Benefits of Advanced Resource Recovery at the Primary Treatment Stage

Transcription

1 Benefits of Advanced Resource Recovery at the Primary Treatment Stage How to Participate Today Audio Modes Listen using Mic & Speakers Or, select Use Telephone and dial the conference (please remember long distance phone charges apply). Submit your questions using the Questions pane. A recording will be available for replay shortly after this webcast. 1

2 Reasons for Primary Treatment Reduce load to secondary treatment Improve energy recovery (carbon management) Savings for the consumer Standard Solution Conventional Primary Clarifier Conventional Clarifier Large Footprint ~5% SS reduction Large area & residence time Odors (expensive to cover) 2

3 Conventional Clarifier Large Footprint ~5% SS reduction Large area & residence time Odors (expensive to cover) Hydrotech Small Footprint 5% to >9% SS reduction Can target removal of TSS, TP, etc. Covered units, short residence time, easy O&M Odors reduced and easier to control FOOTPRINT 3

4 (Footprint) Conventional Clarifier Hydrotech ~1 gpm/sf (~2.5 m 3 /h m 2 ) ~16 gpm/sf (~4 m 3 /h m 2 ) Site Reference: Stavanger, Norway 5, population equivalent (p.e.) 65 MGD (1,25 m 3 /h) Inlet TSS up to 3 mg/l 4

5 Site Reference: Stavanger, Norway Site Reference: Stavanger, Norway 5

6 PERFORMANCE (Performance) Filtration Inlet pumping station Coarse screens Grit chamber Fine screens ( 5 mm) Hydrotech filter ~5% TSS removal (no chemical) Secondary treatment With polymer addition Inlet pumping station Coarse screens Grit chamber Fine screens ( 5 mm) Flocculation Hydrotech filter ~9% TSS removal Secondary treatment Polymer With coagulant & polymer addition Inlet pumping station Coarse screens Grit chamber Fine screens ( 5 mm) Me Coagulation Polymer Flocculation Hydrotech filter ~95% TSS removal Secondary treatment Also P removal 6

7 (Performance) Reference Data: Malmö, Sweden Sjölunda WWTP Discfilter & Drumfilter With and Without chemical addition Inlet TSS up to 8 mg/l (Performance) Disc 4 micron Drum 4 micron Disc 4 (with micron polymer) & polymer Drum 4 (with micron polymer) & polymer 25 5% 75% 2 Effluent SS (mg/l) % Influent SS (mg/l) 7

8 (Performance) TSS outlet (mg/l) % removal 7% removal No chemicals, 4 µm With floc. polymer & 4 µm With coagulant & polymer With coag. & floc. & 4 µm 9% removal TP Removal % removal TSS inlet (mg/l) (Performance) Performance validated by inspection body ISO 172 certified. Claims registered in EU registry of technologies for water treatment (ETV) Without chemicals With polymer addition Daily averages Weekly averages 8

9 (Performance) Reference Site: Lyngby-Taarbæk, Denmark Mölleåverket WWTP Evaluated renovating existing 4 clarifiers vs Hydrotech filters Selected Hydrotech: better efficiency expected in smaller footprint (Performance) 9

10 (Performance) Up to 925 L/s water after coarse screens, and malfunctioning fine screens and sandtrap (influent 25-1 mg-ss/l) Site Reference: Avesta, Sweden Näs WWTP, Startup 21 1 Drumfilter, 2 stage chemical addition Inlet TSS up to 4 mg/l Inlet TP up to 12 mg/l 1

11 (Performance) 5, PE, with chemical pre-treatment upstream Influent (mg/l) Target effluent (mg/l) TSS COD 4 9 TN TP 6 2 CONTROL 11

12 WHY CONTROL CARBON REMOVAL? Minimize aeration cost Chemical dosage cost < savings from reduced aeration Maximize biofuel production, while Stabilizing C/N ratio WHY CONTROL CARBON REMOVAL? 6 5 y = 2.645x + 17 R² =.6962 Effluent COD (mg/l) Effluent COD Turb Linear (Effluent COD Turb) 1 Example: Influent TN (NH4-N) 35 mg/l Desired C/N ration 8:1 for full denitrification using internal C Requires 28 mg/l COD = Effluent turbidity setpoint 45 NTU Remaining carbon = Biofuel Effluent Turbidity (NTU) 12

13 (Control) PI feedback control is 1 year old, well proven technology. Feedforward combined with PI feedback control faster response Microsieve effluent quality not sensitive to flow variations Short retention time in the coagulation and flocculation stage (Control) 13

14 (Control) (Control) 2 ±1% Q 6 Turbidity (NTU) Flow (m³/h), Polymer dose (mg/l) 24/apr 25/apr 26/apr 27/apr Turb. IN (NTU) Turb. OUT (NTU) Setpoint (NTU) Polymer dose (mg/l) Flow (m³/h) 14

15 16/1/218 (Control) Long Term stability! The controller continuously tries to eliminate the control error by adjusting chemical dose. Thus, system is self-stabilizing around the desired setpoint. 35 1% Out of polymer 9% 3 8% Turbiditet (NTU) 25 7% 6% 2 5% 15 4% 3% 1 2% 5 1% % Runninghours (2-2 February) Turb. IN Turb. OUT Axis Title (Control) Polymer dose Turb in 11/mar 12/mar 13/mar 14/mar Polymer dose is daily varying between - 6 mg/l. With feedback control loop, the correct amount is to dosed for desired setpoint and current effluent water quality Not sensitive to variations in influent wastewater chemical reactivity as in pure feed forward control 15/mar Eff turb 16/mar Avg effluent turbidity 5.6 NTU Set point = 5. NTU. PI feedback control works! 15

16 EASY OPERATION & MAINTENANCE (O&M) Panel & Nozzle Inspection/Replacement 1 BW Pump, 1 Drive per unit Durable & Convenient Design 16

17 Questions 17