Electro-thermal treatment optimization of high concentration ammonia nitrogen by gaseous oxidation in liquid phase (GOLP)

2011 ◽  
Vol 63 (12) ◽  
pp. 2896-2901 ◽  
Author(s):  
Li Mei Cao ◽  
Ji Yang ◽  
Jin Ping Jia
Keyword(s):  
Liquid Phase ◽  
Crystalline Silicon ◽  
Ammonia Nitrogen ◽  
Ammonia Removal ◽  
Alkaline Ph ◽  
High Concentration ◽  
Treatment Optimization ◽  
Ammonia Conversion ◽  
Ammonia Degradation ◽  
Future Reference

This study is focused on optimizing the treatment parameters for high concentration ammonia using gaseous oxidation in liquid phase (GOLP). The conversion of ammonia was achieved electro-thermally over mono-crystalline silicon supported CoOx catalyst. The experimental results demonstrated that factors including the co-anions, pH of the solutions, air flowrate and the current showed apparent influences on the ammonia removal. The higher the Cl− concentration and/or current, the better the efficiency of ammonia degradation. The increase of the air flowrate would increase the ammonia removal accordingly. And it was also observed that the pH declined during the ammonia conversion, and the neutral and alkaline pH were beneficial to the ammonia removal. The preliminary cost analysis based on lab data was also provided for future reference.

Removal of Ammonia Nitrogen from Landfill Leachate by Ultrasound/Ultraviolet Process

2013 ◽  
Vol 448-453 ◽  
pp. 536-539
Author(s):  
Bin Liu ◽  
Xu Ya Peng ◽  
Qi Tian ◽  
Hua Zhao
Keyword(s):  
Removal Efficiency ◽  
Nitrogen Removal ◽  
Landfill Leachate ◽  
Nitrogen Concentration ◽  
Ammonia Nitrogen ◽  
Aeration Rate ◽  
Ammonia Removal ◽  
Ultrasonic Power ◽  
High Concentration ◽  
Leachate Treatment

Landfill leachate treatment is a major problem to be solved in the field of environmental protection, and ammonia nitrogen is one of the major pollutants in landfill leachate, whose processing technology needs further improvement. In this paper, ultrasound/ultraviolet co-oxidation technology was directly applied to the treatment of high concentration landfill leachate without the pretreatment operations of dilution, filter, and adjusting the pH conditions. The results showed that: ultrasonic and ultraviolet had certain effects on the ammonia nitrogen removal, and the ammonia nitrogen removing effects became better when the ultrasonic power was greater, or the ultraviolet wavelength was shorter. When the ultrasonic power was 100 W, the ammonia nitrogen removal efficiency was 25.2%, and the UV of 254 nm could decompose 20.2% of the ammonia nitrogen in landfill leathate. In the condition of aeration, ultrasonic and ultraviolet had good synergistic effect on leachate ammonia nitrogen treatment. When the ultrasonic power was 100 W, UV wavelength was 254 nm, and the aeration rate was 150 L/h, the ammonia removal efficiency of high concentration leachate (ammonia nitrogen concentration of 1800 mg/L) reached 98.5% after 6 hours. The paper's research results provide a useful reference for the removal of landfill leachate ammonia nitrogen.

The circulating floating bed reactor: effect of particle size distribution of the carrier on ammonia conversion

2000 ◽  
Vol 41 (4-5) ◽  
pp. 393-400 ◽  
Author(s):  
J.M. Garrido-Fernandez ◽  
R. Méndez ◽  
J.M. Lema ◽  
V. Lazarova
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
G Protein ◽  
Biomass Concentration ◽  
Biomass Accumulation ◽  
Ammonia Removal ◽  
Operating Conditions ◽  
Nitrification Rate ◽  
Ammonia Conversion ◽  
Biomass Activity

Three Circulating Floating Bed Reactors (CFBR) R1, R2 and R3 with 20% v/v of a plastic carrier with different size distribution were operated to study the effect of the particles size of the carrier on biomass accumulation and nitrification performance. Operating conditions were similar in the three systems: ammonia concentrations around 50 mg-N–NH4+/ L, ammonia loading rates up to 1.2 kg N–NH4+/m3·d and temperatures between 14 and 27°C. Accumulation of nitrite was observed until day 65th. This w as result both of the inhibition of nitrite oxidation by free ammonia until day 20th and the insignificant accumulation of a biomass with low nitrite oxidising capacity between days 20 and 65th. Ammonia conversion rate and removal efficiency were higher in the reactor with lower particle size, R3 (nitrification rate of 1.1 kg N–NH4+/m3·d and ammonia removal of 97% at 16°C), than in R2 or R1 (nitrification rate of 1.0 kg N–NH4+/m3·d and ammonia removal of 90% at 16°C). The better efficiency in R3 was obtained as a result of the higher specific surface of the biofilm developed. Biomass activity was similar in the three reactors (2.2 and 1.12 g N/g protein · d at 30 and 15°C, respectively). Both the biomass evolution with time and biomass retention in the systems was practically not influenced by the size of particle. Biomass concentration of 1.2 g protein/L was retained in the carrier and up to 20% of the newly produced biomass was retained in the CFBRs.

Diffusion In Insect Wing Muscle, The Most Active Tissue Known

1964 ◽  
Vol 41 (2) ◽  
pp. 229-256 ◽  
Author(s):  
TORKEL WEIS-FOGH
Keyword(s):  
Liquid Phase ◽  
Safety Factor ◽  
Metabolic Rates ◽  
High Concentration ◽  
Tracheal System ◽  
Insect Wing ◽  
Main Site ◽  
Normal Diffusion ◽  
Large Fibre ◽  
Very High

1. The tracheal system of insect wing muscle is so dense that between 10-1 and 10-3 of any cut area is occupied by air tubes. In most cases, air tube diffusion of O2 and CO2 through the muscle is therefore several thousand times quicker than diffusion in the liquid phase. 2. In large insects the primary tracheal supply must be strongly ventilated while diffusion is sufficient in the remaining part of the air tubes, even at the highest metabolic rates encountered in any insect. 3. The tracheoles represent the main site of exchange between the gaseous and the liquid phase while the tracheae are of little significance in this respect. The fibres cannot exceed about 20 µ in diameter unless the tracheoles indent the surface and become ‘internal’. 4. Muscular pumping of air and blood due to shortening is of little importance for the exchange of gases but of major importance for the supply with fuel for combustion. However, the large fibre diameters and the tidal nature of the pumping necessitates a very high concentration of fuel in the haemolymph. The high concentration of trehalose in insect blood is considered to be an essential adaptation to flapping flight. 5. The transport by diffusion of O2 and CO2 was followed in detail in a number of concrete examples in the gaseous as well as in the liquid phase. Within a safety factor of 2-3, the rate of transport was always found to be adequate. There is no reason to suggest other mechanisms than a simple, normal diffusion.

Research on Nitrogen Removal Performance of Leachate Treatment of WSIP Reactor

2011 ◽  
Vol 55-57 ◽  
pp. 789-795
Author(s):  
Xiu Ju Duan ◽  
Qiang He ◽  
Ya Li Liu
Keyword(s):  
Nitrogen Removal ◽  
Biological Treatment ◽  
Orthogonal Experiment ◽  
Ammonia Nitrogen ◽  
Ammonia Removal ◽  
Leachate Treatment ◽  
Treatment Performance ◽  
Biomass Retention ◽  
Nitrification And Denitrification

This thesis put forward the treatment concept of “without Biomass Retention Sequential Batch Intensified Pretreatment (WSIP)” in leachate treatment, for sake of improving performance of nitrogen removal, optimizing excess water’s nutritional ratio and benefitting the follow-up aerobic biological treatment. Based on orthogonal experiment of WSIP Reactor’s leachate treatment performance, Conclusions can be drew: the removal performance of ammonia nitrogen and TN is higher of WSIP, in which short-cut nitrification and denitrification can be realized; HRT, DO and sequential period are remarkable factors of ammonia removal performance, TN removal performance and realization of short-cut nitrification and denitrification; In normal temperature, the most perfect functional parameter of WSIP Reactor is: HRT=4d, DO=0.75mg/L and sequential period is 6h.

(Invited) Electrochemical Liquid Phase Epitaxy of Crystalline Silicon Films

2021 ◽  
Vol MA2021-01 (24) ◽  
pp. 930-930
Author(s):  
Stephen Maldonado ◽  
Nathanael Downes
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Epitaxy ◽  
Crystalline Silicon ◽  
Silicon Films

scholarly journals The comparison of efficiency of Fenton and photo-Fenton treatment of stabilised landfill leachate / Porównanie efektywności oczyszczania odcieków z ustabilizowanego składowiska odpadów komunalnych w procesie Fentona i foto-Fentona

2015 ◽  
Vol 26 (3) ◽  
pp. 49-53 ◽  
Author(s):  
Anna Kwarciak-Kozłowska ◽  
Aleksandra Krzywicka
Keyword(s):  
Landfill Leachate ◽  
Fenton Reaction ◽  
Ferrous Sulphate ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Ammonia Removal ◽  
Mass Ratio ◽  
Leachate Treatment ◽  
Initial Ph ◽  
Removal Efficiencies

Abstract The goal of this article was to compare the efficiency of Fenton and photo-Fenton reaction used for stabilised landfill leachate treatment. The mass ratio of COD:H2O2 was fixed to 1:2 for every stages. The dose of reagents (ferrous sulphate/hydrogen peroxide) was different and ranged from 0.1 to 0.5. To determine the efficiency of treatment, the BOD (biochemical oxygen demand COD (chemical oxygen demand), TOC (total organic carbon) , ammonia nitrogen and BOD/COD ratio was measured. The experiment was carried out under the following conditions: temperature was 25ºC, the initial pH was adjusted to 3.0. Every processes were lasting 60 minutes. The most appropriate dose of reagents was 0.25 (Fe2+/H2O2). It was found that the application of UV contributed to increase of COD, TOC and ammonia removal efficiencies by an average of 14%.

Biological treatment of ammonia gas at high loading

2004 ◽  
Vol 50 (4) ◽  
pp. 283-290 ◽  
Author(s):  
T. Kanagawa ◽  
H.W. Qi ◽  
T. Okubo ◽  
N. Tokura
Keyword(s):  
Removal Rate ◽  
Space Velocity ◽  
Packed Bed ◽  
Porous Ceramics ◽  
Ammonia Removal ◽  
Ammonium Ion ◽  
Nitrifying Bacteria ◽  
High Concentration ◽  
Ammonia Gas ◽  
Cylinder Diameter

The exhaust gas from compost processing plants contains a large amount of ammonia. To treat ammonia gas at high loads, bench-scale experiments were carried out. First, nitrifying bacteria were enriched from soil and immobilized on porous ceramics. The ceramics were packed in an acrylic cylinder (diameter, 100 mm; packed height, 190 mm) and ammonia gas was introduced to the top of the cylinder. The concentration and flow rate of ammonia gas were gradually increased and finally 85 ppm was introduced at a space velocity of 800 h-1 (empty bed residence time (EBRT), 4.5 sec). The ammonia load was 1.0 kg N/m3 day-1. The exhaust contained 1.5-2 ppm of ammonia. Then the packed ceramics were transferred to another acrylic cylinder (diameter, 50 mm; packed height, 800 mm). A high concentration of ammonia gas (1,000 ppm) was introduced at a space velocity of 96 h-1 (ammonia loading, 1.44 kg N/m3 day-1; EBRT, 37.5 sec). The exhaust contained 2 ppm of ammonia (removal rate, 99.8%). The packed bed was washed with water intermittently or continuously, and the wastewater from the cylinder contained a large amount of ammonium and nitrate ions of at a 1:1 ratio. Stoichiometric analysis showed that half of the introduced ammonia was oxidized to nitrate, and the rest was converted to ammonium ion. Thus, ammonia gas was effectively treated at a high load by biofiltration with nitrifying bacteria.

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