Case studies

Stavanger and Hamar case

Fertiliser and soil improver by wastewater resource recovery, Hamar and Stavanger, Norway

Utility – industry symbiosis
HIAS IKS and IVAR IKS are two inter-municipal companies that treat a total load of 570 000 pe municipal and industrial wastewater. The WWTPs are in the process of converting from chemical phosphorus removal to enhanced biological phosphorus removal (EBPR). HIAS is implementing an innovative continuous moving bed biofilm reactor (MBBR) process in collaboration with their partner, the SME Hias How2O. Biogas is produced by digestion of the sludge. Pilot trials with struvite precipitation for P-recovery have been performed and will be implemented in full scale to recover 18-30 tons P/year. Sirkula is a state-owned company in the supply chain producing biosolids from various organic waste including wastewater sludge, and responsible for collection of household waste and operation of several recycling stations for handling of source separated waste fractions. At IVAR, there is co-digestion of food waste and sludge, and the biogas is adjusted and mixed with natural gas in a mixed energy grid for the region. The SME HØST AS (earlier Norsk Jordforbedring AS) produces pelletized organic fertilizer from the residual sludge.

Objective
Demonstrate solutions for: i) Phosphorus recycling to agriculture based on innovative continuous MBBR process for EBPR; ii) Production of both organic and balanced inorganic fertilizers; iii) Increased support to the gas-based regional energy grid.

Key stakeholders and partners
Sirkula, HØST, Grødaland industry park, Felleskjøpet (agriculture supplier), SINTEF and NTNU.

Stavanger and Hamar case – innovative actions
HIAS is implementing an innovative continuous MBBR process for enhanced biological phosphorus removal (EBPR) in collaboration with their commercial partner Hias How2O. A sludge processing line for recovery of P from the EBPR sludge will be established. Biogas is produced by digestion of the sludge. Pilot trials with struvite precipitation for P-recovery have been performed and will be implemented in full scale to recover 18-30 tons P/year, corresponding to 200-350 ton struvite/year at HIAS IKS. Recovered struvite will be processed to obtain a quality required for application as a fertiliser. Sirkula will address new pathways for distribution of the product to the agricultural sector. IVAR IKS has invested in new plants during the recent years for wastewater treatment, sludge treatment, handling and treatment of solid organic waste. All processes are designed and operated for maximizing reuse of energy and nutrients. At IVAR IKS, process solutions to maximize the impact of available carbon for energy production, minimize operational problems of unintended struvite formation and harvest the nutrients for industrial use will be demonstrated. The demonstrations will show how to establish an optimized resources recovery considering different local conditions.

Outcomes
The goal is to reach the total phosphorus discharge limits without using any chemicals for precipitation. The existing production of organic fertilizers and inorganic fertilizers in the Minorga process will be improved by use of P and N from the treatment plants. P-recovery (> 50%) by struvite precipitation will be demonstrated. Struvite, biomass and organic waste streams will contribute to production of a peat-free
biosolid (or organic fertilizer) in compliance with upcoming revised regulations and appropriate to meet the needs of agriculture and produced soil.

Presentation of the norwegian cases
Presentation of the norwegian cases

Sicily case

Reuse of wastewater for irrigation and production of slow-release fertilizers in agricultural industry, Sicily, Italy

Utility – industry symbiosis
The wastewater treatment plants (WWTPs) in Corleone and Marineo have special features for water reuse and nutrient recovery. Corleone has a membrane system and a distribution network for water reuse by local agriculture. Marineo WWTP will be devoted to material recovery, by implementing a process line for the PHA production /extraction as well as the installation of final filters filled with Biochar and zeolites for nutrients adsorption. The Corleone WWTP will be devoted to water reuse in agriculture where an experimental field trial will be conducted for assessment of the field interactions among water-soil-plants. A new industry consortium will be constituted to utilize the full potential of these reuse facilities.

Objective
Demonstrate solutions for: i) Reduction of greenhouse gas (GHG) emissions by improving the wastewater treatment process; ii) Recovery of nitrogen and phosphorus from wastewater by biochar and zeolite filters; iii) Reuse of the recovered nutrients (as slow-release fertilisers) and sewage sludge (as amendments) for agricultural and forest purposes; iv) Extraction of polyhydroxyalkanoat
es (PHA) from mixed microbial cultures. v) Reuse of treated wastewater for irrigation in agricultural and possibly in public gardens of urban areas.

Key stakeholders and partners
Local and regional agri-food producers, farms and their associations, biochar technology owners, bioplastic industry; i.e. Mugavero Teresa s.a.s and Marineo and Corleone Municipalities, AMAP SPA, Università degli studi di Palermo.

Sicily case – innovative actions
Nitrogen and phosphorous from wastewater will be recovered by using innovative filters filled with special adsorbents such as biochar and zeolite. Both materials have already been explored as soil amendments and nutrient absorbents. Indeed, due to their high surface area, porosity and presence of charges, both adsorbents are very efficient in adsorbing nutrients improving also soil physical, chemical and biochemical properties. Nutrient-enriched biochar and zeolite from wastewater treatment will be added directly to agricultural soils as slow-release fertilisers. PHA extraction will be done by an innovative protocol, which employs switchable anionic surfactant ammonium laurate. GHG from WWTPs will be reduced by both experimental and mathematical modelling activities. The sewage sludge will be disposed of, after a preliminary treatment, in agriculture and forest. Reuse of treated wastewater for irrigation will be evaluated. The demonstrations will be performed both in full scale WWTPs and pilot plants. Local industries related to water reuse as well as fertiliser production will be part of the project fostering the application of the circular economy concept.

Outcomes
Creation of a new CE value chain with a new market of biomaterials derived from wastewater treatment. Demonstration of best practices for this as basis for further implementation that offer advantages for the local economy connected to wastewater reuse.

Presentation of the Sicily case
Presentation of the Sicily case

Accra case

Reuse of wastewater for urban agriculture, Accra, Ghana

Utility – industry symbiosis
The Sewerage Systems Ghana Limited (SSGL) signed a public-private partnership management contract with the Ministry of Local Government to operate the Mudor Treatment Plant. The plant treats wastewater from Accra, the capital of Ghana, and has a capacity of 18 000 m3/day. The case will facilitate utilisation of treated wastewater for urban agriculture through the Farmers Organization Network of Ghana, as the industry representative, by means of value chain development. Furthermore, since biochar is a resource produced from treated sludge, the action will also promote the adoption of biochar for burning in the textile and chemical industries in Ghana.

Objective
Development and demonstration of a value chain for use of treated wastewater for urban agriculture and promotion of biochar usage as substitute for wood fuel used in the kilns of textile and chemical industries, which can reduce emissions and reduce deforestation through reduction in dependence on wood fuel.

Key stakeholders and partners
Sewerage Systems Ghana Limited, Ministry of Food and Agriculture, Ministry of Local Government and Rural Development, the Accra Metropolitan Assembly, Farmers Organizations Network of Ghana, The association of private water distributors, Water Resources Commission of Ghana, Association of Ghana Industries, CSIR Science and Technology Policy Research Institute & Water Research Institute.

Accra case – innovative actions
Use of wastewater from the Mudor Treatment Plant for urban agriculture after polishing treatment for additional particle removal and disinfection will be demonstrated in pilot scale. Addressing the institutional framework will be another key component of the case study while assessing and ensuring the quality of wastewater is within acceptable limits for irrigation. In addition, finding mechanisms to improve and maintain positive perceptions of treated wastewater and therefore acceptance of crops grown from treated wastewater resources would be imperative to the patronage of any business model developed for the wastewater value chain in Ghana. Through the Farmer Organisations’ Network of Ghana, a value chain that supports the adoption of treated wastewater for urban agriculture will be promoted. In addition, a value chain to promote use of biochar as replacement for wood fuel in kilns in the textile and chemical industries will be developed. These value chains will be relevant also for the Czech and Italian cases.

Outcomes
A primary outcome is to reduce pressure on the amount of surface water resources with the secondary outcome of supporting Ghana Government’s planting for food and jobs policy and creating jobs for the urban youth. Another primary outcome is to reduce the amount of wood fuel used in kilns for burning in the textile and chemical industries through improved recovery and dissemination of biochar to these industries.

Presentation of the Accra case
Presentation of the Accra case

Prague case

Reuse of wastewater for greening of urban areas, Prague, Czech Republic

Utility – industry symbiosis
The new water line (NWL) of the Prague WWTP is located on a Vltava river island in the middle of the city's green area close to the Prague botanical garden, Prague zoo and the biggest Prague recreational area – Stromovka Park. The NWL is located inside a concrete containment to protect the plant from floods. The roof of the containment is covered with soil where grass, bushes and trees will be planted to create a kind of park that also includes grey-green solutions for urban development supplied by Storm Aqua, an SME partner in WIDER UPTAKE.

Objective
Demonstrate safe use of treated effluent for irrigation purposes in grey-green solutions for urban development with reasonable water transportation expenses.

Key stakeholders and partners
City of Prague, Prague botanical garden, Prague zoo, Prague services, Storm Aqua, Czech Technical University and The University of Chemistry and Technology Prague.

Prague case – innovative actions
The activity will demonstrate the feasibility of reusing wastewater in an urban setting after polishing treatment. This will include UV disinfection to be evaluated according to the bacterial quality parameters defined in the proposal of EU regulation for wastewater reuse from May 2018. Micro- and nanofiltration membranes for removal of residual concentrations of suspended solids will be demonstrated. If the water quality analyses indicate problems with reused water salinity, the experiments will be extended to include reverse osmosis. Advanced oxidation processes and sorption will be piloted for removal of pharmaceuticals and hormones. An initial evaluation has indicated that use of ozonation followed by active carbon sorption may be an efficient treatment process for these compounds. Polished wastewater will be used for irrigation of pilot scale grey-green solutions for urban development. Demonstrating the reliability of wastewater reuse for such systems will enable this as an essential element in sustainable urban water management and lead to impacts on the national/international legislation.

Outcomes
The key outcomes will be optimized and functional systems for reuse of treated wastewater to improve the microclimate of adjacent city districts, dramatically decrease demand for expensive tap water for urban irrigation, street washing and other use by the city during the summer (decreasing the effects of city thermal islands, which is a new phenomenon in Prague).

Presentation of the Prague case
Presentation of the Prague case

Amsterdam case

Production of new bio-composite material by water resource recovery, Amsterdam, Netherlands

Utility – industry symbiosis
Waternet is a major utility responsible for the water and wastewater management in Amsterdam and its surroundings. Waternet and the industry SME partner, NPSP, have succeeded in producing the prototype of a new biocomposite material made from resources recovered from the whole water cycle but several issues remain to be addressed before this material can be offered to the markets.

Objective
This unique case study will explore the production and applications e.g. construction materials in park benches and river/canal bank protection solutions, of a new biocomposite material made by recovering resources from drinking water treatment (calcite), wastewater treatment (cellulose fibres) and surface water management (water plants), all glued together using a biobased resin.

Key stakeholders and partners
Water utilities providing source material (WATERNET), biocomposite material technology developers (NPSP), manufacturing companies (that will produce end products from new material), supply and distribution chain, end users (companies in construction and traffic industries and general public), TU Delft.

Amsterdam case – innovative actions
NPSP and WATNL are interested in the production of a new bio-composite material for several reasons including a contribution to circular economy, its own finances and reduction of greenhouse gas emissions resulting in increased climate change resilience. These two partners have already succeeded in producing the prototype bio-composite material, but several challenges remain before it can be offered to the market. These include optimizing the proportions of key ingredients, dealing with potential health risks due to reuse of wastewater fibres, understanding better the resource efficiency and related costs and benefits of a new material by performing life cycle and metabolism type analysis, collecting the evidence that new material can compete with traditional materials and exploring market opportunities and new business models. All this will be done in collaboration with TU Delft and other project partners. The new material will be demonstrated on a range of prototype products.

Outcomes
The key outcome will be an optimized, functional, safe and sustainable new bio-composite material ready for mass production.

Presentation of the Amsterdam case
Presentation of the Amsterdam case
Presentation in Dutch
Presentation in Dutch