Evaluation of Resource recovery Alternatives in South African water (ERASE)

Project summary

Resource recovery from wastewater is a rapidly emerging research area, promoting the development of several technologies that hold the promise to increase the sustainability of process operation in water treatment systems. Different types of organic compounds/acids with industrial relevance can be obtained through controlled fermentation/chain elongation processes. Nutrients, such as phosphorus, can be recovered in various forms for use in agricultural fertilizers. Energy, in the form of heat and electricity, can be extracted from the wastewater to offset the power demands of the treatment facility and move towards carbon neutrality. Cellulose is a major fraction from the incoming organic matter and could be directly recovered and reused.

The ERASE project - Evaluation of Resource recovery Alternatives in South African water Treatment systems - seeks to demonstrate the benefits of transiting from wastewater treatment plants (WWTP) to water resource recovery facilities (WWRF) amongst water utilities in South Africa. Fundamentally, the project will deliver a new generation of engineering tools to simulate resource recovery options in selected South African plants (prior implementation) and to evaluate these novel technologies in line with the objectives of the circular economy paradigm (multi-criteria evaluation + LCA). The ERASE project contributes directly to the Danish Strategic Sector Cooperation program (SSC) in South Africa (i) thematic area 1 (urban water management) and (ii) crosscutting component 1 (water sector research and innovation). The project will deal with important topics such as limiting water waste release, increase water efficiency and improving water quality.

Outputs

First year report
We have accomplished to develop a model library (implemented in a software prototype) focused on extracting valuable compounds from wastewaster (freely distributed) These tools will show to South African environmental engineers the benefits of: 1) promoting the recovery of resources from wastewater instead of just “removing pollutants”, 2) reducing energy needs for wastewater treatment, and consequently reducing greenhouse gas emissions and the risk of climate change, and, 3) finally the optimization of energy production from residual organic material, thus reducing the expenditures derived from plant operation.

We are currently engaged in adapting these models in selected case studies: 1) Cape Flats, 2) ZeeKoegat and 3) Kamasshu. The activities for the forthcoming year will be data analysis and processing, model calibration / validation and scenario analysis suggested by the water utilities. The activities for next year will be focused on sustainability evaluation and communication of results to end users.