| EUREKA 2983 TEXTILWET |  |
Title: CONSTRUCTED WETLANDS FOR TREATING TEXTILE DYES
Duration: 2002 - 2005Partners:
| Slovenia: Limnos d.o.o. Ljubljana University of Maribor / Faculty of Mechanical Engineering |
www.limnos.si www.uni-mb.si |
| Croatia: University of Zagreb / Faculty of Textile Technologies | www.ttf.hr |
| Greece: Elkede Tech & Design Center SA Atena | www.elkede.gr |
| Romania: Laceca SA Bucuresti Dorobantul SA Ploiesti |
www.dorobantul.ro |
Summary:
Development Of The Use Of A Combination Of Chemical Reagents And Constructed Wetlands To De-Colour Textile Wastewaters Which Currently Cause Environmental And Financial Problems.
Textile effluents present complex and coloured wastewaters: they are not
adequately treated in conventional wastewater treatment plants and therefore
seriously endanger the environment. Different technologies, all highly costly,
are being proposed, but textile wastewaters are basically an unsolved problem.
Due to the strict environmental legislation and high cost of wastewater
treatment, the project activities are oriented towards the development of
efficient dye-bath effluents decolouration processes. The main objective
of the proposed project is the synthesis of existing partial solutions and
new know-how in an innovative manner that will offer a cost-beneficial solution
for efficient treatment. In the project, simple and low cost alternative
techniques for de-colouring offered by a Constructed Wetland (CW) will be
tested and optimised in combination with conventional techniques in order
to offer a reasonable solution to the textile industry. The CW technique
will be developed using textile mill wastewaters from the producers of cellulose
fibres and their blends with polyester fibres, because these branches represent
a worldwide significant production plant. Only recently, CW technology has
been considered as an option for the treatment of industrial wastewater.
Industrial wastewaters most amenable to this type of treatment modality
include landfill leachate, pulp and paper, petroleum refinery discharges
and some chemical manufacturing wastes. Therefore, treatment of dyed industrial
wastewater (e.g. textile) with CW represents a highly innovative approach.
CW are capable of treating textile wastewaters containing a wide range of
chemicals by processes such as absorption and bacterial breakdown, chemical
oxidation, adsorption onto the bed matrix and sedimentation. They have basic
properties to control textile pollutants including high organic carbon to
bind contaminants to sediments; high microbial diversity to biodegrade organic
pollutants; and both aerobic and anaerobic environments to ensure that potentially
toxic organic intermediaries are completely degraded. Based on the high
efficiency of treatment of textile wastewater with the pilot CW (results
of the pilot CW in Ajdovscina, SLOVENIA 1989-1992), we assume that the combination
of chemical reagents and CW could offer an efficient and cost-effective
solution for wastewater treatment in the textile industry. Keywords: textile,
wastewater, constructed wetland.
The main aim of the project is to develop an efficient technology for textile wastewater treatment. Major research and development needs to be directed at refining our understanding of dye and toxic substances transformation, immobilisation and other pollutant processing mechanisms and the application of this knowledge to the development of advanced construction CW design in the combination of chemical additives. The theoretical understanding to date of the chemical, microbial and hydrodynamic relationships will be reviewed in terms of the design, operation and maintenance of these systems. The CW model and pilots will be started-up to assess hydraulic and pollution loading, dye removal kinetics, and selection and comparison of wastewater treatment processes based upon cost will be applied to CW issues and effectiveness. The project will be implemented through technological and technical tasks:
1. Database of textile wastewaters and their specifics.
2. Definition of characteristics of dyes and their dynamics within CW (qualitative and quantitative analyses of total wastewaters from storage tanks and within CW). 3. Selection of chemical additives that are compatible with biological processes in CW (reduction and substitution of ecological hazardous dyes).
4. Define synergistic processes of contaminants and by-products.
5. Construction, re-construction and preparation of CW model and pilot plants.
6. Start-up of the system, checking correct operation of the control regulation equipment and technological equipment for monitoring.
7. Gathering the data for the hydrodynamic model (the quantity of water, the direction of the flow) and for the quantity model (mathematical model of chemical changes of water).
8. Monitoring of the efficiency of the CW performance according to concentration and mass loading difference between inflow and outflow.
9. Evaluation of results (the effect of variations in (1) dimensions (depth, width, length), (2) plant species, (3) substrates (natural, artificial with high adsorption levels), (4) hydraulic and pollution loading of CW, (5) climate, (6) chemical additives).
10. Optimisation of CW long-term performance (changing substrata, plants, hydraulic and pollution loads, selection of different chemical additives).
11. Cost-benefit analyses for different practical approaches.
12. Implementation of results (effective and efficient management of the project within the set deadlines and available resources will ensure continuation of the project) and dissemination by appropriate channels to all target groups within textile industries will be organised.
Market Application and Exploitation
The total annual world production of fibres in 2001 was approximately 50 million tons and is expected to rise to 75 million tons by 2010. The total world consumption of dyes in the textile industry in 2001 was 0,6 million tons and it is forecasted to increase by 5% annually. Synthetic fibres, on which the project is focused, comprise more than half of the total fibre consumption and are expected to grow to 64% of the total by 2010. A similar situation is found with cellulose fibres, the second focus of the project: these represent more than 40% of yearly consumption. Based on this it could be assumed that the market possibilities for an efficient textile wastewater treatment technique are enormous. The most important benefit of marketing the proposed technology throughout Europe is pollution control and cost reduction in textile industries. Therefore the innovative use of CW can result in a technology that not only meets regulatory requirements, but also is often more cost-effective in the long term. In addition, CW is aesthetically pleasing, which provides a positive ancillary benefit to private industry.
Link: www.eureka.be Contact: ccti@cco.ro