Viable but Non-culturable Bacteria in Bioreactorbased Pharmaceutical Wastewater

We aimed to investigate the composition and phylogenetic rela-tionships of the viable but non-culturable （VBNC） state bacteria in pharmaceutical wastewater. [Method] Soil filter was used for constructing bioreactor. Based on the resuscitation- and growth-promoting function of Resuscitation Promoting Factor （Rpf） for VBNC bacteria, VBNC bacteria were isolated by most probable number （MPN） method and dilution-plating method and 16S rRNA gene phylogenetic analysis was carried out. [Result] In MPN culture system, Rpf could promote the resuscitation and growth of some bacteria. There were VBNC advantage floras that sensitive to Rpf in pharmaceutical wastewater. The culturable VBNC bacteria in pharmaceutical wastewater consisted of high-GC gram-positive actinomycetes including genera Mi-crobacterium, Gordonia and Leucobacter, and gram-negative bacteria including gen-era Candidimonas, Xanthobacter and Aminobacter. Four strains （ZYM1, ZYM3, ZYZR4, ZYXR1） could be potential novel species. [Conclusion] This research re-vealed there were VBNC bacteria in pharmaceutical wastewater. These results could provide important ideas and methods for further studies on VBNC bacteria in the pharmaceutical wastewater, especial y the formation mechanism and recovery mech-anism of VBNC bacteria and the advanced degradation process improvement of pharmaceutical wastewater.

Experimental study on micro-electrolysis technology for pharmaceutical wastewater treatment

Experiments were conducted to study the role of micro-electrolysis in removing chromaticity and COD and improving the biodegradability of pharmaceutical wastewater. The results showed that the use of micro-electrolysis technology could remove more than 90% of chromaticity and more than 50% of COD and greatly improved the biodegradability of pharmaceutical wastewater. Lower initial pH could be advantageous to the removal of chromaticity. A retention time of 30 minutes was recommended for the process design of micro-electrolysis.

Preparation and application of pharmaceutical wastewater treatment by praseodymium doped SnO_2/Ti electrocatalytic electrode

Praseodymium was selected as a promoter for SnO2/Ti electrode to improve the electrocatalytic performance by electrodeposition in pharmaceutical wastewater treatment; the micrograph and the structure were characterized by SEM and XRD. Mixture uniform design was used in the optimization of the electrolytic conditions; mathematical model was established according to the rate of wiping COD off, which revealed the relationship between the current intensity, time of electrolysis, the amount of doped Pr, and the ratio of area （SnOJTi：Al）. On the basis of the analysis of the empirical model, the optimized parameters had been obtained; the rate of wiping COD off was up to 94.9%, it decreased from 392 to 20 mg/L. Experimental results showed that the electrocatalytic performance of the electrode doped with Pr was superior for the treatment of pharmaceutical wastewater.

Treatment of pharmaceutical wastewater containing recalcitrant compounds in a Fenton-coagulation process

The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.

Application of an immobilized microbial consortium for the treatment of pharmaceutical wastewater: Batch-wise and continuous studies

In the present investigation,a microbial consortium consisting of four bacterial strains was selected for the treatment of pharmaceutical industry wa stewater.The consortium was immobilized on a natural support matrixLuffa and used for the treatment of real-time pharmaceutical wastewater in batch and continuous processes.The batch process was carried out to optimize the culture conditions and monitor the enzymatic activity.An array of enzymes such as alcohol dehydrogenase,aldehyde dehydrogenase,monooxygenase,catechol 2,3-dioxygenase and hydroquinol 1,2-dioxygenase were produced by the consortium.The kinetics of the degradation in the batch process was analyzed and it was noted to be a first-order reaction.For the continuous study,an aerobic fixed-film bioreactor(AFFBR) was utilized for a period of 61 days with variable hydraulic retention time(HRT) and organic loading rate(OLR).The immobilized microbes treated the wastewater by reducing the COD,phenolic contaminants and suspended solids.The OLR ranged between(0.56±0.05) kg COD·m^(-3) d^(-1) to 3.35 kg COD·m^(-3)·d^(-1) and the system achieved an average reduction of 96.8% of COD,92.6% of phenolic compounds and 95.2% of suspended solids.Kinetics of the continuous process was interpreted by three different models,where the modified Stover Kincannon model and the Grau second-order model proved to be best fit for the degradation reaction with the constant for saturation value,k_(L) being 95.12 g·L^(-1)·d^(-1).the constant for maximum utilization of the substrate U_(max) being 90.01 g·L^(-1) d^(-1) and substrate removal constant KY was1.074 d^(-1) for both the models.GC-MS analysis confirmed that most of the organic contaminants were degraded into innocuous metabolite s.

Growth properties of mixed liquor suspended solids in SMBR for pharmaceutical wastewater treatment

This paper presents the performance results of a 366-day pilot-scale submerged membrane bioreactor (SMBR) for treating high-strength pharmaceutical wastewater. The study focuses on the growth properties of mixed liquor suspended solids (MLSS) in SMBR operated at high volumetric loading rates. The influences of MLSS on COD removal,sludge yield,oxygen utilization rates and sludge viscosity are studied. Results show that the bioreactor can be operated at higher volumetric loading rate with a low sludge yield. VSS/SS and observed sludge yield coefficient (Yo) present a decreasing trend with the decrease of hydraulic retention time (HRT) . Sludge oxygen utilization rate decreases with the increase of mixed liquor volatile suspended solids (MLVSS) . A mathematical model between sludge viscosity and MLSS is developed.

Effects of Influencing Factors on Fenton Oxidation of Antibiotic Pharmaceutical Wastewater by a Statistical Design Approach

A series of batch-scale experiments were completed to investigate the effects of operational parameters on chemical oxygen demand (COD) removal by Fenton reagent for antibiotic pharmaceutical wastewater (APW). The significance of five operational factors including the mass ratio of H2O2/COD (g/g), the mole ratio of H2O2/Fe2+ (mol/mol), initial pH, oxidation temperature T, and reaction time t were evaluated statistically by Box-Behnken design (BBD). It was found that the five parameters were all significant to the COD removal efficiency by t-test, as well as the interactions between mass ratio/reaction time and oxidation temperature/reaction. The optimal COD removal efficiency (89.50%) was achieved when the mass ratio of H2O2/COD and the mole ratio of H2O2/Fe2+ were 3.00 and 5.00 respectively, with pH value of 3.68 at 298K for 72min reaction. A quadratic regression model with 0.9907 regression coefficient (R2) was developed which had good agreement to the experimental data.

Life cycle assessment of homogeneous Fenton process as pretreatment for refractory pharmaceutical wastewater

The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-geneous Fenton process for the treatment of high salinity pharmaceutical wastewater.The potential environmental impacts were calculated using Simapro software implemen-ting the CML 2001 methodology with normalization factors of 1995 world.Foreground data obtained directly from the full-scale wastewater treatment plant and labora-tory were used to conduct a life cycle inventory analysis,ensuring highly accurate results.By normalized results,the Fenton process reveals sensitive indicators,primarily toxi-city indicators(human toxicity,freshwater aquatic toxicity,and marine aquatic toxicity),as well as acidification and eutrophication impacts,contributed by hydrogen peroxide and iron sludge incineration,respectively.Overall,hydrogen peroxide and iron sludge incineration contribute significantly,accounting for at least 78%of these indicators.In sludge treatment phase,treatment of iron mud and infrastructure of hazardous waste incineration plants were the key contributors of environmental impacts,adding up to more than 95%.This study suggests the need to develop efficient oxidation processes and effective iron sludge treatment methods to reduce resource utilization and improve environmental benefits.

Efficient photocatalysis of tetracycline hydrochloride(TC-HCl) from pharmaceutical wastewater using AgCl/ZnO/g-C_(3)N_(4) composite under visible light: Process and mechanisms

AgCl/ZnO/g-C_(3)N_(4), a visible light activated ternary composite catalyst, was prepared by combining calcination, hydrothermal reaction and in-situ deposition processes to treat/photocatalyse tetracycline hydrochloride(TC-HCl) from pharmaceutical wastewater under visible light. The morphological, structural, electrical, and optical features of the novel photocatalyst were characterized using scanning electron microscopy(SEM), UV-visible light absorption spectrum(UV–Vis DRS), X-ray diffractometer(XRD), Fourier transform infrared spectroscopy(FT-IR), X-ray photoelectron spectroscopy(XPS), and transient photocurrent techniques. All analyses confirmed that the formation of heterojunctions between AgCl/ZnO and g-C_(3)N_(4)significantly increase electron-hole transfer and separation compared to pure ZnO and g-C_(3)N_(4). Thus, AgCl/ZnO/g-C_(3)N_(4)could exhibit superior photocatalytic activity during TC-HCl assays(over 90% removal) under visible light irradiation. The composite could maintain its photocatalytic stability even after four consecutive reaction cycles. Hydrogen peroxide(H_(2)O_(2)) and superoxide radical(·O_(2)) contributed more than holes(h+) and hydroxyl radicals(·OH) to the degradation process as showed by trapping experiments. Liquid chromatograph-mass spectrometer(LC-MS) was used for the representation of the TC-HCl potential degradation pathway. The applicability and the treatment potential of AgCl/ZnO/gC_(3)N_(4)against actual pharmaceutical wastewater showed that the composite can achieve removal efficiencies of 81.7%, 71.4% and 69.0% for TC-HCl, chemical oxygen demand(COD) and total organic carbon(TOC) respectively. AgCl/ZnO/g-C_(3)N_(4)can be a prospective key photocatalyst in the field of degradation of persistent, hardly-degradable pollutants, from industrial wastewater and not only.

AOX contamination status and genotoxicity of AOX-bearing pharmaceutical wastewater

Adsorbable organic halogens（AOX） are a general indicator for the total amount of compounds containing organically bonded halogens. AOX concentrations and components were investigated along the wastewater treatment process in four large-scale pharmaceutical factories of China, and genotoxicity based on the SOS/umu test was also evaluated. The results showed that AOX concentrations in wastewater of four factories ranged from 4.6 to 619.4 mg/L, which were high but greatly different owing to differences in the raw materials and products. The wastewater treatment process removed 50.0%–89.9% of AOX, leaving 1.3–302.5 mg/L AOX in the effluents. Genotoxicity levels ranged between 2.1 and 68.0 μg 4-NQO/L in the raw wastewater and decreased to 1.2–41.2 μg 4-NQO/L in the effluents of the wastewater treatment plants（WWTPs）. One of the main products of factory I, ciprofloxacin, was identified as the predominant contributor to its genotoxicity. However, for the other three factories, no significant relationship was observed between genotoxicity and detected AOX compounds.

Bioaugmentation with a pyridine-degrading bacterium in a membrane bioreactor treating pharmaceutical wastewater

The bacterial strain Paracoccus denitrificans W12, which could utilize pyridine as its sole source of carbon and nitrogen, was added into a membrane bioreactor （MBR） to enhance the treatment of a pharmaceutical wastewater. The treatment efliciencies investigated showed that the removal of chemical oxygen demand, total nitrogen, and total phosphorus were similar between bioaugmented and non-bioaugmented MBRs, however, significant removal of pyridine was obtained in the bioaugmented reactor. When the hydraulic retention time was 60 hr and the influent concentration of pyridine was 250-500 mg/L, the mean effluent concentration of pyridine without adding W12 was 57.2 mg/L, while the pyridine was degraded to an average of 10.2 mg/L with addition of W12. The bacterial community structure of activated sludge during the bioaugmented treatment was analyzed using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE）. The results showed that the W12 inoculum reversed the decline of microbial community diversity, however, the similarity between bacterial community structure of the original sludge and that of the sludge after bioaugmentation decreased steadily during the wastewater treatment. Sequencing of the DNA recovered from DGGE gel indicated that sp., Sphingobium sp., Comamonas sp., and Hyphomicrobium sp. were the dominant organisms in time sequence in the bacterial community in the bioaugmented MBR. This implied that the bioaugmentation was affected by the adjustment of whole bacterial community structure in the inhospitable environment, rather than being due solely to the degradation performance of the bacterium added.

Quantification of multi-antibiotic resistant opportunistic pathogenic bacteria in bioaerosols in and around a pharmaceutical wastewater treatment plant

Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.

Achieving biodegradability enhancement and acute biotoxicity removal through the treatment of pharmaceutical wastewater using a combined internal electrolysis and ultrasonic irradiation technology

Actual pharmaceutical wastewater was treatedusing a combined ultrasonic irradiation (US) and iron/cokeinternal electrolysis (Fe/C) technology. A significantsynergetic effect was observed, showing that ultrasonicirradiation dramatically enhanced the chemical oxygendemand (COD) removal efficiencies by internal electrolysis.The effects of primary operating factors on CODremoval were evaluated systematically. Higher ultrasonicfrequency and lower pH values as well as longer reactiontime were favorable to COD removal. The ratio ofbiochemical oxygen demand (BOD) and COD (B/C) ofthe wastewater increased from 0.21 to 0.32 after US-Fe/Ctreatment. An acute biotoxicity assay measuring theinhibition of bioluminescence indicated that the wastewaterwith overall toxicity of 4.3 mg-Zn^(2+)·L^(-1) wasreduced to 0.5 mg-Zn^(2+)·L^(-1) after treatment. Both the rawand the treated wastewater samples were separated andidentified. The types of compounds suggested that theincreased biodegradability and reduced biotoxicityresulted mainly from the destruction of N,N-2 dimethylformamide and aromatic compounds in the pharmaceuticalwastewater.

Treatment of Wastewater from Pharmaceutical Intermittent Production by Fe/C-Fenton-Hydrolysis Acidification-A/O Process

The design and running effect of treatment of wastewater from pharmaceutical intermittent production by iron-carbon（Fe/C）-Fentonhydrolysis acidification-anoxic/aerobic（A/O）process were introduced.The results of continuous operation showed that when the flow rate of the influent wastewater was 300 m^3/d,after the influent high-concentration wastewater（CODCrand NH4＋-N concentration were 35 000 and 1 000 mg/L,respectively）and medium-concentration wastewater（CODCrand NH4＋-N concentration were 1 500 and 100 mg/L,respectively）were treated by the process,CODCrand NH4＋-N concentration in the effluent decreased to 360-410 and 20-25 mg/L,respectively,and the quality of the effluent could meet the Grade III standard of Integrated Wastewater Discharge Standard（GB 8978-1996）.The combined process was proved to be an effective method to treat wastewater from pharmaceutical intermittent production,and its operation was stable.

Micro-electrolysis technology for industrial wastewater treatment

Experiments were conducted to study the role of micro-electrolysis in removing chromaticity and COD and improving the biodegradability of wastewater from pharmaceutical, dye-printing and papermaking plants. Results showed that the use of micro-electrolysis technology could remove more than 90% of chromaticity and more than 50% of COD and greatly improved the biodegradability of pharmaceutical wastewater. Lower initial pH could be advantageous to the removal of chromaticity. A retention time of 30 minutes was recommended for the process design of micro-electrolysis. For the use of micro-electrolysis in treatment of dye-printing wastewater, the removal rates of both chromaticity and COD were increased from neutral condition to acid condition for disperse blue wastewater; more than 90% of chromaticity and more than 50% of COD could be removed in neutral condition for vital red wastewater.

Use of sub-micron sized resin particles for removal of endocrine disrupting compounds and pharmaceuticals from water and wastewater

Endocrine disrupting compounds（EDCs） and pharmaceuticals pose a challenge for water and wastewater treatment because they exist at very low concentrations in the presence of substances at much higher concentrations competing for adsorption sites.Sub-micron sized resin particles（approximately 300 nm in diameter）（SMR） were tested to evaluate their potential as a treatment for EDCs including：17-β estradiol（E2）,17-α ethinylestradiol（EE2）,estrone（E1）,bisphenol A（BPA）,and diethylstilbestrol（DES） as well as 12 pharmaceuticals.SMR were able to remove 98%of spiked E2,80%of EE2,87%of BPA,and up to 97%of DES from water.For a 0.5 ppm mixture of E2,EE2,E1,BPA and DES,the minimum removal was24%（E2） and the maximum was 49%（DES）.They were also able to remove the pharmaceuticals from deionized water and wastewater.Overall,SMR are a promising advanced treatment for removal of both EDCs and pharmaceuticals.

Glutamicibacter nicotianae AT6:A new strain for the efficient biodegradation of tilmicosin

The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low cost.Coincidently,we found a new strain,Glutamicibacter nicotianae sp.AT6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal efficiency.The role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM removals.The toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic substances.Based on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.

Degradation of kanamycin from production wastewater with high-concentration organic matrices by hydrothermal treatment

It is known that many kinds of fermentative antibiotics can be removed by temperatureenhanced hydrolysis from production wastewater based on their easy-to-hydrolyze characteristics.However,a few aminoglycosides are hard to hydrolyze below 100℃ because of their stability expressed by high molecular energy gap(E).Herein,removal of hard-to-hydrolyze kanamycin residue from production wastewater by hydrothermal treatment at subcritical temperatures was investigated.The results showed the reaction temperature had a significant impact on kanamycin degradation.The degradation half-life(t1/2)was shortened by 87.17-fold when the hydrothermal treatment temperature was increased from 100℃ to 180℃.The t1/2 of kanamycin in the N2 process was extended by 1.08-1.34-fold compared to that of the corresponding air process at reaction temperatures of 140-180℃,indicating that the reactions during hydrothermal treatment process mainly include oxidation and hydrolysis.However,the contribution of hydrolysis was calculated as 75%-98%,which showed hydrolysis played a major role during the process,providing possibilities for the removal of kanamycin from production wastewaters with high-concentration organic matrices.Five transformation products with lower antibacterial activity than kanamycin were identified using UPLC-QTOF-MS analysis.More importantly,hydrothermal treatment could remove 97.9%of antibacterial activity(kanamycin EQ,1,109 mg/L)from actual production wastewater with CODCr around 100,000 mg/L.Furthermore,the methane production yield in anaerobic inhibition tests could be increased about 2.3 times by adopting the hydrothermal pretreatment.Therefore,it is concluded that hydrothermal treatment as a pretreatment technology is an efficient method for removing high-concentration hard-to-hydrolyze antibiotic residues from wastewater with high-concentration organic matrices.

Effect of co-presence of NSAIDs with cadmium:i)evaluation of NSAIDbearing water for washing Cd from soil,ii)Cd removal from NSAIDbearing water using magnetic graphene oxide

Cadmium“Cd”is a toxic pollutant that may present in soil and water.This work evaluates:i)the use of non-steroidal anti-inflammatory drugs“NSAIDs”-bearing water for washing soil containing Cd(Ⅱ),ii)removal of Cd(Ⅱ)from NSAID-bearing water by adsorption onto magnetic graphene oxide which can be easily separated by strong magnet.The studied NSAIDs are aspirin,ketoprofen,ibuprofern and diclofenac.The Cd(Ⅱ)-NSAIDs complexes were synthesized and characterized by FT-IR.Graphene was initially oxidized by either nitric acid,or ammonium persulphate method,or Hummer's method.Magnetite was then deposited on graphene oxide to give the corresponding magnetic graphene oxides(NA-MGO,APSMGO and Hum-MGO,respectively).The effect of the following factors on Cd(Ⅱ)uptake was investigated:NSAIDs type,pH,graphene oxidation method,magnetite:graphene oxide mass ratio in the adsorbent,(Cd(Ⅱ):NSAID)molar ratio.Maximum Cd(Ⅱ)uptake was achieved using“magnetic graphene oxidized with ammonium persulphate where the mass ratio of magnetite to graphene oxide was 2:1”in the presence of diclofenac at pH6.The best Cd(Ⅱ):diclofenac molar ratio was 1:3.The maximum adsorption capacity of Cd(Ⅱ)was found to be 83 mg L1.The regeneration of the adsorbent was possible by 0.3 M HNO3 solution and 80%of adsorption efficiency was maintained after five cycles.Upon presence of coexisting ions,80%of the adsorption efficiency was maintained.Various NSAIDs-containing waters were used for washing Cd-containing soil;the maximum removal efficiencies of Cd were 18%and 16%using 5 mM diclofenac or 10 mM aspirin,respectively.Using diclofenac or aspirin-spiked real pharmaceutical wastewater gave 28%removal of Cd.The optimum adsorption method was used for removal of Cd(Ⅱ)from diclofenac-containing soil-washing water,where two successive adsorptions were needed for complete Cd uptake.