Compact high-rate treatment of wastewater

2004 ◽  
Vol 4 (1) ◽  
pp. 23-33
Author(s):  
H. Ødegaard ◽  
Z. Liao ◽  
E. Melin ◽  
H. Helness

Many cities need to build compact wastewater treatment plants because of lack of land. This paper discusses compact treatment methods. An enhanced primary treatment process based on coarse media filtration is analysed. A high-rate secondary wastewater treatment process has specifically been investigated, consisting of a highly loaded moving bed biofilm reactor directly followed by a coagulation and floc separation step. The objective with this high-rate process is to meet secondary treatment effluent standards at a minimum use of chemicals, minimum sludge production and minimum footprint. It is demonstrated that the biofilm in the bioreactor mainly deals with the soluble organic matter while coagulation deals with the colloidal matter. The bioreactor may, therefore, be designed based on the soluble COD loading only, resulting in a very compact plant when a compact biomass/floc separation reactor (i.e. flotation or direct filtration) is used. The paper reports specifically on the coagulant choice in flotation and filter run time in direct filtration.

1993 ◽  
Vol 28 (10) ◽  
pp. 351-359 ◽  
Author(s):  
H. Ødegaard ◽  
B. Rusten ◽  
H. Badin

In 1988 the State Pollution Control Authority in Norway made recommendations regarding process designs for small wastewater treatment plants. Amongst these were recommendations for biological/chemical plants where biofilm reactors were used in combination with pretreatment in large septic tanks and chemical post treatment. At the same time the socalled “moving bed biofilm reactor” (MBBR) was developed by a Norwegian company. In this paper, experiences from a small wastewater treatment plant, based on the MBBR and on the recommendations mentioned, will be presented.


2019 ◽  
Vol 11 (23) ◽  
pp. 6658 ◽  
Author(s):  
I-Tae Kim

This study was conducted to secure the sustainability of biogas plants for generating resources from food waste (FW) leachates, which are prohibited from marine dumping and have been obligated to be completely treated on land since 2013 in South Korea. The aim of this study is to reduce the nitrogen load of the treatment process while producing bio-methanol using digested FW leachate diverted into wastewater treatment plants. By using biogas in conditions where methylobacter (M. marinus 88.2%) with strong tolerance to highly chlorinated FW leachate dominated, 3.82 mM of methanol production and 56.1% of total nitrogen (TN) removal were possible. Therefore, the proposed method can contribute to improving the treatment efficiency by accommodating twice the current carried-in FW leachate amount based on TN or by significantly reducing the nitrogen load in the subsequent wastewater treatment process. Moreover, the produced methanol can be an effective alternative for carbon source supply for denitrification in the subsequent process.


2013 ◽  
Vol 48 (3) ◽  
pp. 255-265 ◽  
Author(s):  
Kerry McPhedran ◽  
Rajesh Seth ◽  
Min Song ◽  
Shaogang Chu ◽  
Robert J. Letcher

Municipal wastewater treatment plants (MWTPs) are impacted by down-the-drain influents of anthropogenic chemicals. These chemicals are in consumer products and include the flame retardant tetrabromobisphenol A (TBBPA) and antimicrobial triclosan (TCS). Characterization of the distribution of TBBPA, TCS and the TBBPA product tribromobisphenol A (tri-BBPA) was determined at five stages along the treatment process of a typical Canadian MWTP facility. Overall, the TCS concentrations for both liquid (influents, primary effluents and final effluents (FEs)) and solid samples (primary and waste activated sludges) were similar to reported ranges in the literature. In contrast to TCS, both TBBPA and tri-BBPA concentrations were scarcely available in the literature. The TBBPA concentrations were within literature ranges for both influents and sludges, while the tri-BBPA sludge concentrations were markedly higher than a single available previous study. Mass balances for TCS, TBBPA and tri-BBPA indicated 7, 9 and 42%, respectively, of each chemical remaining in the FEs. The resultant annual mass loadings into the Detroit River were estimated to be 3.3 kg, 6.57 g, and 21.5 g for TCS, TBBPA and tri-BBPA, respectively.


2006 ◽  
Vol 53 (11) ◽  
pp. 27-33 ◽  
Author(s):  
K. Komori ◽  
Y. Okayasu ◽  
M. Yasojima ◽  
Y. Suzuki ◽  
H. Tanaka

Nonylphenol (NP) is known to be a byproduct of nonylphenol ethoxylates (NPnEO) which are used as detergents in industry. It is important that not only NP but also NPnEO and their related substances are analysed when behaviour of NP in the wastewater treatment process is surveyed. NPnEO are biodegraded to shorter ethoxylate (EO) chain NPnEO or nonylphenol carboxylates (NPnEC) under aerobic conditions, and then biodegraded to NP under anaerobic conditions. NP is one of the suspected endocrine disruptors (ED). Moreover, shorter EO chain NPnEO has greater toxicity than longer EO chain NPnEO. We conducted a field survey of NP and its related substances in 20 wastewater treatment plants (WWTP). The concentrations (median) of NP and its related substances in the WWTPs' influent ranged from 0.1 to 8.3 μg/L, showing NP concentration as the same level as those previously reported. The reduction of the long EO chain NPnEO in the WWTPs was almost complete, while the removal efficiency for the short EO chain NPnEO was less significant than the long EO chain NPnEO, suggesting that the degradation rate of the short EO chain NPnEO was lower than that of the long EO chain NPnEO in the wastewater treatment processes.


2006 ◽  
Vol 53 (11) ◽  
pp. 51-63 ◽  
Author(s):  
N. Nakada ◽  
M. Yasojima ◽  
Y. Okayasu ◽  
K. Komori ◽  
H. Tanaka ◽  
...  

Understanding of the fate of oestrogen and oestrogenic compounds is important in improving the removal efficiency for oestrogens in wastewater treatment plants (WWTPs). In this study an attempt was made to clarify the fate of oestrogen, oestrogen sulphates, and oestrogenic compounds (synthetic oestrogen, nonylphenol and its relatives) by an instrumental analysis, and the fate of oestrogenicity by an in vitro assay. The investigation was conducted in an activated sludge WWTP in winter and summer, focusing on identification of the primary substances that induce oestrogenicity. Wastewater samples were analysed by employing the silica-gel fractionation technique in conjunction with two-step column chromatography. The results revealed that, in winter, the WWTP efficiencies for the removal of nitrogen and oestrogens decreased and the oestrone level increased with the progress of the treatment. Oestrone and oestrogenic substances are likely to circulate between the aeration tank and the final sedimentation tank. In summer, however, these compounds were effectively removed in the WWTP. The results of the column chromatography coupled with the bioassay suggested that E1 and E2 are the predominant contributors to the oestrogenicity in the influent, return sludge and effluent of the WWTP. The measurement by the instrumental analysis supported these findings.


1996 ◽  
Vol 33 (1) ◽  
pp. 71-79
Author(s):  
T. Kanaya ◽  
K. Hirabayashi ◽  
I. Fujita ◽  
K. Tsumura

A basic of process control is to understand process conditions with measuring instruments and to operate processes so as to realize target conditions. If input measured values were inaccurate, output of manipulated variables would become improper and, as a result, it would be difficult to bring the process to the desired condition. In the wastewater treatment process, thanks to the latest progress in sensor technology, numerous automatic measuring instruments have been introduced. However, because of adverse environmental conditions peculiar to the wastewater treatment process such as slime-contaminated sensing elements, long-term continuous measurement is rather difficult. We believe such disadvantages in the measurement are making automatic control of the process very difficult to achieve. Under such circumstances, we have developed a detection system for unusual data which automatically checks six items of deviation from upper and lower limit values, rate of change (too much or too little), collating data from similar measuring instruments, etc. based on the measuring data of the last 30 days. With this system, validity of the accumulated data is being checked using measuring data. Accordingly, it enables us to deal with characteristics of measuring instruments, situations of wastewater treatment plants, seasonal changes, etc. automatically. In this report, automatic methods to establish judgement criteria, structure of this detection system and logic of detection of unusual data are introduced. Furthermore, test results with the data collected from actual wastewater treatment plants are covered.


Sign in / Sign up

Export Citation Format

Share Document