scholarly journals Design and performance of a coarse media, high hydraulic load polishing wetland for steel industry wastewater

2019 ◽  
Vol 80 (1) ◽  
pp. 59-66
Author(s):  
Viet Anh Nguyen ◽  
Minh Phuong Nguyen ◽  
Karin Tonderski ◽  
Hai Do Thi ◽  
Anh Thi Kim Bui
Keyword(s):  
Flow Rate ◽  
Steel Industry ◽  
Oxygen Demand ◽  
Head Loss ◽  
Design Flow ◽  
Total System ◽  
Pilot Test ◽  
Removal Efficiencies ◽  
And Performance ◽  
Industry Wastewater

Abstract This paper presents the design of a constructed wetland (CW) system in an area with limited land availability, resulting in high hydraulic loads. The CW was constructed to act as a buffering/ polishing step after stabilization ponds for steel industry wastewater post-treatment. A pilot test with two different filter media (50–100mm vs 40–60mm diameter) indicated that a flow rate increase from 49.5 m3/h to 122.4 m3/h would lead to a head loss increase from 2.9cm to 8.7cm, and more than double that for the finer gravel. This was substantially higher than the calculated theoretical values, though the relation with flow rate was similar. Four full scale wetland cells (CW1, CW2, CW3 and CW4) were constructed using the coarser gravel. A design value of total head loss of 1.01m over the total system length, with a design flow of 36,000 m3/day, was expected based on pilot test results. During the first operation year (September 2017 to July 2018), the pond-CW system has received wastewater already meeting required discharge standards. The effluent from the CWs had consistently lower concentrations of all measured variables, and met the predicted values for biochemical oxygen demand (BOD5), total nitrogen (TN) and NH4+-N. Highest removal efficiencies were achieved for NH4+-N (>90%), Mn (>60%) and Fe (45%) with removal efficiencies for TN (14%), BOD5 and chemical oxygen demand (COD) (around 30%). Concentrations of phenol, CN− and Cr6+ were below 10, 4 and 3μg/l, respectively, in in- and outflows. An appreciated benefit of the wetland was the ‘green element’ in the industrial landscape.

scholarly journals Evaluation and Performance of Activated Sludge Hi-Kleen Treatment Plant (ASHTP): A Case Study

2021 ◽  
Vol 11 (2) ◽  
pp. 15-24
Author(s):  
Nur Diana Wakimin ◽  
Juferi Idris ◽  
Lydia Dundun Francis ◽  
Maureen Neging ◽  
Siti Rafiqah Muskil ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Treated Effluent ◽  
Overall Performance ◽  
Removal Efficiencies ◽  
And Performance

Pollutants from sewage wastewater are major concerns due to their environmental effects. Thus, an effective sewage wastewater treatment plant is important to ensure discharged effluent is well treated before it can be released to rivers or water streams. This study aims to evaluate the performance of the Activated Sludge Hi-Kleen Treatment Plant (ASHTP) located at H Block (ASHTP at H Block) and L Block (ASHTP at L Block) in UiTM Sarawak Branch, Samarahan Campus, Sarawak, Malaysia. The evaluation was based on physicochemical and removal efficiency namely pH, temperature, turbidity, chemical oxygen demand (COD), and total suspended solids (TSS) from raw influent and treated effluent. The findings indicated that the overall performance of both ASHTP at H Block and L Block were satisfactory where treated effluent meets the standard discharge limits of Environmental Quality (Sewage) Regulations 2009 (Standard B). For ASHTP at H Block, the removal efficiencies of turbidity, COD, and TSS were found to be 86.00, 13.76, and 88.02% respectively, in which the pH, temperature, turbidity, COD, and TSS of the treated effluent were 7.30, 28.10°C, 10.40 NTU, 14.10 mg/L and 8.90 mg/L respectively. Meanwhile, for ASHTP at L Block, the removal efficiencies of turbidity, COD, and TSS were found to be 43.20, 41.90, and 51.61% respectively, in which the pH, temperature, turbidity, COD, and TSS in the treated effluent were 7.30, 27.90°C, 21.10 NTU, 58.10 mg/L and 18.00 mg/L respectively. Proper maintenance of sewage treatment plant is important to ensure its effectiveness as well as to prolong its lifespan.

Efficiency of Packed Cage RBC System for Treatment of Wastewater Containing Surfactants

2003 ◽  
Vol 38 (4) ◽  
pp. 737-752 ◽  
Author(s):  
Suntud Sirianuntapiboon ◽  
Panthong Srikattanaprom
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Sodium Dodecyl ◽  
Oxygen Demand ◽  
Biological Oxygen Demand ◽  
Rotating Biological Contactor ◽  
Cosmetic Industry ◽  
Removal Efficiencies ◽  
Triton X ◽  
Industry Wastewater

Abstract The chemical oxygen demand (COD) and five-day biological oxygen demand (BOD5) removal efficiencies of a packed cage rotating biological contactor (RBC) system under a hydraulic retention time (HRT) of 16 h declined from 93.90% to 78.58% and 78.61% and 96.27% to 84.83% and 87.93%, respectively, with an increase of sodium dodecyl sulphate (SDS) and triton X-100 loading from 0.00 to 1.25 mg/m2·d. Reactor no. 1 of the system changed to anaerobic when the system was operated under an HRT of 8 h with surfactant loading of up to 2.55 mg/m2·d. However, reactor no. 2 of the system was aerobic and the dissolved oxygen was higher than 3.00 mg/L. The study showed that this type of packed cage RBC system could be applied for treating the cosmetic industry wastewater with surfactant loading of up to 2.55 mg/m2·d under an HRT of 8 h.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

Radon removal by aeration: observations on testing, installation and maintenance of domestic treatment units

2009 ◽  
Vol 9 (4) ◽  
pp. 469-475
Author(s):  
T. Turtiainen
Keyword(s):  
Water Quality ◽  
Water Flow ◽  
Removal Efficiency ◽  
Flow Rate ◽  
Test Protocol ◽  
Household Water ◽  
Medium Flow ◽  
Removal Efficiencies ◽  
Frequent Sampling

Radon is one of the contaminants that sometimes impair the water quality of wells, especially those drilled in bedrock. Domestic radon removal units based on aeration have been commercially available for more than ten years. In order to determine how effectively these units remove radon a new test protocol applying frequent sampling while letting 100 litres of water flow, was developed. This way, removal efficiencies can be more accurately calculated and possible malfunctions detected. Seven models of domestic aerators designed for removing radon from household water were tested. The aerators were based on diffused bubble aeration, spray aeration or jet aeration. The average removal efficiencies for 100 litres with a medium flow rate were 86–100% except for a unit that circulated the aerated water back to the well that had removal efficiency of 80% at the maximum. By conducting a questionnaire study usual problems related to the aeration units were localized and recommendations on maintenance and installation are given accordingly.

On the Influence of Fluctuating Flow Rate Upon the Performance and Behaviour of Isothermal Reacting Systems

1998 ◽  
Vol 63 (6) ◽  
pp. 881-898
Author(s):  
Otakar Trnka ◽  
Miloslav Hartman
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Fluidized Bed Reactor ◽  
Computational Techniques ◽  
Continuous Stirred Tank Reactor ◽  
Gas Flow Rate ◽  
Solid Reaction ◽  
Continuous Stirred Tank ◽  
And Performance ◽  
Reacting Systems

Three simple computational techniques are proposed and employed to demonstrate the effect of fluctuating flow rate of feed on the behaviour and performance of an isothermal, continuous stirred tank reactor (CSTR). A fluidized bed reactor (FBR), in which a non-catalytic gas-solid reaction occurs, is also considered. The influence of amplitude and frequency of gas flow rate fluctuations on reactant concentrations at the exit of the CSTR is shown in four different situations.

Treatment of Palm Oil Mill Effluent (POME) Supernatants Using Aerobic Attached–Growth System: Trickling Filter as a Case Study

2012 ◽  
Author(s):  
Ahmad Zuhairi Abdullah ◽  
Mohamad Hakimi Ibrahim ◽  
Mohd. Omar Ab. Kadir
Keyword(s):  
Palm Oil ◽  
Colloidal Particles ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Palm Oil Mill Effluent ◽  
Trickling Filter ◽  
Biomass Hydrolysis ◽  
Removal Efficiencies ◽  
Palm Oil Mill ◽  
Hydrolysis Of

Kertas kerja ini membincangkan tentang kecekapan penuras cucur dalam merawat supernatan kumbahan kilang kelapa sawit (POME). Supernatan POME diperoleh menerusi dua jenis perawatan. Dalam perawatan 1, pengendapan graviti digunakan untuk menyingkir pepejal boleh mendak. Perawatan 2 digunakan untuk menyingkir pepejal boleh mendak dan gumpalan partikal dengan menggunakan 350 ppm alum. Influen dialurkan secara titisan pada biojisim yang terlekat pada penyokong pepejal rawak PVC setinggi 1 m. Penuras cucur berupaya menyingkir lebih daripada 90.0% dari keperluan oksigen biologi (BOD) dan keperluan oksigen kimia (COD) di bawah 1 m3/m2–hari. Pada 2.53 m3/m2–hari, influen dengan Perawatan 1 menghasilkan kecekapan penyingkiran COD sebanyak 40.3%, berbanding 83.1% bila Perawatan 2 digunakan. Perkara ini berlaku berikutan penyingkiran bahan organik tak boleh resap semasa Perawatan 2. Kecekapan penyingkiran menurun dengan meningkatnya bebanan hidraulik kerana wujudnya kelemahan dalam hidrolisis bahan tak boleh resap kepada substratum larut. Dengan edaran semula (α=1), penyingkiran BOD dan COD yang lebih tinggi dicapai di bawah 7 m3/m2–hari. Pencapaian ini disebabkan oleh bebanan organik yang lebih rendah serta pergedaran semula enzim dan biojisim yang aktif kepada sistem. Perawatan 2 menghasilkan enap cemar yang lebih tinggi kerana penukaran substratum boleh larut kepada biojisim tak boleh larut. Hidrolisis bahan organik tak boleh resap didapati berlaku secara aktif pada bahagian atas penuras cucur sementara bahagian bawahnya cenderung mengoksidakan substratum organik. Kata kunci: POME, turas cucur, bahan organik bolehresap, penggumpalan, alir semula This paper discusses the efficiency of a trickling filter to treat Palm Oil Mill Effluent (POME) supernatants. POME supernatants were obtained via two treatments. In Treatment 1, gravity sedimentation was used to remove settleable solids. In Treatment 2, both settleable solids and colloidal particles were removed using 350 ppm of alum. The influents were allowed to trickle over biomass attached to 1 m high random PVC solid support. Below 1 m3/m2–day, the filter demonstrated Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) removal efficiencies of more than 90.0%. At 2.53 m3/m2–day, the influent with Treatment 1 gave a COD removal efficiency of 40.3%, but increased to 83.1% when the influent with Treatment 2 was used. This was ascribed to the removal of non–diffusible organics during Treatment 2. The removal efficiencies decreased with an increase in hydraulic loading due to limitations in the hydrolysis of non–diffusibles into soluble substrates. With recirculation (α=1), higher BOD and COD removals were achieved below 7.0 m3/m2–day, attributed to lower organic loading and the recycling of active enzyme and biomass to the system. The influent with Treatment 2 demonstrated higher sludge production due to higher conversion of soluble substrates into insoluble biomass. Hydrolysis of non–diffusible organics mainly took place at upper reaches of the filter column while lower reaches were involved in oxidizing the organic subtrates. Key words: POME, trickling filter, diffusible organic, coagulation, recirculation

scholarly journals Laser-Doppler Velocimetry Measurements Inside a Backward Curved Centrifugal Fan

2001 ◽  
Vol 7 (3) ◽  
pp. 173-181
Author(s):  
Tong-Miin Liou ◽  
Meng-Yu Chen
Keyword(s):  
Flow Rate ◽  
Turbulence Intensity ◽  
Laser Doppler Velocimetry ◽  
Reverse Flow ◽  
Flow Region ◽  
Design Flow ◽  
Laser Doppler ◽  
Centrifugal Fan ◽  
Doppler Velocimetry ◽  
Flow Rates

Laser-Doppler velocimetry (LDV) measurements are presented of relative mean velocity and turbulence intensity components inside the impeller passage of a centrifugal fan with twelve backward curved blades at design, under-design, and over-design flow rates. Additional LDV measurements were also performed at the volute outlet to examine the uniformity of the outlet flow for the three selected flow rates. Complementary flow visualization results in the tongue region are further presented. It is found that the number of characteristic flow regions and the average turbulence level increase with decreasing air flow rate. For the case of under-design flow rate, there are a through-flow region on the suction side, a reverse flow region on the pressure side, and a shear layer region in between. The corresponding average turbulence intensity is as high as 9.1% of blade tip velocity.

Hydraulic Design of Inlet Guide Vane and its Full Flow Passage Numerical Simulation on Centrifugal Pump

2014 ◽  
Author(s):  
Hucan Hou ◽  
Yongxue Zhang ◽  
Zhenlin Li ◽  
Xin Zhou ◽  
Zizhe Wang
Keyword(s):  
Centrifugal Pump ◽  
Flow Rate ◽  
Guide Vane ◽  
Hydraulic Performance ◽  
Design Flow ◽  
Inlet Guide Vane ◽  
Hydraulic Efficiency ◽  
Flow Passage ◽  
Setting Angle ◽  
Hydraulic Design

In order to effectively improve hydraulic performance of centrifugal pump on off-conditions, the hydraulic design of inlet guide vane (IGV) was completed by adopting two dimensional theory in-house code based on one kind of IS series of centrifugal pump, which can achieve pre-whirl regulation of centrifugal pump. During design process the trailing edge of vane is assumed as equal velocity moment condition, and the distribution of vane setting angle along meridional streamline is also given as a quartic function firstly, the camber line is then drawn by point-by-point integration method and thickened at both sides along circumferential direction. With local vortex dynamics diagnosis theory, the optimal improvement of vane space shape can be finished by adjusting the design parameters of vane setting angle distribution coefficient ap. The full flow passage numerical simulations of centrifugal pump with IGV device are completed to analyze the influence of pre-whirl regulation on hydraulic performance of centrifugal pump under various pre-whirl angles. The results show that the pre-whirl regulation can improve the hydraulic performance of centrifugal pump on off-conditions. Under the positive pre-whirl regulation conditions, the best efficient point shift to small flow rate zone, and under the negative pre-whirl regulation conditions it moves to large flow rate zone. Compared with the pump without IGV device at the same flow rate condition of 0.8Q (Q the design flow rate), the hydraulic efficiency of centrifugal pump with IGV device improves obviously and reaches up to 1.43%. Meanwhile compared with that installed with the straight vanes designed based on the traditional theory, the inner flow field of centrifugal pump with the designed vanes improves and the overall hydraulic efficiency of centrifugal pump is somewhat increased.

scholarly journals Application of Electrocoagulation Process for Dairy Wastewater Treatment

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Edris Bazrafshan ◽  
Hossein Moein ◽  
Ferdos Kord Mostafapour ◽  
Shima Nakhaie
Keyword(s):  
Reaction Time ◽  
Applied Voltage ◽  
Oxygen Demand ◽  
Dairy Wastewater ◽  
Operating Parameters ◽  
Pollution Load ◽  
Reliable Technique ◽  
Electrocoagulation Process ◽  
Aluminum Electrodes ◽  
Industry Wastewater

Dairy industry wastewater is characterized by high biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and other pollution load. The purpose of this study was to investigate the effects of the operating parameters such as applied voltage, number of electrodes, and reaction time on a real dairy wastewater in the electrocoagulation process. For this purpose, aluminum electrodes were used in the presence of potassium chloride as electrolytes. It has been shown that the removal efficiency of COD, BOD5, and TSS increased with increasing the applied voltage and the reaction time. The results indicate that electrocoagulation is efficient and able to achieve 98.84% COD removal, 97.95% BOD5removal, 97.75% TSS removal, and >99.9% bacterial indicators at 60 V during 60 min. The experiments demonstrated the effectiveness of electrocoagulation techniques for the treatment of dairy wastewaters. Finally, the results demonstrated the technical feasibility of electrocoagulation process using aluminum electrodes as a reliable technique for removal of pollutants from dairy wastewaters.

scholarly journals A Three-Dimensional Shock Loss Model Applied to an Aft-Swept, Transonic Compressor Rotor

1996 ◽  
Author(s):  
Steven L. Puterbaugh ◽  
William W. Copenhaver ◽  
Chunill Hah ◽  
Arthur J. Wennerstrom
Keyword(s):  
Flow Rate ◽  
Pressure Ratio ◽  
Three Dimensional ◽  
Numerical Results ◽  
Design Flow ◽  
Design System ◽  
Loss Model ◽  
Transonic Compressor ◽  
Compressor Rotor ◽  
Shock Loss

An analysis of the effectiveness of a three-dimensional shock loss model used in transonic compressor rotor design is presented. The model was used during the design of an aft-swept, transonic compressor rotor. The demonstrated performance of the swept rotor, in combination with numerical results, is used to determine the strengths and weaknesses of the model. The numerical results were obtained from a fully three-dimensional Navier-Stokes solver. The shock loss model was developed to account for the benefit gained with three-dimensional shock sweep. Comparisons with the experimental and numerical results demonstrated that shock loss reductions predicted by the model due to the swept shock induced by the swept leading edge of the rotor were exceeded. However, near the tip the loss model under-predicts the loss because the shock geometry assumed by the model remains swept in this region while the numerical results show a more normal shock orientation. The design methods and the demonstrated performance of the swept rotor is also presented. Comparisons are made between the design intent and measured performance parameters. The aft-swept rotor was designed using an inviscid axisymmetric streamline curvature design system utilizing arbitrary airfoil blading geometry. The design goal specific flow rate was 214.7 kg/sec/m2 (43.98 lbm/sec/ft2), the design pressure ratio goal was 2.042, and the predicted design point efficiency was 94.0. The rotor tip sped was 457.2 m/sec (1500 ft/sec). The design flow rate was achieved while the pressure ratio fell short by 0.07. Efficiency was 3 points below prediction, though at a very high 91 percent. At this operating condition the stall margin was 11 percent.

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