Comparison of the toxicogenetic potential of sewage sludges from different treatment processes focusing agricultural use

The wastewater of approx. 800 000 inhabitants and population equivalents is treated at the mechanical aeration wastewater treatment plant Düsseldorf-Nord. The dry-weather flow amounts to 145 000m3/d, of which 40 % is industrial waste water. The combined sludge-primary sludge from the mechanical part and waste-activated sludge from the final settling tanks has been anaerobically stabilized, then chemically conditioned, dewatered in filter presses and to a large extent used agriculturally. Satisfactory performance could be obtained with this type of sludge treatment and no special problems occurred. As agricultural use has become more restricted due to new laws on sludges from treatment processes, and no adequate land-fill is available, the present plant has been expanded by a multiple hearth incinerator, to minimize the sludge volume. At the same time, a centrifuge, after which the dewatered sludge is mixed with ashes, has been installed in the dewatering plant. The construction costs for the installation of the multiple hearth furnace and centrifuge were approx. 18,5 million DM.

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Metals in Sewage Sludge and their Potential Effects in Agriculture

Water Science & Technology ◽

10.2166/wst.1983.0018 ◽

1983 ◽

Vol 15 (1) ◽

pp. 209-225 ◽

Cited By ~ 12

Author(s):

E G Coker ◽

P J Matthews

Keyword(s):

Sewage Sludge ◽

Food Chain ◽

Toxic Metals ◽

Large Body ◽

Potentially Toxic Metals ◽

Sewage Sludges ◽

Agricultural Use ◽

Industrial Sources ◽

Available Information

Metals accumulate in sewage sludges from domestic and industrial sources. Where such sludges are used in agriculture, the metals may contaminate land to such an extent that the quality and yield of crops is affected. Control of the industrial sources of sludge applications will avoid these problems. The paper reviews available information in the chemistry of the most significant potentially toxic metals in soils and their effects on crops including contamination of the food chain ending with man. The paper emphasises the large body of information available but underlines the need for more data if greater certainty is to evolve in the guidelines produced for the agricultural use of sludge and trade effluent control.

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Advanced wastewater treatment processes remove pharmaceuticals

AccessScience ◽

10.1036/1097-8542.br0114201 ◽

2020 ◽

Keyword(s):

Wastewater Treatment ◽

Treatment Processes ◽

Advanced Wastewater Treatment

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Supplemental Material for Empirical Bayes MCMC Estimation for Modeling Treatment Processes, Mechanisms of Change, and Clinical Outcomes in Small Samples

Journal of Consulting and Clinical Psychology ◽

10.1037/a0035889.supp ◽

2014 ◽

Cited By ~ 2

Keyword(s):

Clinical Outcomes ◽

Empirical Bayes ◽

Small Samples ◽

Mechanisms Of Change ◽

Treatment Processes ◽

Mcmc Estimation

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Treatment processes in mental health care: what's going on?

Psychiatrische Praxis ◽

10.1055/s-0031-1277732 ◽

2011 ◽

Vol 38 (S 01) ◽

Author(s):

R McCabe

Keyword(s):

Mental Health ◽

Health Care ◽

Mental Health Care ◽

Treatment Processes

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DECOLOURIZATION AND COD REMOVAL OF WASEWATER FROM ETHANOL PRODUCTION PROCESS FROM MOLASSES BY COAGULANTION USING INORGANIC ALUM

Science and Technology Development Journal ◽

10.32508/stdj.v13i3.2146 ◽

2010 ◽

Vol 13 (3) ◽

pp. 92-102

Author(s):

Trung Duc Le

Keyword(s):

Ethanol Production ◽

Oxygen Demand ◽

Cod Removal ◽

Treated Wastewater ◽

Treatment Processes ◽

Physico Chemical ◽

Biological Methods ◽

Treatment Step ◽

Main Material

The industrial production of ethanol by fermentation using molasses as main material that generates large quantity of wastewater. This wastewater contains high levels of colour and chemical oxygen demand (COD), that may causes serious environmental pollution. Most available treatment processes in Vietnam rely on biological methods, which often fail to treat waste water up to discharge standard. As always, it was reported that quality of treated wastewater could not meet Vietnameses discharge standard. So, it is necessary to improve the treatment efficiency of whole technological process and therefore, supplemental physico-chemical treatment step before biodegradation stage should be the appropriate choice. This study was carried out to assess the effect of coagulation process on decolourization and COD removal in molasses-based ethanol production wastewater using inorganic coaglutant under laboratory conditions. The experimental results showed that the reductions of COD and colour with the utilization of Al2(SO4)3 at pH 9.5 were 83% and 70%, respectively. Mixture FeSO4 – Al2(SO4)3 at pH 8.5 reduced 82% of colour and 70% of COD. With the addition of Polyacrylamide (PAM), the reduction efficiencies of colour, COD and turbidity by FeSO4 – Al2(SO4)3 were 87%, 73.1% and 94.1% correspondingly. It was indicated that PAM significantly reduced the turbidity of wastewater, however it virtually did not increase the efficiencies of colour and COD reduction. Furthermore, the coagulation processes using PAM usually produces a mount of sludge which is hard to be deposited.

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INFLUENCE THE QUENCHING AND TEMPERING ON THE MICROSTRUCTURE, MECHANICAL PROPERTIES AND SURFACE ROUGHNESS, OF MEDIUM CARBON STEEL

THE IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING ◽

10.32852/iqjfmme.vol18.iss1.78 ◽

2018 ◽

Vol 18 (1) ◽

pp. 125-135

Author(s):

Sattar H A Alfatlawi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Surface Roughness ◽

Carbon Steel ◽

Cold Water ◽

Medium Carbon Steel ◽

Medium Carbon ◽

Heating And Cooling ◽

Treatment Processes ◽

Quenching And Tempering

One of ways to improve properties of materials without changing the product shape toobtain the desired engineering applications is heating and cooling under effect of controlledsequence of heat treatment. The main aim of this study was to investigate the effect ofheating and cooling on the surface roughness, microstructure and some selected propertiessuch as the hardness and impact strength of Medium Carbon Steel which treated at differenttypes of heat treatment processes. Heat treatment achieved in this work was respectively,heating, quenching and tempering. The specimens were heated to 850°C and left for 45minutes inside the furnace as a holding time at that temperature, then quenching process wasperformed in four types of quenching media (still air, cold water (2°C), oil and polymersolution), respectively. Thereafter, the samples were tempered at 200°C, 400°C, and 600°Cwith one hour as a soaking time for each temperature, then were all cooled by still air. Whenthe heat treatment process was completed, the surface roughness, hardness, impact strengthand microstructure tests were performed. The results showed a change and clearimprovement of surface roughness, mechanical properties and microstructure afterquenching was achieved, as well as the change that took place due to the increasingtoughness and ductility by reducing of brittleness of samples.

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