Scale-up of low-carbon footprint MAterial Recovery Techniques in existing wastewater treatment PLANTs

The project will prove the feasibility of circular management of urban wastewater and environmental sustainability of the systems and co-benefits of scaling-up water solutions through Life Cycle Assessment and Life Cycle Costing approaches.

Nutrient Recovery

Nitrogen and phosphorus will be recovered from the secondary effluent using ion exchange media. Phosphorus will be removed by adopting a hybrid ion exchange media (HAIX) for phosphorus removal and ammonia will be removed using Mesolite which is a type of zeolite. Both ammonia and phosphate will be recovered using chemicals in order to regenerate the sorption material and recover the nutrients as high added value chemicals of ammonia sulphate and calcium phosphate.

Nutrients will also be recovered as struvite and as sludge which is rich in phosphorus via the treatment of municipal wastewater and sludge reject water. In the first case struvite precipitates with the addition of magnesium and proper pH adjustment. In the second case, enhanced biological phosphorus removal results in the accumulation of high concentrations of phosphorus in sludge. The produced chemicals and the sludge (treated to become P-rich compost) have a high agronomic value and will be applied to land to demonstrate increased crop production.

Ammonium Sulphate

Ammonium Sulphate

Calcium Sulphate

Calcium Sulphate

Struvite

Struvite

SMART-Plant technology platform: approach for integration in existing conventional wastewater treatment plants

SMARTech1 is the key to enable primary cellulose harvesting from medium-large WWTPs. It will apply the primary concentration of wastewater by Salsnes Filter dynamic fine-sieve, which can enable maximal recovery of resources. The Salsnes Filter will separate cellulosic sludge that will be followed by post-processing inside the WWTP. The latter includes a compact sequence of operation unites imported by the paper and food industry to produce clean and marketable cellulose. The cellulosic material will be also provided outside the WWTP for the downstream blending with PHA and processing for final bio-composite production (Downstream SMARTechA).

Read more

SMARTech2a is the key to enable secondary biogas recovery from small-medium municipal WWTP where irregular organic-load peaks often occur. It will apply a secondary anaerobic biofilter with an innovative polymericbased immobilization matrix to treat anaerobically sewage and produce biogas. The system will result in high COD and TSS removal as well as biogas production, providing treated effluent adapted for reuse in agriculture or reclamation after post-treatment. The demo system will have a reaction volume of 25 m3 and will be installed at the municipal WWTP of Karmiel (Israel) to treat 100-120 m3/d of sewage.

Read more

SMARTech2b is the key to enable secondary mainstream energy-efficient resource recovery. It applies the SCEPPHAR system to the mainstream treatment train. It consists of two SBR; one for heterotrophic bacterial growth, and another SBR for autotrophic nitrifiers growth, an interchange vessel and a chemical system for P-recovery as struvite. The integrated system accomplishes enhanced N-removal and P-recovery in municipal WWTP.PHA will be recovered from the anaerobic purge of the SBR. The pilot-scale system will have a reaction volume of 6-8 m3 and will be installed at the Manresa municipal WWTP (Spain) to treat about 10 m3/d of sewage.

Read more

SMARTech3 is the key to enable tertiary recovery of N and P based fertilizer based on ion-exchange processes to remove and recover nutrients from secondary effluents. Two different ion exchange media will be applied which are able to successfully capture/remove ammonia and phosphate from the secondary effluent. To overcome the limited supply chain of the ion exchanging materials, new ion exchange media, manufactured in the UK, will be applied. The aim will be to optimize the regeneration cycles for the nutrient recovery, trying to maintain a high sorption capacity after each regeneration cycle. The system will be applied at the Cranfield municipal WWTP (UK) and will treat approximately 10-60 m3/d.

Read more

SMARTech4a is the key to enable the integration of conventional biogas recovery from sewage sludge with sidestream energy-efficient and compact nitrogen removal and phosphorus recovery. It applies the SCENA system which integrates the following processes: (o) optional upstream concentration of cellulosic sludge, (i) fermentation of sewage sludge and/or cellulosic sludge with alkalisilcates (e.g. wollastonite) to produce propionaterich VFAs as carbon source, and (ii) via nitrite nitrogen and phosphorus removal (by P-bioaccumulation) from sludge reject water using an SBR. In this configuration, nitrogen is removed through the bioprocesses of nitritation/denitritation, and Enhanced Biological Phosphorus removal (EBPR) is accomplished via nitrite through the alternation of anaerobic/anoxic conditions and via oxygen through the alternation of anaerobic/aerobic conditions. The first full scale demo application to treat around 100 m3/d of sludge reject water will be developed in the WWTP of Carbonera (Italy). It will allow the recovery and reuse of 7 kgVFA and 7-8 kg P-rich sludge per capita per year and the savings of more than 50% bioreactor volume and energy consumption from sludge reject water.

Read more

SMARTech4b is the key to enable the integration of the enhanced biogas recovery (by thermal hydrolysis) of sewage sludge with sidestream energy-efficient and compact nitrogen removal and phosphorus recovery. It modify the original SCENA concept to treat the sludge reject water in the Psyttalia WWTP of Athens, which services a population equivalent of 3,500,000 inhabitants. The CAMBI thermal hydrolysis process has been very recently installed to treat 50% of the produced sludge, before this is sent for anaerobic digestion (AD). The integration of CAMBI with anaerobic digestion produces, after dewatering, a reject water stream that has a very high ammonium nitrogen concentration (>1.2 gN/L). Being the sludge hydrolized for biogas production, the SCENA process that will use the primary sludge reject water as partial carbon source to remove nitrogen and hyper-accumulate phosphorus.

Read more

SMARTech5 is the key to enable the integration of conventional biogas recovery from sewage sludge with the energy-efficient nitrogen removal from sludge reject water and the recovery of PHA and struvite. It applies the SCEPPHAR concept, which was conceived as a modified version of SCENA for WWTPs larger than 150 kPE, where PHA recovery is an economically sustainable option. It accounts of the following subprocesses: (i) sewage sludge fermentation under alkaline conditions (pH around 10) to enhance the production of VFAs and release nitrogen and phosphorus in soluble forms (ammonia and phosphate); (ii) solid and liquid separation of the fermentation products and recovery of struvite form the sewage sludge fermentation liquid by the addition of Mg(OH)2 to favour the precipitation; (iii) ammonium conversion to nitrite accomplished in a SBR; (iv) selection of PHA storing biomass in a SBR by the alternation of aerobic feast conditions and followed by anoxic famine conditions for denitritation driven by internally stored PHA as carbon source; (v) PHA accumulation using a fed-batch reactor to maximize the cellular PHA content of the biomass harvested from the selection stage. The system is based on two SBRs for the via-nitrite nitrogen removal coupled with microbial culture enrichment, and storage of PHA in sewage sludge. The pilot-scale system will be tested and validated at WWTP Carbonera (Treviso, Italy).

Read more

  • SMARTech1 is the key to enable primary cellulose harvesting from medium-large WWTPs. It will apply the primary concentration of wastewater by Salsnes Filter dynamic fine-sieve, which can enable maximal recovery of resources. The Salsnes Filter will separate cellulosic sludge that will be followed by post-processing inside the WWTP. The latter includes a compact sequence of operation unites imported by the paper and food industry to produce clean and marketable cellulose. The cellulosic material will be also provided outside the WWTP for the downstream blending with PHA and processing for final bio-composite production (Downstream SMARTechA).

    Read more

  • SMARTech2a is the key to enable secondary biogas recovery from small-medium municipal WWTP where irregular organic-load peaks often occur. It will apply a secondary anaerobic biofilter with an innovative polymericbased immobilization matrix to treat anaerobically sewage and produce biogas. The system will result in high COD and TSS removal as well as biogas production, providing treated effluent adapted for reuse in agriculture or reclamation after post-treatment. The demo system will have a reaction volume of 25 m3 and will be installed at the municipal WWTP of Karmiel (Israel) to treat 100-120 m3/d of sewage.

    Read more

  • SMARTech2b is the key to enable secondary mainstream energy-efficient resource recovery. It applies the SCEPPHAR system to the mainstream treatment train. It consists of two SBR; one for heterotrophic bacterial growth, and another SBR for autotrophic nitrifiers growth, an interchange vessel and a chemical system for P-recovery as struvite. The integrated system accomplishes enhanced N-removal and P-recovery in municipal WWTP.PHA will be recovered from the anaerobic purge of the SBR. The pilot-scale system will have a reaction volume of 6-8 m3 and will be installed at the Manresa municipal WWTP (Spain) to treat about 10 m3/d of sewage.

    Read more

  • SMARTech3 is the key to enable tertiary recovery of N and P based fertilizer based on ion-exchange processes to remove and recover nutrients from secondary effluents. Two different ion exchange media will be applied which are able to successfully capture/remove ammonia and phosphate from the secondary effluent. To overcome the limited supply chain of the ion exchanging materials, new ion exchange media, manufactured in the UK, will be applied. The aim will be to optimize the regeneration cycles for the nutrient recovery, trying to maintain a high sorption capacity after each regeneration cycle. The system will be applied at the Cranfield municipal WWTP (UK) and will treat approximately 10-60 m3/d.

    Read more

  • SMARTech4a is the key to enable the integration of conventional biogas recovery from sewage sludge with sidestream energy-efficient and compact nitrogen removal and phosphorus recovery. It applies the SCENA system which integrates the following processes: (o) optional upstream concentration of cellulosic sludge, (i) fermentation of sewage sludge and/or cellulosic sludge with alkalisilcates (e.g. wollastonite) to produce propionaterich VFAs as carbon source, and (ii) via nitrite nitrogen and phosphorus removal (by P-bioaccumulation) from sludge reject water using an SBR. In this configuration, nitrogen is removed through the bioprocesses of nitritation/denitritation, and Enhanced Biological Phosphorus removal (EBPR) is accomplished via nitrite through the alternation of anaerobic/anoxic conditions and via oxygen through the alternation of anaerobic/aerobic conditions. The first full scale demo application to treat around 100 m3/d of sludge reject water will be developed in the WWTP of Carbonera (Italy). It will allow the recovery and reuse of 7 kgVFA and 7-8 kg P-rich sludge per capita per year and the savings of more than 50% bioreactor volume and energy consumption from sludge reject water.

    Read more

  • SMARTech4b is the key to enable the integration of the enhanced biogas recovery (by thermal hydrolysis) of sewage sludge with sidestream energy-efficient and compact nitrogen removal and phosphorus recovery. It modify the original SCENA concept to treat the sludge reject water in the Psyttalia WWTP of Athens, which services a population equivalent of 3,500,000 inhabitants. The CAMBI thermal hydrolysis process has been very recently installed to treat 50% of the produced sludge, before this is sent for anaerobic digestion (AD). The integration of CAMBI with anaerobic digestion produces, after dewatering, a reject water stream that has a very high ammonium nitrogen concentration (>1.2 gN/L). Being the sludge hydrolized for biogas production, the SCENA process that will use the primary sludge reject water as partial carbon source to remove nitrogen and hyper-accumulate phosphorus.

    Read more

  • SMARTech5 is the key to enable the integration of conventional biogas recovery from sewage sludge with the energy-efficient nitrogen removal from sludge reject water and the recovery of PHA and struvite. It applies the SCEPPHAR concept, which was conceived as a modified version of SCENA for WWTPs larger than 150 kPE, where PHA recovery is an economically sustainable option. It accounts of the following subprocesses: (i) sewage sludge fermentation under alkaline conditions (pH around 10) to enhance the production of VFAs and release nitrogen and phosphorus in soluble forms (ammonia and phosphate); (ii) solid and liquid separation of the fermentation products and recovery of struvite form the sewage sludge fermentation liquid by the addition of Mg(OH)2 to favour the precipitation; (iii) ammonium conversion to nitrite accomplished in a SBR; (iv) selection of PHA storing biomass in a SBR by the alternation of aerobic feast conditions and followed by anoxic famine conditions for denitritation driven by internally stored PHA as carbon source; (v) PHA accumulation using a fed-batch reactor to maximize the cellular PHA content of the biomass harvested from the selection stage. The system is based on two SBRs for the via-nitrite nitrogen removal coupled with microbial culture enrichment, and storage of PHA in sewage sludge. The pilot-scale system will be tested and validated at WWTP Carbonera (Treviso, Italy).

    Read more

    SMART-Plant is a member of the ICT4WATER cluster