concrete in biological treatment plants needs...

PDA Europe 2010 Annual Conference – It’s Time to… Polyurea – Sitges, 15-17 November

Concrete in Biological Treatment Plants needs

Protection

Dr Ylva Edwards


Outline

WR project 27 (2009/2010)• Method• Results• Conclusions and recommendations

WR project 34 (2010)• Different products• Comparison• Suggested test program


Biological treatment plants in Europe

www.compostnetwork.info

http://www.compostnetwork.inf


Examples of concrete damage

FLOORin reception hall for food waste

RECEPTION TANKin biogas plant


Methodology (WR 27)

• Survey (some 20 plants)

• Chemical analysis(10 plants)

• Analysis of concrete and reinforcement(3 plants)


Biological treatment plants

Leachate, food waste:

• pH 4, acetic acid…..• Phosphates• Chlorides• …….• 70°C


Result: analysis of concrete and reinforcement MICROSCOPY

ATLEVERKEN

8,7x6,4 mm


Result: analysis of concrete and reinforcement

BORLÄNGE


Result: analysis of concrete and reinforcementMICROSCOPY – SEM/EDS

Calcium Phosphorus

Leached zone: Calcium phosphate


Actions made / tested for preventing concrete damage and reinforcement corrosion

• Plastic lining paint• MMA technology based

surface coating products• Protection with stainless

steel• Epoxy treatment• Mastic asphalt (PGJA)


Conclusions and Recommendations, WR 27

• Concrete does not have sufficient resistance to food waste.

• Surface protection is needed.• New metods are required for testing surface protection

products in their ”proper” environment.

WR 34

• New Requirements specifications for surface protection of concrete in biologica treatment plants!


Chemical resistanceMethod ?

EN 1504-2 / EN 13529

Tes ng liqui d in Annex:

•Organic acids: ace c aci d and propionic acid 50/50

Class III (the best):

•28 days with pressure

•Hardness before and a er •≥ 50%

Test apparatus


Abrasion resistance / wear

ASTM 4060• Load 500 g, 1000 g

• Wheel C-10, C-17, H 22…

• Cycles 500, 1000

Taber Abraser

Type of surface protection to be tested Wheel type

All types of surface, general handling CS 10

Flooring with pedestriantraffic CS 17

Flooring with vehicular traffic H 22


Abrasion resistance / wear

EN 1504-2

• ISO 5470-1 (Taber test)• H22

• 1000 cycles

• 1000 gram

• < 3000 mgOR

• EN 13813 (Floor screeds)

• eg EN 13892-5 (steel wheeland load 2000 N)

Taber Abraser


Comparing different products......

Test results are difficul t to compa r e,

such as:

• Chemical resistance: Reported resistant, but…?

• Abrasion: Taber, but parameters…?


Proposal for Testing program

• Membrane (free films)• Functional testing on the system

• Suitable parts depending on type of coating and environment!

• Based on similar for bridges, (Swedish TRA, EOTA/ETAG, EN, ISO..)

• Waterproofing membranes / systems, protection and repair of concrete structures/ Floor screeds……


Proposal for Testing programChemical resistance

• Special testing liquid: 2 % acetic acid, pH just below 4, + 0,5% chlorides + 0,2% phosphate…..

• Storage temperature: 23°C, 40°C, 70°C

• Time: 28 d? (EN 1504-2, EN 13529)

Properties to compare?

• Tensile strength• Tensile bond,• Concrete analysis


Proposal for Testing programAbrasion resistance

•ISO 5470-1 (ASTM 4060 Taber test)

•For floor s: wh eel type H-22 or according to EN 13892

•Room temperature


2011Laboratory

Yet to be evaluated:• Chemical resistance• Abrasion resistance

Field

Test sites and follow-up in the field

concrete in biological treatment plants needs...

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