Periodic Reporting for period 1 - Waste2Fresh (Smart innovative system for recycling wastewater and creating closed loops in textile manufacturing industrial processes)
Okres sprawozdawczy: 2020-12-01 do 2022-05-31
Objective: The overall objective of Waste2Fresh is to develop and demonstrate (to TRL 7) a closed loop recycling system for the dye wastewater from textile manufacturing factories such as the denim ERAK factory. Waste2Fresh system will integrate novel catalytic degradation approaches with highly selective separation and extraction techniques to deliver a closed loop system that assures near-zero discharge, reduces current use of freshwater resources and considerably increases the recovery of water, energy and other resources (organics, salts and heavy metals). The system will therefore increase resource and water efficiency and ultimately lead to considerable environmental gains weighted against EU and global environmental footprints. The Waste2Fresh solution fits into Zero Liquid Discharge (ZLD) - a wastewater management strategy worth 5.44Bn € and expected to reach 8.16Bn € by 2025, growing at a CAGR of 5.5% over 2019-2025.
Once the synthesis and color removal parameters were optimized, a prototype of a batch reactor was designed based on the deliverable D4.2. The design contemplated the incorporation in the reactor of a perforated grid-type basket where the nanofique is loaded so that it is in continuous contact with the dye solution. the design also contemplated the inclusion of an inlet and an outlet valve to simulate the entrance of the textile wastewater into the reactor and the subsequent exit of the treated water. Successful color removal tests were performed on 100 ppm indigo carmine solutions at 1 L scale in the reactor using aeration instead of mechanical agitation. A series of experiments were conducted to find the optimal conditions for the batch prototype to be operational. Once optimized, the technical team tested the process on a prototype reactor (5 L/h) located at the Konya Technical University. The operating conditions for color removal with Nanofique were optimized using aqueous solutions of indigo carmine as model wastewater. However, for the actual testing of the prototype, real wastewater samples from the textile industry supplied by ERAK (Denim Manufacturing and Development Center, Turkey) were used following the optimal operating conditions of the experimental design.
Overview of results:
A new synthetic procedure was validated to obtain nanofique in fewer steps and with better performance than traditional synthesis. Furthermore, this new method was applied in the scale-up synthesis of nanofique up to 1 Kg.
Critical variables such as temperature, hydrogen peroxide concentration, and nanofique loading were found to be the most important parameters for the color removal capability of the nanofique system according to the experimental results carried out at a laboratory scale as well as on a small pilot scale.
Color removal of real textile wastewater samples from the ERAK industry was performed successfully in a small pilot reactor at Konya Technical University removing up to 90% of the color in a 30 L wastewater volume scale.
Key costs for obtaining nanofique material were analyzed. It was found that it is possible to synthesize nanofique with low-cost commercial grade reagents without losing catalytic performance. Also, synthetic steps were eliminated as it was shown that they do not affect the material obtaining and catalytic activity.
• Development of a new nanofique material that allows the degradation of dyes from the textile industry in a neutral pH range with the aim of improving the catalytic process of color degradation as well as reducing operational costs by not making necessary the acidification of the wastewater. This objective will be carried out by immobilizing other nanoparticles, e.g. copper-iron bimetallic nanoparticles, on the surface of the fique fibers and finally evaluate its catalytic performance in pH conditions above 4.