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27/11/2014 ARBI 1

Automated Reed Bed Installations

Dr Rob Morris

Nottingham Trent University

Speaker notes – slide 1

• In summary, this project, through the consortium, incorporates the Design, Construction, and testing of an Autonomous Reed Bed Installation.

• Reed Beds or Constructed Wetlands are used widely across Europe, and indeed globally, as a sustainable , low maintenance, low carbon technology for the treatment of municipal (sewage) and industrial waste waters.

• ARBI offers significant, novel advantages over existing constructed wetland water treatment systems, and thus will encourage the uptake of this water treatment technology. -

• This not only will enhances the protection of the environment and create an environment but should also increase revenue and employment within the industry.

• The consortium consists of seven members, 5 SMEs and 2 RTDs (Research Organisations)

• ARM Ltd (SME) Based near Birmingham UK

– Specialist designer and constructor of reed bed treatment systems, over 450 to date

– Providing Coordination of the project..

• LAB TOOLS Ltd (SME) Based near Canterbury, UK.

– rep Dr Beau Webber

– specialise in nano science/ nano technology instrumentation design

– will be providing the electronic control systems for the probe and associated software.

• LIGHTMAIN LTD (SME) Based in Rotherham UK

– rep Phil Borrington

– Specialise in the design and construction of housings for use in harsh conditions.

– will be developing and constructing the housing for the system to contain the complete ARBI system.

• OxyGuard (SME) Based Birkeroed, Denmark

– Specialise in Water Quality Measuring and monitoring equipment

– Will be designing and supplying appropriate water quality sensors

• TECHNOSAM Ltd (SME) Based Satu Mare, Romania

– Rep by Markos Tiberiu

– Specialise in industrial automation control systems

– Will be designing and supplying the autonomous control system for environmental conditioning.

• NOTTINGHAM TRENT UNIVERSITY (RTD) Based in Nottingham, UK

– Rep Dr Robert Morris

– Specialise in globally recognised research in NMR technology and associated electronics.

– Will be designing and testing the MR clogging probes and electronics

• UNIVERSITAT POLITECNICA CATALUNYA (RTD) Based in Barcelona, Spain

– Rep Prof Joan Garcia,

– World leaders in interdisciplinary research into Eco- Innovative Treatment Systems

– Developing and testing environmental control systems including aeration, heating and step feeding.

27/11/2014 2 ARBI

Traditional Constructed Wetland

27/11/2014 ARBI 3

Waste Water In

Water Loving Plants

Gravel Bed with Plastic Liner Clean Water Out

Speaker notes – slides 3 and 5

• Slide 3 - Traditional Constructed Wetland: Excavation lined - media, reeds

• - Biological systems – but use physical and chemical removal mechanisms also

• - different media, reeds, = different mechanisms of action.

• No moving parts = simple and robust = Low maintenance.

• Can be operated by gravity alone so low/no power requirement

• can be designed to remove a specific level of contaminant from a waste water to achieve regulator specified consents

• Environmentally friendly, They create an environment as well as protect the environment

• Where used they increase local biodiversity

• Can be land intensive

• Slide 5 – The Problems – ARBI will address

• FIRST ISSUE - Clogging

• As they degrade contaminants they generate biomass – Bugs/reed matter

• Inevitably an excess is generated and this fills the interstitial spaces within the media, reducing hydraulic conductivity = clogging

• Clogging leads to short circuiting, over surface, through channels.

• Leads to requirement for refurbishment. ( 7-8 years)

• Problem – is that we can’t determine how clogged a bed is just by looking at it.

• Can’t budget or plan for it easily.

• Second Issue – Environmental impacts

• is that reed beds can be subject to the vagaries of the climate - many mechanisms are temperature sensitive

• They rely on passive diffusion of Oxygen into the bed to fuel microbial activity – Oxygen usually limiting.

• ARBI’s proposed solution is to develop an instrument to measure/monitor clogging and develop modular, transportable reedbeds that can be exchanged with minimal disruption and refurbished off-site.

27/11/2014 4 ARBI

The Problem

27/11/2014 ARBI 5

5 10 15 20

The Solution

27/11/2014 6 ARBI

Clo

ggin

g In

dex

, a.u

.

USP

Years

Standard CW

Refurbishment Required

ARBI

Module Replacement

Another Problem!

27/11/2014 7 ARBI

Clean Gravel

Old Method

27/11/2014 ARBI 8

Speaker notes – slides 8, 10, 12 and 14 Slide 8 Existing methods for clogging detection.

• Visual

• Prerformance

• Tracer dye experiments

• HC measurements but this is complex, long winded and laborious, only provides a snapshot.

Slide 10 New method, developed in WP1 – MR Sensor (magnetic resonance sensor) cost £20-30

Slide 11 T1 is the ‘relaxation’ of the curve http://en.wikipedia.org/wiki/Relaxation_%28NMR%29 i.e. how the signal changes with time

Slide 14 ARBI is a modular reed bed treatment system incorporating

• Clogging sensor

• Aeration system

• Heating system and

• Feedback control hardware and software

• Thus providing clogging monitoring and optimised performance

• This extends operational periods between refurbishments

• It can be installed with little or no wetland knowledge

• The units come with reeds pre-grown and hence represent no down time for the customer

• The life of the module will be extended over a traditional wetland in that optimised conditions are provided for treatment

• Continuous monitoring of the module allows unattended operation

• The ARBI module has a smaller footprint than a traditional wetland and can be utilised economically for lower volumes of influent or in industrial settings with limited ground space

27/11/2014 9 ARBI

New Method

27/11/2014 ARBI 10

MR Probes

27/11/2014 ARBI 11

MRI NMR

RELAXATION

0 0.2 0.4 0.6 0.8 2.5

3

3.5

4

4.5

5

5.5 x 10 5 A1_200_a

T R in s

NM

R s

ign

al

MR Probes

27/11/2014 ARBI 12

27 November 2014

Field Testing

ARBI

What Does ARBI Do?

27/11/2014 ARBI 14

EU Project

27/11/2014 15 ARBI

http://upload.wikimedia.org/wikipedia/commons/d/d1/Fireplace_Burning.jpg http://abovethecrowd.com/2014/01/24/on-bubbles/ http://www.artstore.co.uk/blundell-harling-challenge-ferndown-drawing-board-a2-c-207-p-11673

http://aircraftdeicing.blogspot.co.uk/ http://liquidassets.psu.edu/outreach/pressroom/photos/BostonSewer.jpg

Prototype ARBI Module

27/11/2014 16 ARBI

Test Beds

27/11/2014 ARBI - 606326 17

Results

27/11/2014 18 ARBI

T1 sensitivity

27 November 2014 19

Temperature Dependence

27/11/2014 20 ARBI

-10 0 10 20 30 Temperature oC

80

70

60

50

40

30

20

10

T 2ef

f (m

s)

Aeration System

Flow rate of 720 l/h from 12W air pump.

21

• Controlled set

points: 5, 3, 1.5,

0.5, 0.2 ppm

ARBI

Speaker notes – slides 21, and 23-29 Slide 21 Aeration and heating experiments were run separately , Aeration first.

Slides 23 to 26 measure the effect of aeration on COD reduction and on ammonium oxidation (nitrification).

• As small amount of aeration had a large increase in COD reduction

• Nitrification required more aeration.

Slides 27 and 28

• With the control at 10-15C, the effect of heating to 20-25C was not statistically significant.

Slide 29 I’ve outlined before the issues/problems linked to the technology

• the passive diffusion of oxygen into the effluent and bed

• Varying climatic conditions – these can effect temperature sensitive removal mechanisms.

• unpredictable/unobservable clogging rates resulting in ineffective use of the bed.

• This variability in performance and high land take can put clients off or make constructed wetland solution impractical.

• However:

• The benefits that the ARBI system offers to clients over existing constructed wetland treatment systems are:

• 1. Proactive, accurate monitoring of the clogging process, allowing clients to budget ahead for any required refurbishment

• 2. Determination of the optimum time and level of refurbishment (to suit budget)

• 3. Increased and more consistent performance of constructed wetlands through environmental conditioning reducing reed bed size and thus capital costs

• Clients will see BETTER PERFORMANCE, IMPROVED CONSISTENCY, LOWER COSTS, MORE CONTROL across all applications SEWAGE, INDUSTRIAL and SUDS

27/11/2014 22 ARBI

Aeration System

56% 46% 40% 35% 3%

23

COD concentration

ARBI

5 3 1.5 0.5 0.2

O2 Concentration (mg/l)

CO

D C

on

cen

trat

ion

(m

g/l

)

600

500

400

300

200

100

0

3

1.5

0.5

0.2

Aeration System

24

0 1 2 3 4 50

10

20

30

40

50

60

O2 Set Point, mg/l

CO

D C

on

cen

trati

on

, m

g/l

ARBI

Ch

ange

in C

OD

Co

nce

ntr

atio

n (

%)

60

50

40

30

20

10

0 0 1 2 3 4 5

O2 Concentration (mg/l)

Aeration System

69% 45% 28% 18% 2%

25

NH4+-N concentration

ARBI

5 3 1.5 0.5 0.2

O2 Concentration (mg/l)

NH

4+

Co

nce

ntr

atio

n (

mg

/l)

40

35

30

25

20

15

10

5

0

Aeration System

26

0 1 2 3 4 50

10

20

30

40

50

60

70

O2 Set Point, mg/l

NH

4+ C

on

ce

ntr

ati

on

, m

g/l

ARBI

Ch

ange

in N

H4

+ C

on

cen

trat

ion

(%

) 70

60

50

40

30

20

10

0 0 1 2 3 4 5 O2 Concentration (mg/l)

Heating System

27

Temperature

ARBI

Heating System

28

COD concentration

Control more efficient

Heated more efficient

No statistically significant differences

ARBI

1 2 3 4 5 Week

CO

D C

on

cen

trat

ion

(m

g/l

)

600

500

400

300

200

100

0

What is the demand for this technology?

27/11/2014 ARBI 29

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http://shop.septictank.co.uk/image/data/Low-Profile-Septic-Tank-3800-Litre.png

Impact

27/11/2014 ARBI 30 http://blog.airdye.com/goodforbusiness/wp-content/uploads/2009/08/polluted-river.jpg

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Where Next

27/11/2014 31 ARBI

http://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Feedback_loop_with_descriptions.svg/500px-Feedback_loop_with_descriptions.svg.png

Conclusions

• ARBI represents an opportunity to offer wetlands to users who would not typically consider installation

• Development is progressing well, fully automated unit expected January 2015

• Aeration of great benefit, detection with MR a useful tool but heating is unnecessary unless temperature less than 6oC

27/11/2014 32 ARBI

Speaker notes – slides 30, and discussion Slide 30 Envionmental Impact

• The consistency of performance associated with the simplicity of a self monitoring modular structure makes it an easier decision for clients to buy and thus increasing the use of this sustainable water treatment technology.

• Important to note that not only do they Protect the Environment they Create an Environment / habitat increasing biodiversity in a location.

Discussion

• Thames Water found aerated reedbeds were more expensive than activated sludge process, though presumably there is some scale [size] effect. It has also found [wastewater treatment] reedbeds need to be refurbished after 7 years not 12.

• ARBI has found that “intelligent aeration” extends the life of a reedbed – a blast of air will shake the media

• Heating is of decreasing interest in the project except for special cold climate cases (niche)

• Building, installing and refurbishing the modules would create jobs but operation is automatic

• The standard module size is 2m x 1m x 1m which gives a 10t lift (skip truck) when full

• The units will be run for a complete season automatically to measure performance

• It was agreed by all that the sensors are useful

• The cost of the controller for the NM sensors has decreased from £40k to £3k and Rob Morris hopes it will reduce to £300

• The NM sensor differentiates water in the biofilms from free water.

27/11/2014 33 ARBI

Acknowledgments

• The research leading to these results has received funding from the European Union's Seventh Framework Programme managed by the REA – Research Executive Agency http://ec.europa.eu/research/rea (FP7/2007_2013) under project reference 606326.

27/11/2014 34 ARBI

Thank You For Your Attention

27/11/2014 35 ARBI

www.ARBI-EU.com

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