Action B.1: Construction of the upscaled PNFR system Action Progress: The implementation phase of the project started with Action B1 related to the Construction of the upscaled PNFR system. This action encompasses all the activities which are necessary in order to safeguard the fluent, on-site operation of the entire PNFR process, having as starting point the CPD output and the preliminary design and optimization studies of Action A2. CPD resulted to the optimized flow sheeting of the entire process and the optimized draft designs and dimensioning of the PNFR reactor. Based on these, a detailed FEED study was implemented, leading to the definition of the exact specifications of the several components and equipment of the entire process and the preparation and announcement of the required tender packages or the preparation and signing of the required contracts for their procurement. B1.1 – Detailed engineering design In the detailed engineering tasks we have developed the piping, flange and instrument diagrams released for construction (including construction details for finishing the tips of the optical fibers and interfacing with the high power UV LEDs), the detailed piping drawings, the detailed drawings related to instrumentation and electrical facilities and we have performed cost and schedule control. As an output of this task the blueprints of the PNFR prototypes has been prepared and delivered in solid works platform. B1.2 – Procurement of consumables and equipment for membrane and reactor development. A Public Tender, Contracts and Direct commissioning were carried out to purchase the necessary consumables and equipment. These actions are in progress. B1.3 – Preparation of the site and integration of the reactor. Plot of the overall process at ZAGORIN:
Front End Engineering Design (FEED) and detailed engineering have been performed based on the output of the CPD studies (Action A2.1) and the implementation of optimization studies for the PNFR reactor and the overall process. Optimization studies were conducted via the process simulation tool developed with the gPROMS Process Builder platform.
The FEED included:
A) Mechanical and electrical data sheets.
B) Process and utility piping and elaboration of the main piping layouts.
C) Meters to the power supply system and measuring instruments (flow meters, pressure transducers, on-line conductivity and on-line TOC analyzer) interfaced with the automatic control system of the reactor and the application of data logging and control that has been developed on the LabView platform.
D) Definition of the appropriate control points for sampling and analysis of the pesticides.
The place for the installation of the process at ZAGORIN is decided. A plot of the overall process including the four reactor modules, the CFS tank, the pumps, the piping, and the tanks for collecting the clean water is prepared by NCSRD in scale of (1:41.7) and send to ZAGORIN together with the estimated load of each component and the expected power requirement for operation of the entire process.
Pictures from the process of making the monolithic substrates to be used for the development of photocatalytic nanofiltration membranes. The blue edges indicate the glazing that ensures the sealing / isolation between the filtrate compartment and the feed compartment within the PNFR reactor.
Action B.2: PNFR operational procedures for application in ZAGORIN Action Progress: Having the output of the FEED and detailed engineering study it was possible to implement a HAZOP (Hazard and Operability Analysis) study of the PNFR reactor and the overall process, concentrating on how the design will cope with abnormal conditions and identify all possible deviations from the design intent, with undesirable effects on labor and the environment. The HAZOP study covered all the required scope for the design, installation, operation and maintenance of the PNFR water facility under development and classified the risks to those raising a significant safety concern, (which have the potential for a serious or major incident), and those raising substantial operating concerns, along with trying to reduce each risk to “as low as reasonably practical.” Moreover, we have tried to avoid the creation of a too complex and too instrumented water treatment system which may be judged to be as unsafe and problematic as the lack of protection and control. We have selected the optimum number of protection layers for a relatively simple and robust system. Currently,
PNFR is operating in Spain. Assays with different types of water, different
pesticides used as model microcontaminants and different concentrations of
pesticide are being carried out to study these parameters on PNFR performance.
Regarding the full-scale PNFR, the process of installation at ZAGORIN premises
is ongoing and the Reactor is entering the phase of initial operation tests. Deliverable B2.1: HAZOP study of the pilot process Demokritos had to conduct the Hazard and Operability Analysis (HAZOP analysis) of the PNFR reactor and the overall process, integrated to the pome fruits screening/rinsing process. In this action a safe standard operation procedure both in terms of maintaining the operability of the process along with ensuring labor and environmental safety should be identified and evaluated for on-site conditions. Achievements: Having the output of the FEED and detailed engineering study it was possible to implement the HAZOP study of the PNFR reactor and the overall process, concentrating on how the design will cope with abnormal conditions and identify all possible deviations from the design intent, with undesirable effects on the operability, and on the labor and the environment. Thus, the HAZOP study covered all the required scope for the design, installation, operation and maintenance of the PNFR water facility under development and classified the risks to those raising a significant safety concern, (which have the potential for a serious or major incident), and those raising substantial operating concerns, along with trying to reduce each risk to “as low as reasonably practical.” Thus, we have studied the effects of irradiation, temperature, flow in the PNFR and of the liquid level in the tanks and the reactor module, along with the quality of the waste water in terms of its pH, the presence of interfering substances and the existence oxidants/electron acceptors and charged species. Working this way, we have decided which of these parameters rise significant operability and safety concerns and concluded to the design of a simple monitoring system for the most important of the process parameters. The output of this work was a description of the process monitoring locations and the definition of guidewords as well as a final schedule on how these guidewords are used in conjunction with the process parameters, the causes, the consequences, and the recommendations. For more info, please contact Dr E. Markellou (e.markellou@bpi.gr).
Action B.3: Analytical procedures Action Progress: In the context of the implementation of the project, micropollutants; e.g. residues of pesticides, and their metabolites, heavy metals, additionally to physicochemical (hardness, suspended solids, TOC, pH, conductivity, COD), microbiological & toxicological parameters were all determined in water samples (influent), wastewater (effluent) together with sludge, collected before, during, and at the end of the washing process in the stage production of ‘’washing- sorting on-site’’ at the premises of the Agricultural Cooperative of Zagora, “ZAGORIN”. Deliverable B3.1: Report on Chemical, Toxicological and Microbiological analyses of treated waste water samples from Greece In four discrete sampling periods (from mid-September 2018 up to the end of September 2019), water and wastewater samples were collected from 9 defined sampling points. All samples were analysed by standard and validated analytical methods for their physicochemical, microbiological and toxicological characteristics. Physicochemical parameters were defined, and the worst -case scenario was considered in Action A2. Heavy metals were quantified in water and sludge samples by applying validated analytical methods on ICP-MS. For microbiological analyses in water samples the following parameters or specific pathogens were tested according to standard ISO methods: Total Viable Count (TVC) at 22°C and 37°C (ISO 6222:1999), Intestinal Enterococci (ISO 7899:2000), Coliforms and Escherichia coli (ISO 9308-1:2014), Clostridium perfrigens (& spores) (ISO 14189:2013) and Pseudomonas aeruginosa (ISO 16266:2006). As to investigate the potential occurrence of pesticide residues in water, samples from several strategically selected points were collected and analyzed with an LOQ of 0.01 mg/L using an in-house multi-residue method for 250 compounds. Pesticides in the sludge were analyzed by a wide scope multi-residue analytical method of a third-party laboratory (external contractor) and by a BPI in-house multi-residue validated analytical method focused on active substances which are relevant for apple cultivation. The toxicity of collected water samples has been assessed on non-target aquatic indicator organisms i.e. freshwater crustacean Daphnia magna and non-pathogenic luminescent bacterium Vibrio fischeri (Microtox©). The Action B3.1 has been implemented successfully. Deliverable B3.2: Report on Chemical, Toxicological and Microbiological analyses of treate waste water samples from Spain The results described in this document are included in the context of the preparatory Actions A.2.1: Conceptual process design (CPD) and optimization (2nd part) and B.3: Analytical procedures, in order to contribute to the transferability and replicability on the performance of the photocatalytic/nanofiltration reactor (PNFR) in an agro-food industry in Spain. For more info, please contact Dr E. Markellou (e.markellou@bpi.gr).
The total microbiological load (bacterial and fungal) on all wastewater samples will be determined to identify possible threats (i.e human and plant pathogens) for the posterior use/fate of those effluents in field irrigation and/or cleaning purposes at the packaging unit premises. Microbia will be determined via classic microbiological (culture-dependent) diagnostic methods, microscopical observation and colony enumeration following standard characterization and quantification protocols.
Acute toxicity assays will be performed on wastewater samples using as indicator organisms the crustacean Daphnia magna and the bacterium Vibrio fisheri. In parallel, analytical measurement of the levels of pesticides or other contaminants on the same samples will allow the establishment of correlations between exposure and effects. These results will be used for the evaluation of the PNFR for wastewater treatment.
Some of micropollutants may cause toxic effects on environmental organisms or humans, and thus legal maximum levels for their concentration on different matrices have already been established by the European Commission.
A key objective of the project, through the application of the novel system PNFR (photocatalytic/nanofiltration reactor) is the reduction/elimination of any environmental micropollutants, and toxicity of the wastewater (15m3 per day), with a view to a further use of this effluent water, either recycled back to the washing unit or even reused, e.g. for irrigation.
Pre-control of water quality by detection of its physicochemical, microbiological & toxicological characteristics was essential for the definition of the guideline in order to set the baseline conditions, aiming to enhance and optimize the set up-operation of the reactor, based on the characteristics of the system ‘’reactor-inlet water’’ (e.g. pre-treatment of water to prevent hardness and fouling of the membranes).
Overall, water at all sampling locations, covering the whole water line from springs, water collection tanks, washing tanks to the final end-of-the-pipe wastewater effluent in the washing water collection tanks, was tested from mid-September 2018 up to the beginning of October 2019, in 4 incremental batch samplings periods of apple washing. For the monitoring of the target environmental micropollutants, before and while reactor operation, standard and validated analytical methods are applied by using state-of-the-art analytical methods (GC-MS/MS, LC-MS/MS, ICP-MS).
Furthermore, acute toxicity tests of the collected water samples are also carried out on indicator organisms (e.g. Daphnia magna and Vibrio fishery), which are sensitive species to the presence of pesticides, heavy metals, and other environmental pollutants. In addition, this toxicity assessment is in line with the requirements of the current legislation framework for the evaluation of pesticides, and biocides.
The analytical measurements, and the toxicity bioassays will be carried out, in order to compare the influent and effluent water samples from the reactor operation, during the project time. These results will be used to evaluate the overall efficiency of the reactor.
For PNFR implementation, the effluent of the wastewater treatment plant was chosen as feeding water to the reactor, due to the interest of reusing this reclaimed water for agricultural irrigation.
Apart from the physicochemical characterization of the different sampling points, pesticide analyses and microbiological analyses were performed to complete water characterization.
Action B.4: Evaluation and economic analysis of the implementation of the PNFR treatment system
A second activity is to benchmark innovative membranes vs conventional ones. Thus, except from the enhanced performance achieved by the PNFR technology implementing the novel membranes, another target of paramount importance is to define the environmental impact from the production of novel membranes. Life cycle assessment (LCA) will be used on this purpose, to characterise “cradle to grave” environmental impacts related with the production phase of the novel membranes. The LCA analysis will be performed by NCSRD based on the ISO14040 standard following the Impact Assessment methodology defined by the United Nations Environment Programme and will be carried out using the SimaPro 7.0 software.