Development of the Membrane Filter Press for the Processing of Sewage Sludge

1992 ◽  
Vol 25 (4-5) ◽  
pp. 297-305 ◽  
Author(s):  
P. Lowe ◽  
D. Shaw
Keyword(s):  
Membrane Filter ◽  
Waste Water Treatment ◽  
Scale Up ◽  
Filter Press ◽  
The Past ◽  
Performance Guarantees ◽  
Capital Productivity ◽  
Pressing Cycle ◽  
Solids Content ◽  
The Uk

The dewatering of sewage sludges using filter presses has been in common use for the past 80 years. The technology was mainly used in the UK for large waste water treatment plants especially where woollen grease was extracted from the sludge. It was also associated with the predrying of sludge prior to incineration in Multi Hearth Furnaces. To meet the growing demand for drier cakes and better capital productivity the membrane filter press has been developed. With the introduction of improved polyelectrolytes, polymer dosing systems, insitu cloth washing and computerised control the average pressing cycle has been reduced from 4-6 hours to under two hours. At the same time the dry solids content of the cake has become more consistent and for most waste waters in excess of 30%. The use of on-site pilot plant trails to determine the design criteria is now the accepted approach enabling sensible scale up and the setting of performance guarantees.

A Comparative Study of Full-Scale Sludge Dewatering Equipment

1993 ◽  
Vol 28 (1) ◽  
pp. 37-45 ◽  
Author(s):  
Ina Andreasen ◽  
Bente Nielsen
Keyword(s):  
Comparative Study ◽  
Wastewater Treatment Plants ◽  
Membrane Filter ◽  
Filter Press ◽  
Full Scale ◽  
Sludge Dewatering ◽  
Dewatered Sludge ◽  
Solids Content ◽  
Very High ◽  
P Removal

A comparative study of 4 different types of full-scale sludge dewatering units was performed in 1990 by I. Krüger AS in co-operation with the equipment suppliers. The purpose of the study was to examine the capability of the dewatering equipment on the “new” sludge types from wastewater treatment plants with N and P removal. The achieved results have formed the basis of a financial evaluation comprising construction and operating costs. The objective of the evaluation is to compare the total costs involved in sludge dewatering and disposal. The relatively cheap types of dewatering units (belt filter press, solid bowl centrifuge) produce dewatered sludge with a lower dry solids content than the more expensive equipment (press centrifuge, membrane filter press). The latter types should consequently primarily be applied where the dewatered sludge has to meet special requirements and in situations in which disposal costs are very high.

Dowagers, Debs, Nuns and Babies: The Politics of Nostalgia and the Older Woman in the British Sunday Night Television Serial

2013 ◽  
Vol 10 (4) ◽  
pp. 769-784 ◽  
Author(s):  
Estella Tincknell
Keyword(s):  
Older Women ◽  
Social Role ◽  
Mature Female ◽  
Older Woman ◽  
Distinctive Features ◽  
The Past ◽  
Political Position ◽  
The Social ◽  
The Uk ◽  
Popular Television

The extensive commercial success of two well-made popular television drama serials screened in the UK at prime time on Sunday evenings during the winter of 2011–12, Downton Abbey (ITV, 2010–) and Call the Midwife (BBC, 2012–), has appeared to consolidate the recent resurgence of the period drama during the 1990s and 2000s, as well as reassembling something like a mass audience for woman-centred realist narratives at a time when the fracturing and disassembling of such audiences seemed axiomatic. While ostensibly different in content, style and focus, the two programmes share a number of distinctive features, including a range of mature female characters who are sufficiently well drawn and socially diverse as to offer a profoundly pleasurable experience for the female viewer seeking representations of aging femininity that go beyond the sexualised body of the ‘successful ager’. Equally importantly, these two programmes present compelling examples of the ‘conjunctural text’, which appears at a moment of intense political polarisation, marking struggles over consent to a contemporary political position by re-presenting the past. Because both programmes foreground older women as crucial figures in their respective communities, but offer very different versions of the social role and ideological positioning that this entails, the underlying politics of such nostalgia becomes apparent. A critical analysis of these two versions of Britain's past thus highlights the ideological investments involved in period drama and the extent to which this ‘cosy’ genre may legitimate or challenge contemporary political claims.

Science, Politics, and the Pandemic

2020 ◽  
Vol 119 (820) ◽  
pp. 303-309
Author(s):  
J. Nicholas Ziegler
Keyword(s):  
United States ◽  
Biomedical Research ◽  
Scale Up ◽  
Political Leadership ◽  
The United States ◽  
Scientific Advice ◽  
The United Kingdom ◽  
Effective Policy ◽  
Scientific Expertise ◽  
The Uk

Comparing the virus responses in Germany, the United Kingdom, and the United States shows that in order for scientific expertise to result in effective policy, rational political leadership is required. Each of these three countries is known for advanced biomedical research, yet their experiences in the COVID-19 pandemic diverged widely. Germany’s political leadership carefully followed scientific advice and organized public–private partnerships to scale up testing, resulting in relatively low infection levels. The UK and US political responses were far more erratic and less informed by scientific advice—and proved much less effective.

scholarly journals Metaphors of migration over time

2021 ◽  
pp. 095792652199215
Author(s):  
Charlotte Taylor
Keyword(s):  
Emigration And Immigration ◽  
Emigrants And Immigrants ◽  
Economic Resource ◽  
Historical Discourse ◽  
Continuity And Change ◽  
The Past ◽  
Perception Of Control ◽  
Time Period ◽  
Metaphor Use ◽  
The Uk

This paper aims to cast light on contemporary migration rhetoric by integrating historical discourse analysis. I focus on continuity and change in conventionalised metaphorical framings of emigration and immigration in the UK-based Times newspaper from 1800 to 2018. The findings show that some metaphors persist throughout the 200-year time period (liquid, object), some are more recent in conventionalised form (animals, invader, weight) while others dropped out of conventionalised use before returning (commodity, guest). Furthermore, we see that the spread of metaphor use goes beyond correlation with migrant naming choices with both emigrants and immigrants occupying similar metaphorical frames historically. However, the analysis also shows that continuity in metaphor use cannot be assumed to correspond to stasis in framing and evaluation as the liquid metaphor is shown to have been more favourable in the past. A dominant frame throughout the period is migrants as an economic resource and the evaluation is determined by the speaker’s perception of control of this resource.

MONARCHS, TRAVELLERS AND EMPIRE IN THE PACIFIC'S AGE OF REVOLUTIONS

2020 ◽  
Vol 30 ◽  
pp. 77-96
Author(s):  
Sujit Sivasundaram
Keyword(s):  
Pacific Islanders ◽  
Modern World ◽  
Global History ◽  
The Past ◽  
The Pacific ◽  
Cultural Terms ◽  
The Pacific Ocean ◽  
Definition Of ◽  
The Uk ◽  
A Site

AbstractThe Pacific has often been invisible in global histories written in the UK. Yet it has consistently been a site for contemplating the past and the future, even among Britons cast on its shores. In this lecture, I reconsider a critical moment of globalisation and empire, the ‘age of revolutions’ at the end of the eighteenth century and the start of the nineteenth century, by journeying with European voyagers to the Pacific Ocean. The lecture will point to what this age meant for Pacific islanders, in social, political and cultural terms. It works with a definition of the Pacific's age of revolutions as a surge of indigeneity met by a counter-revolutionary imperialism. What was involved in undertaking a European voyage changed in this era, even as one important expedition was interrupted by news from revolutionary Europe. Yet more fundamentally vocabularies and practices of monarchy were consolidated by islanders across the Pacific. This was followed by the outworkings of counter-revolutionary imperialism through agreements of alliance and alleged cessation. Such an argument allows me, for instance, to place the 1806 wreck of the Port-au-Prince within the Pacific's age of revolutions. This was an English ship used to raid French and Spanish targets in the Pacific, but which was stripped of its guns, iron, gunpowder and carronades by Tongans. To chart the trajectory from revolution and islander agency on to violence and empire is to appreciate the unsettled paths that gave rise to our modern world. This view foregrounds people who inhabited and travelled through the earth's oceanic frontiers. It is a global history from a specific place in the oceanic south, on the opposite side of the planet to Europe.

scholarly journals Vulnerable bodies and invisible work: The Covid-19 pandemic and social reproduction

2021 ◽  
pp. 135822912110313
Author(s):  
Ellen Gordon-Bouvier
Keyword(s):  
Social Reproduction ◽  
The State ◽  
Family Unit ◽  
State Response ◽  
The Past ◽  
Invisible Work ◽  
The Uk ◽  
Liberal Individualism

The restrained state has always sought to devalue socially reproductive work, often consigning it to the private family unit, where it is viewed as a natural part of female relational roles. This marginalisation of social reproduction adversely affects those performing it and reduces their resilience to vulnerability. The pandemic has largely shattered the liberal illusions of autonomous personhood and state restraint. The reality of our universal embodied vulnerability has now become impossible to ignore, and society’s reliance on socially reproductive work has therefore been pushed into public view. However, the pandemic has also exacerbated harms and pressures for those performing paid and unpaid social reproduction, creating a crisis that demands an urgent state response. As it is argued in this paper, the UK response to date has been inadequate, illustrating an unwillingness to abandon familiar principles of liberal individualism. However, the pandemic has also created a climate of exceptionality, which has prompted even the most neoliberal of states to consider measures that in the past would have been dismissed. In this paper, it is imagined how the state can use this opportunity to become more responsive and improve the resilience of social reproduction workers, both inside and outside the home.

Enhanced sludge conditioning by enzyme pre-treatment: comparison of laboratory and pilot scale dewatering results

2006 ◽  
Vol 54 (5) ◽  
pp. 33-41 ◽  
Author(s):  
D. Dursun ◽  
M. Turkmen ◽  
M. Abu-Orf ◽  
S.K. Dentel
Keyword(s):  
Extracellular Polymeric Substances ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Solid Content ◽  
Filter Press ◽  
Treatment Comparison ◽  
Anaerobically Digested Sludge ◽  
Network Strength ◽  
Pre Treatment ◽  
Solids Content

The effect of enzyme pre-treatment on dewaterability of anaerobically digested sludge was investigated at both laboratory and pilot scale. Our results revealed a significant increase in cake solid content (27% cake solids compared to 18% without enzyme pre-treatment), using an enzyme dose of only 20 mg/L. In order to assess practical application, enzyme pre-treatment was applied at the Wilmington, Delaware (US) wastewater treatment plant, using a pilot-scale centrifuge. However, the efficiency reached in laboratory scale could not be obtained in pilot scale, where the final cake solids content did not exceed 20%. Centrifuge and belt filter press (simulated by Crown Press™) dewatering were compared in terms of the process efficiencies in the absence and presence of enzyme pre-treatment. Possible factors that might cause the differences were tested by experimental and statistical comparisons. Results indicated that the higher shear applied in centrifugation is responsible for the lack of improved cake solids. The network strength of sludge determined by rheological measurements revealed that enzymatic treatment weakens the gel structure of the sludge floc through the hydrolysis of extracellular polymeric substances; this allows improved dewatering by filtration processes, but leads to floc deterioration when subjected to high shear during centrifugation.

The EU as an “enforcement patchwork”: the impact of national enforcement for compliance with EU water law in Spain and Britain

2013 ◽  
Vol 34 (2) ◽  
pp. 331-353 ◽  
Author(s):  
Mónica García Quesada
Keyword(s):  
Waste Water Treatment ◽  
National Level ◽  
State Level ◽  
Detailed Examination ◽  
Deterrent Effect ◽  
Eu Law ◽  
Wide Range ◽  
The Uk ◽  
The Impact ◽  
The Eu

AbstractFailures of compliance with European Union (EU) directives have revealed the EU as a political system capable of enacting laws in a wide range of different policy areas, but facing difficulties to ensure their actual implementation. Although the EU relies on national enforcement agencies to ensure compliance with the EU legislation, there is scarce analysis of the differential deterrent effect of national enforcement in EU law compliance. This article examines the enforcement of an EU water directive, the Urban Waste Water Treatment Directive, in Spain and the UK. It focuses on the existing national sanctions for disciplining actors in charge of complying with EU requirements, and on the actual use of punitive sanctions. The analysis shows that a more comprehensive and active disciplinary regime at the national level contributes to explain a higher degree of compliance with EU law. The article calls for a detailed examination of the national administrative and criminal sanction system for a more comprehensive understanding of the incentives and disincentives to comply with EU law at the national state level.

How do junior doctors spend their time in an Acute Medical Unit?

2015 ◽  
Vol 14 (2) ◽  
pp. 57-60
Author(s):  
Eirini V Kasfiki ◽  
◽  
Mamoon Yusaf ◽  
Jivendra Gosai ◽  
Makani Purva ◽  
...  
Keyword(s):  
General Practice ◽  
Hospital Admission ◽  
Postgraduate Training ◽  
Junior Doctors ◽  
Bed Occupancy ◽  
Medical Unit ◽  
Admission Rates ◽  
The Past ◽  
Acute Medical Unit ◽  
The Uk

In the UK, postgraduate training for doctors has undergone significant changes over the past decade general practice, etc. During this period, hospital admission rates and bed occupancy have also increased.

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