WATER TREATMENT OF WATER COOLED AIRCONDITIONING SYSTEMS

Gavin Richardson

Queensland State Manager

HydroChem

10 May, 2016 QLD Division technical meeting

Evaporative Cooling SystemsCooling Towers

Evaporative Cooling SystemsChillers

Evaporative Cooling Systems

Evaporative Cooling Water Systems

recycle and

conserve water

Evaporative Cooling SystemsCycles of Concentration

Evaporative Cooling SystemsCycles of Concentration

Evaporative Cooling SystemsActual Water Consumption

FlowRate

(Lt/Sec)

Heat Rejection

(kW)

Evaporation (Lt/Hr)

Bleed off @ 5

Cycles (Lt/Hr)

Bleed off @ 2.5 Cycles

(Lt/Hr)

Difference per 12 hour day

(Lt)

10 232 276 69 184 1,380

50 1,162 1,381 345 921 7,032

100 2,324 2,762 691 1,842 13,812

500 11,618 13,811 3,453 9,208 69,060

Temperature Drop – 5.6o CHeat Rejection Factor – 1.25Plant Load – 80%

Risks

Corrosion

Risks

Scale

Risks

Microbiological Growth

Risks

Biofilm

Legionnaires’ Disease

L.adelaidensis L.lyticum L.anisa L.londiniesnsis L.birminghamensis L.maceachernii L.bozemanii SG 1&2 L.micadei L.brunensis L.moravica L.cherrii L.nautarum L.cincinnatiensis L.oadridgensis L.dumoffii L.parisiensis L.erythra L.pneumophila SG 1-14 L.feeleii SG 1&2 L.quateriaensis L.fairfieldensis (b) L.quinlivanii SG 1&2 (a) L.geestiae L.rubrilucens L.gormanii L.sainthelensis SG 1&2 L.gratiana L.santicrucis L.hackeliae SG 1&2 L.shakespearei L.israelensis L.spiritensis L.jamestowniensis L.steigerwaltii L.jordanis L.tucsonensis L.lansingensis L.wadsworthii L.longbeachae SG 1&2 L.worsleiensisf L.londiniensis

Legionnaires’ Disease

L.pneumophila

0

20

40

60

80

100

0 10 20 30 40 50 60 70 80

Temperature oC

Gro

wth

Ra

te %

Legionnaires’Disease

Three necessary preconditions

1. Water with a sufficiently high population of pathogenic legionella bacteria

2. A means of transmission of this water into people’s lungs

3. Hosts with susceptibility to disease

Legionnaires’ Disease

Legal Responsibilities – Queensland Work Health and Safety Act (WHS Act), 2011

The WHS Act provides a framework to protect the health, safety and welfare of all workers at work and of all other people who might be affected by the work.

The WHS Act aims to protect the health and safety of workers and other people by:•eliminating or reducing workplace risks.•ensuring effective representation, consultation and cooperation to

address health and safety issues in the workplace.•encouraging unions and employers to take a constructive role in

improving health and safety practices.•promoting information, education and training on health and safety.•providing effective compliance and enforcement measures.•delivering continuous improvement and progressively higher standardsof health and safety.

Person conducting a business or undertaking (PCBU)

The WHS Act refers to PCBU’s as responsible parties in the application of the requirements of the act. A PCBU is a person conducting a business or undertaking alone or with others, whether or not for profit or gain. A PCBU can be a sole trader (for example a self employed person), a partnership, company, unincorporated association or government department of public authority (including a municipal council). An elected member of a municipal council acting in that capacity is not a PCBU.

The WHS Act requires all PCBUs to ensure the health and safety of workers, so far as is reasonably practicable. Workers include volunteers, contractors and contractors’ workers. PCBUs also have the same duty of care to any other people who may be at risk from work carried out by the business. A self-employed person must ensure his or her own health and safety

Legionnaires’ Disease

Australian/New Zealand Standard 3666

Air-handling and water systems of buildings – Microbial control

Part 1: Design, installation and commissioningEasy and safe access, made with materials which reduce dirt collection,

drift eliminators, automatic water treatment systems, located to discharge exhaust away from air intakes/occupied areas and away from kitchen

exhausts (8m), minimize direct sunlight

Part 2: Operation and maintenanceMonthly inspections and maintenance, minimum six monthly cleans, site

log books

Part 3: Performance-based maintenance of cooling water systemsAlternative to Part 2, assessment of risk factors, monthly microbiological

analyses for specific legionellae and heterotrophic colony count (HCC), monthly chemical tests, control strategies

Legionnaires’ Disease

Workplace Health and Safety Queensland

Amalgamation of the three Australian Standards and other State Guidelines

Critical Risk Factors – Stagnant Water, Nutrient Availability, Poor Water Quality, Deficiencies in the Cooling Tower, Location of the Cooling Tower

Risk Management Plan (RMP)

Service Contract to define the responsibilities of the water treatment service provider (WTSP) and set KPIs

Legionnaire’s DiseaseMicrobiological Testing

Reporting

Reporting

Legionnaire’s DiseaseControl Strategies

Legionnaire’s DiseaseControl Strategies

Management Tools

Corrosion Inhibitors

Management Tools

Anodic Protection

Management Tools

Cathodic Protection

Management Tools

Scale Inhibitors

Management Tools

Biocides

Management tools

Advances in Dosing Equipment TechnologyModbus Communication Platform direct with BMS

Remote Alarm Monitoring (Modem)

Reliable Sensors and Chemical Delivery Systems

Management Tools

Filtration

Management Tools

Building Automation

Potable/Warm Water Treatment

Health and Aged Care Facilities

Potable/Warm Water Treatment

Main Points

• Managers of facilities have a duty of care to develop a risk management plan that has detailed written procedures for controlling risk and monitoring programs.

• It is recommended a multidisciplinary team of suitably experienced and qualified people to develop a holistic, cohesive approach to managing risk.

• Prevention strategies should be implemented to reduce risk, rather than just testing for Legionella and taking remedial action to disinfect:

• Point of use filtration in critical care areas• Chlorination of incoming supply to maintain > 0.5 mg/lt free chlorine• Distal point monitoring to ensure > 0.2 mg/lt free chlorine• Documented flushing program to maintain chemical residuals in areas

of low use

Potable/Warm Water Treatment

Health Act Amendment

Presented by: Gavin Richardson State Manager - QLD

Office: (07) 3344 3266 Mobile: 0413 949 615 Australia wide: 1300 558 788Email: gavin.richardson@hydrochem.com.auWebsite: www.Hydrochem.com.au