CN102557252B

CN102557252B - Treating method of typical PPCPs (Pharmaceutical and Personal Care Products)

Info

Publication number: CN102557252B
Application number: CN201010608033.6A
Authority: CN
Inventors: 胡翔; 凌绘; 孙治荣; 王家德
Original assignee: Beijing University of Chemical Technology
Current assignee: Beijing University of Chemical Technology
Priority date: 2010-12-28
Filing date: 2010-12-28
Publication date: 2014-04-16
Anticipated expiration: 2030-12-28
Also published as: CN102557252A

Abstract

The invention relates to a novel method for integrated electric field enhanced biodegradation of typical PPCPs. The integrated electric field enhanced biological method is to combine the electrochemical treatment process and the biofilm treatment process in one reactor. Typical PPCPs substances are degraded by electrochemical redox, and easily degradable organic intermediates are generated. The newly generated organic intermediates It is further degraded by microorganisms in the reaction system, and the final products are carbon dioxide and water. The integrated electric field enhanced biological method does not need to add chemical agents in the process of degrading typical PPCPs, so it will not cause secondary pollution, and because of the low voltage and current density of the applied electric field, there is no potential safety hazard, making this method easy to practical application . Through the optimization of process conditions, the appropriate applied electric field process conditions and biological treatment process conditions are determined, and the removal rate of typical refractory PPCPs by the integrated electric field enhanced biological method can reach up to 95%.

Description

The treatment process of a kind of typical PPCPs

Technical field

The present invention relates to a kind of water technology of novelty, it combines biological process and electrochemical process, has without the need for machine carbon source, the feature such as between redox ability high and microbial film and electrode mass transfer is efficient.It is a kind of method of efficient processing organic micro-pollution material.

Technical background

Medicine and personal-care supplies PPCPs comprise number of chemical material, are present in multiple prescribed and non prescribed medicine (as microbiotic, steroid, anodyne, depressor, soporific, diet pill etc.), soap, shampoo, toothpaste, perfume, skin care product, sunscreen, hair jelly, hair dye etc.

PPCPs in modern society consumption is very large, and the PPCPs not utilized completely by human body enters municipal effluent by excretion or bathing, and municipal effluent is one of the main source of PPCPs in ecotope.Nearly ten years, started to pay close attention to the pollution of PPCPs to environment abroad, research shows, synthetic musk material, photographic developer, microbiotic, oestrogenic hormon, anti-inflammation analgesic, disinfection sanitizer etc. and the closely-related PPCPs of human lives ubiquity in environment.More than 70 kind of PPCPs and meta-bolites thereof in municipal effluent, surface water, underground water and drinking water source, have been detected abroad.The scientist of the U.S. and Britain further studies discovery, and near sewage work and factory's sewage draining exit, the wild fish of water body has produced sex entanglement, a large amount of Malformed frogs.Scientist thinks, environmental hormone is main assailant, and PPCPs is one of important sources of environmental hormone.Research both at home and abroad finds that PPCPs may produce adverse influence to the shellfish immunity system in water surrounding, as the PPCPs such as triclosan may have a negative impact to the hemocyte function of bivalve and the activity of digestive gland enzyme in the structure and function generation of algae in fresh water environment and seawater, in addition, PPCPs also may have chronic toxic action to biologies such as the water fleas in water surrounding, as can be seen here, PPCPs may have toxicity to a lot of biologies in water surrounding, and may pass through tap water or food chain harm humans health, thereby the Transport And Transformation of this pollutant in environment and biological impact has been become to a new environmental problem that causes extensive concern.

The discharge of cutting down PPCPs is to solve one of main method of this environmental problem, but more it is disturbing, about the research of PPCPs control techniques just just starts, because its concentration is low and have special metabolisming property, traditional waste water treatment plant does not have obvious removal effect to quite a few PPCPs, up to now, people also do not find the technological method of effective control, elimination PPCPs material.

Electrochemical treatment technology, owing to not adding chemical reagent thereby can not produce secondary pollution, has broad application prospects in water and field of waste water treatment, be considerable technology it.Since CNT (carbon nano-tube) self-discovery, it has been the center that people pay close attention to always.Carbon nanotube has electroconductibility and complete surface tissue, thereby it is a kind of good electrode materials, and carbon nanotube electrode can promote biomolecules Electron Transfer, can obtain good treatment effect, and has higher current efficiency.Biomembrance process can be used to process the waste water of lower concentration.Integrated electric field-enhanced biotechnology is in conjunction with biomembrance process and electrochemical process and the new technology of getting up, can fully combine active sludge or biomembranous microorganism fixed growth and the higher redox ability of electrolytic process, and the advantage such as efficient mass transfer relation between the two, at aspects such as processing lower concentration Persistent organic pollutants, there is obvious advantage.

Summary of the invention

The present invention seeks to by integrated electric field-enhanced biological process, utilize its biology and electrochemistry acting in conjunction, adopt but be not limited to SBR and process typical difficult degradation PPCPs material

The method that integrated electric field-enhanced biological process of the present invention is processed typical difficult degradation PPCPs comprises the following steps:

(1) Biofilm Colonization.This test temperature is room temperature.The mass concentration of dissolved oxygen is that 2-3mg/L. adopts quick spoil disposal biofilm method to carry out biofilm.The active sludge biological that inoculation has been tamed is abundant mutually, and the mass concentration of mud is 3.2g/L, and SV is about 25%.The waste water of above-mentioned kind of mud and artificial preparation mixes and adds each reactor as the ratio of 2: 3 take muddy water volume ratio, after submergence filler Static Contact 24h. get rid of mud. start the biofilm of intaking.Influent COD is 500mg/L, and ammonia-nitrogen content is 10mg/L, pH furnishing 7.5 left and right, the cycle of operation is 12h, aeration 10h, standing 1h, water outlet, water inlet, filler starts biofilm, is algae green, but biofilm insecure, easily come off; After 2 weeks, biofilm is mature on the whole, and difficult drop-off, after launching in water, is fine hair shape, overworks the whole inwall of filler.

(2) electrode biomembrane domestication.After microbial film is stable, in reactor, adds electrode and pass into direct current.Starting stage voltage is 1V, electric current is 2mA, add small portion microbial death after electric field, discharge, in reactor, on battery lead plate, have the thick microbial film of one deck 2mm, on filler, also have certain thickness microbial film, by the above results can determine in reactor, growth has nitrifier and denitrifying bacteria on battery lead plate and soft-filler, domestication cultivation stage completes, and system run all right, formally enters experimental stage.

(3) after system run all right, in rising pipe, take out experiment water outlet, measure.The leading indicator of measuring has the COD value, ammonia nitrogen of concentration, the water outlet of PPCPs (Ibuprofen BP/EP, diclofenac) etc.

(4) by changing influent load, select best influent load value, experimental result shows that the less PPCPS of influent load (Ibuprofen BP/EP, diclofenac) removal effect is better.

(5) change strength of current, strength of current increases successively, is up to 50mA.Along with the increase of strength of current, removal effect increases gradually.The clearance of Ibuprofen BP/EP reaches as high as more than 74%, and the clearance of diclofenac reaches as high as more than 95%.

In reaction process, COD removal effect all can reach more than 95%, and ammonia nitrogen removal effect can reach more than 90%, meets national standard effluent quality.

Present method utilizes the electrochemistry of integrated electric field-enhanced biological process and biodegradable acting in conjunction to process as Ibuprofen BP/EP and diclofenac typical difficult degradation PPCPs.Characteristic and the advantage of present method are, do not need to add chemical agent, thereby can not produce secondary pollution, and because extra electric field voltage, current density are low, do not have potential safety hazard, make the method be easy to practical application; This method has very high removal effect to COD, ammonia nitrogen, and its cost is lower, economic and practical, is a method of effectively removing lower concentration PPCPs.

Be that drawings and Examples further describe the present invention below, but the invention is not restricted to following embodiment

Accompanying drawing explanation

Fig. 1 .. electrode biomembrane of the present invention is processed the artwork of PPCPS

Reference numeral

1, mixing section 2, penstock 3, peristaltic pump 4, reactor

5, graphite electrode plate 6, microbial film 7, power supply 8, wire

9, water output duct 10, second pond

Specific implementation method

In experiment, in the nutritive medium of 1L, adding Ibuprofen BP/EP and diclofenac to make its concentration is 1mg/L, and microbial film is tamed and cultivated 7-15 days, after microorganism is stable, then adds electric field.Voltage is 1V, and electric current is 5mA, tames and cultivates 7-15 days, makes microorganism adapt to, after electric field and specific waste water thereof, carry out experimental debugging completely.Reaction has adopted SBR intermittent loading, every day to carry out 3 cycles, aeration 5h, precipitation 2h, and water inlet water outlet is respectively 0.5h.Taking out experiment water outlet measures.

Claims

1. A method for the co-processing of typical PPCPs by electrochemical and biological action, which is characterized in that the coupling of electrochemical treatment process and biofilm treatment process is realized in the same reactor, and multiple action mechanisms of electrochemical, adsorption and microbial degradation are comprehensively played , to achieve efficient treatment of PPCPs without secondary pollution, it includes the following steps:

(1) Biofilm hanging film: the mass concentration of dissolved oxygen is 2-3mg/L, adopt the rapid sludge discharge film hanging method to carry out film hanging, inoculate the activated sludge that has been domesticated, and the mass concentration of sludge is 3.2g/L , the SV is 25%, the inoculated sludge and the artificially prepared water sample containing a certain concentration of typical PPCPs are mixed into the reactor at a ratio of 2:3 by volume ratio of sludge to water, and the filler is submerged and statically contacted for 24 hours. After the sludge is removed, start The film is formed in the water, the COD of the water is 500 mg/L, the ammonia nitrogen content is 10 mg/L, the pH is adjusted to 7.5, the operation cycle is 12 hours, the aeration is 10 hours, and the water is left for 1 hour. Green, but the hanging film is not firm and easy to fall off; after 2 weeks, the hanging film is mature and not easy to fall off. After being unfolded in water, it is fluffy and covers the entire inner wall of the filler;

(2) Electrode biofilm acclimatization: After the biofilm is running stably, add electrodes to the reactor and supply direct current. The initial voltage is 1V and the current is 2mA. After adding the electric field, a small part of microorganisms die and are discharged. There is a layer of 2mm thick biofilm on the plate, and there is also biofilm on the packing. It is confirmed that there are nitrifying bacteria and denitrifying bacteria growing in the reactor, on the electrode plate and packing.

(3) Using continuous flow or SBR process, under the appropriate external electric field, electrode spacing and dissolved oxygen concentration conditions, select the appropriate hydraulic retention time or operation cycle, sludge retention time according to the influent water quality, with a certain concentration of typical The water sample of PPCPs enters the reactor to be degraded, and the treated effluent enters the secondary sedimentation tank;

(4) The water sample entering the secondary sedimentation tank is drained after separation of mud and water;

Described typical PPCPs are ibuprofen, diclofenac;

The concentration of PPCPs in the treated water samples containing typical PPCPs is 0.2-20mg/L;

The reaction is carried out at room temperature;

Electrode materials are graphite and carbon nanotubes;

The applied electric field is direct current, and the current density on the electrode is not more than 5mA/cm ² ;

The distance between cathode and anode electrodes is controlled at 1-10cm;

In step (3), during aeration, the dissolved oxygen concentration in the reactor is controlled at 1-4 mg/L.