Study on the Influence of C/N Ratio on Denitrification Efficiency in CRI System

2012 ◽  
Vol 599 ◽  
pp. 326-330
Author(s):  
Jun Min Chen ◽  
Zhen Hua Sheng
Keyword(s):  
Removal Efficiency ◽  
Soil Column ◽  
Experimental Results ◽  
Artificial Soil ◽  
National Standard ◽  
Feeding Mode ◽  
Feeding Modes ◽  
Starting Point ◽  
Anaerobic Zone ◽  
Denitrification Process

Abstract. The TN removal efficiency is very low and the TN concentration of effluent can not meet the national standard of GB18918-2002 in the CRI system. In order to increasingly improve the denitrification efficiency of the CRI system, the artificial soil column is used to simulate the CRI system with 4 kinds of wastewater step-feeding modes. A series of comparative experiments are carried out, and the experimental results show that the TN removal efficiency of the CRI system is controlled by the denitrification process, and the denitrification process takes place mainly in the 900-1400mm zone of the artificial soil column; with the step-feeding mode, the C/N ratios of effluent from the 900-1400mm zone increase obviously in the CRI system, and in the case 4, the C/N ratios of effluent from the 900-1400mm zone are about 2, which is the closest to the optimal C/N ratio of the denitrification process; the best wastewater feeding mode of the CRI system is that the wastewater is pumped into the system from the infiltration media surface and the starting point of the anaerobic zone at the same time, with the influent amount ratio of 2:1.

Experimental Study on the Optimal Thickness of Infiltration Media of the CRI System

2011 ◽  
Vol 415-417 ◽  
pp. 1703-1707
Author(s):  
Jun Min Chen ◽  
Xiao Lin Yao
Keyword(s):  
Experimental Study ◽  
Removal Efficiency ◽  
Significant Influence ◽  
Soil Column ◽  
Experimental Results ◽  
Artificial Soil ◽  
Optimal Thickness ◽  
Effluent Quality ◽  
Anaerobic Zone

Abstract. In order to investigate the optimal thickness of infiltration media in the Constructed Rapid Infiltration System, the artificial soil column is used to simulate the Constructed Rapid Infiltration System, and the CODCr, NH3-N and TN concentrations of the effluent from all the sampling sites are monitored. The experimental results and analysis show that the thickness of infiltration media exerts a significant influence on the CODCr, NH3-N and TN concentration and removal efficiency of the effluent; the CODCr, NH3-N and TN are mainly removed in the 0-1800mm zone of the artificial soil column; the total CODCr removal efficiency increases, as the thickness of infiltration media increases, but the CODCr removal efficiency in the 1800-2200mm zone is very low; the NH3-N and TN removal efficiency reaches the maximum where the thickness of infiltration media is 1800mm; the NH3-N and TN concentration of the effluent from 1800-2200mm zone dose not decrease, but increase 5-8%, due to the assimilation denitrification and amemoniation reaction on the end of the anaerobic zone; in consideration of the effluent quality, efficient biodegradation zone, construction investment, etc. the optimal thickness of infiltration media in CRI system should be 1800mm.

Comparative Experiment Study on the Total Phosphorus Removal Efficiency of Different Infiltration Media Combinations in the CRI System

2011 ◽  
Vol 415-417 ◽  
pp. 1735-1739 ◽  
Author(s):  
Jun Min Chen
Keyword(s):  
Adsorption Capacity ◽  
Removal Efficiency ◽  
Total Phosphorus ◽  
Phosphorus Removal ◽  
Sponge Iron ◽  
Experimental Results ◽  
National Standard ◽  
Phosphorus Adsorption ◽  
New Type ◽  
Better Than

The total phosphorus removal efficiency is very low and the TP concentration of the effluent can not reach the national standard of GB18918-2002 in CRI system. In order to solve these problems, a series of comparative experiments on phosphorus adsorption capacity of 5 kinds of special infiltration media are carried out. And then another series of comparative experiments on the total phosphorus removal efficiency of 4 kinds of infiltration media combinations are also conducted, the experimental results show that the phosphorus adsorption capacity of sponge iron is the best one among the special infiltration media selected；the phosphorus removal efficiency of the infiltration media including 1/6 sponge iron is much better than the infiltration media including only sand; and the phosphorus removal efficiency of the infiltration media combination with sponge iron homogeneously mixed with sand, is better than the infiltration media combination with the same weight of sponge iron concentrated. The experimental results will help to explore the development of the new type composite infiltration media of the CRI System.

CARBONATION INDUCED CORROSION ANALYSIS OF REINFORCED CONCRETE STRUCTURES BASED ON FULL PROBABILISTIC APPROACH – AN INDONESIAN CASE STUDY

2018 ◽  
Vol 4 (1) ◽  
pp. 165
Author(s):  
Herry Prabowo ◽  
Mochamad Hilmy
Keyword(s):  
Service Life ◽  
Probabilistic Approach ◽  
Concrete Structures ◽  
Weather Condition ◽  
Analysis Data ◽  
National Standard ◽  
Concrete Carbonation ◽  
Durability Design ◽  
Starting Point ◽  
Real Performance

The assessment of the service life of concrete structures using the durability design approach is widely accepted nowadays. It is really encouraged that a simulation model can resemble the real performance of concrete during the service life. This paper investigates the concrete carbonation through probabilistic analysis. Data regarding Indonesian construction practice were taken from Indonesian National Standard (SNI). Meanwhile, data related to Indonesian weather condition for instance humidity and temperature are taken from local Meteorological, Climatological, and Geophysical Agency from 2004 until 2016. Hopefully the results can be a starting point for durability of concrete research in Indonesia.

Optimal operations for groundwater denitrification of drinking water using heterotrophic biological denitrification process

2006 ◽  
Vol 6 (2) ◽  
pp. 125-130
Author(s):  
C.-H. Hung ◽  
K.-H. Tsai ◽  
Y.-K. Su ◽  
C.-M. Liang ◽  
M.-H. Su ◽  
...  
Keyword(s):  
Drinking Water ◽  
Removal Efficiency ◽  
Nitrate Removal ◽  
Drinking Water Treatment ◽  
Nitrate Content ◽  
Source Water ◽  
Nitrogen Gas ◽  
Negative Effect ◽  
Denitrification Process ◽  
Heterotrophic Denitrification

Due to the extensive application of artificial nitrogen-based fertilizers on land, groundwater from the central part of Taiwan faces problems of increasing concentrations of nitrate, which were measured to be well above 30 mg/L all year round. For meeting the 10 mg/L nitrate standard, optimal operations for a heterotrophic denitrification pilot plant designed for drinking water treatment was investigated. Ethanol and phosphate were added for bacteria growing on anthracite to convert nitrate to nitrogen gas. Results showed that presence of high dissolved oxygen (around 4 mg/L) in the source water did not have a significantly negative effect on nitrogen removal. When operated under a C/N ratio of 1.88, which was recommended in the literature, nitrate removal efficiency was measured to be around 70%, sometimes up to 90%. However, the reactor often underwent severe clogging problems. When operated under C/N ratio of 1.0, denitrification efficiency decreased significantly to 30%. Finally, when operated under C/N ratio of 1.5, the nitrate content of the influent was almost completely reduced at the first one-third part of the bioreactor with an overall removal efficiency of 89–91%. Another advantage for operating with a C/N ratio of 1.5 is that only one-third of the biosolids was produced compared to a C/N value of 1.88.

The Efficiency of Natural and Electrokinetic Enhanced Migration of Pb in Aquifer

2012 ◽  
Vol 253-255 ◽  
pp. 1098-1101
Author(s):  
Hong Tao Hu
Keyword(s):  
Heavy Metal ◽  
Removal Efficiency ◽  
Experimental Results ◽  
Contaminated Groundwater ◽  
Voltage Gradient ◽  
Migration Method ◽  
Variation Rule

The natural and electrokinetic enhanced migration method was studied by the experiments in groundwater contaminated by heavy metal Pb in this work. The experimental results showed that the variation rule of Pb reflected that its migration was weak and the removal efficiency was only 9.30% near the anode in the natural seepage condition, but under the enhanced migration and remediation function, the pollutants could be enriched and removed faster, thus the removal efficiency of Pb was 46.72% near the anode at the end of experiment when the experimental voltage gradient was 0.28V/cm, which made known that this electrokinetic enhanced migration of Pb in contaminated groundwater was more effective method than that of natural seepage migration and enhanced the removal of contaminant in aquifer.

Comparison between slag refining processes for B removal with metallurgical grade silicon and Si–Sn alloy

2018 ◽  
Vol 115 (3) ◽  
pp. 312 ◽  
Author(s):  
Rowaid Al-khazraji ◽  
Yaqiong Li ◽  
Lifeng Zhang
Keyword(s):  
Removal Efficiency ◽  
Acid Leaching ◽  
Experimental Results ◽  
Mass Ratio ◽  
Metallurgical Grade Silicon ◽  
Clear Effect ◽  
Slag Refining ◽  
Before And After ◽  
Grade Silicon ◽  
Refining Processes

Boron (B) removal by slag refining using CaO–SiO2–CaCl2 was investigated in metallurgical-grade silicon (MG-Si) and 75 wt% Si–Sn alloy. Experiments were conducted at 1500 °C for 15 min. The microstructure was characterized before and after refining. The effects of acid leaching, basicity, and slag/Si mass ratio on B removal were investigated. Experimental results showed that acid leaching had no effect on B removal from MG-Si but had a clear effect on the refined Si–Sn alloy after slag refining. The final B concentration was highly affected by the CaO/SiO2 mass ratio with minimum value, where the content of B was reduced from 18.36 ppmw to 5.5 ppmw at the CaO/SiO2 = 1.2 for MG-Si slag refining and from 18.36 ppmw to 3.7 ppmw at CaO/SiO2 = 1.5 for 75 wt% Si–Sn alloy. Increasing the slag mass ratio by 2:1 mass ratio also increased B removal efficiency by approximately 15–20% more than an increase by 1:1.

scholarly journals Detection and Analysis of LED Display System in Large Stadiums

2018 ◽  
pp. 51-57
Author(s):  
Xiaodong YI ◽  
Min ZHOU
Keyword(s):  
Connected Domain ◽  
Experimental Results ◽  
National Standard ◽  
Flat Panel Display ◽  
Display System ◽  
Flat Panel ◽  
Light Point ◽  
Scanning Line ◽  
Led Display System ◽  
Adjustment Scheme

As the mainstream products of flat panel display, LED screen is becoming more and more popular, which has been widely used in the display system of large gymnasium. The detection of LED display system in large stadium is analyzed. Based on the large LED display in Jingzhou stadium, the qualification of LED display system after installation is tested. A scanning line seed filling algorithm is proposed and used to collect the gray value in the connected domain of the lamp and obtain the average gray value of the light point, so that the LED display system of the large gymnasium is detected. The experimental results show that a reasonable LED display and adjustment scheme can ensure the installation of LED display system in large gymnasium in line with the requirements of the national standard.

Analytical Model for the Deformation of Viscoelastic Non-Newtonian Drops Undergoing Secondary Atomization

2016 ◽  
Author(s):  
Sharon E. Snyder ◽  
Varun Kulkarni ◽  
Paul E. Sojka
Keyword(s):  
Analytical Model ◽  
Xanthan Gum ◽  
Experimental Results ◽  
Analytical Models ◽  
Drop Diameter ◽  
Droplet Deformation ◽  
Secondary Atomization ◽  
Starting Point ◽  
Breakup Model ◽  
Xanthan Gum Solution

While there is no single analytical model that accurately predicts all stages and modes of secondary atomization, many groups have developed models that predict deformation and oscillation of a single, isolated drop. The TAB (Taylor Analogy Breakup) model was chosen for this investigation, mainly due to its widespread use by Liu and Reitz [1], Hwang et al. [2], Tanner [3], and Lee and Reitz [4], among others. Since the TAB model is also the foundation for many other analytical models, it will also be used here as a starting point for the development of a viscoelastic non-Newtonian model to predict droplet deformed radii, droplet deformation time, and velocity at deformation time for viscoelastic xanthan gum - DI water solutions. Three additional improvements are made to this viscoelastic TAB model: the first is a change to a TAB coefficient; the second to the equation for the drag coefficient, and the third modification is to the breakup criterion. This model uses Carreau rheology and Zimm relaxation time. Non-dimensional drop diameter and initiation times are plotted against We; model results are compared to experimental results for a range of xanthan gum solution concentrations. Results show fair agreement between experimental results and model results for non-dimensional drop diameter, with the best match at low XG concentration and low-to-medium We (10–30). It was also noted that increased viscoelasticity seems to increase this drop diameter. Good agreement between experimental data and model results has been seen for initiation time, with increased viscoelasticity increasing this parameter as well.

Linear Two-Port Model of an Active Thermoplastic Composite Structure

2013 ◽  
Author(s):  
Anja Winkler ◽  
Uwe Marschner ◽  
Eric Starke ◽  
Niels Modler ◽  
Wolf-Joachim Fischer ◽  
...  
Keyword(s):  
Composite Structure ◽  
Manufacturing Process ◽  
Composite Structures ◽  
Matrix Material ◽  
Manufacturing Technology ◽  
Experimental Results ◽  
Thermoplastic Composite ◽  
Starting Point ◽  
Modal Behavior ◽  
Active Composite

This paper describes new active composite structures based on thermoplastic matrices which contain material homogeneous embedded piezoceramic modules. Starting point is the development of novel thermoplastic compatible piezoceramic modules, so called TPMs. By the utilization of the same matrix material for the composite structure and for the TPM carrier films, these modules afford an opportunity to become directly embedded into the component during its manufacturing process. In this context, the manufacturing technology of the TPMs and of the active composite structure is presented. Furthermore, selected test samples are investigated concerning their modal behavior. Based on the determined characteristics a linear two-port model is used for the reproduction of the experimental results.

scholarly journals Effective Removal of Fluoride onto Metal Ions Loaded Orange Waste

2012 ◽  
Vol 27 ◽  
pp. 61-66 ◽  
Author(s):  
Kedar Nath Ghimire
Keyword(s):  
Metal Ions ◽  
Removal Efficiency ◽  
Orange Juice ◽  
Experimental Results ◽  
Fluoride Removal ◽  
Acidic Ph ◽  
Neutral Ph ◽  
Effective Removal ◽  
Orange Waste ◽  
Ph Range

Removal of fluoride is investigated onto several metal ions loaded phosphorylated orange juice residue and commercially available alumina. The experimental results revealed that cerium (IV) loaded phosphorylated orange waste indicated excellent fluoride removal efficiency at acidic pH range and while that lanthanum loaded at neutral pH range. Both the metal loaded adsorbents are found superior to the commercially available activated alumina.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6660 J. Nepal Chem. Soc., Vol. 27, 2011 61-66 

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