Nitrification processes in scrubbing liquid of an exhaust air treatment system of a large-scale pig housing facility

2011 ◽  
Vol 64 (10) ◽  
pp. 2009-2015 ◽  
Author(s):  
J. Haneke ◽  
V. Siemers ◽  
H. F. A. Van den Weghe

The use of multi-staged exhaust air treatment systems is an effective method of substantially reducing the emission of ammonia, dust particles and odorous substances. Wet filter walls are able to absorb large amounts of ammonia when scrubbing fluid containing sulphuric acid is used. In addition, due to their large surface areas and the permanent supply of oxygen and nutrients, wet filter walls provide a basis for the development of biofilms containing nitrogen-converting bacteria. Cyclic nitrification processes could be observed in a two-stage exhaust air treatment system, which had been converted to function as a regulated process control system (elutriation at κ = 20 mS cm−1; pH 6.5–6.8). With this system, the sulphuric acid requirement was periodically reduced every 6–8 weeks to less than 1 kg H2SO4 per fattening place and year. There was an increased formation of nitrous oxide gas during nitrification after the wet filter stage. Electron-microscopic images of the biofilm growing on the wet filter wall showed aggregates of possible ammonium-oxidising and nitrite-oxidising bacteria.

2010 ◽  
Vol 62 (7) ◽  
pp. 1551-1559 ◽  
Author(s):  
J. Haneke ◽  
N. M. Lee ◽  
T. W. Gaul ◽  
H. F. A. Van den Weghe

Exhaust air treatment has gained importance as an essential factor in intensive livestock areas due to the rising emissions in the environment. Wet filter walls of multi-stage exhaust air treatment systems precipitate gaseous ammonia and dust particles from exhaust air in washing water. Microbial communities in the biomass developed in the washing water of five large-scale exhaust air treatment units of pig housing facilities, were investigated by fluorescence in situ hybridization (FISH) and 16S rDNA sequence analyses. No “standard” nitrifying bacteria were found in the washing water. Instead mainly α-Proteobacteria, aggregating β- and χ-Proteobacteria, a large number of Actinobacteria, as well as individual Planctomycetales and Crenarchaeota were detected after more than twelve months' operation. The main Proteobacteria species present were affiliated to the families Alcaligenaceae, Comamonadaceae and Xanthomonadaceae. Furthermore, we investigated the consumption of inorganic nitrogen compounds in the washing water of one exhaust air treatment unit during a fattening period with and without pH control. Maintaining the pH at 6.0 resulted in a ca. fivefold higher ammonium concentration and a ca. fourfold lower concentration of oxidized nitrogen compounds after the fattening period was finished.


2019 ◽  
Vol 39 (4) ◽  
Author(s):  
Asma Naseem ◽  
Mohammad Sazzad Khan ◽  
Hashim Ali ◽  
Irshad Ahmad ◽  
Mohamad Aman Jairajpuri

Abstract Serine protease inhibitors (serpins) family have a complex mechanism of inhibition that requires a large scale conformational change. Antithrombin (AT), a member of serpin superfamily serves as a key regulator of the blood coagulation cascade, deficiency of which leads to thrombosis. In recent years, a handful of studies have identified small compounds that retard serpin polymerization but abrogated the normal activity. Here, we screened small molecules to find potential leads that can reduce AT polymer formation. We identified simple sugar molecules that successfully blocked polymer formation without a significant loss of normal activity of AT under specific buffer and temperature conditions. Of these, trehalose proved to be most promising as it showed a marked decrease in the bead like polymeric structures of AT shown by electron microscopic analysis. A circular dichroism (CD) analysis indicated alteration in the secondary structure profile and an increased thermal stability of AT in the presence of trehalose. Guanidine hydrochloride (GdnHCl)-based unfolding studies of AT show the formation of a different intermediate in the presence of trehalose. A time-dependent fluorescence study using 1,1′-bi(4-anilino)naphthalene-5,5′-disulfonic acid (Bis-ANS) shows that trehalose affects the initial conformational change step in transition from native to polymer state through its binding to exposed hydrophobic residues on AT thus making AT less polymerogenic. In conclusion, trehalose holds promise by acting as an initial scaffold that can be modified to design similar compounds with polymer retarding propensity.


Atmosphere ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 13
Author(s):  
Carolina Strohmaier ◽  
Manuel S. Krommweh ◽  
Wolfgang Büscher

A two-stage exhaust air treatment system installed at a broiler fattening facility with 40,000 animals was investigated. The facility’s exhaust air was treated first by use of a chemo-scrubber (stage 1) and afterwards by a vertical biofilter (stage 2). The biofilter was equipped with root wood and honeycombed paper pad layers (half/half) to enable a direct comparison of both filter materials’ suitability. Odour samples were taken on site and afterwards analysed at an olfactometry laboratory. Ammonia concentration values were collected continuously using a photoacoustic multi-gas monitor. High mitigation performance was achieved with both filter materials, with the honeycombed paper pad layer being less susceptible to fungal growth than the root wood filter. Cellulose seems to be a proper alternative for use in biofilters, but further research is needed to estimate the long-term stability of this material.


1997 ◽  
Vol 36 (8-9) ◽  
pp. 307-311 ◽  
Author(s):  
R. Y. G. Andoh ◽  
C. Declerck

Rapid urbanisation and its consequent increase in impermeable surface areas and changes in land use has generally resulted in problems of flooding and heavy pollution of urban streams and other receiving waters. This has often been coupled with ground water depletion and a threat to water resources. The first part of this paper presents an alternative drainage philosophy and strategy which mimics nature's way by slowing down (attenuating) the movement of urban runoff. This approach results in cost-effective, affordable and sustainable drainage schemes. The alternative strategy can be described as one of prevention rather than cure by effecting controls closer to source rather than the traditional approach which results in the transfer of problems downstream, resulting in its cumulation and the need for large scale, centralised control. The second part describes a research project which has been launched in order to quantify the cost and operational benefits of source control and distributed storage. Details of the methodology of the modelling and simulation processes which are being followed to achieve this target are presented.


1953 ◽  
Vol 31 (7) ◽  
pp. 665-672
Author(s):  
A. K. Wiebe ◽  
C. A. Winkler

A potential of −0.305 ± 0.005 volt (relative to a saturated calomel electrode) was obtained at a freshly prepared platinum surface within 30 sec. of immersion in oxygen-free N/5 sulphuric acid saturated with hydrogen. In electrolytes saturated with nitrogen or oxygen potentials of +0.05 ± 0.01 volt and +0.745 ± 0.005 volt respectively were more slowly attained. The times required for the electrode to reach maximum potentials, tmax, when it was made a cathode, and corresponding values of tmax when it was rendered anodic, were determined over a range of currents. The values of tmax appear to provide a method of determining the surface areas of platinum electrodes.


2013 ◽  
Vol 67 (8) ◽  
pp. 1816-1821 ◽  
Author(s):  
E. Hosseini Koupaie ◽  
M. R. Alavi Moghaddam ◽  
S. H. Hashemi

The application of a granular activated carbon-sequencing batch biofilm reactor (GAC-SBBR) for treatment of wastewater containing 1,000 mg/L Acid Red 18 (AR18) was investigated in this research. The treatment system consisted of a sequencing batch reactor equipped with moving GAC as biofilm support. Each treatment cycle consisted of two successive anaerobic (14 h) and aerobic (8 h) reaction phases. Removal of more than 91% chemical oxygen demand (COD) and 97% AR18 was achieved in this study. Investigation of dye decolorization kinetics showed that the dye removal was stimulated by the adsorption capacity of the GAC at the beginning of the anaerobic phase and then progressed following a first-order reaction. Based on COD analysis results, at least 77.8% of the dye total metabolites were mineralized during the applied treatment system. High-performance liquid chromatography analysis revealed that more than 97% of 1-naphthyalamine-4-sulfonate as one of the main sulfonated aromatic constituents of AR18 was removed during the aerobic reaction phase. According to the scanning electron microscopic analysis, the microbial biofilms grew in most cavities and pores of the GAC, but not on the external surfaces of the GAC.


1998 ◽  
Vol 29 ◽  
pp. S477-S478
Author(s):  
S. Mazoue ◽  
D. Gabay ◽  
A. Renoux ◽  
M. Attoui

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