Full-Scale Experiences with Phosphate Crystallization in a Crystalactor®

1991 ◽  
Vol 23 (4-6) ◽  
pp. 819-824 ◽  
Author(s):  
E. Eggers ◽  
A. H. Dirkzwager ◽  
H. van der Honing

The first full-scale phosphate removal plant is nearly one year in operation. Values of 0.5 mg/l P or less are possible. No extra surplus sludge is produced, but a relatively small amount of waterfree pellets, which can be reused in the phosphate processing industry.

Antibiotics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 502
Author(s):  
Andrea Visca ◽  
Anna Barra Caracciolo ◽  
Paola Grenni ◽  
Luisa Patrolecco ◽  
Jasmin Rauseo ◽  
...  

Anaerobic digestion is one of the best ways to re-use animal manure and agricultural residues, through the production of combustible biogas and digestate. However, the use of antibiotics for preventing and treating animal diseases and, consequently, their residual concentrations in manure, could introduce them into anaerobic digesters. If the digestate is applied as a soil fertilizer, antibiotic residues and/or their corresponding antibiotic resistance genes (ARGs) could reach soil ecosystems. This work investigated three common soil emerging contaminants, i.e., sulfamethoxazole (SMX), ciprofloxacin (CIP), enrofloxacin (ENR), their ARGs sul1, sul2, qnrS, qepA, aac-(6′)-Ib-cr and the mobile genetic element intI1, for one year in a full scale anaerobic plant. Six samplings were performed in line with the 45-day hydraulic retention time (HRT) of the anaerobic plant, by collecting input and output samples. The overall results show both antibiotics and ARGs decreased during the anaerobic digestion process. In particular, SMX was degraded by up to 100%, ENR up to 84% and CIP up to 92%, depending on the sampling time. In a similar way, all ARGs declined significantly (up to 80%) in the digestate samples. This work shows how anaerobic digestion can be a promising practice for lowering antibiotic residues and ARGs in soil.


Worldview ◽  
1983 ◽  
Vol 26 (7) ◽  
pp. 18-21
Author(s):  
Avi Shlaim

The second government formed by Menachem Begin, following the Likud party's narrow victory in the June, 1981, elections, represented a real change in Israeli foreign policy. Dominated by a group of hard-liners committed to the ideology of "Greater Israel" and powered by a drive for regional hegemony, this government led Israel along a nationalistic and militant course, culminating within one year in a full-scale invasion of Lebanon. The election results, which gave the Likud 48 seats in the new Knesset compared with the Labor party's 47, hardly provided an unequivocal mandate for the pursuit of Begin's far-reaching political program, a program that can be summed up in the two words Eretz Yisrael—the whole land of Israel. Nor could a coalition with the religious parties, which commanded a wafer-thin majority of 61 in the 120-member Knesset, be considered a natural vehicle for bringing about such a radical change in foreign policy.


1990 ◽  
Vol 22 (9) ◽  
pp. 17-24 ◽  
Author(s):  
O. Tünay ◽  
O. Tameroǧlu ◽  
N. Baykal ◽  
F. Afşarünal ◽  
E. Ödemiş

In this paper, the pretreatment approaches in the textile processing industry are discussed and two case studies which have been carried out in two textile processing plants are delineated. Case studies include the phases of process and pollution profiles, treatability study, conceptual design and evaluation of one-year actual treatment plant performances. One of the treatment schemes applied was chemical coagulation while the other was activated sludge. Therefore a comparison of two main types of pretreatment has been realised. Results indicate that biological treatment is more efficient and reliable in terms of organic matter removal as compared to chemical coagulation. Comparisons of cost of initial investment, cost and ease of operation, and sludge production are also made and discussed.


1990 ◽  
Vol 22 (1-2) ◽  
pp. 281-292 ◽  
Author(s):  
P. Gilles

The technology that consists of treating sewage on submerged granular filters is now far beyond the stages of research and testing on pilot units. Fifteen or so full-scale facilities are in operation in France using, as a biological treatment stage, the fixed biomass technology as realised by the Biocarbone process, particularly for the treatment of sewage from built-up areas along the seaboard. These are cases where the advantages of this technique can be put to decisive use. The Mediterranean seaboard is an ideal site for this technology. Cases in point are the waterworks of Sanary Bandol (pop.60,000) and Perpignan (pop.160,000), that have been in operation for two years and one year respectively. Waterworks in Monaco (pop.100,000) and Antibes (pop.170,000) will be commissioned in 1989 using the same technology. Results obtained during intensive controls show that the fixed biomass, designed with a suitable industrial technology, is capable of producing in routine conditions, on full industrial-scale plant, a very good quality effluent. (COD : 70 mg/l, TSS : 20 mg/l) for pollutant loads in the order of 8 kg COD/m3 day. It enables the fluctuations in the daily flow-rate and pollution load of the influent to be absorbed. The units currently being built are examples of what can be done in compact roofed facilities incorporating a fixed biomass treatment stage, with the objective of reaching a no-nuisance level.


1997 ◽  
Vol 35 (2-3) ◽  
pp. 117-122 ◽  
Author(s):  
Thomas Welander ◽  
Anders Löfqvist ◽  
Anders Selmer

The possibility of improving the efficiency of aerated lagoons treating pulp and paper industry effluents by introducing a support material for microbial growth was studied on a pilot plant scale. Two 20 m3 pilot plants were operated for approximately one year in parallel with full-scale aerated lagoons at two Swedish pulp and paper mills. A support material specifically developed for application in aerated lagoons was installed in the pilot plants. A considerably higher treatment efficiency was obtained in the pilot plants than in the full-scale lagoons. While 30-40% of the COD was removed in the full-scale lagoons, a COD-removal of 60-70% was achieved in the pilot plants. Phosphorus, an important discharge parameter at both mills, was removed to 60-70%, while the removal in the full scale lagoons was only 0-10%. The suspended solids in the treated effluent after clarification was around 20 mg/l.


1987 ◽  
Vol 14 (2) ◽  
pp. 278-283 ◽  
Author(s):  
M. Florentz ◽  
M. C. Hascoet ◽  
F. Bourdon

In France, all phosphorus removal treatment has been based on precipitation by means of chemical reagents. With a view to reducing costs, a series of laboratory experiments was initiated and subsequently followed up by full-scale studies in early 1984 at the Saint-Mars-la-Jaille treatment plant. This is the first biological P-removal plant to be put on line in France.The plant operates at low loading levels with extended aeration. Nitrification–denitrification is achieved in controlled aerobic and nonaerobic zones through a multi-mini-step process in a plug–flow reactor. Complete nitrate removal results in a release of phosphorus during the anaerobic phase and, hence in a high level of phosphorus accumulation in the aerobic sludge.Phosphorus removal was optimized by replacing the thickener with a new flotation thickener to minimize P-release in the anaerobic sludge blanket. The phosphorus removal levels obtained varied from 35% at the outset of the study to 89% upon stabilization. This paper outlines the basic technical alterations made to ensure efficient phosphorus removal with this type of sewage plant as well as the analytical procedures used, and identifies the polyphosphates accumulated in activated sludge, on the basis of 31-phosphorus nuclear magnetic resonance (31P nmr).Results concerning phosphorus removal at low temperatures are also provided. Key words: activated sludge, wastewater treatment, biological phosphate removal, anaerobic conditions, restricted oxygen, nuclear magnetic resonance, flotation, temperature.


2009 ◽  
Vol 8 (2) ◽  
pp. 247-256 ◽  
Author(s):  
Stefan Börjesson ◽  
Ann Mattsson ◽  
Per-Eric Lindgren

Tetracycline-resistant bacteria and genes encoding tetracycline resistance are common in anthropogenic environments. We studied how wastewater treatment affects the prevalence and concentration of two genes, tetA and tetB, that encode resistance to tetracycline. Using real-time polymerase chain reaction (PCR) we analysed wastewater samples collected monthly for one year at eight key-sites in a full-scale municipal wastewater treatment plant (WWTP). We detected tetA and tetB at each sampling site and the concentration of both genes, expressed per wastewater volume or per total-DNA, decreased over the treatment process. The reduction of tetA and tetB was partly the result of the sedimentation process. The ratio of tetA and tetB, respectively, to total DNA was lower in or after the biological processes. Taken together our data show that tetracycline resistance genes occur throughout the WWTP, and that the concentrations are reduced under conventional operational strategies.


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