Improved protein hydrolysis monitoring for biological wastewater treatment

Improved protein hydrolysis monitoring for biological wastewater treatment Pieter Van Gaelen Arenberg castle, February 19 th 2020 1

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Wastewater? Wastewater stream Domestic (daily life) Industry 3

Biological wastewater treatment – what? CO 2 C N in organic matter P N 2 H 2 S, N 2 O Microbes convert organic matter Microbial sludge (C, N, P) → post-treatment → landfill 4

Biological wastewater treatment - why? water discharge Clean lakes, rivers, groundwater → healthy ecosystems → healthy drinking water 5

Protein hydrolysis – what? Protein Casein Albumin Gelatin + H 2 O Enzyme X Peptide A + Peptide B An enzymatic reaction inside a microbial floc 6

Protein hydrolysis – so what? High solids wastewaters Solid waste digestion Wastewater treatment at low T (Benelux) 20 16 12 8 4 0 J F M A M J J A S O N D → Monitoring is required for stable performance high conversion rates R&D purposes …. 7

Protein hydrolysis monitoring – the old-school approach Biomass sample Precipitant TCA Lab incubation Subsample Freeze Centrifuge 1, …. . n Supernatant Abs ≈ product formation Labelled protein Azocasein Low cost Limited data per sample Low-throughput Prone to interference 8

Protein hydrolysis monitoring – the modern approach = BO Y DIP FL Y FL = BODIP Hydrolysis Intramolecularly quenched milk protein Fluorescent peptides 9

Protein hydrolysis monitoring - the modern approach Biomass sample Lab incubation On-line fluorescence ≈ product formation Labelled protein ‘High’ cost High sampling frequency High throughput Low interference 10

The modern approach in real life Municipal wastewater treatment facility Leuven (BE) Biological treatment Municipal wastewater Screens Sand trap Grease removal Sedimentation Water discharge Compressed air Sludge recycle Sludge waste 11

Protein hydrolysis starts in the sewer system 4000 3000 Protein hydrolytic activity (products min-1 mg. VS-1) 2000 1000 0 0 1 2 Wastewater 3 4 Biological treatment 5 6 Treated water 12

The activity profile throughout the plant is time dependent August 2019 4000 3000 Protein hydrolytic activity (products min-1 mg. VS-1) 2000 1000 0 0 1 2 Wastewater 3 4 5 Biological treatment 6 Treated water 13

The activity profile throughout the plant is time dependent September 2019 4000 3000 Protein hydrolytic activity (products min-1 mg. VS-1) 2000 1000 0 0 1 2 Wastewater 3 4 Biological treatment 5 6 Treated water 14

The activity profile throughout the plant is time dependent October 2019 4000 3000 Protein hydrolytic activity (products min-1 mg. VS-1) 2000 1000 0 0 1 2 Wastewater 3 4 Biological treatment 5 6 Treated water 15

From conventional aerobic treatment systems… Municipal wastewater treatment facility Leuven (BE) Biological treatment Municipal wastewater Screens Sand trap Grease removal Sedimentation Water discharge Compressed air Sludge recycle Sludge waste 16

…. . to high-rate alternatives Municipal wastewater treatment facility Breda (NL) Sand trap FOG removal Municipal wastewater Screens Sedimentation High-rate tank X 6+1 X 1 Sludge recycle Effluent recirculation Sludge waste Low-rate tank Sedimentation Effluent discharge X 3+1 X 6+3 Sludge recycle Sludge waste 17

Protein hydrolysis starts in the sewer system (bis) Protein hydrolytic activity (products min-1 mg. VS-1) Influent High-rate tank Low-rate tank 18

Individual biological tanks are homogeneous Protein hydrolytic activity (products min-1 mg. VS-1) High-rate tank Low-rate tank 19

Protein hydrolysis is associated to sludge flocs Sedimentation Protein hydrolytic activity (products min-1 mg. VS-1) = floating sludge in sedimentation 20

Take home messages Protein hydrolysis is a crucial step in several processes → YOU? need MONITORING Protein hydrolysis is a floc-associated reaction Protein hydrolysis starts in our sewer system 21

We have only just started exploring Alternative reactor designs Other substrates Process conditions (An)aerobic granules Biofilms Novel designs Gelatin Albumin (BSA) Starch Cellulose Lipids (micro)aeration p. H Metal ions Metabolic disruptors 22

Contact info Leuven Chem&Tech (200 F) https: //cit. kuleuven. be/creas With technical assistance by: pieter. vangaelen@kuleuven. be https: //www. linkedin. com/in/pietervangaelen/ @CREa. S_kuleuven 23