Study on the Advanced Treatment Secondary Effluent of WWTPs by Coagulation

2011 ◽  
Vol 142 ◽  
pp. 165-168
Author(s):  
Yue Liu ◽  
Fu Xiang Li ◽  
Chun Peng Zhang
Keyword(s):  
Removal Rate ◽  
Advanced Treatment ◽  
Secondary Effluent ◽  
Optimal Dosage ◽  
Laboratory Results

The secondary effluent of WWTPs can be treated by the coagulation advancedly. The laboratory results showed that, PFS and PAC had lower efficient for the treatment of pollutants, and the effluent can not meet the requirements, so they were not s uitable as the coagulant. The PSFA, produced by the laboratory, had a higher removal rate of pollutants, and the quality of effluent can meet the relevant requirements of the standards, so it can be used as the coagulant of advanced treatment. The results of the experiment showed that the optimal dosage of PSFA was 20mg/L, and the COD, SS, turbidity, chromaticity, and TP of effluent were 9.5mg/L, 4.9mg/L, 2.7NTU, 10times and 0.15mg/L respectively.

Advanced Oxidation Treatment of Papermaking Wastewater by Homogeneous Fenton Reaction

2013 ◽  
Vol 726-731 ◽  
pp. 2510-2514 ◽  
Author(s):  
Hong Ping He ◽  
De Li Wu
Keyword(s):  
Removal Rate ◽  
Paper Industry ◽  
First Grade ◽  
Advanced Treatment ◽  
Treatment Processes ◽  
Quality Of Water ◽  
Optimum Reaction ◽  
Oxidation Technology ◽  
Papermaking Wastewater

The quality of water from traditional two-stage biochemical treatment process of papermaking wastewater cannot meet the pollutants discharge standard of paper industry,therefore it is necessary to develop new advanced treatment processes to further treat the effluent. This paper adopts the homogeneous Fenton oxidation technology to treat the effluent from a secondary sedimentation tank of a papermaking factory by batch experiments. The optimum reaction conditions are H2O2dosage 6.54mmol/L, FeSO4.7H2O dosage 200mg/L, pH=3, t=1.5h and of all the experiments the dosage of polyacrylamide is 3ppm. The COD of the treated water is under 50mg/L and its removal rate can reach as high as 75.4%, the chroma almost falls to zero, the effluent meets the first grade of the national wastewater discharge standard. Therefore, the homogeneous Fenton is an effective alternative for papermaking wastewater advanced treatment, due to its high effect.

scholarly journals Degradation of norfloxacin in aqueous solution with UV/peroxydisulfate

2019 ◽  
Vol 79 (12) ◽  
pp. 2387-2394 ◽  
Author(s):  
Honghai Xue ◽  
Siyu Gao ◽  
Na Zheng ◽  
Ming Li ◽  
Xue Wen ◽  
...  
Keyword(s):  
Degradation Kinetics ◽  
Removal Rate ◽  
Inorganic Ions ◽  
Transformation Products ◽  
Neutral Condition ◽  
Advanced Treatment ◽  
Ultrapure Water ◽  
Toc Removal ◽  
Laboratory Results ◽  
Removal Technology

Abstract The frequent detection of antibiotics in water bodies gives rise to concerns about their removal technology. In this study, the degradation kinetics and mechanisms of norfloxacin (NOR), a typical fluoroquinolone pharmaceutical, by the UV/peroxydisulfate (PDS) was investigated. NOR could be degraded effectively using this process, and the degradation rate increased with the increasing dosage of PDS but decreased with the increasing concentration of NOR. In real water, the degradation of NOR was slower than that in ultrapure water, which indicated that laboratory results cannot be directly used to predict the natural fate of antibiotics. Further experiments suggested that the degradation of NOR was the most fast under neutral condition, the existence of HA or FA inhibited the degradation of NOR, and the presence of inorganic ions (NO3−, Cl−, CO32− and HCO3−) had no significant effect on degradation of NOR. Total organic carbon (TOC) removal rate (40%) indicated NOR was not completely mineralized, and six transformation products were identified, and possible degradation pathways of NOR had been proposed. It can be prospected that UV/PDS technology could be used for advanced treatment of wastewater containing fluoroquinolones.

Evaluate the Efficiency of Fenton Oxidation and the Coagulant Aids in Fenton-Flocculation Process

2011 ◽  
Vol 281 ◽  
pp. 191-194
Author(s):  
Xin Liang Liu ◽  
Chang Li Ouyang ◽  
Yun Xia Bai ◽  
Hai Nong Song ◽  
Shuang Fei Wang
Keyword(s):  
Waste Water ◽  
Removal Rate ◽  
Velocity Ratio ◽  
Advanced Oxidation ◽  
Fenton Oxidation ◽  
Advanced Treatment ◽  
Optimal Dosage ◽  
Fenton Reagent ◽  
Sludge Settling ◽  
Flocculation Process

Fenton-flocculation process as one of effective the advanced oxidation treatments was widely used and studied. In this paper, the efficiency of Fenton oxidation was evaluated by the velocity ratio of CODcr decreased to Fenton reagent consumed. The coagulant aids, PAC and PAM, were canalized by CODcr removal rate, transmittance of the supernatant, the flocculation ratio and sludge settling ratio in Fenton-flocculation process. As the results shown, comparing with flocculation by Fenton reagent, transmittance of the supernatant and flocculating ratio can reach 50% and 80% respectively. The optimal dosage of coagulant aids is PAC 60 mg/L or PAM 4mg/L. The efficiency of Fenton oxidation is decreased but not be increased by adding more Fenton reagent in the advanced treatment of waste water.

The fate of formaldehyde in sugar manufacture and in products

2015 ◽  
pp. 692-696
Author(s):  
Remi Aubry ◽  
Laurence Gasnot
Keyword(s):  
Sugar Industry ◽  
Common Knowledge ◽  
Microbial Populations ◽  
Optimal Dosage ◽  
Consumer Health ◽  
Microbiological Activity ◽  
Specific Process ◽  
Beet Sugar ◽  
Series Of Experiments

A study was carried out in six beet sugar factories in France during the 2012/13 sugar campaign. The objective was to assess the optimal dosage of formaldehyde solutions at specific process stages and in different existing factory set-ups in order to obtain the desired effect on microbial populations, without interference with the quality of the products. In addition harmlessness regarding consumer health was to be demonstrated. A series of experiments was conducted resulting in new data allowing refreshment of common knowledge and references existing regarding the use of formaldehyde solutions in the sugar industry. The effectiveness and convenience for controlling microbiological activity in beet sugar manufacture was assessed. Formaldehyde reduces sugar losses and protects in-process products without harming their further use, such as for ethanol production.

scholarly journals Effects of different drying rates on the physiological quality of Coffea canephora Pierre seeds

2005 ◽  
Vol 17 (2) ◽  
pp. 199-205 ◽  
Author(s):  
Sttela Dellyzete Veiga Franco da Rosa ◽  
Delacyr da Silva Brandão Júnior ◽  
Édila Vilela de Resende Von Pinho ◽  
André Delly Veiga ◽  
Luiz Hildebrando de Castro e Silva
Keyword(s):  
Water Content ◽  
Storage Temperature ◽  
Removal Rate ◽  
Coffea Canephora ◽  
Development Stage ◽  
Seed Vigor ◽  
Drying Rate ◽  
Physiological Quality ◽  
Drying Rates

Desiccation tolerance in seeds depends on the species, development stage and drying conditions, especially the water removal rate. Coffea seeds are considered of intermediate performance, because they tolerate relative dehydration compared to orthodox seeds and are sensitive to low temperatures. The objective of this study was to verify the effect of different drying rates on the viability and storability of Coffea canephora seeds. A complete randomized experimental design was used, in a factorial 3 x 5 x 2 design, with three drying rates (fast, intermediate and slow), five final mean water contents after drying (51, 42, 33, 22 and 15 %) and two storage temperatures (10 and 20°C). The germination and seed vigor assessments, using radicle protrusion, cotyledon leaf opening, seedling emergence and emergence speed index, were performed shortly after drying and after two and four months storage. It was observed that with reduction in the water content there was reduction in the germination values and seed vigor, for all the drying rates. The greatest reductions in physiological quality occurred when the seeds were dried quickly and the best results were obtained at the intermediate drying rate. There was an effect of drying rate and storage temperature on the physiological quality of the seeds, and lower germination and vigor values were observed in seeds with lower water content stored at 20°C. C. canephora seeds were tolerant to desiccation down to 15 % water content and can be stored for four months at 10°C. A temperature of 20ºC can be used to store C. canephora seeds, as long as the water content is not reduced to values below 22 % water content.

Lab Scale Study on Synergistic Disinfection of WWTPS Secondary Effluent by Ultrasonic and Ozone

2012 ◽  
Vol 433-440 ◽  
pp. 4751-4756 ◽  
Author(s):  
Hao Wu ◽  
Zi Fu Li ◽  
Xin Jin ◽  
Xin Zhao ◽  
Fu Rong Deng
Keyword(s):  
Reaction Time ◽  
Removal Rate ◽  
Research Direction ◽  
Synergistic Action ◽  
Color Removal ◽  
Secondary Effluent ◽  
Disinfection Methods ◽  
Number Of Microorganisms ◽  
New Research ◽  
Ozone Disinfection

Secondary effluent from WWTPS still contains a large number of microorganisms, therefore, disinfection is essential. There are many disadvantages in using traditional disinfection methods, so the combination of disinfection techniques is a new research direction. Ozone combined with ultrasound is one of them. In this experiment, the inactivation of the total coli forms, color removal and UV254 removal of secondary effluent by a combination of ultrasonic (frequency20 kHz; power100W) and ozone disinfection was investigated. The results show that the effect of the synergistic action of 30s US and ozone disinfection is superior to the effect of individual ozone disinfection. After 15min synergistic disinfection, the total coli forms inactivation rate is up to 99.9%, simultaneously color removal rate to 80% and UV254 removal rate to 52%. Compared with individual ozone disinfection, reaction time was reduced by 5 min.

Document Control Practices in 120 Clinical Laboratories

2009 ◽  
Vol 133 (6) ◽  
pp. 942-949
Author(s):  
Paul N. Valenstein ◽  
Ana K. Stankovic ◽  
Rhona J. Souers ◽  
Frank Schneider ◽  
Elizabeth A. Wagar
Keyword(s):  
Patient Outcomes ◽  
Clinical Laboratory ◽  
Standard Setting ◽  
Clinical Laboratory Improvement Amendment ◽  
Clinical Laboratories ◽  
Policies And Procedures ◽  
Laboratory Results ◽  
Control Failures

Abstract Context.—A variety of document control practices are required of clinical laboratories by US regulation, laboratory accreditors, and standard-setting organizations. Objective.—To determine how faithfully document control is being implemented in practice and whether particular approaches to document control result in better levels of compliance. Design.—Contemporaneous, structured audit of 8814 documents used in 120 laboratories for conformance with 6 generally accepted document control requirements: available, authorized, current, reviewed by management, reviewed by staff, and archived. Results.—Of the 8814 documents, 3113 (35%) fulfilled all 6 document control requirements. The requirement fulfilled most frequently was availability of the document at all shifts and locations (8564 documents; 97%). Only 4407 (50%) of documents fulfilled Clinical Laboratory Improvement Amendment requirements for being properly archived after updating or discontinuation. Policies and procedures were more likely to fulfill document control requirements than forms and work aids. Documents tended to be better controlled in some laboratory sections (eg, transfusion service) than in others (eg, microbiology and client services). We could not identify document control practices significantly associated with higher compliance rates. Conclusions.—Most laboratories are not meeting regulatory and accreditation requirements related to control of documents. It is not clear whether control failures have any impact on the quality of laboratory results or patient outcomes.

Achieving Highly Stable Removal Rate in Small Tool Polishing of Glass Lenses

2020 ◽  
Author(s):  
Urara Satake ◽  
Toshiyuki Enomoto ◽  
Teppei Miyagawa ◽  
Takuya Ohsumi
Keyword(s):  
Removal Rate ◽  
Industrial Applications ◽  
Polishing Process ◽  
The Stability ◽  
Sudden Decrease ◽  
Polishing Pads ◽  
Glass Lenses ◽  
Polishing Pressure ◽  
Small Tool

Abstract The demand for improving the image quality of cameras has increased significantly, especially in industrial applications, such as broadcasting, on-vehicle, security, factory automation, and medicine. Surface of glass lenses, which is a key component of cameras, is formed and finished by polishing using small tools. However, the existing small tool polishing technologies exhibit serious problems including an unstable removal rate with the accumulated polishing time. In concrete, low removal rate at the beginning of the polishing process and sudden decrease in the removal rate during the polishing process significantly deteriorate stability of the removal rate. To improve the stability of the removal rate, we proposed a vibration-assisted polishing method using newly developed polishing pads with titanium dioxide particles in the previous work. Polishing experiments on glass lenses confirmed that the variation in the removal rate was suppressed by the developed polishing method; however, the reason for the improvement, in concrete, the relation between the vibration of polishing pressure and the stability of the removal rate remains unknown. In this study, we investigated and clarified the effect of the vibration of polishing pressure on the surface conditions of polishing pads, which strongly affected removal rate.

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