scholarly journals Assessing the impact of nutrient loads on eutrophication in the semi-enclosed Izmir Bay combining observations and coupled hydrodynamic-ecosystem modelling

Author(s):  
OZGE YELEKCI ◽  
VALERIA IBELLO ◽  
BETTINA A. FACH ◽  
FILIZ KUCUKSEZGIN ◽  
CAGLAR YUMRUKTEPE ◽  
...  

Intense human activities may strongly affect coastal environments threatening natural, societal and economic resources. In order to propose adequate measures to preserve coastal marine areas, a thorough understanding of their physical and biogeochemical features is required. This study focuses on one such coastal area, Izmir Bay located in the Eastern Mediterranean Sea. Izmir Bay is a highly populated area subject to many human induced stressors such as pollution and eutrophication, that has been suffering high nutrient loads for decades. Despite the construction of the Çiğli waste water treatment plant in 2000-2001 to reduce eutrophication, such pressures continue to occur. To study the current physical and biogeochemical dynamics of Izmir Bay and their spatial and temporal variability, a three-dimensional coupled hydrodynamic-ecosystem model (Delft3D modelling suite’s FLOW and ECO modules) is implemented. Using the model, the effect of excessive inorganic nutrient loading on the marine ecosystem as the main cause of this eutrophication is explored in an effort to advise on mitigation efforts for the Bay focusing on eliminating eutrophication. Results of different model scenarios show that the Inner and Middle Bay are nitrogen-limited while the Outer Bay is phosphorus-limited. Inner regions are more sensitive to variations in inorganic nitrogen input due to the low (<16) N/P ratio of nutrients in seawater. An increase in inorganic nitrogen triggers eutrophication events with primary production as an immediate response. Conversely, the Outer Bay ecosystem with N/P ratios above 16 is more sensitive to phosphate inputs, of which an increase causes a considerable enhancement in algal production. This study shows the vulnerability of Izmir Bay to anthropogenic nutrient input and model simulations indicate that management plans should consider reducing DIN discharges both in the inner-middle zones of Izmir Bay as well as inputs from the Gediz River. Additionally, phosphate inputs should be reduced to avoid an overall increase of algal production in the Outer Bay, the larger part of Izmir Bay.

1996 ◽  
Vol 68 (7) ◽  
pp. 1179-1186 ◽  
Author(s):  
Stephen D. J. Booth ◽  
Daniel Urfer ◽  
Gerard Pereira ◽  
Karl J. Caber

2018 ◽  
Vol 874 ◽  
pp. 18-26
Author(s):  
Mila Tartiarini ◽  
Udisubakti Ciptomulyono

Waste water result from operating activities of Grati Combined Cycled Power Plant (CCPP) is significant amount and has potentially to be reutilized. A recycling unit as the pilot project has been applied in Grati CCPP PT Indonesia Power UP Perak Grati for capacity 4 tons/hour of service water product. Development plant of Grati CCPP up to year 2018 will produce more amounts of waste water, and potentially increase the pollution load in the unit area.Considering the use of alternative development for unit recycled waste water effluent from the Waste Water Treatment Plant (WWTP) has implications to the environmental and cost aspects, therefore a proper assessment to decide the alternative is needed. Proposed method of Life Cycle Assessment (LCA) is to measure the impact to the environment. And the Cost Benefit Analysis (CBA) is to measure the economic criteria. To integrate the results of the two methods, it is used and calculated by using Hierarcy Analytical Process (AHP).The result of the study about the environmental impact and economic analysis, the development of the recycling unit is required to process all waste water produced by power plants. Focus group by experts in power plant operation using AHP is based on the results of SimaPro 7.0 and CBA. The most beneficial result is with a single score of 0.2314 Pt / 1 ton of water service, the payback period of 2.5 years, 37.5% IRR and NPV US$ 88,577.23 and the MMF-RO unit for total capacity of 14 tons/hour has become the most alternative of development.


2013 ◽  
Vol 8 (2) ◽  
pp. 263-274 ◽  
Author(s):  
P. Ragazzo ◽  
L. Falletti ◽  
N. Chiucchini ◽  
G. Serra

Energy saving is an ever increasing need not only as a result of the growth in energy global demand and as a result of progressive erosion of supply sources. Another reason is that the environmental impact deriving from energy use is becoming more and more a reason for concern (60% increase of CO2 emissions over the last 30 years). Rationalizing energy use therefore is a goal in relation to global energy policies. Recently the European Union has developed a plan to reduce energy consumption (20% by 2020): it has issued rules and guidelines targeted at efficiency improvement in different areas such as infrastructure, products, processes and services. Energy saving is therefore a must in wastewater treatment, but one needs to achieve this target without damaging the process. That said, the objective could be reached only by acting contemporarily on technologies and relative selection criteria, designing procedures and, last but not least, Waste Water Treatment Plant monitoring and management practices. This paper focuses on these different areas pointing out opportunities, benefits and possible setbacks in relation to process performance, highlighting the impact of management operations. Starting from simple management variables, it also contains an example concerning the necessary instruments and the coordination of controls needed to regularly evaluate intervention needs and available margins. This paper also deals with the consequences of technologies encouraged as solutions for stable and effective processes, but which are in clear contrast to energy saving goals.


1992 ◽  
Vol 26 (9-11) ◽  
pp. 2547-2550 ◽  
Author(s):  
P. Romano ◽  
M. Ranzani

A full scale study was conducted to investigate the destination of LAS (Linear Alkylbenzene Sulfonate) in Italy's greatest WWTP (Waste Water Treatment Plant): the Turin central plant. Specific LAS data, using established HPLC techniques, have been obtained in the influent and effluent streams, in the dissolved phase (waters) and in the adsorbed one (suspended solids and sludges) to reach a complete mass balance. LAS removal higher than 99% and LAS biodegradation ca. 85% have been observed. Attention has been also given to LAS intermediates of biodegradation, namely the sulfo fenil carboxylaters (SPC) resorting to HPLC and GC-MS techniques, the latter after derivatization. On the basis of SPC data it is possible to measure esperimentally also the biodegradation in sewers before the WWTP (at least 12%) and the mineralization degree of LAS in the WWTP (ca. 80% vs. total biodegraded LAS). The impact of the WWTP on the LAS concentration of the Po river waters has been also considered.


2016 ◽  
Vol 9 (2) ◽  
Author(s):  
Dinda Rita K. Hartaja ◽  
Imam Setiadi

Generally, wastewater of nata de coco industry contains suspended solids and COD were high, ranging from 90,000 mg / l. The high level of of the wastewater pollutants, resulting in nata de coco industry can not be directly disposed of its wastewater into the environment agency. Appropriate technology required in order to process the waste water so that the treated water can meet the environmental quality standards that are allowed. Designing the waste water treatment plant that is suitable and efficient for treating industrial wastewater nata de coco is the activated sludge process. Wastewater treatment using activated sludge process of conventional (standard) generally consists of initial sedimentation, aeration and final sedimentation.Keywords : Activated Sludge, Design, IPAL


1991 ◽  
Vol 23 (4-6) ◽  
pp. 825-834 ◽  
Author(s):  
T. H. Lessel

The upgrading and nitrification was required for the waste water treatment plant in Geiselbullach. As space for more aeration tanks was not available, the possibility of increasing the MLSS by the use of submerged bio-film reactors was tested in a half technical scale pilot plant with three different reactor materials. Each tested reactor material caused a significant increase of MLSS and the nitrification reaction. The rope-type material was selected for the practical application, as it had not the same disadvantages of the other tested systems, which proved operational problems. After one year of continuous operation for nitrification in the full scale plant the influences on the biomass characteristics were investigated. Design criterias and details and operational data are reported.


1991 ◽  
Vol 24 (10) ◽  
pp. 161-170 ◽  
Author(s):  
M. D. Sinke

Until a century ago, The Hague's waste water was discharged directly into the city's canals. However, the obnoxious smell and resultant pollution of local waters and beaches then necessitated the implementation of a policy of collecting and transferring waste water by means of a system of sewers. By 1937, it was being discharged, via a 400 metre-long sea outfall, directly into the North Sea. By 1967, however, the increasing volume of waste water being generated by The Hague and the surrounding conurbations called for the construction of a primary sedimentation plant. This had two sea outfalls, one 2.5 km long and the other 10 km long, the former for discharging pre-settled waste water and the latter for discharging sludge directly into the North Sea. This “separation plant” was enlarged during the period 1986-1990. On account of the little available area - only 4.1 ha - the plant had to be enlarged in two stages by constructing a biological treatment section and a sludge treatment section with a capacity of 1,700,000 p.e. (at 136 gr O2/p.e./day). In order to gain additional space, a number of special measures were introduced, including aerating gas containing 90% oxygen and stacked final clarifiers. Following completion of the sludge treatment section, it has become possible, since 1st May 1990, to dump digested sludge into a large reservoir (“The Slufter”), specially constructed to accommodate polluted mud dredged from the Rotterdam harbours and waterways. As a result of these measures, there has been a reduction of between 70% and 95% in North Sea pollution arising from the “Houtrust” waste water treatment plant. Related investment totalled Dfl. 200 million and annual operating and maintenance costs (including investment charges) will amount to Dfl. 30 million. Further measures will have to be taken in the future to reduce the discharge of phosphorus and nitrogen. So this enlargement is not the end. There will be continued extension of the purification operations of the “Houtrust” waste water treatment plant.


1992 ◽  
Vol 25 (4-5) ◽  
pp. 225-232
Author(s):  
C. F. Seyfried ◽  
P. Hartwig

This is a report on the design and operating results of two waste water treatment plants which make use of biological nitrogen and phosphate elimination. Both plants are characterized by load situations that are unfavourable for biological P elimination. The influent of the HILDESHEIM WASTE WATER TREATMENT PLANT contains nitrates and little BOD5. Use of the ISAH process ensures the optimum exploitation of the easily degradable substrate for the redissolution of phosphates. Over 70 % phosphate elimination and effluent concentrations of 1.3 mg PO4-P/I have been achieved. Due to severe seasonal fluctuations in loading the activated sludge plant of the HUSUM WASTE WATER TREATMENT PLANT has to be operated in the stabilization range (F/M ≤ 0.05 kg/(kg·d)) in order not to infringe the required effluent values of 3.9 mg NH4-N/l (2-h-average). The production of surplus sludge is at times too small to allow biological phosphate elimination to be effected in the main stream process. The CISAH (Combined ISAH) process is a combination of the fullstream with the side stream process. It is used in order to achieve the optimum exploitation of biological phosphate elimination by the precipitation of a stripped side stream with a high phosphate content when necessary.


1996 ◽  
Vol 33 (12) ◽  
pp. 251-254
Author(s):  
Karl Arno Bäumer ◽  
Angela Baumann

The Institute for Water and Waste Management (ISA) at the Aachen University of Technology (RWTH) verified, through semi-technical analysis, the efficiency of the planned upgrade of the Kleve-Salmorth waste water treatment plant. Additionally the allowable biological phosphorus removal limit and the scheduled simultaneous precipitation were also ascertained.


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