key sectors served - ciwem...kima 1 - egypt roughing mbbr prior to as mbbr ahead of the existing as...

MBBR Technology:-

A cost effective solution for upgrading existing Waste water Treatment Works

Bruno Bigot

1. What is MBBR & How does it work?

2. Different MBBR configurations for upgrading existing WwTW

3. Q&A

Agenda

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• Combining the advantages of

suspended growth and biofilm

technologies

• The core of the process is the biofilm

carrier elements made from

polyethylene with a density slightly below

that of water

• These are designed to provide a large

protected surface for the bacteria

culture

• The biofilm carrier elements are kept

suspended in the water by air from the

diffusers in the aerobic reactors and by

means of a mixer in the anoxic reactors

• HYBAS combines Biofilm & activated

sludge

MBBR = Moving Bed Biofilm Reactor

Hybas = Hybrid Activated Sludge

What is MBBR?

Biofilm carrier elements

Aeration/mixer system Retention sieves

1% Plastic – 99% Know How

3 Key Elements

The Media

Aeration/Mixing Systems

Aerobic reactor sieves Anoxic reactor sieves

The Retention Sieves

Rectangular covered concrete reactors

Circular Steel Reactors (Bolted or Welded)

Circular fiber glass reactors

Rectangular/Circular open concrete reactors

Reactors – new or existing

MBBR – Key Features & Benefits

• Very compact with strong ability to accept high loads

• Simple operation

• Robust biofilm process, recovers fast from acute toxicity and pH-shocks

• No clogging of reactors

• No sludge return – no sludge bulking

• Low loading on the sludge separation stage

• Flexibility for reactor shape – existing tanks or basins may be used

• The carrier elements can easily be pumped in and out of the reactor if desired

MBBR as sole biotreatment

MBBR as pre-treatment

MBBR as post-treatment

MBBR in activated sludge (HYBAS/IFAS)

Liquor Treatment - ANITAMox

Different Configurations

Swansea Bay WwTW, AS into MBBR

Swansea Bay WwTWUpgrade of Activated Sludge

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• Existing AS plant within a building – 4 lanes.

• Need for extra capacity but no opportunity to increase the footprint of the plant

• The solution was to convert the AS into an MBBR (more compact):

• 4 lines of 2 reactors. Total volume of 4,720 m3 (2,360 m3 K5)

Performance: • MBBR guarantee < 10 mg/l of SBOD• Performance test: SBOD out < 4.8 mg/l

Roughing MBBR (BAS = MBBR + AS) - Kima Egypt

Kima 1 - EgyptRoughing MBBR prior to AS

MBBR ahead of the existing AS

Kima 1: existing AS, capacity 21 MLD 35 MLD

Kima 1 Parameters

Units Inlet Outlet

Average flow m3/d 30 000

BOD mg/l 500 12

COD mg/l 1000 60

TSS mg/l 400 15

1) Remove a fraction of soluble COD (50%) upstream the AS

2) Improve the effluent TSS since direct discharge to the Nile

Increased COD load Increased Sludge Production Decreased SRT on AS

Two needs

Cudworth WwTW, polishing MBBR + DF

Cudworth WwTWPolishing after trickling filters

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2 Primary settlers + 3 Trickling filters + 2 Humus tanks

Need for an increased secondary capacity (design horizon 2025)

Influent Characteristics to MBBR (outlet trickling filters)

Parameter Units Value

Average flow m3/d 2946

FFT m3/d 5440

BOD5 loadkg/d 74

mg/l 25

NH4-N loadkg/d 44

mg/l 15

TSS loadkg/d 118

mg/l 40

• Design horizon for 2025 population equivalent of 10,693• Need for increased secondary capacity• Need for improved nitrification capacity, BOD and solids

removal

Discharge Standard

Parameter Unit Value

Total BOD5 as 95%ile mg/l 10

NH4-N as 95%ile mg/l 3

TSS as 95%ile mg/l 15


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Several options considered: • Gravity flow activated sludge + discfilters• Pumped flow activated sludge + discfilters• Additional trickling filter/humus tank + MBBR + discfilters

• 2 stages because low NH4-N (< 3 mg/l)• 1st stage operates at higher residual NH4-N and higher nitrification rates


NH4-N Units 2013 2014 2015 2016 4Yr

Design 95%ile mg/l 3 3 3 3 3

Actual 95%ile mg/l 0.78 0.49 0.77 0.76 0.71

Average mg/l 0.25 0.20 0.24 0.18 0.22

Max mg/l 2.4 1.36 2.0 1.5 2.4

Veolia biofilm based solutions

• Keep the sludge recirculation of the AS• Media only in a fraction of the AS

HYBAS or IFAS (MBBR in AS)

• Fast growing bacteria (heterotrophs, aerobic & denitrifiers) grow in MLSS

• Slow growing bacteria (nitrifiers) grow in the biofilm on the media since not enough SRT in MLSS

• Upgrading carbon removal AS to nitrification or total nitrogen removal without any tank expansion

• Adding carriers for nitrification in a fraction of the existing AS reactor

HYBAS APPLICATION

Marquette-les-Lille WwTW, France

Challenges: o Increasing populationo Strict nitrogen demandso Relatively limited space available

Lille WwTW Upgrade of an AS plant into Europe’s largest HYBAS

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HYBAS!• More compact than AS (55,000 m3) Fit in the available volume

• Lower sludge age higher biogas efficiency in anaerobic digestion • Biological P removal as in AS• Less carriers than pure MBBR (7,600 m3 of Chip M)

• Only nitrification on carriers• Chemical free TSS separation unlike pure MBBR and Biostyr• Robust facing peak loads and toxicity

• Nitrifiers in the biofilm more protected than in floc

Processes evaluated: • AS: Too large• SBR: Preference for continuous operation• Pure MBBR: most compact but higher CAPEX (carriers for COD removal, nitrification, denitrification)

• Membranes: high CAPEX and complex operation• Biostyr: high chemical consumption for TSS separation

Lille WwTWUpgrade of an AS plant into Europe’s largest HYBAS

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PreAnoxDenitr. NO3-N RAS

AnaeroPromote Biolog P removal

PreDNDenitr NO3-N REC

HybasChipM carriers nitrification

PostNitNH4-N Polishing AS

PostDNNO3-N Polishing AS

ReOx• Remove remaining COD• Strip N2 (g) bubbles• Chemical P co-precipitation

Secondary clarifiers

TertiaryHydrotech filters

FeCl3 Methanol

3 identical trains:

Lille WwTW Upgrade of an AS plant into Europe’s largest HYBAS

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Design Parameters

Design data - Inlet to the Hybas™ (after Multiflo and with reject water)

Unit

Average flow 246,342 m3/d

BOD5 91 mg/L

COD 231 mg/L

TSS 114 mg/L

TKN 35 mg/L

TP 5 mg/L

Parameter ConcentrationBOD5 20 mg/lCOD 90 mg/lTSS 30 mg/lTKN 5 mg/lTN 10 mg/lTP 1.0 mg/l

Parameter ConcentrationBOD5 6 mg/lCOD 70 mg/lTSS 10 mg/lTKN 2 mg/lTN 10 mg/lTP 0.7 mg/l

Objectives in 2027:

Moyenne Flow outlet WWTP

Average conc outlet of the biological treatment (mg/l)

MonthMonthly averages

TSS BOD5 COD TKN N-NH4 N-NO2 N-NO3 TN Pt

JANVIER 160,511 2.2 3.1 19.6 4.4 1.7 0.2 4.8 9.4 0.9FERVRIER 162,925 2.4 3.0 23.4 4.4 2.0 0.2 5.4 10.0 0.8

MARS 148,024 2.5 3.1 20.6 4.3 2.3 0.2 4.8 9.2 0.5AVRIL 144,292 2.5 3.3 26.5 4.1 2.7 0.1 4.4 8.7 0.5MAI 120,768 2.4 3.0 26.6 3.3 1.7 0.1 4.2 7.6 1.0JUIN 108,019 2.7 3.1 25.9 3.3 1.8 0.1 3.5 7.0 0.7

JUILLET 97,098 3.4 3.1 26.8 3.5 1.7 0.1 3.8 7.4 1.1AOUT 101,571 2.1 3.0 23.1 2.1 1.0 0.1 4.9 7.1 1.4

SEPTEMBRE 116,356 1.9 3.2 19.2 2.5 1.3 0.2 5.6 8.2 0.8OCTOBRE 106,914 2.5 3.1 28.2 3.6 2.1 0.2 4.7 8.5 0.5

NOVEMBRE 141,024 2.6 3.0 22.7 3.5 2.2 0.2 5.0 8.6 0.6DECEMBRE 133,302 2.6 3.0 19.3 2.5 1.5 0.1 5.7 8.2 0.5

AVERAGE 2 3 23 3 2 0 5 8 1

Objectives today:

Results year 2012:

Already reaching 2027 limits

Reaching current limits and almost there with 2027 limits• Higher DO in HYBAS to lower the NH4-N• Boost P chemical co-precipitation

Conventional Nitrification- Denitrification vs Anammox

O2

NO3-

AOB

COD

Heterotrops

NH4+

NO2-

NOB

55%

45%

N2 + NO3-

Anammox

NH4+

NO2-

89% 11%

O2

(40%)

AnoxicAerobic

COD

(0%)

-60% O2 -100% COD

Big Savings ££££

Properties of Anammox bacteria & AOB/NOBs

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- Grow in anoxic conditions (oxygen-free)- Very slow growing bacteria (slower than nitrifiers) Need very high SRT

- High temperature ideal- Biofilm on the carriers optimum No washout- Biofarm concept to accelerate the start up 10% of the carriers are already

seeded with Anammox Reduce start up from 18 months down to 2-3 months

❑ Reject water from anaerobic digestion :• Low COD/TKN ratio• High Temperature

❑ Research going on for mainstream water• Soon full scale demonstration

Five Fords WwTW, ANITA Mox

Five Fords WwTWFlexible & robust liquor treatment

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Five Fords WwTP (Wales), 170 000 PE

- Able to remove up to 85% of ammonia- Robust (THP generates toxics- Compact (optimised CAPEX)- Competitive OPEX

Problem:• Increase amount of the sludge to treat within the anaerobic digestion• Implementation of Thermal Hydrolysis within the anaerobic digestion

• Higher nitrogen release (2,000 mg/L TKN)

N out from the sludge treatment unit 25% of the N in the mainstream plant

Need to treat this in a sidestream process

Requirements from the client

Five Fords WwTWFlexible & robust liquor treatment

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Reactor volume: 927 m3Media volume: 410 m3 of K5

SOLUTION: HYBAS ANITAMOX

Current status:• Civil construction done• Commissioning – start-up Q1 2019

Considerations to take for THP water:• Dilution water needed Dilute the high N and toxic organic compound concentrations

• 1.4 treated effluent / 1 THP reject water• Buffer tank upstream the HYBAS Anitamox Sludge centrifuges do not operate 24/7

Q & A

Bruno Bigot – Chief Technical Officer, Northern Europe

07775 561 [email protected]

William Jeal – Sales Manager

07825 088 [email protected]

mailto:[email protected]

mailto:[email protected]

key sectors served - ciwem...kima 1 - egypt roughing mbbr prior to as mbbr ahead of the existing as...

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