A Collaborative Approach to Upgrading to Limits of Technology at the York River Treatment Plant

2009 ◽  
Vol 4 (3) ◽  
Author(s):  
I. Venner ◽  
J. Husband ◽  
J. Noonan ◽  
A. Nelson ◽  
D. Waltrip
Keyword(s):  
Chesapeake Bay ◽  
Phase 1 ◽  
Treatment Plant ◽  
Cost Effective ◽  
Design Flow ◽  
Nutrient Reduction ◽  
York River ◽  
Hampton Roads ◽  
Key Issues ◽  
Virginia Department

In response to rapid population growth as well as to address the nutrient reduction goals for the Chesapeake Bay established by the Virginia Department of Environmental Quality (VDEQ), the Hampton Roads Sanitation District (HRSD) initiated the York River Treatment Plant (YRTP) Expansion Phase 1 project. The existing YRTP is a conventional step-feed activated sludge plant and is rated for an average daily design flow of 57 million liters per day (MLD). This project proposes to expand the existing treatment capacity to 114 MLD and to reduce the nutrients discharged to the York River, a tributary for the Chesapeake Bay. In order to meet the effluent limits set by the VDEQ, a treatment upgrade to limit of technology (LOT) or enhanced nutrient removal (ENR) was required. Malcolm Pirnie worked with HRSD and the VDEQ to develop and evaluate ENR process alternatives to achieve the required effluent limits with the goal of determining the most reliable and cost effective alternative to achieve the aggressive nutrient reduction goals. This paper will highlight the key issues in determining the most desirable treatment process considering both economic and non-economic factors.

Cost-effective water treatment of polluted surface water by using direct filtration and granular activated carbon filtration

2002 ◽  
Vol 2 (1) ◽  
pp. 233-240 ◽  
Author(s):  
J. Cromphout ◽  
W. Rougge
Keyword(s):  
Activated Carbon ◽  
Water Treatment ◽  
Treatment Process ◽  
Treatment Plant ◽  
Granular Activated Carbon ◽  
Cost Effective ◽  
Water Treatment Plant ◽  
Direct Filtration ◽  
Carbon Filtration ◽  
Effective Water

In Harelbeke a Water Treatment Plant with a capacity of 15,000 m3/day, using Schelde river water has been in operation since April 1995. The treatment process comprises nitrification, dephosphatation by direct filtration, storage into a reservoir, direct filtration, granular activated carbon filtration and disinfection. The design of the three-layer direct filters was based on pilot experiments. The performance of the plant during the five years of operation is discussed. It was found that the removal of atrazin by activated carbon depends on the water temperature.

Two-stage chemical-biological treatment at Thessaloniki greater area WWTP - experiences and potentials

1995 ◽  
Vol 32 (9-10) ◽  
pp. 75-84 ◽  
Author(s):  
A. D. Andreadakis ◽  
G. H. Kristensen ◽  
A. Papadopoulos ◽  
C. Oikonomopoulos
Keyword(s):  
Biological Treatment ◽  
Treatment Plant ◽  
Cost Effective ◽  
Primary Treatment ◽  
Effective Control ◽  
Two Stage ◽  
Effluent Quality ◽  
Filamentous Microorganisms ◽  
Sludge Settling ◽  
The City

The wastewater from the city of Thessaloniki is discharged without treatment to the nearby inner part of the Thessaloniki Gulf. The existing, since 1989, treatment plant offers only primary treatment and did not operate since the expected effluent quality is not suitable for safe disposal to the available recipients. Upgrading of the plant for advanced biological treatment, including seasonal nitrogen removal, is due from 1995. In the mean time, after minor modifications completed in February 1992, the existing plant was put into operation as a two-stage chemical-biological treatment plant for 40 000 m3 d−1, which corresponds to about 35% of the total sewage flow. The operational results obtained during the two years operation period are presented and evaluated. All sewage and sludge treatment units of the plant perform better than expected, with the exception of the poor sludge settling characteristics, due to severe and persistent bulking caused by excessive growth of filamentous microorganisms, particularly M. Parvicella. Effective control of the bulking problem could lead to more cost-effective operation and increased influent flows.

scholarly journals Electrochemical Biosensors in Food Safety: Challenges and Perspectives

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2940
Author(s):  
Antonella Curulli
Keyword(s):  
Food Industry ◽  
Electrochemical Sensors ◽  
Cost Effective ◽  
Electrochemical Biosensors ◽  
Food Chains ◽  
Sensing Systems ◽  
Highly Sensitive ◽  
Skilled Personnel ◽  
Recent Developments ◽  
Key Issues

Safety and quality are key issues for the food industry. Consequently, there is growing demand to preserve the food chain and products against substances toxic, harmful to human health, such as contaminants, allergens, toxins, or pathogens. For this reason, it is mandatory to develop highly sensitive, reliable, rapid, and cost-effective sensing systems/devices, such as electrochemical sensors/biosensors. Generally, conventional techniques are limited by long analyses, expensive and complex procedures, and skilled personnel. Therefore, developing performant electrochemical biosensors can significantly support the screening of food chains and products. Here, we report some of the recent developments in this area and analyze the contributions produced by electrochemical biosensors in food screening and their challenges.

scholarly journals Toward Decentralised Sanitary Sewage Collection Systems: A Multiobjective Approach for Cost-Effective and Resilient Designs

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1886
Author(s):  
Arezoo Zahediasl ◽  
Amin E. Bakhshipour ◽  
Ulrich Dittmer ◽  
Ali Haghighi
Keyword(s):  
Treatment Plant ◽  
Drainage System ◽  
Cost Effective ◽  
Optimization Approach ◽  
Hydraulic Design ◽  
Multiobjective Approach ◽  
Layout Generation ◽  
Plant Allocation ◽  
Problem Solving Process

In recent years, the concept of a centralized drainage system that connect an entire city to one single treatment plant is increasingly being questioned in terms of the costs, reliability, and environmental impacts. This study introduces an optimization approach based on decentralization in order to develop a cost-effective and sustainable sewage collection system. For this purpose, a new algorithm based on the growing spanning tree algorithm is developed for decentralized layout generation and treatment plant allocation. The trade-off between construction and operation costs, resilience, and the degree of centralization is a multiobjective problem that consists of two subproblems: the layout of the networks and the hydraulic design. The innovative characteristics of the proposed framework are that layout and hydraulic designs are solved simultaneously, three objectives are optimized together, and the entire problem solving process is self-adaptive. The model is then applied to a real case study. The results show that finding an optimum degree of centralization could reduce not only the network’s costs by 17.3%, but could also increase its structural resilience significantly compared to fully centralized networks.

An application of Austrian legal requirements for CSO emissions

2011 ◽  
Vol 64 (5) ◽  
pp. 1081-1088 ◽  
Author(s):  
Manfred Kleidorfer ◽  
Wolfgang Rauch
Keyword(s):  
Model Calibration ◽  
Model Building ◽  
Treatment Plant ◽  
Cost Effective ◽  
Combined Sewer Overflows ◽  
Sewer System ◽  
Legal Requirements ◽  
Innovative Methods ◽  
Combined Sewer

The Austrian standard for designing combined sewer overflow (CSO) detention basins introduces the efficiency of the combined sewer overflows as an indicator for CSO pollution. Additionally criteria for the ambient water quality are defined, which comprehend six kinds of impacts. In this paper, the Austrian legal requirements are described and discussed by means of hydrological modelling. This is exemplified with the case study Innsbruck (Austria) including a description for model building and model calibration. Furthermore an example is shown in order to demonstrate how – in this case – the overall system performance could be improved by implementing a cost-effective rearrangement of the storage tanks already available at the inflow of the wastewater treatment plant. However, this guideline also allows more innovative methods for reducing CSO emissions as measures for better usage of storage volume or de-centralised treatment of stormwater runoff because it is based on a sewer system simulation.

In-vessel co-composting – a rapid resource recovery option for septage treatment in Indian cities

2018 ◽  
Vol 8 (4) ◽  
pp. 688-697 ◽  
Author(s):  
Anu Rachel Thomas ◽  
Martin Kranert ◽  
Ligy Philip
Keyword(s):  
Assessment Tool ◽  
Sewage Treatment ◽  
Treatment Plant ◽  
Cost Effective ◽  
Organic Load ◽  
Human Waste ◽  
Design Load ◽  
Solids Content ◽  
Chennai City ◽  
Indian Cities

Abstract Septage management is a challenging task across India as more than 44% of the population depends on septic tanks for human waste management. Septage collected from Chennai city, India, was found to be rich in nutrients even though the total solids content (<2%) and C/N are low. The current practice of septage disposal in Chennai city is co-treatment in existing sewage treatment plants. The main drawback of this method is that treatment efficiency could deteriorate if the organic load increased much beyond the design load of the treatment plant and would result in poor treated-water quality. In this context, the present study focused on the potential of in-vessel co-composting as a sustainable treatment option. In order to enhance the co-composting process, suitable co-substrates were identified for making the process efficient and cost-effective. The area under the temperature profile during composting was used as an assessment tool for the identification of the proper mix. Addition of mixed organic waste and coir pith waste (bulking agent) to the dewatered septage gave the highest area among the different combinations. Different waste combinations were investigated in order to assess the suitability for field scale application.

scholarly journals Countermeasures against Static Power Attacks

2021 ◽  
pp. 780-805
Author(s):  
Thorben Moos ◽  
Amir Moradi
Keyword(s):  
Process Variations ◽  
Cost Effective ◽  
Design Flow ◽  
Sensitive Information ◽  
Standard Cell ◽  
Aging Effects ◽  
Cell Library ◽  
Effective Option ◽  
Static Power ◽  
Power Attacks

In recent years it has been demonstrated convincingly that the standby power of a CMOS chip reveals information about the internally stored and processed data. Thus, for adversaries who seek to extract secrets from cryptographic devices via side-channel analysis, the static power has become an attractive quantity to obtain. Most works have focused on the destructive side of this subject by demonstrating attacks. In this work, we examine potential solutions to protect circuits from silently leaking sensitive information during idle times. We focus on countermeasures that can be implemented using any common digital standard cell library and do not consider solutions that require full-custom or analog design flow. In particular, we evaluate and compare a set of five distinct standard-cell-based hiding countermeasures, including both, randomization and equalization techniques. We then combine the hiding countermeasures with state-of-the-art hardware masking in order to amplify the noise level and achieve a high resistance against attacks. An important part of our contribution is the proposal and evaluation of the first ever standard-cell-based balancing scheme which achieves perfect data-independence on paper, i.e., in absence of intra-die process variations and aging effects. We call our new countermeasure Exhaustive Logic Balancing (ELB). While this scheme, applied to a threshold implementation, provides the highest level of resistance in our experiments, it may not be the most cost effective option due to the significant resource overhead associated. All evaluated countermeasures and combinations thereof are applied to a serialized hardware implementation of the PRESENT block cipher and realized as cryptographic co-processors on a 28nm CMOS ASIC prototype. Our experimental results are obtained through real-silicon measurements of a fabricated die of the ASIC in a temperature-controlled environment using a source measure unit (SMU). We believe that our elaborate comparison serves as a useful guideline for hardware designers to find a proper tradeoff between security and cost for almost any application.

scholarly journals Research Progress and Key Issues of Hydrodebenzylation of Hexabenzylhexaazaisowurtzitane (HBIW) in the Synthesis of High Energy Density Material Hexanitrohexaazaisowurtzitane (HNIW)

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 409
Author(s):  
Xiaofei Tang ◽  
Rui Zhu ◽  
Tianjing Shi ◽  
Yu Wang ◽  
Xiaochen Niu ◽  
...  
Keyword(s):  
Energy Density ◽  
High Performance ◽  
Research Effort ◽  
Specific Impulse ◽  
Cost Effective ◽  
High Energy ◽  
High Energy Density ◽  
Research Progress ◽  
Fourth Generation ◽  
Key Issues

High energy density materials (HEDM) are the subject of an extensive research effort in relation to the use of these compounds as components of rocket propellants, powders, and formulations of high-performance explosives. Hexanitrohexaazaisowurtzitane (HNIW, i.e., CL-20) has received much attention in these research fields for its specific impulse, burning rate, ballistics, and detonation velocity. In this paper, the development and performances of the explosives from the first to the fourth generation are briefly summarized, and the synthesis status of the fourth-generation explosive, HNIW, is reviewed. The key issues that restrict the development of industrial amplification synthesis of HNIW are analyzed, and the potential directions of development are proposed. It is pointed out that to synthesize new and efficient catalysts is the key to making the cost-effective manufacturing of CL-20 a reality.

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