Struvia Technology for Phosphorus Recovery. o Re-Water Braunschweig November 2015

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1 Struvia Technology for Phosphorus Recovery o Re-Water Braunschweig November

2 Resourcing the World o Vision of circular economy o Sous-titre o Waste and Waste Water are resources

3 Veolia Water Technoloy Serving municipal and industrial clients worldwide, by: Delivering engineering and turnkey design & build projects Providing client-tailored water treatment solutions and associated services With employees creating 2.3 billion revenue Municipal market revenue 40% Industrial market revenue 60% 3

4 Veolia Water Technologies in Germany Based in Celle, Leipzig, Bayreuth, Ratingen and Bremen More than 470 employees for engineering, management and execution of projects in Drinking and Process Water and Waste Water Treatment 85 Mio Sales 474 employees 4

5 Circular Economy in Braunschweig and P N Energy Crop Energy Agriculture Biogas plant N and P Fertilizer makers Treated water Lagoons Raw water WWTP Cities 5

6 Nutrients from Waste Water Removal of Nitrogen (N) and Phosphorus (P) is an essential task for a WWTP oremoval Sous-titre of N & P needs tank volume, energy and chemicals Is there a way to recycle a useful product?

7 Pre-selected technologies Nutrient recovery requests 2 steps: Phosphorus can be precipitated easily as Struvite (MAP) Nitrogen can be recovered after air-stripping in a column as di-ammonia-sulfate Both products can be recycled as raw material for fertilizers Centrate Chemicals Struvite P-precipitation Chemical /Air Air- Stripping Di-Ammonia Sulfate Inlet wwtp Chemical The idea is : local reuse of the nutrients which were transformed into added value material 7

8 Technologies for P-precipitation Precipitation as Fe- or Al-salts Almost no availability as fertilizer Calcium-Phosphate High ph needed, utilization as fertilizer is limited Struvite precipitation in sludge Struvite has to be washed out and collected separately, efficiency is limited Struvite precipitation from centrate in bigger pellets Crunching needed before mixing with other fertilizers or for improved plant availability Struvite precipitation from centrate in smaller crystals / granules Can be mixed for producing organic fertilizer Has quick plant availability Can be molded as mineral fertilizer, free size selection 8

9 Struvite What is Struvite? Struvite is a crystalic mineral and is made of Ammonia, Phosphate and Magnesium (MAP) Chemical formula: (NH4)Mg(PO4) + 6 H2O Releases slowly into the soil The good biological availability for the plants covers a longer period Struvite decomposes at higher temperature (drying, storing) How can it be produced? Wastewater contains Ammonia und Phosphate but small amounts of Magnesium Reaction takes place at ph and reduces ph After precipitation Struvite can aggregate as small granules Struvite granules can be easily separated and dried.9

10 Struvia Plant

11 Scheme of the Struvia Plant Sludge Centrifuges WWTP Agricultural Use ❶Reject Water ❷Chemicals ❹ Effluent ❻ Wet Struvite Fertilizer Production ❺ Laboratory ❸ Reactor with Lamella Separator (Turboflo ) ❼ Struvite 11

12 Struvia - Pilot Plant Conditions Centrate was stored from digested sludge dewatering 1st Period: Centrate from Summer 2014 ph SS N-NH4 P-PO4 Mg Ca 8,5 <50 mg/l 1200 mg/l 340 mg/l <2 mg/l 20 mg/l 2nd Periode: Centrate from February 2015 ph SS N-NH4 P-PO4. Mg Ca 8,1 ca.60 mg/l mg/l 420 mg/l 2-3 mg/l 25 mg/l 1 extra week: with enriched SS Adjustment of ph with NaOH HRT: (30 ), 45 und 60 SRT 2 3 days Struvite concentrations g/l 12

13 Struvia - produced Struvite Production rate : about 2-3 kg Struvite/m³ influent (Depending on PO 4 -P in centrate) Product in size and shape similar to sand Granular, µm diameter particles Drying in bags reach nearly 90 % after a few days Fresh Struvite Granules Drying bags 13

14 Struvia - results of Pilot Trials Typical effluent results under normal operation conditions P-PO 4 N-NH 4 Mg Ca < 20 mg/l PO 4 -P removal 90 % Reduced by 200 mg/l mg/l mg/l NH 4 -N removal about 15 % No Ca-Phosphate precipitation Remarks on Pilot trials High PO 4 -P concentrations allow effective precipitation and high removal rate Stable operation of automated process Failure in MgCl 2 dosing pumps shows clear effect on performance Quick start-up and shut down within a few minutes 14

15 Detailed results 15

16 Struvia - Benefits Compact Design Based on well proven Veolia Turboflo Technology Dosing of Chemicals, precipitation and separation in one reactor Simple process design Reduced costs for invest and operation Small footprint increases storage capacity No recycle stream needed for gaining high capture rate Produced Struvite High purity Can be granulated and/or mixed with organic fertilizers Very good plant availability Proven results from other applications Effluent from Wet Oxidation (WWTP Brussels-Nord) Treatment of centrates in various applications Effluent of anaerobic digestion of a starch factory 16

17 Helsingør Southcoast WWTP PE, N-removal, Bio-P 17

18 The Helsingør case Tender requirements Design basis 250 mg/l P in reject 60 m 3 /d 15 kg P/d (PO 4 -P) Recovery 90 % 110 kg/day Struvite product Installation in basement Max. height 3.5 m entire plant must be within the marked area Two 60 m 3 reject water tanks to be used as buffer volumes for flow equalization 18

19 Helsingør Struvia plant Proposed Layout Reactor height: 2.7 m Reactor diameter: 1.4 m Start-up: February Draining bags. 1/week) Reactor Chemicals dosing/storage 19

20 Sustainable Water Treatment Solutions Veolia Water Technologies in Germany Resourcing the world