1. Paris, 2/10/2003 TOWEF0 - Evaluation of the effect of the IPPC application on the sustainable waste management in textile industries Activities WP6 Davide Mattioli (ENEA PROT IDR) E-Mail: mattioli@bologna.enea.it

2. Treatability tests for reuse Treatability of textile effluents has been tested on laboratory scale membrane pilot plant. In the following, a description on the main issues is given: kEffluents treated kExperimental runs carried out kPreliminary evaluation of feasibility kToxicity tests on concentrates kGeneral conclusions

3. Effluents tested -synthetic fibres

4. Effluents tested -natural fibres

5. Membrane treatability u Laboratory scale tests to select the proper membrane for each effluent. u Several membranes tested (UF, NF and RO) u Treatment trains tested on pilot scale using spiral wound polymeric membranes: UF, NF, UF + NF, UF + RO. u Operational parameters and full permeate characterisation at various level of feed concentration.

6. Effluent/ treatment tested

7. Results UF tests *n.a. : non applicable

8. Results NF tests *n.a. : non applicable

9. Results UF + NF train *n.a. : non applicable

10. Results UF + RO train

11. Toxicity tests Objective of the toxicity tests is the toxicity evaluation of textile wastewater concentrate on activated sludge nitrification process. This evaluation is conducted using the pH-stat titration technique (it consists in the controlled addition of an appropriately diluted solution of a strong acid or a strong base to keep constant the pH of a suspension within which a pH affecting reaction is taking place).

12. MARTINA -the automated titration unit-

13. Output of a pH-stat titration test m(C i ) m(C o )

14. Effluents tested for toxicity kSilk Reactive dyeing (UF+NF) kSilk HT scouring (UF+NF) kCotton Bleaching line (UF+NF) kViscose reactive printed Washing -RPW (NF e (UF+NF))

15. Alimento Conc UF (MW) Conc NF (DK) Perm NF (DK) Rimozione (Alim – Perm) COD tot[gm -3 ]165024102200 COD sol[gm -3 ]165023302200 BOD 5 [gm -3 ]159240229 TOC[gm -3 ]8061175105512484 % TC[gm -3 ]14981805202751466 % IC[gm -3 ]69263097239048 % pH9.50 9.549.47 Conducibilità[mScm -1 ]39.835.937.43317 % Torbidità[NTU]0.4 0.30.63- Assorbanza λ 1 [426nm]2.8133.4313.8600.009100 % λ 2 [558nm]3.9394.0344.2150.009100 % λ 3 [660nm]0.0220.0390.0890.00483 % Results Reactive dyeing

16. Alimento Conc UF (MW) Conc NF (DK) Perm NF (DL) Rimozione (Alim-Perm) COD tot[gm -3 ]26203917890 COD sol[gm -3 ]12842075747 BOD 5 [gm -3 ]644820150 TOC[gm -3 ]4017995222893% TC[gm -3 ]5009006918383% IC[gm -3 ]991011695548% pH8.458.889.28.5 Conducibilità [  Scm -1 ] 12451357276075555% Torbidità[NTU]3.7211.10.392% Assorbanza λ 1 [426nm]0.0220.1040.0110.00291% λ 2 [558nm]0.0100.0570.0060100% λ 3 [660nm]0.0090.0490.0080.00278% Results Bleaching line

17. Results HT scouring

18. Alimento Conc. NF (DL) Perm. NF (DL) Rimozione (Alim-Perm) COD tot[gm -3 ]8784870 COD sol[gm -3 ]8624850 BOD 5 [gm -3 ]345960 TOC[gm -3 ]800244840250% TC[gm -3 ]868.5269043250% IC[gm -3 ]68.52423055% pH9.358.859.57 Conducibilità [  Scm -1 ] 1223467050659% Torbidità[NTU]2.602.100.6675% Assorbanza λ 1 [426nm]0.3932.1600.01297% λ 2 [558nm]0.3301.8390.00699% λ 3 [660nm]0.1530.7910.00498% Results Reactive printed washing (NF)

19. Alimento Conc UF (MW) Conc NF (DL) Perm. NF (DL) Rimozione (Alim-Perm) COD tot[gm -3 ]87811501050760 COD sol[gm -3 ]86211501040750 BOD 5 [gm -3 ]345683174656 TOC[gm -3 ]800977101941249% TC[gm -3 ]8681020124844948% IC[gm -3 ]68432293746% pH9.359.178.539.5 Conducibilità [  Scm -1 ] 122311263230398.867% TorbiditàNTU]2.602.500.850.965% Assorbanza λ 1 [426nm]0.3930.7791.0020.00898% λ 2 [558nm]0.3300.7260.6450.00399% λ 3 [660nm]0.1530.3450.2020.00398_% Results Reactive printed washing (UF+NF)

20. Toxicity test evaluation FeedConc.UFConc.NF EC 50 ml gVSS -1 COD/BOD 5 EC 50 ml gVSS - 1 COD/BOD 5 EC 50 ml gVSS - 1 COD/BOD 5 Dyeing MW+DK 20.910.424.9108.110 HT Scouring MW+DL 138.62.6985.33.047.71.8 Bleaching MW+DL 33.65.6111.94.841.65.9 RPW DL 22.92.5--16.85.1 RPW MW+DL 22.92.514.31.78.26.0

21. Conclusions 1.Membrane treatment tests were performed on 17 different process effluents: The only treatment of UF does not normally assure a quality of the permeates suitable for reuse as feed stream for all the industrial processes, while it can be usable for less exigent factory needs. NF cut-off resulted to be the best compromise between the need of having high flow rates (consequently reducing treatment costs) and good quality permeates. The colour is almost completely removed. The salinity abatement is variable and in some dyeing operation, with high salinity due mainly to mono-valent salts (i.e. reactive dyeing of silk and cotton) the removal was low not allowing the reuse. The removal of organic matter is high, typically 80 - 90%, nevertheless effluents with a high organic content (DOC> 400-500 mg l -1 ) gave permeates normally non reusable.

22. Direct NF treatment was possible only on very diluted effluents (from rinsing operations). The percentages of removals obtained in these cases are lower but sufficient to allow the production of a permeate reusable in any process. In all other cases an UF pre-treatment was necessary. The treatment configuration UF + NF seems in most cases technically and economically feasible except for the polyester double scouring, silk polymer charge and cotton bleaching line which evidenced very low permeate fluxes and/or relevant material accumulation on the membrane surface. RO treatment of the effluent tested always requires an UF pre-treatment and despite the very high removal of contaminants, it resulted to be scarcely promising because of the very low fluxes. Conclusions

23. 2.For a fluidodynamic evaluation, the following parameters have been considered: percentile loss of flow rate passing from water (first characterization) to the effluent (ave. flowrate in the run) percentile loss of flow rate during each run (between initial and final flowrate) percentile loss of water flow rate after the run in reference to the one calculated before (1 st and 2 nd characterization) Based on the data on fluxes, evaluations are possible to obtain a prevision of capital, operation and maintenance costs.

24. 3.Re-utilisation tests of the treated effluents: as reported by LARIANA and CENTEXBEL 4.Toxicity tests showed that: inhibition of UF concentrates, in all cases, is not superior to the one of the feed to the treatment (raw wastewater) concentrates from ‘reactive dyeing’ and ‘reactive printed washing (NF)’ have low bio-degradability and high toxicity; on the contrary, the concentrates from the treatment of ‘HT scouring’ and ‘bleaching line’ have low toxicity and seem to be bio- degradable. Conclusions