1973 ◽  
Vol 8 (1) ◽  
pp. 122-147
Author(s):  
J. D. O’Blenis ◽  
T.R. Warriner

Abstract The current widespread practice of disposal of water filtration plant wastes by direct discharge to receiving waters is coming under critical review by regulatory agencies. Among the alternatives for management of these wastes is the possibility of disposal to sanitary sewer systems. Since a recent nation-wide survey had established alum sludge as the most common waste generated by filtration plants, research was initiated to study the effects of water plant alum sludge on primary sewage treatment. A pilot primary sewage treatment plant was constructed and operated with a raw sewage feed of five litres per minute. A laboratory jar test program was conducted to supplement pilot plant operation. Sludges from two different water purification plants were tested along with alum and combinations of alum and water purification plant sludge for their effects on the removal of suspended solids, chemical oxygen demand (COD) and phosphates. The data showed jar testing to be a good indicator of pilot plant performance. Suspended solids, COD and phosphate removal efficiencies were improved by the addition of the sludges. The phosphate removal capacity of water treatment plant alum sludge was approximately the same as that reported for aluminum hydroxide, or about 1/7 to 1/9 of that determined for alum (as Aluminum). Recycling of the sludges improved phosphate removal performance.


1997 ◽  
Vol 32 (1) ◽  
pp. 7-22 ◽  
Author(s):  
H.O. Schroeter

Abstract Annual flow volumes and contaminant mass discharges from such sources as stormwater runoff, combined sewer overflows (CSOs) and sewage treatment plant (STP) effluents were computed for 47 urban centres located in 17 Canadian Areas of Concern (AOCs). Urban centres were defined as entities with sewage treatment plants servicing populations greater than 1,000. The relative annual flow volume contribution from individual sources varies significantly among AOC areas. By effluent type, stormwater runoff contributes 17 to 65%, CSOs 1 to 6%, and STP effluents about 35 to 80%. During wet weather, this distribution changes significantly, and stormwater runoff, CSOs and STP effluents contribute about 80, 7 and 13% of the total volume, respectively. In terms of annual solids loadings in the AOCs, stormwater runoff generates 49 to 96%, CSOs 2 to 20%, and STP effluents 4 to 39%. During wet weather, the solid loads are generated almost entirely by stormwater runoff and CSOs. For calculation of contaminant loadings, the concentration data from large urban and industrial catchments and a few smaller communities with mostly residential land were pooled together and used to compute loadings for other areas. Therefore, the computed loads are considered order-of-magnitude estimates, which are sufficient for planning level analyses. More accurate estimates would require local contaminant concentrations and flow data. The highest annual loadings of toxic contaminants were found for trace metals, followed by total PCBs, and a few trace organic compounds. In general, stormwater runoff contributed the largest contaminant loading. In most cases, a detailed assessment of the relative contaminant contributions from various sources and for various trace organic compounds was not possible because most of the data were at or below the analytical detection limit.


1990 ◽  
Vol 22 (7-8) ◽  
pp. 105-112 ◽  
Author(s):  
H. H. Hahn ◽  
E. Hoffmann ◽  
A. Kleinschmidt ◽  
R. Klute

The Standards controlling sewage treatment are continuously in development. Thus, upgrading existing plants is a frequently encountered problem. In the past this meant structural changes, mostly in terms of enlargement of existing facilities or addition of new units. More recently the possibilities of improving plant performance through chemicals addition (inducing precipitation and coagulation) with or without intensified biological treatment have been explored. Chemicals addition has become necessary in many instances due to the tightening of standards for phosphorous concentrations in the plant effluent. The present discussion is based on a case study where possibilities and limits of chemical and/or biological upgrading have been investigated. The analysis showed that neither chemical stages nor secondary biological stages alone can guarantee the effluent standards formulated by the water authorities.


2001 ◽  
Vol 44 (2-3) ◽  
pp. 49-56
Author(s):  
C. Paffoni

Upon the filling of the Seine Centre sewage plant in May 1998, the SIAAP commissioned its first wastewater treatment plant adapted for handling part of the large amounts of rain period surplus water: its flow rate ranges from 2.8 m3/s during dry weather to 12 m3/s in wet weather conditions. Four operational configurations for treating 240,000 m3/day during dry weather, with different quality objectives, and three configurations for treating the rain period surplus water were designed. Immediately upon filling of the plant, however, the operators had to devise innovative configurations for meeting new discharge standards. This paper will aim at demonstrating (considering a major achievement the various aspects of which will be explained) the SIAAP's will to conform in real time, through a dynamic management of its facilities, to the variation of the priorities in the environmental demands, while preserving the quality of the adjacent owners' immediate environment.


2005 ◽  
Vol 52 (8) ◽  
pp. 273-278 ◽  
Author(s):  
O. Braga ◽  
G.A. Smythe ◽  
A.I. Schafer ◽  
A.J. Feitz

The concentrations of two natural estrogens (estrone (E1) and Estradiol (E2)) and one synthetic progestin (Ethinylestradiol (EE2)) were measured for different unit operations in an advanced sewage treatment plant and in a large coastal enhanced primary sewage treatment plant. The average influent concentration to both plants was similar: 55 and 53ng/L for E1 and 22 and 12ng/L for E2 for the advanced and enhanced primary STPs, respectively. The activated sludge process at the advanced STP removed up to 85% and 96% of E1 and E2, respectively. The enhanced primary sewage treatment plant was mostly ineffective at removing the steroids with only 14% of E1 and 5% of E2 being removed during the treatment process. EE2 was not been detected during the study period in the influent or effluent of either STP. The difference in the observed removal between the two plants is primarily linked to plant performance but the extent to which removal of steroid estrogens is due to bacterial metabolism (i.e. the advanced STP) rather than adsorption to the bacterial biomass remains unclear. The poor removal observed for the coastal enhanced primary STP may have implications for the receiving environment in terms of a greater potential for abnormal reproductive systems in marine animals, particularly if discharges are into large bays or harbours where flushing is limited.


2020 ◽  
Vol 15 (2) ◽  
pp. 142-151
Author(s):  
Peter Lukac ◽  
Lubos Jurik

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.


2008 ◽  
Vol 37 (2) ◽  
Author(s):  
Maciej Walczak

Changes of microbial indices of water quality in the Vistula and Brda rivers as a result of sewage treatment plant operationThis paper reports the results of studies of microbiological changes in the water quality of the Vistula and Brda rivers after the opening of sewage treatment plants in Bydgoszcz. The study involved determining the microbiological parameters of water quality. Based on the results obtained, it was found that the quality of the water in both rivers had improved decidedly after the opening of the plants, although an increased number of individual groups of microorganisms was found at the treated sewage outlet from one of the plants.


2000 ◽  
Vol 36 (4) ◽  
pp. 161-171
Author(s):  
KENITSU KONNO ◽  
NAOKI ABE ◽  
YOSHIRO SATO ◽  
KOJI AKAMATSU ◽  
MAKOTO ABE ◽  
...  

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