PURIFAST project:wastewatertreatment andreuse by means of Advanced Processes and evaluation of the environmental and economical impact by LCA and LCC

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1 Enrico Fatarella PURIFAST project:wastewatertreatment andreuse by means of Advanced Processes and evaluation of the environmental and economical impact by LCA and LCC

2 Wastewater Management An Important Target for Textile Industry In average in the EU water consumption is around 32% of water abstraction, since most of abstracted water is not consumed but returned to the water cycle and made available to further uses, after proper treatment or natural purification. Excluding cooling water, the main industrial water users are thechemical industry, the steel and metallurgy industries, the pulp and paper industry and textile industry. Industrial use of water accounts for about 32% of total water abstractions in the EU.

3 Wastewater Management An Important Target for Textile Industry The textile industry is energy-, water-, and chemical-intensive. Within the industry, the majority of energy, water, and chemicals consumed is for wet processing. At least 40 litres of water are required to produce 1 Kilogram of textile, on the average.

4 Wastewater Management An Important Target for Textile Industry The availability of fresh water is reducing all over Europe. European Environmental Agency 2008 Eurostat 2006 WEI > 20%: water resource is under stress WEI > 40 %: severe water stress and unsustainable use of the water resource.

5 Wastewater Reuse An Important Target for Textile Industry Water conservation is the hydrological answer to the problem and certainly water reuse is an important component of water conservation strategies. 1. Recycled Water is an alternative water resource 2. The reduction of environmental impacts by reducing or eliminating wastewater disposal, which results in the preservation of water quality downstream

6 Wastewater Reuse An Important Target for Textile Industry European Legislation forces the Industries to adopt strategies for wastewater management European Directive 61/96 Integrated Pollution Prevention and Control (IPPC) Water Framework Directive (2000/60/EC)

7 Textile Industry Chemical Finishing Chemical finishing has always been an import component of textile processing in recent years the trend to high-tech products has increased the interest and use of chemical finishes(source: Chemical Finishing of Textile) With fibers production currently about 60 M tonnes, about 6 M tonnnes of chemicals auxiliaries are consumed. About 40% of textile auxiliaries are used in finishing

8 Wastewater Reuse An Important Target for Textile Industry Water Framework Directive (2000/60/EC) ANNEX VIII Priority Pollutants List 33 priority substances were selected on the basis of their risk to the aquatic environment or to human health via the aquatic environment.

9 Wastewater Reuse Textile target The major water quality issues for textile production are to ensure that the dyes react properly and that discoloration or staining does not occur. Turbidity, colour, iron and manganese have the potential to cause staining of fabric during production. Hardness adversely affect soaps used in various cleaning processes and can cause durd-like deposits on the textile. Usually soaps are not deposited evenly with hard water, resulting in dyeing irregularities. Hardness may cause precipitation of some dyes and increase in the breakage of silk during reeling and throwing operation(treweek, 1982).

10 Wastewater quality after secondary treatment Case study 1: Textile dyehouse Case study 2: Mixed Municipal Wastewater

11 Wastewater Reuse PURIFAST Approach ULTRAFILTRATION Ultrafiltration is used for the separation of suspended solids, colloids, bacteia and virus. This technique uses membranes with pore size between nm. TECHNIQUE MWCO* (Da) Microflitration >10 5 Ultrafiltration Nanofiltration Reverse osmosis 10 2

12 Wastewater Reuse PURIFAST Project ADVANCED OXIDATION PROCESSES Advanced oxidation processes (AOP) combine ozone (O 3 ), ultraviolet (UV), hydrogen peroxide (H 2 O 2 ); Ultrasonic treatment and/or catalyst for the reduction (removal) of residual organic compounds. All AOP are designed to produce hydroxyl radicals. It is the hydroxyl radicals that act with high efficiency to destroy organic compounds..

13 Wastewater Reuse PURIFAST Project

14 Wastewater Reuse PURIFAST Approach Case study 1: Textile dyehouse King Colour Tintoria Case study 2: Mixed Municipal Wastewater

15 Wastewater quality after tertiary treatment/refinery Case study 1: Textile dyehouse As expected Combined treatment is able to significantly reducing organic pollution load! Inorganics (Sulphates and Chlorides; Salts, etc.) are not affected. Case study 2: Mixed Municipal Wastewater Ozonation is showing the best performances in terms of depollution efficiency. US kinetic is too slow and too much energy is required to runthe US pilot!

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17 LCA assessment Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle This establishes an environmental profile of the system! Goal and Scope definition Purpose, system boundaries, functional unit and assessment criteria Inventory analysis Quantifying environmental interventions (emissions, resource extraction and land use) of a product system under study Impact Assessment Selection of categories Selecting impact categories and their indicators Classification Assigning inventory data to impact categories Normalisation Referring relative magnitude for each impact category of a product systme Weighting Aggregation category indicator results according to their reative importance INTERPRETATION

18 LCA assessment Case Study 1 Conventional process: Dyeing(including washing) + CAS Dyeing process is an high polluting process: up to 99.8% of the total impact is due to this process SimaPRO software RECIPE Europe H/H Data Collection relay with Ecoinvent2.1

19 Conventional process:dyeing(including washing) + CAS + UF + US Prato, June14 th, 2012 LCA assessment Case Study 1 A significant increase in the Impact is achieved by using US technology; the impact of the US treatment is 24%; a 2 magnitude order higher than the Ozonation treatment! Conventional process: Dyeing (including washing) + CAS + UF + O 3 No significant differences are recorded because of the high impact of the Dyeing process (in particular in terms of energy consumption more than 60%)

20 LCA assessment Case Study 1 Comparison:Dyeing+ CAS vs.dyeing+ CAS + UF + O 3 No significant benefit induced by the implementation of the combined UF + O 3 process because of the high impact of the dyeing process Comparison: CAS vs. CAS + UF + O 3

21 Comparison: CAS vs. CAS + UF + O 3 Prato, June14 th, 2012 LCA assessment Case Study 1 Considering the overall wastewater treatment chain (the discharge of the effluent in the Carpi MWWTP has been considered) the reuse induce a significant benefits for all the impact categories. Comparison: CAS + MWWTP vs. CAS + UF + O 3

22 LCA assessment Case Study 2 Conventional treatment (including Refinery of part of the treated wastewater) Electricity is the main factor that influences the Environmental impact of the MWWTP (38%). Moreover Ozone production is severely affected the impact of the process considering the low reaction yield of the ozone generator (7%). PURIFAST treatment (including Refinery by combined UF+US) US treatment is responsible for the 97% of the overall environmental impact of the combined US+UF Refinery treatment! The main parameters contributing to the ecopoint are the huge usage of chemicals (in particular H 2 O 2-44%; and HNO 3 35%) and energy (16%)

23 LCA assessment Case Study 2 Comparison: Conventional vs. Purifast(Ozonation) Since Wastewater reuse is already promote by conventional refinery a lower benefit is expected at MWWTP by the implementation of the combined UF and AOP treatment even if it can promote the reduction of the Carbon footrprint(- 5%) and of the fossil depletion!

24 Life Cycle Costing Case study 1: Textile dyehouse /m /m /m King Tintoria Colour Case study 2: Textile dyehouse /m /m