\documentclass[english,german]{scrartcl}
\usepackage[latin1]{inputenc}
\usepackage{geometry}
\geometry{verbose,a4paper,tmargin=1.75cm,bmargin=2cm,lmargin=2cm,rmargin=2cm,headheight=0.8cm,headsep=0.5cm,footskip=0.5cm}
\usepackage{babel}
\usepackage{url}
\urlstyle{same}
\newcommand\email{\begingroup \urlstyle{same}\Url}\usepackage{graphicx}
\usepackage{units}
\usepackage{tabularx}
\usepackage{wasysym} % enable use of \permil instead of \textperthousand
\usepackage{marvosym}
\usepackage{arabtex}
\usepackage{hyphenat}
\usepackage{booktabs}
\usepackage{mdwlist}
\renewcommand{\thefootnote}{\relax}
\usepackage{index}
\newindex{key}{kdx}{knd}{Keywords}
\newindex{author}{idx}{ind}{Authors}
\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\usepackage{ifpdf}
\ifpdf
%\usepackage[activate]{pdfcprot}
%\usepackage[owner=Tapioka, print=true, copy=true, edit=false, annotate=false,set]{pdfcrypt}
%encryption: not supported any more (since pdftex 1.10)
\usepackage[pdftex]{thumbpdf}
\usepackage[pdftex]{hyperref}
\hypersetup{pdftitle={Biochar Filtration of Wastewater for Sustainable Nutrient Re"=use and Safer Food Production in West Africa},pdfauthor={Korbinian Kätzl, Maximilian Dichtl, Manfred Lübken, Christoph Steiner, Eric Nartey, Samuel Adiku, Gordana Kranjac-Berisavljevic, George Nyarko, Marc Wichern},pdfsubject={Tropentag 2016: Abstract},pdfkeywords={Biochar, BMBF-GlobE, multi-stage filtration, safer food production, UrbanFoodPlus, water reuse},pdfpagemode=None,colorlinks=true}
\else
\usepackage{ae}
\usepackage{textcomp}
\fi
\begin{document}
\ifpdf
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2016.jpg}}}
\else
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2016.eps}}}
\fi
\hfill
\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 18-21, 2016, Vienna, Austria}}\\[1ex] \Large{``Solidarity in a competing world ---\\fair use of resources''\\[2ex]}}
\hspace{0.1cm}
\begin{center}
\Large{\textbf{Biochar Filtration of Wastewater for Sustainable Nutrient Re"=use and Safer Food Production in West Africa\footnote{\textbf{Contact Address:} Korbinian Kätzl, Ruhr-Universität Bochum, Inst. of Urban Water Management and Environmental Engineering, Universitätsstr. 150, 44780~Bochum, Germany, \mbox{e-mail}: \email{korbinian.kaetzl@rub.de}}\\[0.8ex]}}
\normalsize{\textsc{Korbinian Kätzl$^{1}$, Maximilian Dichtl$^{1}$, Manfred Lübken$^{1}$, Christoph Steiner$^{2}$, Eric Nartey$^{3}$, Samuel Adiku$^{3}$, Gordana Kranjac-Berisavljevic$^{4}$, George Nyarko$^{4}$, Marc Wichern$^{1}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Ruhr-Universität Bochum, Inst. of Urban Water Management and Environmental Engineering, Germany}}}
\item[]{\small{\textit{$^{2}$University of Kassel, Organic Plant Production and Agroecosystems Research in the Tropics and Subtropics, Germany}}}
\item[]{\small{\textit{$^{3}$University of Ghana, Department of Soil Science, Ghana}}}
\item[]{\small{\textit{$^{4}$University for Development Studies, Fac. of Agronomy, Ghana}}}
\end{itemize*}
\index[author]{Kätzl, Korbinian}
\index[author]{Dichtl, Maximilian}
\index[author]{Lübken, Manfred}
\index[author]{Steiner, Christoph}
\index[author]{Nartey, Eric}
\index[author]{Adiku, Samuel}
\index[author]{Kranjac-Berisavljevic, Gordana}
\index[author]{Nyarko, George}
\index[author]{Wichern, Marc}
\begin{center}
\vspace{1.1cm}
\textbf{Abstract}
\begin{abstract}
\normalsize{
Wastewater reuse could help to reduce the pressure from global water scarcity, especially in arid and semi"=arid regions. Efficient and cheap water treatment technologies need to be developed, particularly in low"=income countries where wastewater treatment is often lacking. Slow sand filtration (SSF) is a proper, efficient and well known technology to reduce the amount of pathogens and turbidity. However, an efficient use of SSF requires low water turbidity and suspended solids to prevent rapid filter clogging. This may be achieved by upflow roughing filters (RF). 



The focus of this study was the development and operation of a multi"=stage filtration in Tamale (Ghana) for the production of safer irrigation water for urban agriculture in West Africa. The pilot plant consists of an upflow roughing filter for wastewater pre"=treatment, and a downstream gravity or slow sand filter. In two treatment lines, charred (biochar) and uncharred (further declared as feedstock) corn cobs for RF and rice husks for SSF were used to compare different, locally available filter materials. Biochar was produced in low"=cost gasifier. Samples of influent and effluent of filters were taken periodically according to a predefined sampling interval and analysed for fecal indicator bacteria (FIB) \textit{E.~coli} and intestinal enterococci, using colony"=forming units (CFU). Additionally, physico"=chemical parameters (e.g. turbidity, chemical oxygen demand (COD), total nitrogen (N) and phosphorous (P)) were measured.



FIB concentration of raw wastewater was in the range of 2.2x10\textsuperscript{5} to 3x10\textsuperscript{7} CFU 100ml\textsuperscript{-1}. Mean removal rates of FIB were in the range of 2 to 3 log10 units. These results are in line with other published results. While biochar filters were able to remove up to \mbox{90\,\%} of COD, feedstock filters removed less than \mbox{60\,\%}. Average effluent turbidity of biochar filters were below 10 NTU and around 21 NTU for feedstock filters (raw wastewater: 15 to 230 NTU). Due to anaerobic conditions, low removal rates of N and P were observed and treated water could be used as fertiliser. Over the entire experiment, biochar filter performed notably better than feedstock filter and filter effluent is expected to be suitable for drip irrigation.



}

\vspace{0.5cm}
\end{abstract}
\end{center}
\noindent \textbf{Keywords:} Biochar, BMBF-GlobE, multi"=stage filtration, safer food production, UrbanFoodPlus, water reuse
\index[key]{Biochar}
\index[key]{BMBF-GlobE}
\index[key]{Multi"=stage filtration}
\index[key]{Safer food production}
\index[key]{UrbanFoodPlus}
\index[key]{Water!reuse}
\end{document}
