scholarly journals DIFFERENT BIOLOGICALLY ACTIVATED SYSTEMS RESISTANCE TO INHIBITION

2005 ◽  
Vol 1 ◽  
pp. 105
Author(s):  
V. Račys ◽  
D. Kliaugaite ◽  
D. Jankūnaite ◽  
I. Urniežaite
Keyword(s):  
Activated Sludge ◽  
Environmental Protection ◽  
Organic Pollutants ◽  
Industrial Wastewater ◽  
Inhibition Test ◽  
Conventional Activated Sludge ◽  
Respiratory Inhibition ◽  
Resistance System ◽  
Persistant Organic Pollutants ◽  
Potential Applicability

Biologically activated sorbent (BAS) are believed to be more efficient than separate conventional activated sludge and sorbents systems in removing phenols and others persistant organic pollutants from wastewater. These days, applications of biological activated systems treatment for various kinds of industrial wastewater are attracting greater attention as one of the efficient technologies. But the process is not very good understood, and there is not much parameter, which could describe stability and reliability of system and which could compare different BAS systems. The aim of this study was to investigate the resistance of different biologically activated sorbents to inhibition using respirometric measurements. To choose the most resistant to inhibition biologically activated system from five BAS: BAS-A, BAS-B, BAS-C, BAS-D and conventional activated sludge for comparing. Also to evaluate potential applicability of respirometric method for monitoring bioactivity in BAS systems. The pesticide 3,5-dichlorenol was chosen as inhibitor compound for experiment. The respiratory inhibition measurements were done with different biologically activated systems using different concentration of pesticide. The experiment was accomplished using respiratory inhibition method which described in Lithuanian normative document for environmental protection (Land 45-2001): activated sludge respiratory inhibition test. In parallel saprophyte bacterial counts were determined by spread plate technique and calculated as amount of saprophyte in one litter. The results from both tests showed that the most resistance system to respiratory inhibition was BAS-A. Respirometric method is applicable for monitoring bioactivity in BAS systems.

PHA (polyhydroxyalkanoate) production potential of activated sludge treating wastewater

2002 ◽  
Vol 45 (12) ◽  
pp. 119-126 ◽  
Author(s):  
H. Takabatake ◽  
H. Satoh ◽  
T. Mino ◽  
T. Matsuo
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Organic Pollutants ◽  
Wastewater Treatment Plants ◽  
Recovery Process ◽  
Biodegradable Plastics ◽  
Operational Conditions ◽  
Conventional Activated Sludge ◽  
Dry Cell Weight ◽  
Dry Cell

The main purposes of wastewater treatment systems are to remove organic pollutants, but it would be very attractive if there were a way to recover the organic pollutants as valuable organic materials. One of the possible ways to recover organic pollutants in wastewater is to convert them into polyhydroxyalkanoates (PHAs), which are biodegradable plastics. In this study, 18 activated sludge samples in 4 wastewater treatment plants (WWTPs) in Tokyo, Japan, were evaluated for their potential to produce PHAs by aerobic batch experiments with excess supply of acetate as the sole carbon source. The activated sludge samples tested had the capability to accumulate PHA up to 18.8% of dry cell weight on average, with the range of 6.0% to 29.5%. The results showed that the maximum PHA content was dependent on the influent more than on the operational conditions of the activated sludge, and that conventional activated sludge produced PHA as much as anaerobic-aerobic activated sludge did. The PHA content achieved in this study is still low, and further improvement is needed to put into practice the recovery process of organic pollutants as biodegradable plastics by activated sludge.

High rate and compact single sludge pre-denitrification process for retrofit

1994 ◽  
Vol 30 (6) ◽  
pp. 31-40 ◽  
Author(s):  
Hiroyshi Emori ◽  
Hiroki Nakamura ◽  
Tatsuo Sumino ◽  
Tadashi Takeshima ◽  
Katsuzo Motegi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Treatment Plant ◽  
High Rate ◽  
Activated Sludge Process ◽  
Nitrogen And Phosphorus ◽  
Conventional Activated Sludge ◽  
Treatment Techniques ◽  
Conventional Activated Sludge Process ◽  
Denitrification Process

For the sewage treatment plants near rivers and closed water bodies in urbanized areas in Japan and European countries, there is a growing demand for introduction of advanced treatment processes for nitrogen and phosphorus from the viewpoints of water quality conservation and environmental protection. In order to remove nitrogen by the conventional biological treatment techniques, it is necessary to make a substantial expansion of the facility as compared with the conventional activated sludge process. In such urbanized districts, it is difficult to secure a site and much capital is required to expand the existing treatment plant. To solve these problems, a compact single sludge pre-denitrification process using immobilized nitrifiers was developed. Dosing the pellets, which are suitable for nitrifiers growth and physically durable, into the nitrification tank of single sludge pre-denitrification process made it possible to perform simultaneous removal of BOD and nitrogen in a retention time equal to that in the conventional activated sludge process even at the low water temperature of about 10 °C. The 3,000 m3/d full-scale conventional activated sludge plant was retrofitted and has been successfully operated.

Chemical characterization and biotreatability of effluents from an integrated alkaline-peroxide mechanical pulping/machine finish coated (APMP/MFC) paper mill

1997 ◽  
Vol 35 (2-3) ◽  
pp. 7-14 ◽  
Author(s):  
A. Schnell ◽  
M. J. Sabourin ◽  
S. Skog ◽  
M. Garvie
Keyword(s):  
Activated Sludge ◽  
Aquatic Toxicity ◽  
Wood Chip ◽  
Chemical Characterization ◽  
Toxicity Testing ◽  
Sampling Period ◽  
Paper Mill ◽  
Alkaline Peroxide ◽  
Conventional Activated Sludge ◽  
Treated Effluent

As part of an extensive audit of the Alkaline-Peroxide Mechanical Pulping (APMPTM) plant at the Malette Quebec Inc. mill in St. Raymond, Que., effluents were sampled from various stages of the process for comprehensive chemical characterizations, aquatic toxicity testing and anaerobic biotreatability assessments. In addition, untreated and secondary treated combined effluent from the integrated paper mill were sampled to determine the effectiveness of a conventional activated sludge process at the mill site. During the one-day sampling period, the APMP plant processed a mixed wood furnish consisting of 50% spruce/balsam fir and 50% aspen, with a chemical charge of 3.5% sodium hydroxide and 3.8% hydrogen peroxide on oven-dry fibre, while the Machine Finish Coated (MFC) paper production rate was 100 odt/d (oven dry metric tonnes per day). Measured production-specific contaminant discharge loadings from the novel APMP process were 56 kg BOD5/odt and 155 kg COD/odt in a combined effluent flow of 28 m3/odt. Sources of process effluent were chip washing, three stages of wood chip pretreatment and chemical impregnation (i.e., Impressafiner stages), interstate washing and pulp cleaning. The three Impressafiner pressates were found to be the most concentrated (i.e., 12-26 g COD/L) and toxic streams. Microtox testing of the pressates revealed EC50 concentrations of 0.07-0.34% v/v. The warm and concentrated effluents generated by the non-sulphur APMP process were found to be highly amenable to anaerobic degradation as determined by batch bioassay testing. Filterable BOD5 and COD(f) of the process effluents were reduced by 87-95% and 70-77%, respectively, with corresponding theoretical methane yields being attained. Acid-soluble dissolved lignin compounds exhibited biorecalcitrance, as revealed by limited removals of 34-55%, and were the main constituents contributing to residual COD(f), while resin and fatty acids (RFA) were reduced by 80-94%. The conservatively operated full scale activated sludge treatment process achieved a similar high 74% COD(f) removal from the whole mill effluent, while BOD5 and RFA reductions were virtually complete and the treated effluent was non-toxic, as measured by Microtox.

Micronutrient supplements for optimisation of the treatment of industrial wastewater using activated sludge

1999 ◽  
Vol 33 (18) ◽  
pp. 3707-3714 ◽  
Author(s):  
Joanna E Burgess ◽  
Joanne Quarmby ◽  
Tom Stephenson
Keyword(s):  
Activated Sludge ◽  
Industrial Wastewater
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