scholarly journals Strategies for recovering inhibition caused by phenolic compounds in a short-cut nitrogen removal reactor treating coal gasification wastewater

2015 ◽  
Vol 5 (4) ◽  
pp. 569-578 ◽  
Author(s):  
Qian Zhao ◽  
Hongjun Han ◽  
Fang Fang ◽  
Haifeng Zhuang ◽  
Dexin Wang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Phenolic Compounds ◽  
Nitrogen Removal ◽  
Coal Gasification ◽  
Activated Carbons ◽  
Powdered Activated Carbon ◽  
Nitrifying Bacteria ◽  
Quick Recovery ◽  
Coal Gasification Wastewater ◽  
Biological Nitrogen

Different strategies, including extension of hydraulic retention time (HRT), dilution, and addition of powdered activated carbon (PAC) and super-powdered activated carbon (S-PAC), were investigated for the quick recovery of nitrifying bacteria activity from the inhibition of coal gasification wastewater (CGW). A laboratory-scale short-cut biological nitrogen removal (SBNR) reactor treating CGW, achieving high levels (90%) of nitrogen removal, was used. After a shock of phenolic compounds (around 250 mg/L) and a failed performance, the results of the batch recovery tests indicated that the PAC and S-PAC addition were the best recovery strategies. In the SBNR reactor, the addition of 1 g/L PAC and S-PAC shortened the recovery time from the natural recovery of 32 days to 13 days and 10 days, respectively. Fluorescence in situ hybridization (FISH) assay and the adsorption isotherms revealed that activated carbons absorbed phenolic compounds, reducing the toxicity and allowing for the quick recovery of SBNRs treating CGW. S-PAC showed greater adsorption capacity for phenol than PAC.

scholarly journals Effect of powdered activated carbon technology on short-cut nitrogen removal for coal gasification wastewater

2013 ◽  
Vol 142 ◽  
pp. 179-185 ◽  
Author(s):  
Qian Zhao ◽  
Hongjun Han ◽  
Chunyan Xu ◽  
Haifeng Zhuang ◽  
Fang Fang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Nitrogen Removal ◽  
Coal Gasification ◽  
Powdered Activated Carbon ◽  
Coal Gasification Wastewater

Removal of nitrogen from coal gasification wastewater by nitrosofication and denitrosofication

1998 ◽  
Vol 38 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Junxin Liu ◽  
Weiguang Li ◽  
Xiuheng Wang ◽  
Hongyuan Liu ◽  
Baozhen Wang
Keyword(s):  
Nitrogen Removal ◽  
Coal Gasification ◽  
Oxygen Demand ◽  
Test Results ◽  
New Process ◽  
Scale Test ◽  
Coal Gasification Wastewater ◽  
Total Nitrogen Removal ◽  
Biological Nitrogen ◽  
Bench Scale Test

In this paper, a study of a new process with nitrosofication and denitrosofication for nitrogen removal from coal gasification wastewater is reported. In the process, fibrous carriers were packed in an anoxic tank and an aerobic tank for the attached growth of the denitrifying bacteria and Nitrobacter respectively, and the suspended growth activated sludge was used in an aerobic tank for the growth of Nitrosomonas. A bench scale test has been carried out on the process, and the test results showed that using the process, 25% of the oxygen demand and 40% of the carbon source demand can be saved, and the efficiency of total nitrogen removal can increase over 10% as compared with a traditional process for biological nitrogen removal.

Treatment of coal gasification wastewater by membrane bioreactor hybrid powdered activated carbon (MBR–PAC) system

Chemosphere ◽  
2014 ◽  
Vol 117 ◽  
pp. 753-759 ◽  
Author(s):  
Shengyong Jia ◽  
Hongjun Han ◽  
Baolin Hou ◽  
Haifeng Zhuang ◽  
Fang Fang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Membrane Bioreactor ◽  
Coal Gasification ◽  
Powdered Activated Carbon ◽  
Coal Gasification Wastewater

Membrane application to water purification process in Japan – development of hybrid membrane system

2000 ◽  
Vol 41 (10-11) ◽  
pp. 9-16 ◽  
Author(s):  
Y. Watanabe ◽  
K. Kimura ◽  
T. Suzuki
Keyword(s):  
Activated Carbon ◽  
Humic Substances ◽  
Water Purification ◽  
Activated Carbons ◽  
Membrane System ◽  
Hybrid Membrane ◽  
Powdered Activated Carbon ◽  
Nitrifying Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Membrane Process

This paper deals with two recent developments made by the authors about the hybrid membrane systems applicable to the water purification. The performance of a hybrid MF membrane system with circulating powdered activated carbon and condensed sludge has been studied using a pilot plant. The powdered activated carbon was intermittently dosed to the system for adsorbing mainly the humic substances. Manganese ions and ammonia nitrogen were biologically oxidized by the iron-oxidizing bacteria and ammonia oxidizing bacteria inhibiting the condensed sludge. In the hybrid MF membrane system, decreasing rate of the permeability was much less than that of a conventional MF membrane process. This may result from the reduced organic loading to the membrane due to the adsorption of humic substances onto the powdered activated carbons. A novel UF membrane process was also developed, where the nitrifying bacteria are fixed on the surface of the rotating disk membranes. With this membrane process, the simultaneous performance of the strict solid-liquid separation and the biological ammonia oxidation are possible. In order to increase the washing efficiency, a small quantity of the sponge particles were introduced into the membrane chamber and then the disk rotational speed was increased. This membrane washing method using sponge particles was so effective that the filtration resistance due to the accumulated cake was completely cancelled.

Nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process

2014 ◽  
Vol 26 (11) ◽  
pp. 2231-2239 ◽  
Author(s):  
Qian Zhao ◽  
Hongjun Han ◽  
Baolin Hou ◽  
Haifeng Zhuang ◽  
Shengyong Jia ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Nitrogen Removal ◽  
Coal Gasification ◽  
Removal Process ◽  
Coal Gasification Wastewater

Unsteady Modeling of Powdered Activated Carbon Deposition on Collection Electrode of a Lab-Scale Electrostatic Precipitator (ESP)

2012 ◽  
Author(s):  
Yasmin Khakpour ◽  
Herek L. Clack
Keyword(s):  
Activated Carbon ◽  
Particle Deposition ◽  
Electrostatic Precipitator ◽  
Activated Carbons ◽  
Collection Efficiency ◽  
Continuous Phase ◽  
Powdered Activated Carbon ◽  
Computational Domain ◽  
Discrete Phase Model ◽  
Discrete Phase

Particulate sampling in the flue gas at the Electrostatic Precipitator (ESP) outlet during injection of powdered activated carbons (PACs) has provided strong anecdotal evidence indicating that injected PACs can penetrate the ESP in significant concentrations. The low resistivity of PAC is consistent with poor collection efficiency in an ESP and lab-scale testing has revealed significantly different collection behavior of PAC in an ESP as compared to fly ash. The present study illustrates the use of a commercial CFD package — FLUENT — to investigate precipitation of powdered activated carbon (PAC) in the presence and absence of electric field. The computational domain is designed to represent a 2-D wire-plate ESP channel. The governing equations include those covering continuous phase transport, electric potential, air ionization, and particle charging. The particles are tracked using a Lagrangian Discrete Phase Model (DPM). In addition, a custom user-defined function (UDF) uses a deforming boundary condition and a prescribed critical particle velocity to account for particle deposition and dust-cake growth on the electrodes. The effect of Electrohydrodynamics (EHD) induced flow on the ESP collection efficiency under various flow and particle characteristics as well as different ESP configurations are illustrated.

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