide after the iron-carbon reaction according to the principle, and Fe generated by the anode reaction can be used as a catalyst for the subsequent catalytic oxidation treatment, namely Fe and hydrogen peroxide form a Fenton reagent oxidation system; the method for reducing COD and chroma of the wastewater provides a stable operation method for further biochemical treatment.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment is as follows: referring to fig. 1, this embodiment of a method for treating wastewater containing ginseng filtrate adopts a ginseng extract production plant, wherein the mixed solution of the ginseng filtrate in the plant has COD =9100mg/L, BOD =3861, and pH = 5.9;
(1) adjusting the pH value of the mixed liquor of the production wastewater of the ginseng extract to 3.0-5.0 by using dilute sulfuric acid, adding 60-80 meshes of iron powder and carbon powder, wherein the adding amount of the iron powder is 2.0% of the mass of the wastewater, the volume ratio of the iron powder to the carbon powder is 1:1, reacting for 4.0h, supplementing the dilute sulfuric acid in the reaction process to maintain the pH value at 3.0-5.0, and obtaining a treatment solution I after the reaction is finished;
(2) slowly adding 3% of hydrogen peroxide with the mass fraction of 30% into the treatment fluid I after micro-electrolysis, and oxidizing for 1h at the water temperature of 20-30 ℃ to obtain a treatment fluid II;
(3) adjusting the pH of the treatment liquid II to 8-9 by using sodium hydroxide, consuming 1.8% of liquid alkali, adding 0.003% of PAM, and quickly stirring for 10s at a quick stirring speed of 120-180 r/min; then slowly stirring for 10-20 min for sedimentation, wherein the slow stirring speed is 15-40 r/min, and filtering to obtain filtrate III;
(4) obtaining filtrate III, adding 0.05% of adsorption particles such as molecular sieve and activated carbon material, adsorbing for 20min at the rotation speed of 150r/min of a stirrer, and filtering to obtain filtrate IV;
(5) and discharging the filtrate IV after biochemical treatment or mixing with the municipal sewage for biochemical treatment.
The effluent water of the ginseng filtrate treated by the steps has COD =1180mg/L, BOD =880 mg/L, pH =8.1 and COD removal rate of 87%, so that the stability is further improved for biochemistry;
in addition, in order to adapt to the treatment method, the existing filter tower is improved, and the method comprises the following specific steps:
comprises a filter tower, wherein the filter tower is used for adsorbing filtrate III;
referring to fig. 2, a filter bin 1 is installed in the filter tower, the filter bin 1 is filled with adsorption particles, a driving box 100 is arranged at the bottom of the filter bin 1, and a driving mechanism in the driving box 100 drives the filter bin 1 to rotate around the center of the driving box 100;
two input ports are arranged at the top of the filter tower, filtrate III is obliquely sprayed out from the first input port 9, adsorption particles are obliquely sprayed out from the second input port 10, the spraying directions of the filtrate III and the adsorption particles are intersected, so that the filtrate III and the adsorption particles are mixed in the air and finally enter the filter bin 1, the adsorption particles are retained and stored by the adsorption bin 1, and the filtrate III is filtered out from the adsorption bin 1.
In the prior art, a filtering layer is generally formed in the middle of a filtering tower, and filtered liquid is sprayed from the top to the bottom and is filtered by the filtering layer.
In the design of the embodiment, a system capable of replacing the adsorption particles on line is arranged, so that the rotation input of the adsorption particles is arranged at the input end of the filtrate III, and the adsorption particles are firstly contacted during the input. When the two materials are sprayed out, a speed difference is formed, so that the principle similar to countercurrent adsorption is caused; is favorable for improving the adsorption efficiency.
After primary filtration, the filtrate enters the adsorption bin 1 together, adsorption particles stay in the adsorption bin 1, and filtrate III is filtered by the adsorption bin 1 and then is output;
another bright point of the present embodiment is the online replacement function of the adsorption particles in the adsorption bin 1; the adsorption particles in the adsorption tank can be replaced without stopping the adsorption tank, so that the adsorption effect is prevented from being influenced after adsorption saturation;
the specific design is as follows: a main gear 2 is installed in the driving box 100, a rack is arranged on the inner wall of the filtering tower, the main gear 2 is fixedly installed on the rack, the bottom of the bin wall of the filtering bin 1 is connected with an underframe 101, a planet wheel 3 is installed on the underframe 101, the planet wheel is meshed with the main gear 2 and is driven by a motor to rotate around the main gear, so that the filtering bin 1 is driven to rotate around the center of the main gear 2;
a transition wheel 4 is arranged on one side of the planet wheel 3, the transition wheel 4 is rotatably connected to the bottom frame 101 and meshed with the planet wheel 3, the transition wheel 4 is hinged with a connecting rod 5, and the end part of the connecting rod 5 is hinged with a discharge plate 6;
the bottom of the filter bin 1 is provided with a material discharging bin 7, the material discharging bin 7 is of a fixed structure and does not rotate along with the filter bin 1, the material discharging bin 7 is communicated with the filter bin 1 through an upper opening, openings are formed in two sides of the material discharging bin 7, adsorption particles falling into the material discharging bin 7 are pushed out of the material discharging bin 7 through a material discharging plate 6, and the material discharging bin 7 enters a recovery bin 8 arranged on the wall of the filter tower.
Regarding the arrangement of the discharge bin 7, the prior art adopts the method that the adsorbed particles are collected in a centralized way at the bottom of the tower and then are pumped out of the tower through a pipeline; this poses a problem that when the adsorption particles are extracted, the solution inside is inevitably extracted, and the system cannot determine whether the extracted solution is completely adsorbed; in another case, if the adsorbed particles are collected at the bottom of the tower, the bottom of the tower must be modified, for example, a tapered bottom is preferably formed to facilitate the concentration of the adsorbed particles; this further increases costs and further modifications are required if the modification of the column bottom would also lead to problems with the discharge of effluent;
the idea of the embodiment is that the filter bin 1 is arranged at the middle part, then the discharge bin is arranged at the bottom of the filter bin 1, and the adsorption particles at the bottommost layer are discharged in the discharge bin; this process is continued, i.e. the filtration cartridge 1 filters the solution normally, and the bottommost adsorbed particles must be the longest in adsorption time and the fastest saturated, and should therefore be discharged for replacement.
In addition, the discharge direction is selected to be transverse discharge and is vertical to the liquid flow direction, so that the discharge of the solution can be avoided as much as possible, and moreover, the discharge direction is the bottommost part of the filter bin, and even if part of the solution discharged liquid has no great influence.
In a specific structure, referring to fig. 4, the discharge bin 7 is located in the filter bin 1 and is rotatably connected with the filter bin 1, a discharge groove is formed in the bottom of the discharge bin 7, the discharge plate 6 is slidably connected in the discharge groove, and the bottommost adsorption particles are gathered in the discharge groove and discharged out of the tower along with the sliding of the discharge plate 6; the discharge groove is a rectangular groove, and as shown in the figure, the two ends of the groove are open; the material discharging bin 7 can be arranged to be a cylindrical structure at the upper part and matched with the bin wall of the filtering bin, and the lower part is obliquely and transitionally called a square material discharging groove of a factory, so that the concentration of the adsorbed particles is facilitated.
The bottom side wall of the filter bin 1 is provided with a notch 102, the side wall of the filter tower is symmetrically provided with two through grooves, and the two through grooves are communicated with the recovery bin 8.
An elution bin 12 is arranged at the top of the filtering tower, elution is contained in the elution bin 12, a channel is connected between the recovery bin 8 and the elution bin 12, a lifting belt is arranged in the channel, the lifting belt extracts the adsorption particles in the recovery bin 8 and transports the adsorption particles to the elution bin 12, the elution bin 12 discharges the elution, and the adsorption particles on the lifting belt are subjected to countercurrent elution;
the adsorbent particles that have completed elution are discharged from the second inlet 10 into the column.
The working principle is described in detail below with reference to the above description and the attached drawings: in operation, as shown in fig. 2-4, the motor is started to drive, the planet wheel 3 rotates around the main gear 2 with the wall of the filter bin 1, and a mechanism similar to a crank block composed of the transition wheel 4, the connecting rod 5 and the discharge plate 6 slides back and forth in the discharge chute. The entire mechanism is configured such that when the gap 102 is rotated into abutment with the right-hand side (the left and right hand side are described with reference to fig. 3 only) of the recovery bin, the discharge plate 6 is just pushed towards the right; when the notch 102 is rotated into abutment with the left recovery bin, just the discharge plate 6 is pushed towards the left.
The adsorption particles return to the top of the tower from the recovery bin 8 according to the design of the lifting belt and then are sprayed downwards, and the filtering bin 1 slowly rotates all the time, so that the adsorption particles can uniformly enter the adsorption bin 1 and stay.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.