Action A.1: Status analysis in the targeted area
This preparatory action included the benchmarking of common routines in wastewater handling in fruit industry. Information was collected through the distribution of questionnaires and personal audits to representative fruit-packaging and fruit processing units in Greece and Spain. The questionnaire included general information (water load used, quantity of fruits which are processed annually, recording of annual use of post-harvest pesticides and other chemicals) and data on wastewater handling and routes of disposal. Key information was the amount of spent liquid and solid waste produced per ton of processed fruit, the duration of the annual processing cycle, the cost of disposal per ton of fruit and per year and possible differences in the handling practices depending on the commodity. Apart from pre-filled topics the stakeholders were prompted to share their standpoint on relevant aspects of water management and safe disposal of wastewater. The last sequence of questions aimed at stimulating possible future interest and, if possible, commitment to future activities.
Deliverables
D-A1.1: List of food packaging/processing industries
Three lists of packaging/processing industries from Greece (2) and Spain (1) are provided in the format of Excel files.
Delivery Date: 31/01/2019
D-A1.2: Report of the baseline situation regarding water use and wastewater management in fruit-packaging and fruit-processing industry
In the context of this preparatory action, a survey was launched to gain insight into wastewater recycling and disposal practices in fruit-packaging/processing industry in Greece and Spain. An extensive list of packaging/processing industries in the two target States was initially prepared (Deliverable D-A1.1). A draft questionnaire was distributed internally and was reviewed by all Beneficiaries. It was agreed that the questionnaire will be concise and include information on the industry/processed commodities, the water use in the facilities, the amount of wastewater produced, and the wastewater disposal/reuse/recovery practices employed.
The initial call for participation was done in March-May through the Google Forms web application, and a reminder was dispatched approximately two weeks later via e-mail. Invitations were sent to selected members of agro-food industry and replies were received by early June 2019. As a follow-up action, a line of communication with industry associations (Greek Food & Drink Industry chamber in Greece and COEXPHAL in Spain) was launched. The questionnaire was reviewed by the Sympraxis team. Personal communication with executive officers of selected agro-industries in both States was initiated. The LIFE PureAgroH2O workshop, which was hosted in Athens in mid-January of 2020, was used as an opportunity to establish personal contact with representatives from the Greek food industry and gather information related to the objectives of this Action.
The enterprises in Spain were described as packaging or processing or mixed processing/packaging. Replies from Greece mainly concerned the packaging industry (80% of the responses). The size of the enterprises was typically small or medium, with a high variability in terms of the annual tonnage within each State. The type of common operation routine is variable and usually includes a combination of more than one process, washing being the most prevalent in the two States. The water volume which is used annually ranges from 60-400,000/year (usually groundwater or municipal water or both). A number of different chemicals are used in the raw material washing and/or processing. This includes mainly disinfectants (40-60%), although other chemicals are also used. A total amount of effluent wastewater of >10000 m3/year accounts for 41% and 50% of enterprises in Spain and Greece, respectively. The effluent water used for washing or processing is typically not recycled in the facilities. In enterprises for which water is not reclaimed in Greece, wastewater is disposed on sewage treatment plant (41%), or an external contractor is involved in the procedure (35%). On the contrary, in Spain the direct discharge of effluents to the sewer seems to be the preferable discharge routine (67%). There seems to be a significant difference in the cost of water disposal between enterprises. Thirteen of the industries (33% of total responses) declared their interest in innovative purification/reclamation technology, which may be considered an early indication of potential interest of a considerable fraction of the Agri-industry for the PNFR technology.
Delivery Date: 01/04/2019
Action A.2: Conceptual process design (CPD) and optimisation
CPD studies had as target to implement the mathematical description of the PNFR process and other competitive technologies (reference cases) and to establish the mass and energy balance equations, incorporating Key Performance Indicators (KPIs) of the process (system productivity per time and volume, pressure drop, liquid velocity, water permeability, solute rejection efficiency, and kinetics of organic molecules photodegradation). The developed CPD tools allowed assessing the PNFR for the removal of a multitude of organic and inorganic pollutants, bacteria and pathogenic organisms in representative applications. The Fruit & Vegetables Processing industry was a priority, under the needs of the preparatory actions for process design and optimisation. NCSRD conducted fast screening tests in the available (patented) lab scale PNFR reactor using wastewater feeds that were provided by ZAGORIN. To support the replicability and transferability of the novel PNFR technology, NCSRD constructed a pre-pilot scale replicate of the existing lab scale PNFR (1.5 m³ /day) which was sent at UAL (Spain) and placed in CITRICOS del Andarax S.A. industry to perform experimental testing using wastewater from juices, gazpacho, soups and vegetable creams processing.
Deliverables
D-A2.1: Configurations of the PNFR technology, in an industrial operation
The Preparatory Phase of LIFEPureAgroH2O included the Action A2 related to the Conceptual Process Design (CPD) of the PNFR technology and its optimization, with the targets to achieve energy mitigation and reduction of the capital and operational cost (Sub-Action A2.1), along with benchmarking the novel PNFR technology against state of the art technologies such as adsorption on powdered and granular activated carbons (PAC & GAC), ozonolysis, as well as nanofiltration and photocatalysis when applied as stand-alone processes (Sub Action A2.2). The CPD study pertains to the preparation of a preliminary flow-diagram of the overall process, including the boundaries of the wastewater treatment system and the way to retrofit the fruit washing process at ZAGORIN with the PNFR technology. Accordingly, an estimation of the dimensions of each component of the process has been implemented based on the targets for daily water production and purity. This encompassed: (i) the dimensions and number of PNFR reactor modules; materials of construction and thickness of stainless-steel flanges and tubular cell to withstand the required operation pressure, (ii) definition of the most effective pretreatment process of the wastewater effluent, upstream the PNFR reactor modules, to allow for uninterrupted operation and minimize the need for frequent membranes’ washing, along with prohibiting the permanent fouling of the membranes, (iii) number and dimensions of multi-channeled ceramic monoliths in each PNFR module, number and dimensions of cylindrical channels, length of glazed ends of the monoliths, number and dimensions of the porous hollow fibers embedding TiO2 nanoparticles, (iv) design and engineering of reactor’s internals, (v) design, engineering, construction, and operation of a small prototype, including just one set of the reactors’ internals to test all the components that will be used for the leak tight sealing of all active materials, (vi) design of the irradiation system including the number and power of the UV lamps, as well as, the number and power of the HP-LEDs and the way of their coupling with the side glowing optical fibers. (vii) relative position of the active components and artificial light sources to safeguard effective irradiation of the multitude of photocatalytic surfaces existing inside the PNFR reactor module.
These activities took place from July until the end of 2018 and have concluded into two important deliverables:
- D-A2.1: Configurations of the PNFR technology, in industrial operation.
- D-A2.2: Design and technical performance of the integrated process-design of the PNFR technology in the FVP industry.
As mentioned in the detailed technical description of the project’s actions, CPD studies necessitate the knowledge of several Key Performance Indicators (KPIs) of the process and properties of the photocatalytic nanofiltration membranes. These included the system productivity per time and volume, the pressure drop, the liquid velocity, the water permeability, the solute rejection efficiency, the surface charge, the kinetics of organic molecules photodegradation and their dependency on the feed composition, the intermediate products, the presence of inorganic cations and anions (NO3-, ammonium, heavy metal cations), the pH, the temperature and the irradiation intensity.
Therefore, the CPD studies had to be assisted by experimental data under realistic conditions at the “pre-pilot” level, exploiting the testing facilities committed to the project by NCSRD.
Delivery Date: 01/02/2019
D-A2.2: Design and technical performance of the integrated process design of the PNFR technology in the FVP industry
This Deliverable pertains to a description of the process concept of the PNFR wastewater treatment technology and includes a process flow diagram, mass and energy balances, short-cut equipment design, definition of control and safety issues, preliminary piping and instrument diagrams and overall performance data and energetic features. This Deliverable constitutes a significant input for the environmental and technoeconomic analysis (B4) and supports the activity B1.1, as it contains all data needed to conduct the Front-End Engineering Design (FEED) and detailed engineering and deliver the blueprints of the process.
Delivery Date: 01/02/2019
For further information please contact Dr Emilia Markellou (e.markellou@bpi.gr)