Project: Heavy metal monitoring device to improve the environmental safety of wastewater emissions and sewage sludge quality

Heavy metals, including cadmium, chromium, copper, nickel, lead and zinc, are acutely toxic to humans at high concentrations, and of even greater concern to public health, is the possible exposure to low concentrations over long time periods – i.e. chronic exposure. Significant quantity of the heavy metal pollution is generated in industrial processes where it is emitted to the urban wastewater collection system after some pre-treatment phases. Controlled collection and treatment of wastewater are therefore critical to limit contaminant releases to the environment. However the collection is notoriously difficult to monitor and control effectively. In addition, unidentified and illegal sources may contribute as much as 30-60 % of the total metal load entering the wastewater treatment system , and strategies aimed at controlling pollutant discharges can only focus on sources which can be identified and quantified. In wastewater treatment processes a significant amount of heavy metals are retained in the sewage sludge, while the rest is emitted to the water environment. Application of sewage sludge to agricultural land is the largest outlet for its beneficial use, and this is consistent with EC policy on waste recycling, recovery and use. The Sewage Sludge Directive 86/278/EEC sets upper limits for limits of trace metals in municipal sewerage sludge for use on agricultural land, and revision of the Directive is expected to lead to even more stringent limits; however some Northern and Accession countries are already applying stricter regulations. This is a critical issue due to the increasing amount of sludge produced (from 5.5M tonnes of dry matter in 1992, to 9M tonnes in 2005), and the fact that other alternatives (incineration and landfill) are not generally considered environmentally acceptable._x000D_The most widespread method for determination of metal concentrations in wastewater is via grab sampling and subsequent laboratory analysis. This method is both costly, which limits its application, and typically involves a 24 hour turn around time, which means that pollution events can be missed, or detected too late. Metals should be measured both at the inlet flow to wastewater treatment plants, and at the source of potential discharges. _x000D__x000D_The commercial objective of the project is to deliver a cost effective, low COtenance, on-line instrument for the real-time determination of heavy metal concentrations in wastewater to the market in under 2 years. _x000D__x000D_Electrolyte Cathode Atmospheric Glow Discharge (ECAGD) is a proven analytical technique developed by AQUACON, who will take a leading role in this project. AQUACON has demonstrated sub-ppm detection limit performance for Zn, Cd, Cu, Cr, Ni, Pb and other heavy metals in water. ECAGD has the unique advantages of requiring little or no sample preparation, and accepts “dirty” samples containing organic content, oils, fats and suspended matter – i.e. it is highly suited to on-line analysis of metals in wastewater. In conjunction with project Ps, project aims are: to identify key requirements, development of high performance, robust industrial prototype, and evaluate the prototype in industrial wastewater applications._x000D__x000D_The Consortium was built up by four innovative SMEs in order to bring to the market ECAGD application for wastewater monitoring. The patent covering the ECAGD technique is owned by AQUACON and their expertise in this field is indispensable. FKK has been chosen as CO P for their experience in EU funded projects, and was selected on the basis of their experience in the field of plasma technology and measurement technologies as well as power electronics. They have co-operational agreements with the Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences and The Bay Zoltán Foundation where they will develop the discharge cell and spectrometer unit together with AQUACON. CRIC has been chosen for their experience in EU funded projects, and for their expertise in the development of online, on-site monitoring devices and complex electromechanical systems, having vast experience in process development and machine design from earlier biosensor projects. KOBIT is recognised for its knowhow in the field of data transmission systems and dedicated software design.

Acronym GreenWWater (Reference Number: 4371)
Duration 01/10/2008 - 30/09/2010
Project Topic Heavy metal emissions in wastewaters put a high risk to the environment and to public health. There is a real need to develop an on-site, low-cost heavy metal monitoring instrument which is able to operate in raw wastewaters. The electrolyte cathode glow discharge technique is our proposed solution.
Project Results
(after finalisation)
Industrial wastewater, contaminated by heavy metals, migrates to surface and underground water sources. Heavy metals are toxic even at low concentrations. GreenWWater project is aimed to develop an on-line, low COtenance, on-site, continuous monitoring device for the detection of heavy metals in wastewater. After formulating the market needs by a questionnaire survey, the individual parts of the device were developed. _x000D__x000D_The CO features of the measurement device are: a flow through measuring cell for 10 ml per minute liquid flow rate, measure range for Cd concentration in the range of 0.1 - 10 mg/l and for Zn, Cu, Ni and Pb levels in the range of 1 – 100 mg/l, frequency is automatically adapted to the pollution event detection: the higher the observed concentration the higher the sampling frequency ranging from 2 to 6 sampling/hour. _x000D_The different parts of the prototype were developed individually in the first step: _x000D_(i) A sample treatment unit tailored for the special composition (fat and oil emulsions) of wastewaters was developed, it contains a self-cleaning rotating slit-filter unit, developed in the framework of this project. Further, the preparation of an analytical sample and automatic adjustment of the pH was carried out. _x000D_(ii) A so called discharge cell was developed. It is a flow though cell, in which a glow discharge plasma is generated and acts as emitter of light with specific wavelength determined by heavy metal contamination. The optimal geometry and also high voltage power supply was developed within the project framework. _x000D_(iii) A spectrometer and its optical connection system was defined and constructed according to a design optimized carefully. _x000D__x000D_These parts were integrated into one unit. The electric and hydraulic connections were designed to be compact and to ensure smooth working conditions. Parallel with physical integration a control panel, software and hardware specifications for operation and PC communication was developed. The control of the system is divided into two parts: the microcontroller with embedded software, that is built in the measurement unit and a PC based software, which also acts as an interface for user communication. _x000D__x000D_The system prototype was tested in two different fields: in the South-Pest Wastewater Treatment Plant between 13 and 16 November 2010 and between 13 and 16January 2011 in Barcelona, Spain. During these trials the monitor was working autonomously for more than 72 hours. The results of the GreenWWater monitoring were in accordance with parallel conventional laboratory tests. Calibration was good. Spiking with internal standard solution was successful, resolution and detection limit of the GreenWWater monitor was acceptable.
Network Eurostars
Call Eurostars Cut-Off 1

Project partner

Number Name Role Country
4 Invention and Research Centre Services Ltd. Coordinator Hungary
4 Aqua-Concorde Water LLC Partner Hungary
4 Krakowski Osrodek Badan i Technologii Sp. z o.o. Partner Poland
4 Ateknea Solutions Catalonia Partner Spain