Ammonium removal from groundwater using a zeolite permeable reactive barrier: a pilot-scale demonstration

2014 ◽  
Vol 70 (9) ◽  
pp. 1540-1547 ◽  
Author(s):  
Shengpin Li ◽  
Guoxin Huang ◽  
Xiangke Kong ◽  
Yingzhao Yang ◽  
Fei Liu ◽  
...  

In situ remediation of ammonium-contaminated groundwater is possible through a zeolite permeable reactive barrier (PRB); however, zeolite's finite sorption capacity limits the long-term field application of PRBs. In this paper, a pilot-scale PRB was designed to achieve sustainable use of zeolite in removing ammonium (NH4+-N) through sequential nitrification, adsorption, and denitrification. An oxygen-releasing compound was added to ensure aerobic conditions in the upper layers of the PRB where NH4+-N was microbially oxidized to nitrate. Any remaining NH4+-N was removed abiotically in the zeolite layer. Under lower redox conditions, nitrate formed during nitrification was removed by denitrifying bacteria colonizing the zeolite. During the long-term operation (328 days), more than 90% of NH4+-N was consistently removed, and approximately 40% of the influent NH4+-N was oxidized to nitrate. As much as 60% of the nitrate formed in the PRB was reduced in the zeolite layer after 300 days of operation. Removal of NH4+-N from groundwater using a zeolite PRB through bacterial nitrification and abiotic adsorption is a promising approach. The zeolite PRB has the advantage of achieving sustainable use of zeolite and immediate NH4+-N removal.

2019 ◽  
Vol 136 ◽  
pp. 06021
Author(s):  
Qianfeng He ◽  
Shihui Si ◽  
Jun Yang ◽  
Xiaoyu Tu

As a new in-situ remediation of groundwater, compared with the traditional “pump and treat” technology, the permeable reactive barrier (PRB) has the advantages of low cost, no external power, the small disturbance to groundwater, small secondary pollution and long-term operation, this paper introduces the basic concept of PRB, technical principle, structure type, the principle of active materials selection and mechanisms of remediation, design and installation factors, it provides ideas for further research and application of PRB technology in groundwater remediation projects in China.


Geophysics ◽  
2003 ◽  
Vol 68 (3) ◽  
pp. 911-921 ◽  
Author(s):  
Lee Slater ◽  
Andrew Binley

The permeable reactive barrier (PRB) is a promising in‐situ technology for treatment of hydrocarbon‐contaminated groundwater. A PRB is typically composed of granular iron which degrades chlorinated organics into potentially nontoxic dehalogenated organic compounds and inorganic chloride. Geophysical methods may assist assessment of in‐situ barrier integrity and evaluation of long‐term barrier performance. The highly conductive granular iron makes the PRB an excellent target for conductivity imaging methods. In addition, electrochemical storage of charge at the iron–solution interface generates an impedance that decreases with frequency. The PRB is thus a potential induced polarization (IP) target. Surface and cross‐borehole electrical imaging (conductivity and IP) was conducted at a PRB installed at the U.S. Department of Energy's Kansas City plant. Poor signal strength (25% of measurements exceeding 8% reciprocal error) and insensitivity at depth, which results from current channeling in the highly conductive iron, limited surface imaging. Crosshole 2D and 3D electrical measurements were highly effective at defining an accurate, approximately 0.3‐m resolution, cross‐sectional image of the barrier in‐situ. Both the conductivity and IP images reveal the barrier geometry. Crosshole images obtained for seven panels along the barrier suggest variability in iron emplacement along the installation. On five panels the PRB structure is imaged as a conductive feature exceeding 1 S/m. However, on two panels the conductivity in the assumed vicinity of the PRB is less than 1 S/m. The images also suggest variability in the integrity of the contact between the PRB and bedrock. This noninvasive, in‐situ evaluation of barrier geometry using conductivity/IP has broad implications for the long‐term monitoring of PRB performance as a method of hydrocarbon removal.


2002 ◽  
Vol 45 (10) ◽  
pp. 49-54 ◽  
Author(s):  
R. El Mamouni ◽  
R. Jacquet ◽  
P. Gerin ◽  
S.N. Agathos

Laboratory- and pilot-scale studies were conducted in order to adjust and optimize the in-situ conditions for bioremediation of a soil contaminated with trichlororethene (TCE) and nickel. Results from laboratory studies showed that the indigenous microorganisms of the soil were limited by the type of electron donor. A better TCE dechlorination was obtained when the electron donor was composed of a mixture of methanol and lactate, as compared to that with methanol alone. Addition of up to 10 mM of sulphate as external electron acceptor (in combination with TCE) and with a mixture of methanol and lactate as electron donor had no significant effect on the TCE reducing activity of indigenous microorganisms of the soil, while higher concentrations (15 and 20 mM) yielded a lower dechlorination. Long term operation of a large pilot-scale soil reactor demonstrated the feasibility of a single-process in situ soil remediation. Results showed that, on one hand, TCE was progressively and stepwise reduced to cis-dichloroethene (DCE), vinyl chloride (VC) and finally to ethene, using only the indigenous microorganisms of the soil. On the other hand, stimulating the activity of sulphate-reducing bacteria of the soil with the addition of sulphate as electron acceptor was efficient in precipitating nickel as nickel sulphide.


Author(s):  
Arndt Wiessner ◽  
Jochen A. Müller ◽  
Peter Kuschk ◽  
Uwe Kappelmeyer ◽  
Matthias Kästner ◽  
...  

The large scale of the contamination by the former carbo-chemical industry in Germany requires new and often interdisciplinary approaches for performing an economically sustainable remediation. For example, a highly toxic and dark-colored phenolic wastewater from a lignite pyrolysis factory was filled into a former open-cast pit, forming a large wastewater disposal pond. This caused an extensive environmental pollution, calling for an ecologically and economically acceptable strategy for remediation. Laboratory-scale investigations and pilot-scale tests were carried out. The result was the development of a strategy for an implementation of full-scale enhanced in situ natural attenuation on the basis of separate habitats in a meromictic pond. Long-term monitoring of the chemical and biological dynamics of the pond demonstrates the metamorphosis of a former highly polluted industrial waste deposition into a nature-integrated ecosystem with reduced danger for the environment, and confirmed the strategy for the chosen remediation management.


Sign in / Sign up

Export Citation Format

Share Document