Water reuse in the food sector: demonstrating cloth filtration as a viable and economic pre-treatment process for R/O membrane filtration, paving the way towards multiple water reuse schemes

Testing facility

Title

Water reuse in the food sector: demonstrating cloth filtration as a viable and economic pre-treatment process for R/O membrane filtration, paving the way towards multiple water reuse schemes

Duration

September 2019 / September 2020

VIDA Challenges

Sustainable agriculture and efficient greenhouse management

Summary

The market for water reuse within the food sector is growing strongly, due to declining availability of good process water. With the high costs related to production and treatment, there is an increasing  demand for robust and economic technologies that can be used in water reuse schemes.

The concept of cloth filtration has already been applied in other countries around the globe for applications such as water reuse, surface water treatment and extensive phosphate removal. The technique uses pile cloth fibre media in cassettes that are placed in a half or fully submerged drum filter. While rotating, suspended solids and other contaminants in the waste water are accumulated on the outside of the fibre media. Meanwhile the treated water flows through the cloth filter media into the center of the drum, from where it is discharged to the next treatment step. Without stopping the filtration, the filter media is automatically cleansed using a backwash process with water or suction cleaning (vacuum cleaner principle).

Within Europe the experiences with cloth filtration in water reuse schemes are limited. Therefore, in this VIDA project, the consortium aims to demonstrate and validate the cloth filtration technique in a relevant and operational food industry environment in the Netherlands. The objective is to see if the     cloth filtration can become a viable and economic alternative for ultrafiltration (U/F), that is often used as a pretreatment process for reverse osmosis (R/O) membrane filtration in a water reuse unit.

To study this innovative application a containerized demo unit (5 m3/h capacity) is used to test our objectives: firstly –  at the demosite WWTP in Leeuwarden – to get familiar with the operational parameters and secondly –  at a food industry company –  to research the performance when operated in relevant and operational food conditions. The performance results are used for the basis of design and economic surveys to determine OPEX and CAPEX and validate the business case.

This application has several advantages compared to other pretreatment steps before a R/O system, like U/F. The cloth filtration technique in combination with coagulation/flocculation could become a game changing technology in the food value chain. Because of the estimated lower CAPEX and OPEX, this technique has the potential to enhance the feasibility of many water reuse business cases. In that way, this innovative technology could become a milestone that contributes to a more sustainable food value chain within the European Union. For society this is increasingly important as the food industry is generally a locally organized business, creating lots of jobs. If the food industry becomes restricted in growth due to the lack of good quality water, management decisions might lead to closing high risk sites.

This project aims to address the policy barriers, experienced by the European small and medium-sized businesses (SMEs) in the food sector, such as the ones focusing on the legislation for water reuse and the ability for SME’s to introduce new technologies that may be adopted for the water reuse schemes.