CN112794570A - Method for treating wastewater generated in white peony root traditional Chinese medicine production - Google Patents

Abstract

The invention relates to a method for treating white peony root traditional Chinese medicine production wastewater, which comprises the following steps: dividing the white peony root traditional Chinese medicine production wastewater into cleaning wastewater and cooking and peeling wastewater according to the organic pollution load and the solid waste content; (II) filtering and filter-pressing the cleaning wastewater to obtain circulating water which is used as water supplement for the white paeony root cooking and peeling process and/or is used for adjusting the water quality and the water quantity of produced water after the cooking and peeling wastewater is subjected to solid waste removal; step three, performing classified filtration on the cooking peeling wastewater, dividing the filter residue into recoverable white paeony root, grinding aids and solid waste according to different filter residue particle sizes, directly performing a slicing procedure on the recoverable white paeony root, and returning the grinding aids to the cooking peeling procedure to obtain the solid waste with the water content of less than 10%; and (IV) producing water after removing solid waste from the digestion and peeling wastewater by using the filtrate obtained in the step (III), and performing internal electrolysis, anaerobic biochemical treatment and the like, wherein the final removal rate of COD, ammonia nitrogen and total nitrogen can reach more than 95%.

Description

Method for treating wastewater generated in white peony root traditional Chinese medicine production

Technical Field

The invention belongs to the technical field of medical wastewater treatment, and particularly relates to a method for treating white peony root traditional Chinese medicine production wastewater.

Background

The white peony root is a dry root of a Ranunculaceae plant peony, has the effects of protecting liver, resisting virus, enhancing immunity and the like, is one of common Chinese medicinal materials, and is prostate in the Chinese medicinal materials. At present, the processing process of the white paeony root traditional Chinese medicine generally comprises the processes of sorting, cleaning, cooking, peeling, slicing, drying and the like, a large amount of wastewater is generated in the processing process, the wastewater mainly comprises cleaning wastewater and cooking and peeling wastewater, the content of suspended matters in the wastewater is high, the wastewater contains chemical component substances such as paeoniflorin, benzoic acid, volatile oil, fatty oil, tanning, mucilaginous substances, proteins, phenols and the like, the components are complex, the biotoxicity is high, the chromaticity is deep, the treatment is difficult, the ecological environment is greatly damaged, the environmental protection treatment is required to be carried out on the wastewater, and the environment pollution is avoided. In addition, the waste water body discharged in the processing and production process of the white paeony root traditional Chinese medicine still contains a part of substances with medicinal effect values, if the substances are not recycled, on one hand, the loss of traditional Chinese medicine materials and low yield of the medicinal materials are caused, the water quality pollution is serious and the subsequent treatment is difficult because the lost medicinal material components are introduced into the water body, and simultaneously, a large amount of solid wastes such as dregs and sand grains are generated in the processing and production of the white paeony root traditional Chinese medicine, so that the solid waste disposal cost is high, and further, the overall production efficiency of the white paeony root traditional Chinese medicine.

Disclosure of Invention

Aiming at the problems, the invention provides a method for treating the white peony root traditional Chinese medicine production wastewater, which comprises the following steps:

dividing the white paeony root traditional Chinese medicine production wastewater into cleaning wastewater and cooking and peeling wastewater according to the organic pollution load and the solid waste content, and respectively collecting and classifying the cleaning wastewater, wherein the cleaning wastewater has smaller organic pollution load and smaller solid waste content; the boiling and peeling wastewater has larger organic pollution load and larger solid waste content;

(II) filtering and filter-pressing the cleaning wastewater to obtain circulating water which is used as water supplement for the white paeony root cooking and peeling process and/or is used for adjusting the water quality and the water quantity of produced water after the cooking and peeling wastewater is subjected to solid waste removal;

step three, performing classified filtration on the cooking peeling wastewater, dividing the filter residue into recoverable white paeony root, grinding aids and solid waste according to different filter residue particle sizes, directly performing a slicing procedure on the recoverable white paeony root, and returning the grinding aids to the cooking peeling procedure to obtain the solid waste with the water content of less than 10%;

and (IV) producing water after removing solid waste from the digestion and peeling wastewater by using the filtrate obtained in the step (III), and performing internal electrolysis and anaerobic biochemical treatment, wherein the final removal rate of COD, ammonia nitrogen and total nitrogen can reach more than 95%.

According to the method for treating the white paeony root traditional Chinese medicine production wastewater, the cleaning wastewater and the cooking and peeling wastewater with the maximum yield in the white paeony root traditional Chinese medicine processing process are respectively collected and classified according to the characteristics of water quality, and are subjected to harmless treatment, so that the cleaning wastewater has small organic pollution load and small solid waste content, and the cooking and peeling wastewater has large organic pollution load and large solid waste content. Therefore, the two kinds of waste water can be subjected to quality separation and flow separation treatment, so that the subsequent treatment and the reuse are facilitated, and the treatment efficiency is improved. The cleaning wastewater is simply filtered, and circulating water can be obtained and used for the white paeony root cooking and peeling process again; meanwhile, as the yield of the cleaning wastewater is high, the pollution is low, the filtrate yield of the boiling and peeling wastewater after filtration is low, the concentration of organic pollutants is high, the circulating water and the produced water after solid waste removal of the boiling and peeling wastewater are mixed, the purposes of adjusting the water quality and the water quantity are achieved, the toxicity and the organic pollution load are reduced, and the biochemical treatment can be directly carried out after further coagulation and internal electrolysis reaction treatment.

In addition, the invention adopts a procedure of first physics and then chemistry for the cooking and peeling wastewater. For solid matters, the white paeony root traditional Chinese medicine is recovered according to different filter residue particle sizes, so that the yield of the white paeony root traditional Chinese medicine is improved; the grinding aid is recycled, so that the production efficiency of peeling of medicinal materials is improved, the consumption of auxiliary materials of the grinding aid in the peeling process of traditional Chinese medicines is reduced, and the consumption cost of the auxiliary materials is saved; through the two previous rounds of filtration, filter residues are greatly reduced, the reduction of solid waste is realized, and meanwhile, the graded filtration of the invention can also greatly reduce the water content of the solid waste. Compared with the traditional filtering process in which the water content of the solid waste is 70-80%, the water content of the solid waste obtained by the graded filtering provided by the invention is less than 10%, so that the subsequent storage, transportation and treatment of the solid waste are greatly facilitated.

And (3) refining the filtrate obtained in the step (three), wherein the filtrate still has the characteristics of complex chemical components, high biological toxicity and deep chromaticity.

Optionally, the step of filtering and filter-pressing the cleaning wastewater specifically comprises: cleaning wastewater firstly enters a cleaning wastewater collecting tank through a mechanical grid, and larger impurities and sludge are filtered; and pumping the wastewater into a first filter press through a mortar pump, wherein the effluent of the first filter press can enter a circulating water tank for collection, the cleaning wastewater is subjected to two-stage solid-liquid separation treatment including mechanical grating and filter pressing, impurities and silt in the water body are effectively removed, and the water body waits for returning to the white paeony root cooking and peeling procedure for reuse, or the filtrate obtained in the step (III) is input to adjust the water quality and the water quantity.

Optionally, the device used in the above process is: the water inlet of wasing the waste water collecting pit is equipped with mechanical grid, washs the bottom in waste water collecting pit and connects the mortar pump, and the first pressure filter of mortar pump rethread pipe connection, the delivery port of first pressure filter connect the circulation pond, be equipped with the three-way valve on the outlet conduit in circulation pond, the one end of three-way valve is passed through pipeline intercommunication white paeony root and is cooked the desquamation process, and the waste water mixed pool of filtrating is deposited in the other end intercommunication.

Optionally, the grid gap of the mechanical grid is 1-3 cm.

Optionally, the step (iii) includes the following steps:

(1) filtering the cooking and peeling wastewater to obtain filter residue with the particle size of more than 1cm, drying the filter residue to be used as recyclable white paeony root, and directly entering a slicing process because the white paeony root is a clean medicinal material after being cooked and peeled;

(2) filtering to obtain 0.1-1cm of filter residue with moderate granularity and hardness, and returning to the radix Paeoniae alba steaming and peeling process as grinding aid;

(3) filtering to obtain filter residue with particle size smaller than 0.1cm, and treating as solid waste.

(4) And (3) during filtering, exchanging heat between the cooking and peeling wastewater and the circulating water recycled in the step (II) and used for the white paeony root cooking and peeling process, and recycling heat energy of the white paeony root cooking and peeling wastewater.

Optionally, the cooking and peeling wastewater is discharged from the cooker, and flows into the peeling wastewater collecting tank through the diversion trench, the top of the diversion trench is provided with a grid plate, grid holes are uniformly distributed on the surface of the grid plate, and the cooking and peeling wastewater flows into the diversion trench after being filtered by the grid plate. The diversion trench can realize the functions of diversion and filtration, and can primarily filter the stewing and peeling wastewater to remove solids with larger volume. Preferably, the aperture of the grid hole is 1-2cm, and the bottom of the diversion trench has an inclination angle of 10-30 degrees, so that the cooking and peeling wastewater can flow into the peeling wastewater collection pool without a delivery pump.

Optionally, the step (1) specifically comprises: (a) a water feed pump is arranged in the peeling wastewater collecting pool and is connected with a rotary drum grating machine through a pipeline to carry out primary solid-liquid separation to obtain filter residue with the particle size of more than 1 cm; (b) a slag storage groove is arranged below a slag outlet of the rotary drum grating machine, and filter residues stored in the slag storage groove are dried by a drying device; (c) and then the filter residue with large size and weight is obtained after being separated by a winnowing machine and is a white paeony root traditional Chinese medicine solid lump material with pharmacodynamic value, the filter residue is recovered and directly enters a slicing procedure, the obtained filter residue with small size and weight is used as solid waste and is fully dried, the reduction of solid waste is realized, the yield of white paeony root traditional Chinese medicine production is improved, and the cost of the later-stage solid waste treatment is reduced.

Preferably, the drying device is a disc type drying machine which uses steam or hot air for drying, and the wind pressure of the winnowing machine is 0.1-1 MPa.

According to the physical characteristics of the dried filter residue, namely the difference of the granularity and the quality of the recyclable medicinal materials and the solid wastes, the invention selects the winnowing machine with simple operation and low cost to carry out wind power separation: the wind power of a draught fan is used as winnowing power, the airflow generated by the rotation of a sorting wheel of the winnowing machine is used for enabling filter residue materials to be winnowed to rotate in the winnowing machine and carry out winnowing classification by means of granularity and gravity, and the filter residue materials are respectively discharged from different discharge outlets after being collected, so that the winnowing of filter residues with different granularities, qualities and types is realized.

Optionally, the step (2) specifically includes: (d) the water outlet of the rotary drum grating machine is connected with a cyclone desander, and the filtrate obtained by the rotary drum grating machine is subjected to secondary solid-liquid separation; (e) slurry discharged from a sand outlet at the bottom of the cyclone desander is input into a second filter press for filter pressing treatment, and waste clear liquid discharged from a liquid outlet of the second filter press enters a waste water mixing pool for collection; (f) solid sand grains discharged from a discharge opening of the second filter press are input into a vibrating screen, and after vibration and screening, the solid with the grain size of 0.1-1cm is used as a grinding aid and returned to the white paeony root cooking and peeling process for reuse; the solid with smaller particle size is used as solid waste.

The step (f) improves the production efficiency of peeling of the medicinal materials, reduces the consumption of grinding aid auxiliary materials in the traditional Chinese medicine peeling process and saves the consumption cost of the production auxiliary materials.

Optionally, a collecting tank is arranged between the cyclone desander and the second filter press and between the cyclone desander and the scraper centrifuge and used for collecting the produced water or slurry discharged by the previous step of equipment, and the intermediate process water is temporarily stored according to the yield of the actual cooking and peeling wastewater so as to deal with the condition of large fluctuation of the content of pollutants in the wastewater in different periods.

Optionally, the step (3) specifically includes: (g) a liquid outlet at the top of the cyclone desander is connected with a scraper centrifuge, and the filtrate obtained by the cyclone desander is subjected to three-stage solid-liquid separation; (h) a water outlet of the scraper centrifuge is connected with a wastewater mixing pool for collection, and filtrate obtained by filtering the scraper centrifuge is stored in the wastewater mixing pool; (i) the solid discharged from the discharge port of the scraper centrifuge is centrifugally dewatered, so that the water content in the obtained solid waste can be reduced to below 10%, and the reduction of the solid waste is realized.

Preferably, the rotating speed of the scraper centrifuge is 1500-.

According to the method for graded filtering of the cooking and peeling wastewater, the drum grating machine, the cyclone desander and the scraper centrifuge which have different filtering degrees are sequentially utilized to carry out three-stage filtering according to the particle size of solids contained in the wastewater and different purposes of the solids with different particle sizes, and the synergistic effect of means such as drying, filter pressing and the like is combined, so that the reduction of solid wastes is realized, the water content of the solid wastes is greatly reduced, and the storage and treatment of subsequent solid wastes are facilitated.

Optionally, the step (iii) may also be implemented by operating the heat exchange and fractionation integrated machine provided by the present invention, where the heat exchange and fractionation integrated machine includes a filtering unit, a heat exchange unit, and a separation unit, the filtering unit includes a strip-shaped water tank and a rotary filter perpendicular to the water flow direction in the water tank, and filter residue in the rotary filter can be poured onto a conveyor belt of the separation unit; the separation unit comprises a conveyor belt, the conveyor belt is provided with sieve pores with different apertures, a water collecting tank is arranged below the conveyor belt, and the water collecting tank is connected with a water tank of the filtering unit; the heat exchange unit is a shell-and-tube type, a water tank is used as a heat exchange shell pass, and a heat exchange tube pass is connected with a water outlet pipe of the circulating water tank.

Optionally, a water inlet of the heat exchange and classification integrated machine is arranged at one end of the filtering unit, the water inlet is connected with a water tank, and the white peony root cooking and peeling wastewater is introduced into the filtering unit. Preferably, the front end of the water tank is provided with a grid plate, grid holes are uniformly distributed on the surface of the grid plate, and the aperture of each grid hole is 1-3 cm.

Optionally, the rotary filter comprises a central rotating shaft and a plurality of filter meshes around the central rotating shaft, and the central rotating shaft is horizontally arranged above the water tank and is perpendicular to the water flow direction in the water tank; the filter net sheets are movably connected with the central rotating shaft and are uniformly arranged around the central rotating shaft along the circumferential direction, the filter net sheets are parallel to the central rotating shaft, the filter net sheets below the central rotating shaft extend into the water tank, and the bottom of the filter net sheets is slightly higher than the bottom of the water tank, so that the filter net sheets can flexibly rotate in the water tank.

Optionally, the mesh aperture of the filter mesh is smaller than 0.1cm, and the mesh aperture of the filter mesh is selected according to the actual situation of solid waste generated in the white peony root cooking and peeling process, so that solid matters in the white peony root cooking and peeling wastewater in the water tank can be captured.

Optionally, the filter screen has sunken radian, and filter screen is the ladle form promptly, and the opening of ladle form filter screen is back to the rivers direction, and waste water can flow into filter screen's recess promptly, and the filter residue is stayed in the net piece, and waste water passes the net piece and continues to flow along the basin, can accomplish the filtration, the central pivot need not external drive power, and rivers can promote the net piece to rotate to the effort of ladle form filter screen, have reduced the energy consumption.

The filter screen is movably connected with the central rotating shaft, the filter screen can use the central rotating shaft as a fulcrum to rotate the direction opposite to the spoon-shaped opening in a universal mode, so that after the filter screen is connected with filter residues in the water tank, the spoon-shaped opening faces upwards through rotation before the filter screen moves to the conveyor belt, and the filter residues are prevented from falling; when the filter screen moves above the conveyor belt, the spoon-shaped opening is turned downwards, and filter residues fall on the conveyor belt.

Optionally, the conveyor belt is arranged beside the water tank, and the height of the conveyor belt is not higher than the top surface of the water tank, so that filter residues connected with the filter screen sheets are convenient to form; the spoon-shaped opening of the filter mesh sheet is a water-facing surface and rotates along with the central rotating shaft; when the filter screen rotates to be perpendicular to the water flow direction, the filter screen starts to rotate while revolving along with the central rotating shaft, so that the spoon-shaped opening gradually faces upwards, and filter residues are prevented from falling; when the filter screen rotates to leave the waste water surface, the filter screen rotates to the position above the conveyor belt, so that the spoon-shaped opening faces downwards and faces the upper surface of the conveyor belt, and filter residues fall on the conveyor belt.

As described above, the rotary filter of the present invention is an important part for connecting the filtering unit and the separating unit, and filters solid waste from the water tank of the filtering unit by revolution and rotation of the filter mesh sheet around the central rotating shaft, and then transfers the solid waste to the conveyor belt of the separating unit for further classification and separation. The filtration mode is simple to rotary filter uses rivers as power, need not to dispose driving equipment in addition, practices thrift energy consumption and equipment occupation space.

Optionally, the separation unit comprises a conveyor belt, a water collecting tank, a vibration device, a drying device, a solid waste collecting tank, a grinding aid collecting tank and a recovery medicine box, wherein the water collecting tank, the vibration device, the solid waste collecting tank, the grinding aid collecting tank and the recovery medicine box are arranged below the conveyor belt; the water collecting tank is arranged below the front section of the conveyor belt and is used for collecting the wastewater which falls off from the conveyor belt by vibration, and the water collecting tank is connected with the water tank; drying equipment, solid useless collecting vat, grinding aid collecting vat and recovery medical kit establish the below at the conveyer belt of water catch bowl rear in proper order.

The conveying belt vibrates left and right under the action of the vibration device, and a small part of residual wastewater on the conveying belt is shaken off into the water collection tank and then returns to the water tank through the water collection tank; meanwhile, the filter residue on the conveyor belt is promoted to become loose, the dehydration is more sufficient, and the loose filter residue is beneficial to the subsequent drying process and the classifying and screening process; in addition, the conveyor belt always maintains the vibration device in the separation unit, so that the subsequent classification and screening processes can be performed.

Alternatively, the drying device may use a device having a heating function known at present, preferably a heating coil having a small volume, and the present invention is not particularly limited.

Optionally, the conveyor belt comprises an upper mesh layer and a lower mesh layer, the lower surface of the upper mesh layer is tightly attached to the upper surface of the lower mesh layer, and the upper mesh layer and the lower mesh layer are uniformly distributed with meshes with the same aperture; when the upper mesh layer and the lower mesh layer are completely superposed and stacked up and down, the mesh openings of the upper mesh layer and the lower mesh layer are completely staggered, so that the mesh openings of the conveyor belt are completely closed; go up the mesh layer or mesh layer down is equipped with pusher, and pusher can change relative position between them through promoting mesh layer or mesh layer down for the sieve mesh of upper and lower mesh layer presents the coincidence of different degree, thereby forms the sieve mesh of equidimension not, realizes hierarchical screening.

Optionally, the two sides of the conveyor belt are provided with protective nets, so that when the conveyor belt is prevented from vibrating, filter residues fall off from the two sides of the conveyor belt, residual wastewater in the filter residues is allowed to pass through, and the aperture of each mesh of each protective net is the same as that of each filter screen.

When the drive belt was in water catch bowl top and drying equipment top, upper and lower mesh layer completely coincided and is folded from top to bottom, and the sieve mesh of upper and lower mesh layer is misplaced completely for the sieve mesh of conveyer belt is closed completely, and the filter residue can not drop from the conveyer belt, mainly accomplishes drainage, loose and drying task.

When the conveyer belt moved to solid useless collecting vat top, pusher promoted mesh layer or mesh layer down for the mesh pore part coincidence of upper and lower mesh layer, thereby present less sieve mesh on the conveyer belt, preferably, the aperture of the coincidence sieve mesh that forms this moment is less than 0.1cm, through the vibrations of conveyer belt, and the solid of suitable particle diameter drops in solid useless collecting vat.

When the conveyer belt moved to grinding aid collecting vat top, pusher promoted mesh layer or mesh layer down for some coincidence in the sieve mesh of upper and lower mesh layer, thereby present medium size sieve mesh on the conveyer belt, preferably, the aperture of the coincidence sieve mesh that forms this moment is 0.1-1cm, through the vibrations of conveyer belt, and the solid of suitable particle diameter drops in the grinding aid collecting vat. The residual solid on the conveying belt is recoverable white paeony root, and the white paeony root falls into the recovery medicine box when moving to the end of the conveying belt.

Optionally, the heat exchange tube side of the heat exchange unit is arranged behind the rotary filter, wastewater flows through the heat exchange tube side after passing through the rotary filter, the water inlet end of the heat exchange tube side is connected with the water outlet pipe of the circulating water tank, the water outlet end of the heat exchange tube side is connected with the white peony root cooking and peeling process, and heat of the cooking and peeling wastewater is recovered.

And the water outlet of the water tank is the water outlet of the heat exchange and classification integrated machine and is connected with the wastewater mixing tank. The waste water in the waste water mixing tank has the characteristics of low yield and high pollutant concentration, and the invention inputs the water production-circulating water part after the cleaning waste water treatment into the waste water mixing tank, adjusts the water quality and water quantity of the filtrate, reduces the pollutant concentration and meets the water inlet requirement of biochemical treatment.

The step (IV) specifically comprises the following steps:

(5) the circulating water tank is connected with the waste water mixing tank through an overrunning pipeline, circulating water is input into the waste water mixing tank, and the water quality and the water quantity in the waste water mixing tank are adjusted; a jet aerator is arranged in the waste water mixing tank to promote the dissolution of organic and inorganic pollutants in the waste water and remove dissolved substances;

(6) the waste water mixing tank is sequentially connected with the coagulation reaction tank and the inner electrolytic tank, the waste water precipitates and removes fine solid suspended matters and organic pollutants attached to the fine solid suspended matters in the coagulation reaction tank, and then the organic matters are degraded in the inner electrolytic tank;

(7) the effluent of the inner electrolytic cell is sequentially input into an anaerobic reactor and an A/O reactor, and organic pollutants are degraded in the anaerobic bacteria activated sludge; a plurality of groups of microporous aeration discs are arranged in the A/O reactor, and the aeration quantity is adjusted to realize the removal of organic pollutants, ammonia nitrogen and total nitrogen in the wastewater;

(8) the water outlet of the A/O reactor is input into an air floatation tank, a water distribution weir is arranged at the water inlet of the air floatation tank, the bottom of the air floatation tank is in a continuous W-shaped groove shape, and when the fluctuation of the water quality of the inlet water is large, a medicament adding device of the air floatation tank is started to add a water purification medicament, so that the stable operation of the system is ensured, and the water quality reaches the standard; the water discharged from the air floatation tank is the final produced water.

The invention uses the surpassing pipeline to connect the cleaning wastewater treatment flow and the cooking peeling wastewater treatment flow, and because the grading filtration of the cooking peeling wastewater treatment flow comprises a plurality of devices, the invention uses the surpassing pipeline to connect the circulating water tank and the wastewater mixing tank, thereby being convenient for adjusting the water quality and the water quantity in the wastewater mixing tank in time. Preferably, a flow meter and a control valve are arranged on the overrunning pipeline.

Preferably, the jet aerator is uniformly arranged in the wastewater mixing tank in the step (5), is connected with an external jet pump, promotes the dissolution of organic and inorganic pollutants in the wastewater by using an air floatation technology, and scrapes out the dissolved substances by a belt or a scraper, so that the subsequent coagulation treatment is facilitated.

Optionally, the coagulant added into the coagulation reaction tank in the step (6) is quicklime, the flocculant is polyacrylamide, and the quicklime and the polyacrylamide are quantitatively and uniformly added into the coagulation reaction tank after being configured by a dispensing device, so that the fine suspended solids and organic pollutants attached to the fine suspended solids are precipitated and removed, and the water inlet requirement of the internal electrolytic tank is met.

Optionally, after the effluent of the coagulation reaction tank in the step (6) is precipitated by a precipitation tank, the effluent overflows to an inner electrolytic tank for advanced treatment. And the bottom of the sedimentation tank is connected with a sludge pump, the settled sludge is pumped to a sludge concentration tank, and finally, the sludge is subjected to filter pressing treatment by a third filter press.

Optionally, the interior of the inner electrolytic cell is uniformly filled with an iron-carbon filler, the iron-carbon filler comprises aggregate, fly ash and a catalyst, the aggregate is filiform Q235 steel, the fly ash provides carbon, the catalyst is copper powder and titanium powder, the catalyst and the fly ash are both powder and mixed into the aggregate, and the iron-carbon filler is calcined and sintered at high temperature and is constructed into a loose porous structure. The mass ratio of the aggregate to the fly ash in the iron-carbon filler is 1 (1-1.3), wherein the mass fraction of copper in the iron-carbon filler is 0.5-1.5%, and the mass fraction of titanium powder in the iron-carbon filler is 1-4%. The iron-carbon filler used in the invention has loose and porous structure, large specific surface area and more active sites, and can improve the electrolysis efficiency by matching with the catalyst.

After the step (6), compared with the water quality condition of the boiling and peeling wastewater, the removal rate of COD in the wastewater can reach 20%, the content of suspended solid is reduced by more than 85%, the chroma can be reduced by 50%, the residue of traditional Chinese medicine residues in the water body is reduced, the problem that the water quality of the water body is influenced by continuous curing reaction of the traditional Chinese medicine residues in the water body is avoided, the chroma of the water body of the wastewater is further reduced through the homogeneous catalytic reduction effect of iron-carbon micro-electrolysis in the internal electrolytic cell, the biodegradability of the wastewater is improved, the biotoxicity of the wastewater is reduced, and the subsequent biochemical treatment is facilitated.

Optionally, the anaerobic reactor in the step (7) is a UASB anaerobic reactor, and water distributors are uniformly distributed at the bottom of the UASB anaerobic reactor, so that the wastewater is promoted to be uniformly distributed in the reactor, and the treatment efficiency is improved; the pH value in the anaerobic reactor is 4-5, and the COD removal rate can reach more than 80% after the wastewater is subjected to UASB anaerobic treatment.

Active sludge of facultative bacteria and aerobic bacteria is arranged in the A/O reactor, aeration quantity is adjusted through the microporous aeration disc, an anoxic or aerobic environment is formed in the reactor alternately, and according to the characteristics of low COD and high ammonia nitrogen of inlet water of the A/O reactor, the time ratio of anoxic to aerobic is (12-17): 1.

Optionally, in the step (8), the bottom of the air floatation tank is uniformly provided with medicament feeding pipes and is connected with an external medicament feeding device, a water purification medicament can be added into the wastewater in the air floatation tank as required, and particularly, when the water quality of the inflow water is subjected to emergency situations such as large fluctuation and the like, the medicament feeding device can be started by the aid of the method, so that the wastewater purification treatment efficiency is improved, and the stable operation of the system and the standard treatment of the water quality are ensured. The medicament is selected from one or more of polyaluminium chloride, polyaluminum ferric sulfate, polyacrylamide, ferrous sulfate and ferrous chloride.

The bottom of the air floatation tank is in a continuous and uniformly distributed W-shaped groove shape, so that uniform air distribution at the tank bottom is facilitated.

After the cleaning wastewater and the cooking and peeling wastewater are treated by the treatment method, the effluent quality COD is less than 50mg/L, the ammonia nitrogen is less than 5mg/L, the total nitrogen is less than 15mg/L, the suspended matters are less than 10mg/L, the total phosphorus is less than 0.5mg/L, the chromaticity is less than 30, and the effluent meets the discharge standard of the pollution of the traditional Chinese medicine pharmaceutical industry water (GB 21906-2008).

Optionally, the air flotation tank is sequentially connected with the final sedimentation tank and the deep bed denitrification filter tank, a three-way valve is arranged at a water outlet of the final sedimentation tank, one end of the three-way valve is connected with a discharge outlet to discharge final produced water, and the other end of the three-way valve is connected with the deep bed denitrification filter tank through a by-pass pipeline and then connected with the discharge outlet through the deep bed denitrification filter tank. When the total nitrogen, suspended matters and total phosphorus of the water quality of the discharged water of the final sedimentation tank exceed the standard, the water quality of the wastewater treatment is improved and the standard reaching discharge is ensured by controlling through a three-way valve and carrying out deep security treatment through a deep bed denitrification filter by a bypass pipeline.

According to the method for treating the white peony root traditional Chinese medicine production wastewater, the cleaning water is recycled, and the cooking and peeling process and wastewater quality and quantity regulation are utilized; traditional Chinese medicine materials with medicinal effect values in the boiling and peeling wastewater are recycled, medicine residues are reduced, sand grains in the wastewater are recycled and used as grinding aids to be reused in the boiling and peeling process, the environment pollution caused by the wastewater is effectively avoided, the cyclic utilization of resources is realized, the generation amount of solid wastes is reduced, the production yield of the white paeony root traditional Chinese medicine materials is improved, the production cost is reduced, and the application and popularization values are very high; and (4) carrying out biochemical treatment on the filtrate subjected to the graded filtration so that the treated wastewater reaches the standard and is discharged.

Drawings

Fig. 1 is a process flow diagram of a method for treating wastewater from radix paeoniae alba traditional Chinese medicine production in example 1.

Fig. 2 is a process flow diagram of the method for treating wastewater from traditional Chinese medicine white peony root production described in example 2.

Fig. 3 is a schematic structural view (front side) of the heat exchange and fractionation integrated machine.

Fig. 4 is a schematic structural view (back) of the heat exchange and fractionation integrated machine.

In the attached drawing, 1 is a mechanical grating, 2 is a cleaning wastewater collecting tank, 3 is a first filter press, 4 is a circulating water tank, 5 is a grid plate, 6 is a diversion trench, 7 is a peeling wastewater collecting tank, 8 is a rotary drum grating machine, 9 is a slag storage tank, 10 is a tray dryer, 11 is a winnowing machine, 12 is a rotational flow desander, 13 is a first collecting tank, 14 is a second collecting tank, 15 is a second filter press, 16 is a vibrating screen, 17 is a scraper centrifuge, 18 is a wastewater mixing tank, 19 is a coagulation reaction tank, 20 is a sedimentation tank, 21 is a third filter press, 22 is an internal electrolytic tank, 23 is a UASB anaerobic reactor, 24 is an A/O reactor, 25 is an air flotation tank, 26 is a dosing device, 27 is a final sedimentation tank, 28 is a deep bed denitrification filter tank, 29 is a bypass pipeline, 30 is an overrunning pipeline, 31 is a flowmeter, 32 is a control valve, 33 is a water tank, 34 is a rotary filter, 341 is a central rotating shaft, 342 is filter screen piece, 35 is the conveyer belt, 351 is upper mesh layer, 352 is lower mesh layer, 36 is the water catch bowl, 37 is the heat transfer tube side, 38 is drying equipment, 39 is the collection vat of solid waste, 40 is grinding aid collecting vat, 41 is the recovery medical kit.

Detailed Description

Example 1

In this embodiment, taking 1000 tons/day of white peony root Chinese herbal wastewater as an example, 200 tons/day of cleaning wastewater and 800 tons/day of boiling and peeling wastewater, the flow of the method for treating white peony root Chinese herbal wastewater is shown in fig. 1, and includes the following steps:

(1) according to the organic pollution load and the solid waste content, the white paeony root traditional Chinese medicine production wastewater is divided into cleaning wastewater and cooking and peeling wastewater, wherein the cleaning wastewater has smaller organic pollution load and smaller solid waste content; the boiling and peeling wastewater has larger organic pollution load and larger solid waste content;

(2) filtering and filter-pressing the cleaning wastewater, wherein the obtained circulating water is used as water supplement for the white paeony root cooking and peeling process and/or is used for adjusting the water quality and the water quantity of the produced water after the cooking and peeling wastewater is removed of solid waste:

specifically, cleaning wastewater firstly enters a cleaning wastewater collecting tank 2 through a mechanical grid 1, and larger impurities and sludge are filtered; pumping the wastewater into a first filter press 3 through a mortar pump, wherein the effluent of the first filter press 3 can enter a circulating water tank 4 for collection, the cleaning wastewater is subjected to two-stage solid-liquid separation treatment including mechanical grating 1 and filter pressing, impurities and silt in the water body are effectively removed, and the wastewater waits for returning to the white paeony root cooking and peeling process for reuse, or the wastewater is input into the cooking and peeling wastewater to remove solid waste and then produce water so as to adjust the water quality and the water quantity;

the arrangement of the above-mentioned apparatus is: a mechanical grid 1 is arranged at a water inlet of the cleaning wastewater collection pool 2, a grid gap is 2cm, the bottom of the cleaning wastewater collection pool 2 is connected with a mortar pump, the mortar pump is connected with a first filter press 3 through a pipeline, a water outlet of the first filter press 3 is connected with a circulating water pool 4, a water outlet pipeline of the circulating water pool 4 is provided with a three-way valve, one end of the three-way valve is communicated with a white peony root cooking and peeling process through a pipeline, and the other end of the three-way valve is communicated with a wastewater mixing pool;

(3) the method comprises the following steps that cooking peeling wastewater is discharged from a cooker and flows into a peeling wastewater collecting pool 7 through a flow guide groove 6, a grid plate 5 is arranged at the top of the flow guide groove 6, grid holes are uniformly distributed on the surface of the grid plate 5, the aperture is 2cm, the cooking peeling wastewater flows into the flow guide groove 6 after being filtered by the grid plate 5, and the bottom of the flow guide groove 6 has an inclination angle of 30 degrees, so that the cooking peeling wastewater can flow into the peeling wastewater collecting pool 7 without a conveying pump;

(4) a water feed pump is arranged in the peeling wastewater collecting tank 7 and is connected with a rotary drum grating machine 8 through a pipeline to carry out primary solid-liquid separation to obtain filter residue with the particle size of more than 1 cm; a slag storage groove 9 is arranged below a slag outlet of the rotary drum grating machine 8, and filter residues stored in the slag storage groove 9 are dried by a disc type dryer 10 dried by hot air; separating by an air separator 11 to obtain white paeony root Chinese medicinal solid block materials with large size and weight as medicinal effect values, recovering, and directly performing slicing process to obtain filter residues with small size and weight as solid waste and fully drying, wherein the air pressure of the air separator is 0.1 MPa;

(5) the water outlet of the rotary drum grating machine 8 is connected with a cyclone desander 12, and the filtrate obtained by the rotary drum grating machine 8 is subjected to secondary solid-liquid separation; slurry discharged from a sand outlet at the bottom of the cyclone desander 12 is input into a second filter press 15 for filter pressing treatment, and clear wastewater discharged from a liquid outlet of the second filter press 15 enters a wastewater mixing pool 18 for collection; solid sand grains discharged from a discharge port of the second filter press 15 are input into a vibrating screen 16, and after vibration and screening, the solid with the grain diameter of 0.1-1cm is used as a grinding aid and returned to the white paeony root cooking and peeling process for reuse; solid with smaller grain size is used as solid waste;

(6) a liquid outlet at the top of the cyclone desander 12 is connected with a scraper centrifuge 17, and the filtrate obtained by the cyclone desander 12 is subjected to three-stage solid-liquid separation; the rotating speed of the scraper centrifuge 17 is 2000r/min, a water outlet is connected with the waste water mixing tank 18 for collection, and filtrate obtained by filtering the scraper centrifuge 17 is stored in the waste water mixing tank 18; the solid discharged from the discharge port of the scraper centrifuge 17 is subjected to centrifugal dehydration, and the water content of the obtained solid waste can be reduced to 5%, so that the reduction of the solid waste is realized.

(7) The circulating water tank 4 is connected with the waste water mixing tank 18 through an overrunning pipeline 30, circulating water is input into the waste water mixing tank 18, the water quality and the water quantity in the waste water mixing tank 18 are adjusted, and a flow meter 31 and a control valve 32 are arranged on the overrunning pipeline 30; a jet aerator is arranged in the wastewater mixing tank 18 and is connected with an external jet pump to promote the dissolution of organic and inorganic pollutants in the wastewater, and the dissolved substances are skimmed by a belt or a scraper to facilitate the subsequent coagulation treatment;

(8) the waste water mixing tank 18 is sequentially connected with a coagulation reaction tank 19 and an internal electrolytic tank 22, the waste water precipitates and removes fine suspended solid and organic pollutants attached to the fine suspended solid in the coagulation reaction tank 19, the added coagulant is quicklime, and the flocculant is polyacrylamide;

(9) the effluent of the coagulation reaction tank 19 enters an inner electrolytic tank 22 to degrade organic matters, iron-carbon filler is uniformly filled in the inner electrolytic tank 22 and comprises aggregate, coal ash and catalyst, the aggregate is filiform Q235 steel, the coal ash provides carbon, the catalyst is copper powder and titanium powder, the catalyst and the coal ash are both powder and mixed in the aggregate, and the iron-carbon filler is calcined and sintered at high temperature and is constructed into a loose porous structure;

the mass ratio of the aggregate to the fly ash in the iron-carbon filler is 1:1, wherein the mass fraction of copper in the iron-carbon filler is 0.5%, and the mass fraction of titanium powder in the iron-carbon filler is 1%;

(10) the effluent of the inner electrolytic cell 22 is input into a UASB anaerobic reactor 23 to degrade organic pollutants in anaerobic activated sludge, water distributors which are uniformly distributed are arranged at the bottom of the UASB anaerobic reactor 23, and the pH value is 4-5;

(11) the effluent of the UASB anaerobic reactor 23 enters an A/O reactor 24, activated sludge of facultative bacteria and aerobic bacteria is contained in the A/O reactor 24, aeration quantity is adjusted through a plurality of groups of microporous aeration discs, so that the time ratio of an anoxic environment to an aerobic environment alternately formed in the reactor is 12:1, and organic pollutants, ammonia nitrogen and total nitrogen in the wastewater are removed.

Example 2

The flow of the method for treating white peony root traditional Chinese medicine production wastewater of the embodiment is shown in fig. 2, and comprises the following steps:

a heat exchange step is added before the step (4) in the embodiment 1, namely, a peeling wastewater collecting pool 7 is used as a heat exchange shell pass (not shown), a heat exchange tube pass is arranged in the pool, the water inlet end of the heat exchange tube pass is connected with a circulating water pool 4, and the water outlet end of the heat exchange tube pass is connected with a digester of the white paeony root cooking peeling process, so that the cooking peeling wastewater exchanges heat with recycled circulating water for the white paeony root cooking peeling process, and the heat energy of the white paeony root cooking peeling wastewater is recycled;

in the step (5) of example 1, the slurry discharged from the sand outlet at the bottom of the cyclone sand remover 12 is fed into the second collecting tank 14, temporarily stored, and when a sufficient amount of slurry is collected, fed into the second filter press 15 to be subjected to filter pressing treatment.

In the step (6) of the embodiment 1, a liquid outlet at the top of the cyclone desander 12 is connected with the first water collecting tank 13, temporarily stored, and when enough filtrate is collected, the filtrate at different times is mixed, and after the water quality is uniform, the filtrate is input into the scraper centrifuge 17.

In the step (9) of example 1, the effluent of the coagulation reaction tank 19 is precipitated by the sedimentation tank 20, and overflows to the internal electrolytic cell 22 for advanced treatment, the bottom of the sedimentation tank 20 is connected with a sludge pump, the precipitated sludge is pumped to a sludge concentration tank, and finally, the sludge is subjected to filter pressing treatment by the third filter press 21.

After the step (11) of the embodiment 1, the effluent of the A/O reactor 24 is input into the floatation tank 25, and the water inlet of the floatation tank 24 is provided with a water distribution weir, so that the water inlet is uniform; aeration pipes and agent adding pipes are uniformly distributed at the bottom of the air floatation tank 24, the agent adding pipes are connected with an external agent adding device 26, and water purifying agents such as polyaluminium chloride, polyaluminium ferric sulfate, polyacrylamide, ferrous sulfate and ferrous chloride can be added into the wastewater in the air floatation tank; the bottom of the air floatation tank 24 is in a continuous and uniformly distributed W-shaped groove shape, which is beneficial to uniform air distribution at the tank bottom, and in addition, the tank bottom is added with chemicals in a mode of air distribution, which is beneficial to rapid dispersion and uniform distribution of the chemicals in the air floatation tank, and the effect of the chemicals is quick; when the quality of water of intaking takes place emergent emergency such as great fluctuation, the accessible starts charge device, improves the purification treatment efficiency of waste water, ensures that system steady operation and quality of water are up to standard to be handled.

The final sedimentation tank 27 and the deep bed denitrification filter 28 are sequentially connected behind the air flotation tank 24, the effluent of the air flotation tank 24 is input into the final sedimentation tank 27, a three-way valve is arranged at the water outlet of the final sedimentation tank 27, one end of the three-way valve is connected with a discharge outlet to discharge final produced water, and the other end of the three-way valve is connected with the deep bed denitrification filter 28 through a bypass pipeline and then connected with the discharge outlet through the deep bed denitrification filter 28. When the total nitrogen, suspended matters and total phosphorus of the water quality of the discharged water of the final sedimentation tank 27 exceed the standard, the water quality of the wastewater treatment is improved and the standard reaching discharge is ensured by controlling through a three-way valve and carrying out deep security treatment through a deep bed denitrification filter 28 by a bypass pipeline 29.

Example 3

In the method for treating the white peony root traditional Chinese medicine production wastewater, the heat exchange and fractionation integrated machine is used for realizing the fractional filtration of the wastewater, instead of the steps (2) - (6) in the embodiment 1, and other steps are the same as those in the embodiment 1.

As shown in fig. 3 and 4, the heat exchange and fractionation integrated machine comprises a filtering unit, a heat exchange unit and a separation unit, wherein the filtering unit comprises a strip-shaped water tank 33 and a rotary filter 34 perpendicular to the water flow direction in the water tank 33, and filter residue in the rotary filter 34 can be poured onto a conveyor belt 35 of the separation unit; the separation unit comprises a conveyor belt 35, the conveyor belt 35 is provided with sieve holes with different apertures, a water collecting tank 36 is arranged below the conveyor belt 35, and the water collecting tank 36 is connected with a water tank 33 of the filtration unit; the heat exchange unit is a shell-and-tube type, a water tank 33 is used as a heat exchange shell pass, and a heat exchange tube pass 37 is connected with a water outlet pipe of the circulating water tank 4.

The water inlet of the heat exchange and classification integrated machine is arranged at one end of the filtering unit, the water inlet is connected with the water tank 33, the cooking and peeling wastewater is introduced into the filtering unit, the front end of the water tank 33 is provided with a grate plate (not shown), grate holes are uniformly distributed on the surface of the grate plate, and the aperture of each grate hole is 3 cm.

The rotary filter 34 comprises a central rotating shaft 341 and six filter meshes 342 at the periphery, wherein the central rotating shaft 341 is horizontally arranged above the water tank 33 and is vertical to the water flow direction in the water tank 33; the filter mesh 342 is movably connected with the central rotating shaft 341 and is uniformly arranged around the central rotating shaft 341 along the circumferential direction, the filter mesh 342 is parallel to the central rotating shaft 341, the filter mesh 342 below the central rotating shaft 341 extends into the water tank 33, and the distance between the bottom of the filter mesh 342 and the bottom of the water tank 33 is 0.5mm, so that the filter mesh 342 flexibly rotates in the water tank 33.

The mesh aperture of the filter mesh 342 is 0.01cm, and solid substances in the boiled and peeled wastewater in the water tank 33 can be captured. Filter screen 342 has sunken radian, and filter screen 342 is the ladle form promptly, and the opening of ladle form filter screen is back to the rivers direction, and waste water can flow in filter screen 342's recess promptly, and the filter residue is stayed in the net piece, and waste water passes the net piece and continues to flow along the basin, can accomplish the filtration, and central pivot 341 need not external drive power, and rivers can promote the net piece rotation to the effort of ladle form filter screen 342, have reduced the energy consumption.

The filter mesh 342 is movably connected with the central rotating shaft 341, and the filter mesh 342 can rotate the opposite direction of the spoon-shaped opening in a universal manner by taking the central rotating shaft 341 as a fulcrum, so that after the filter mesh 342 is in a state of receiving filter residues in the water tank 33, the spoon-shaped opening is upward through rotation before the filter mesh moves to the conveyor belt 35, and the filter residues are prevented from falling; when the filter mesh 342 is moved above the conveyor belt 35, the spoon-like opening is turned downward, and the residue is dropped on the conveyor belt 35.

The conveyor belt 35 is arranged beside the water tank 33, and the conveyor belt 35 is flush with the top surface of the water tank 33 so as to be convenient for taking filter residues connected with the filter screen 342; the spoon-shaped opening of the filter mesh 342 is a water-facing surface and rotates along with the central rotating shaft 341; when the filter mesh 342 rotates to be perpendicular to the water flow direction, the filter mesh 342 starts to rotate while revolving along with the central rotating shaft 341, so that the spoon-shaped opening gradually faces upwards to avoid filter residues from falling; when the filter mesh 342 revolves to leave the waste water surface, the filter mesh 342 rotates above the conveyor belt 35 by its own rotation, so that the scoop-like opening faces downward and toward the upper surface of the conveyor belt, and the filter residue falls on the conveyor belt 35.

The separation unit comprises a conveyor belt 35, a water collecting tank 36, a vibration device (not shown), a drying device 38, a solid waste collecting tank 39, a grinding aid collecting tank 40 and a recovery medicine box 41, wherein the water collecting tank 36, the vibration device (not shown), the drying device, the solid waste collecting tank 39, the grinding aid collecting tank 40 and the recovery medicine box 41 are arranged below the conveyor belt 35; the water collecting tank 36 is arranged below the front section of the conveyor belt 35 and is used for collecting the waste water which falls off from the conveyor belt 35 by vibration, and the water collecting tank 36 is connected with the water tank 33; the drying device 38, the solid waste collecting tank 39, the grinding aid collecting tank 40 and the recovery medicine box 41 are sequentially arranged below the conveyor belt 35 behind the water collecting tank 36. The drying device 38 is a heating coil.

The conveyor belt 35 vibrates left and right under the action of the vibration device, firstly, a small part of the waste water remained on the conveyor belt 35 is shaken off into the water collection tank 36, and then returns to the water tank 33 through the water collection tank 36; meanwhile, the filter residues on the conveyor belt 35 are promoted to become loose, the dehydration is more sufficient, and the loose filter residues are beneficial to the subsequent drying process and the classifying and screening process; in addition, the conveyor 35 always maintains the vibrating device in the separating unit, thereby enabling the subsequent classifying and screening process.

The conveyor belt 35 comprises an upper mesh layer 351 and a lower mesh layer 352, the lower surface of the upper mesh layer 351 is tightly attached to the upper surface of the lower mesh layer 352, and mesh holes with the same aperture are uniformly distributed on the upper mesh layer 351 and the lower mesh layer 352; when the upper mesh layer and the lower mesh layer are completely superposed and stacked up and down, the mesh openings of the upper mesh layer and the lower mesh layer are completely staggered, so that the mesh openings of the conveyor belt 35 are completely closed; go up mesh layer 351 or mesh layer 352 down and be equipped with pusher (not drawn), pusher can change both relative position through promoting mesh layer 351 or mesh layer 352 down for the mesh of upper and lower mesh layer presents the coincidence of different degree, thereby forms the mesh of equidimension not, realizes hierarchical screening.

The both sides of conveyer belt 35 are equipped with the protection network (not drawn), and when preventing the conveyer belt vibration, the filter residue drops from the conveyer belt both sides, allows remaining waste water in the filter residue to pass through simultaneously, and the mesh aperture of protection network is the same with filter screen 342's aperture.

When drive belt 35 is in water catch bowl top and drying equipment top, upper and lower mesh layer coincide completely and superpose from top to bottom, and the sieve mesh of upper and lower mesh layer misplaces completely for the sieve mesh of conveyer belt is closed completely, and the filter residue can not drop from the conveyer belt, mainly accomplishes drainage, loose and drying task.

When conveyer belt 35 moved to solid useless collecting vat 39 top, pusher promoted mesh layer 351 or mesh layer 352 down for the mesh fraction coincidence of upper and lower mesh layer, thereby appear less mesh on the conveyer belt 35 and be less than 0.1cm, through the vibrations of conveyer belt 35, the solid of suitable particle diameter drops in solid useless collecting vat 39.

When conveyer belt 35 moved to grinding aid collecting vat 40 top, pusher promoted upper mesh layer 351 or lower mesh layer 352 for upper and lower mesh layer's sieve mesh partly coincide, thereby appear sieve mesh 0.1-1cm of medium size on conveyer belt 35, through the vibrations of conveyer belt 35, the solid of suitable particle diameter drops in grinding aid collecting vat 40. The remaining solids on the conveyor 35 are recoverable white peony roots, which fall into the recovery medicine boxes 41 when moving to the end of the conveyor 35.

The heat exchange tube pass 37 of the heat exchange unit is arranged behind the rotary filter 34, wastewater passes through the rotary filter 34 and then flows through the heat exchange tube pass 37, the water inlet end of the heat exchange tube pass 37 is connected with the water outlet pipe of the circulating water tank 4, and the water outlet end of the heat exchange tube pass 37 is connected with the white peony root cooking and peeling process to recover heat of the cooking and peeling wastewater. The water content of the solid waste obtained in this example was reduced to 9%.

Example 4

In the method for treating the white peony root traditional Chinese medicine production wastewater, the cleaning wastewater is filtered and filter-pressed in the step (2), the obtained circulating water is only used as the water supplement for the white peony root cooking and peeling process, and is not used for adjusting the quality and quantity of the produced water after the solid waste is removed from the cooking and peeling wastewater, and other steps are the same as those in the embodiment 1.

Example 5

In the method for treating wastewater from traditional Chinese medicine production of radix paeoniae alba of this embodiment, the mass ratio of the aggregate of the iron-carbon filler to the fly ash in step (9) is 1:1.3, wherein the mass fraction of copper in the iron-carbon filler is 1.5%, the mass fraction of titanium powder in the iron-carbon filler is 4%, and the other steps are the same as those in example 1.

Example 6

In the method for treating the white peony root traditional Chinese medicine production wastewater of the embodiment, the medicament adding pipe of the air flotation tank 25 is arranged at the top of the air flotation tank, the bottom of the air flotation tank is not provided with a W-shaped groove, and other steps are the same as those in the embodiment 2.

Comparative example 1

According to the method for treating the white peony root traditional Chinese medicine production wastewater in the comparative example, the cleaning wastewater and the cooking and peeling wastewater are mixed and then directly pass through the diversion trench to be subjected to graded filtration, namely the steps (1) and (2) in the embodiment 1 are not included, and other steps are the same as those in the embodiment 1.

Comparative example 2

The method for treating the white peony root traditional Chinese medicine production wastewater in the comparative example does not comprise the step (9) in the example 1, namely the effluent of the coagulation reaction tank is directly input into the UASB anaerobic reactor without passing through the internal electrolytic tank, and other steps are the same as those in the example 1.

TABLE 1 comparison of the effects of examples 1-6 and comparative examples 1-2

As can be seen from the above table, the method for treating the white peony root traditional Chinese medicine production wastewater provided by the invention can effectively treat COD, ammonia nitrogen, total nitrogen and chromaticity in the white peony root production wastewater, so that the treated wastewater reaches the discharge standard. And the traditional Chinese medicine materials and the dregs in the wastewater are recycled, so that the production yield of the white paeony root traditional Chinese medicine materials is improved, the production cost is reduced, the yield of solid wastes is effectively reduced, and the method has strong application and popularization values.

Claims (10)

1. A treatment method for white peony root traditional Chinese medicine production wastewater is characterized by comprising the following steps:

dividing the white paeony root traditional Chinese medicine production wastewater into cleaning wastewater and cooking and peeling wastewater according to the organic pollution load and the solid waste content, wherein the cleaning wastewater has smaller organic pollution load and smaller solid waste content; the boiling and peeling wastewater has larger organic pollution load and larger solid waste content;

(II) filtering and filter-pressing the cleaning wastewater to obtain circulating water which is used as water supplement for the white paeony root cooking and peeling process and/or is used for adjusting the water quality and the water quantity of produced water after the cooking and peeling wastewater is subjected to solid waste removal;

step three, performing classified filtration on the cooking peeling wastewater, dividing the filter residue into recoverable white paeony root, grinding aids and solid waste according to different filter residue particle sizes, directly performing a slicing procedure on the recoverable white paeony root, and returning the grinding aids to the cooking peeling procedure to obtain the solid waste with the water content of less than 10%;

and (IV) producing water after removing solid waste from the digestion and peeling wastewater by using the filtrate obtained in the step (III), and performing internal electrolysis and anaerobic biochemical treatment, wherein the final removal rate of COD, ammonia nitrogen and total nitrogen can reach more than 95%.

2. The process of claim 1, wherein the step (iii) comprises the steps of:

(1) filtering the cooking and peeling wastewater to obtain filter residue with the particle size of more than 1cm, drying the filter residue to be used as recyclable white paeony root, and directly entering a slicing process because the white paeony root is a clean medicinal material after being cooked and peeled;

(2) filtering to obtain 0.1-1cm of filter residue with moderate granularity and hardness, and returning to the radix Paeoniae alba steaming and peeling process as grinding aid;

(3) filtering to obtain filter residue with a particle size smaller than 0.1cm, and treating the filter residue as solid waste;

(4) and (3) during filtering, exchanging heat between the filtrate and the circulating water recycled in the step (II) and used for the white paeony root cooking and peeling process, and recycling heat energy of the white paeony root cooking and peeling wastewater.

3. The processing method according to claim 2, characterized in that the step (1) is specifically: (a) a water feed pump is arranged in the peeling wastewater collecting pool and is connected with a rotary drum grating machine through a pipeline to carry out primary solid-liquid separation to obtain filter residue with the particle size of more than 1 cm; (b) a slag storage groove is arranged below a slag outlet of the rotary drum grating machine, and filter residues stored in the slag storage groove are dried by a drying device; (c) and then the filter residue with large size and weight is obtained after being separated by a winnowing machine and is a white paeony root traditional Chinese medicine solid lump material with pharmacodynamic value, the filter residue is recovered and directly enters a slicing procedure, the obtained filter residue with small size and weight is used as solid waste and is fully dried, the reduction of solid waste is realized, the yield of white paeony root traditional Chinese medicine production is improved, and the cost of the later-stage solid waste treatment is reduced.

4. The processing method according to claim 3, characterized in that the step (2) is specifically: (d) the water outlet of the rotary drum grating machine is connected with a cyclone desander, and the filtrate obtained by the rotary drum grating machine is subjected to secondary solid-liquid separation; (e) slurry discharged from a sand outlet at the bottom of the cyclone desander is input into a second filter press for filter pressing treatment, and clear wastewater liquid discharged from a liquid outlet of the second filter press enters a wastewater mixing pool for collection; (f) solid sand grains discharged from a discharge opening of the second filter press are input into a vibrating screen, and after vibration and screening, the solid with the grain size of 0.1-1cm is used as a grinding aid and returned to the white paeony root cooking and peeling process for reuse; the solid with smaller particle size is used as solid waste.

5. The processing method according to claim 4, characterized in that the step (3) is specifically: (g) a liquid outlet at the top of the cyclone desander is connected with a scraper centrifuge, and the filtrate obtained by the cyclone desander is subjected to three-stage solid-liquid separation; (h) a water outlet of the scraper centrifuge is connected with a wastewater mixing pool for collection, and filtrate obtained by filtering the scraper centrifuge is stored in the wastewater mixing pool; (i) the solid discharged from the discharge port of the scraper centrifuge is centrifugally dewatered, so that the water content in the obtained solid waste can be reduced to below 10%, and the reduction of the solid waste is realized.

6. The processing method according to claim 5, wherein the step (IV) specifically comprises the steps of:

(5) the circulating water tank is connected with the waste water mixing tank through an overrunning pipeline, circulating water is input into the waste water mixing tank, and the water quality and the water quantity in the waste water mixing tank are adjusted; a jet aerator is arranged in the waste water mixing tank to promote the dissolution of organic and inorganic pollutants in the waste water and remove dissolved substances;

(6) the waste water mixing tank is sequentially connected with the coagulation reaction tank and the inner electrolytic tank, the waste water precipitates and removes fine solid suspended matters and organic pollutants attached to the fine solid suspended matters in the coagulation reaction tank, and then the organic matters are degraded in the inner electrolytic tank;

(7) the effluent of the inner electrolytic cell is sequentially input into an anaerobic reactor and an A/O reactor, and organic pollutants are degraded in the anaerobic bacteria activated sludge; a plurality of groups of microporous aeration discs are arranged in the A/O reactor, and the aeration quantity is adjusted to realize the removal of organic pollutants, ammonia nitrogen and total nitrogen in the wastewater;

(8) the water outlet of the A/O reactor is input into an air floatation tank, a water distribution weir is arranged at the water inlet of the air floatation tank, the bottom of the air floatation tank is in a continuous W-shaped groove shape, and when the fluctuation of the water quality of the inlet water is large, a medicament adding device of the air floatation tank is started to add a water purification medicament, so that the stable operation of the system is ensured, and the water quality reaches the standard; the water discharged from the air floatation tank is the final produced water.

7. The treatment method according to claim 6, wherein the interior of the inner electrolytic cell is uniformly filled with an iron-carbon filler, and the iron-carbon filler comprises aggregate, fly ash and a catalyst;

the aggregate is filiform Q235 steel, the catalyst is copper and titanium powder, the catalyst and the fly ash are both powder and mixed into the aggregate, and the iron-carbon filler is calcined and sintered at high temperature to form a loose porous structure;

the mass ratio of the aggregate to the fly ash in the iron-carbon filler is 1 (1-1.3), wherein the mass fraction of copper in the iron-carbon filler is 0.5-1.5%, and the mass fraction of titanium powder in the iron-carbon filler is 1-4%;

the boiling and peeling wastewater is discharged from a boiling device and flows into a peeling wastewater collecting pool through a flow guide groove, a grid plate is arranged at the top of the flow guide groove, grid holes are uniformly distributed on the surface of the grid plate, the boiling and peeling wastewater flows into the flow guide groove after being filtered by the grid plate, so that the flow guide and the filtering are realized, the aperture of each grid hole is 1-2cm, and the bottom of the flow guide groove has an inclination angle of 10-30 degrees.

8. The treatment method according to claim 1, wherein the step (three) is further realized by operating a heat exchange and fractionation all-in-one machine, wherein the heat exchange and fractionation all-in-one machine comprises a filtering unit, a heat exchange unit and a separation unit, the filtering unit comprises an elongated water tank and a rotary filter perpendicular to the water flow direction in the water tank, and filter residue in the rotary filter can be poured on a conveyor belt of the separation unit; the separation unit comprises a conveyor belt, the conveyor belt is provided with sieve pores with different apertures, a water collecting tank is arranged below the conveyor belt, and the water collecting tank is connected with a water tank of the filtering unit; the heat exchange unit is a shell-and-tube type, a water tank is used as a heat exchange shell pass, and a heat exchange tube pass is connected with a water outlet pipe of the circulating water tank.

9. The treatment method according to claim 8, wherein the rotary filter comprises a central rotating shaft and a plurality of filter meshes arranged on the periphery of the central rotating shaft, and the central rotating shaft is horizontally arranged above the water tank and is vertical to the water flow direction in the water tank; the filter net sheets are movably connected with the central rotating shaft and are uniformly arranged around the central rotating shaft along the circumferential direction, the filter net sheets are parallel to the central rotating shaft, the filter net sheets below the central rotating shaft extend into the water tank, and the bottom of the filter net sheets is slightly higher than the bottom of the water tank, so that the filter net sheets can flexibly rotate in the water tank.

10. The treatment method according to claim 9, wherein the separation unit comprises a conveyor belt, a water collecting tank, a vibration device, a drying device, a solid waste collecting tank, a grinding aid collecting tank and a recovery medicine box, wherein the water collecting tank, the vibration device, the grinding aid collecting tank and the recovery medicine box are arranged below the conveyor belt; the water collecting tank is arranged below the front section of the conveyor belt and is used for collecting the wastewater which falls off from the conveyor belt by vibration, and the water collecting tank is connected with the water tank; the drying equipment, the solid waste collecting tank, the grinding aid collecting tank and the recycling medicine box are sequentially arranged below the conveying belt behind the water collecting tank;

the conveying belt comprises an upper mesh layer and a lower mesh layer, the lower surface of the upper mesh layer is tightly attached to the upper surface of the lower mesh layer, and the upper mesh layer and the lower mesh layer are uniformly distributed with meshes with the same pore diameter; when the upper mesh layer and the lower mesh layer are completely superposed and stacked up and down, the mesh openings of the upper mesh layer and the lower mesh layer are completely staggered, so that the mesh openings of the conveyor belt are completely closed; go up the mesh layer or mesh layer down is equipped with pusher, and pusher can change relative position between them through promoting mesh layer or mesh layer down for the sieve mesh of upper and lower mesh layer presents the coincidence of different degree, thereby forms the sieve mesh of equidimension not, realizes hierarchical screening.

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