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SCHEDULE A - Directorate of Commercial Taxes

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SCHEDULE A - Directorate of Commercial Taxes

WATER TRANSFORMED:

    SUSTAINABLE WATER SOLUTIONS FOR

    CLIMATE CHANGE ADAPTATION

    MODULE C: INTEGRATED WATER

    RESOURCE PLANNING AND MANAGEMENT

    This online textbook provides free access to a comprehensive education and training package that

    brings together the knowledge of how countries, specifically Australia, can adapt to climate change.

    This resource has been developed through support from the Federal Government’s Department of

    Climate Change’s Climate Change Adaptation Professional Skills program. ;

    CHAPTER 6: URBAN AND INDUSTRIAL WATER

    TREATMENT, REUSE AND RECYCLING.

LECTURE 6.2: INDUSTRIAL WATER REUSE, TREATMENT AND

     RECYCLING TECHNOLOGIES.

? The Natural Edge Project (‘TNEP’), 2010

    Copyright of this material (Work) is owned by the members of The Natural Edge Project, based at Griffith University and the Australian National University.

    The material contained in this document is released under a Creative Commons Attribution 3.0 License. According to the License, this document may be copied, distributed, transmitted and adapted by others, providing the work is properly attributed as: ‘Smith, M., (2010) Water Transformed: Sustainable Water Solutions for Climate Change

    Adaptation, Australian National University, Griffith University, The Natural Edge Project (TNEP), Australia.’

    http://www.naturaledgeproject.net/Sustainable_Water_Solutions_Portfolio.aspx. Document is available electronically at

    Acknowledgements

    The Work was produced by The Natural Edge Project supported by funding from the Australian Government Department of Climate Change under its Climate Change Adaptation Skills for Professionals Program’. The

    development of this publication has been supported by the contribution of non-salary on-costs and administrative support by the Griffith University Urban Research Program, under the supervision of Professor Brendan Gleeson, and the Australian National University Fenner School of Environment and Society and Engineering Department, under the supervision of Professor Stephen Dovers.

    Chief Investigator and Project Manager: Mr Karlson ‘Charlie’ Hargroves, Research Fellow, Griffith University.

    Principle Researcher: Dr Michael Smith, Research Fellow, ANU Fenner School of Environment and Society.

Peer Review

    The peer reviewers for this lecture were Professor Stephen Dovers - Director, Fenner School of Environment and

    Society, Australia National University. Anntonette Joseph, Director Water Efficiency Opportunities, Commonwealth

    Department of Environment, Water, Heritage and the Arts. Harriet Adams - Water Efficiency Opportunities,

    Commonwealth Department of Environment, Water, Heritage and the Arts.

    Review for this module was also received from: Chris Davis, Institute of Sustainable Futures, University of Technology;

    Alex Fearnside, Sustainability Team Leader, City of Melbourne. Associate Professor Margaret Greenway, Griffith

    University; Fiona Henderson, CSIRO Land and Water, Dr Matthew Inman, Urban Systems Program, CSIRO

    Sustainable Ecosystems, CSIRO; Dr Declan Page, CSIRO Bevan Smith, Senior Project Officer (WaterWise) Recycled

    Water and Demand Management, Queensland Government, Department of Natural Resources and Water. Dr Gurudeo Anand Tularam, Griffith University. Associate Professor Adrian Werner, Associate Professor of Hydrogeology, Flinders

    University, Professor Stuart White, Institute of Sustainable Futures, UTS,

    Disclaimer

    While reasonable efforts have been made to ensure that the contents of this publication are factually correct, the parties involved in the development of this document do not accept responsibility for the accuracy or completeness of the contents. Information, recommendations and opinions expressed herein are not intended to address the specific circumstances of any particular individual or entity and should not be relied upon for personal, legal, financial or other decisions. The user must make its own assessment of the suitability of the information or material contained herein for its use. To the extent permitted by law, the parties involved in the development of this document exclude all liability to any other party for expenses, losses, damages and costs (whether losses were foreseen, foreseeable, known or otherwise) arising directly or indirectly from using this document.

    This document is produced for general information only and does not represent a statement of the policy of the Commonwealth of Australia. The Commonwealth of Australia and all persons acting for the Commonwealth preparing this report accept no liability for the accuracy of or inferences from the material contained in this publication, or for any action as a result of any person’s or group’s interpretations, deductions, conclusions or actions in relying on this material.

    Enquires should be directed to:

    Dr Michael Smith, Research Fellow, Australian National University, Fenner School of Environment and Society, Co-Founder and Research Director 2002-2009, The Natural Edge Project. Contact Details at

    http://fennerschool.anu.edu.au/people/academics/smithmh.php

    Prepared by The Natural Edge Project 2009 Page 2 of 17 Water Transformed: Sustainable Water Solutions

    Urban and Industrial Water Treatment, Reuse and

    Recycling to Adapt to Climate Change.

Lecture 6.2: Industrial Water Reuse and Recycling

    Wastewater Treatment and Recycling Technologies.

    Educational Aim

    This lecture firstly overviews a number of companies that have achieved at least 50 per cent potable water savings through an integrated approach to water efficiency, water treatment and reuse. In lectures 2.1-2.4, 3.1-3.3 and 4.1-4.3 we showed that there was a strong business case for using water more efficiently. Here we provide examples which show that there is also a business case for treating and reusing water onsite to further reduce freshwater and trade waste costs. To help business’s identify opportunities in this area, the main purpose of this lecture is to provide an overview of the different water treatment technologies. As earlier lectures have shown, there is significant potential to increase the level of water reuse and recycling in Australia. But to achieve this, greater understanding and awareness is needed across business and industry. This lecture, and its further reading resources, seek to provide such a guide.

    Key Learning Points

    1. There are now many examples of business using combinations of wastewater treatment technologies to enable significant quantities of water to be recycled and reused. When this is combined with water efficiency measures, businesses can significantly reduce their reliance on potable freshwater. For instance, Inghams Enterprises have reduced mains water usage by 70%

    1achieving savings of 545 megalitres per annum. Inghams Enterprises have achieved these

    remarkable results by installing an Advanced Water Treatment Plant which uses a combination of physical, biological and chemical processes to treat the water, including biological nutrient

    2removal, membrane separation techniques, ultraviolet radiation and chlorination. These

    processes provide a multi-barrier approach which has enabled Inghams Enterprises to comply

    3with Australian water recycling and drinking water guidelines.

    2. Achieving the desired level of water quality from wastewater will generally require multiple stages of treatment as in the Ingham Enterprises case. The efficiency and effectiveness of the chosen method can be improved by choosing an appropriate pre-treatment. Regular system maintenance is essential for maintaining consistent water quality. Another key consideration that

     1 DEWHA (2010) Prime Minister’s Water Award Factsheet. DEWHA Water Efficiency Opportunities Program at http://www.environment.gov.au/water/publications/urban/pubs/pm-waterwise-award-winners.pdf Accessed 26 May 2010. 2 Ibid. 3 DEWHA (2010) Prime Minister’s Water Award Finalists – Inghams Enterprises. DEWHA Water Efficiency Opportunities Program at http://www.environment.gov.au/water/publications/urban/pubs/pm-waterwise-award-finalists.pdf accessed May 20 2010 National Health and Medical Research Council (2004) Australian Drinking Water Guidelines. Commonwealth Government. http://www.nhmrc.gov.au/publications/synopses/eh19syn.htm Accessed 21 April 2010. Natural Resource Management Ministerial Council (NRMMC), Environment Protection and Heritage Council (EPHC), Australian Health Ministers Conference (AHMC) (2006) National Guidelines for Water Recycling: Managing Health and Environmental Risks. NRMMC, EPHC, AHMC. http://www.ephc.gov.au/taxonomy/term/39 accessed March 3 2010.

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    will determine the impact a system’s cost and complexity is how to manage the waste that will be

    4produced.

    3. The treatment method chosen for a system must deliver water quality appropriate for the end uses. The requirements of each location and end use application, together with the water and wastewater characteristics, will have specific design needs.

    4. There are broadly three main methods of wastewater treatment physical, biological and

    chemical. Within these 3 areas there are 6 different types of water or wastewater treatment technologies and approaches commonly used; flotation and basic filtration (physical), membrane filtration (physical), membrane bioreactor (physical and biological), biological treatment (biological),

    5ion exchange (chemical) and disinfection (chemical).

    5. Flotation and basic filtration: Flotation is an effective means of removing grease and oil, together with some suspended solids, from wastewater. Larger solids can be removed using basic filtration. These can be applied either as a pre-treatment, improving the efficiency of subsequent treatment processes, or to meet waste standards prior to discharge into sewers. 6. Membrane filtration: this involves forcing pressurised water or wastewater through a semi-permeable membrane. It is an effective means of removing solids and dissolved salts. Membrane technology has made some major advances in recent years and now has broad application. Membranes are available in four main types: microfiltration (MF), ultrafiltration (UF), reverse

    6osmosis (RO) and nanofiltration (NF). The latter two are particularly effective at removing salts, dissolved solids, enhanced organics and pathogen.

    7. Membrane bioreactors (MBRs): these are a proven option in the treatment of wastewater

    that use a single tank combination of an activated sludge process and either micro or ultra-filtration. A key advantage of this technology is the ease of upgrade or retro-fit to existing older

    7treatment plants. MBRs have application for both domestic wastewater and municipal and industrial waste treatment. When applied to the former, MBR output is of sufficient quality to be released to surface, brackish or coastal waterways or used in urban irrigation. Applied to the latter, membrane suspension combined with a suspended-growth bioreactor is effective. 8. Biological treatment: The biological treatment processes use micro-organisms to treat the waste water using similar process that occurs naturally but under more controlled conditions. There are three types of biological treatment approaches, anaerobic (for instance upflow anaerobic sludge bed reactors, suspended growth reactors, fixed film reactors), aerobic (for instance activated sludge process, sequential batch reactor, fixed film reactors) and mixed aerobic/anaerobic systems (for instance constructed wetlands).

    - Anaerobic: Anaerobic biological treatment usually involves anaerobic digestion which

    breaks down the biodegradable component of the waste to produce biogas and soil

    improver. The biogas can be used to generate electricity and heat and thus reduce

    greenhouse gas emissions.

     4 UN ESCWA (2003) Waste-Water Treatment Technologies A General Review. UN ESCWA. http://www.escwa.un.org/information/publications/edit/upload/sdpd-03-6.pdf Accessed 10 May 2010. 5 Ibid 6 Sydney Water (2009) Water Treatment Options. Sydney Water. Available at http://www.sydneywater.com.au/Publications/FactSheets/WaterTreatmentOptions.pdf Accessed 15 May 2010 7 Judd, S. (2006) Principles and Applications of Membrane Bioreactors in Water and Wastewater Treatment, Elsevier, Oxford. UK.

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    - Aerobic Treatment: In aerobic systems air is pumped through the wastewater in biological

    reactors. Aerobic biological systems are mostly used for treating low concentration waste

    (typically where the BOD is less than 1000mg/L). In these systems, about 50% of

    biodegradable organic matter is converted to sludge, which must be disposed of. The rest

    is converted to water and air. Aerobic systems are used in the food manufacturing industry

    and to treat municipal wastewater.

    - Combined Anaerobic/Aerobic Treatment Systems: Another important biological treatment

    approach is the use of constructed wetlands. Wetlands achieve biological treatment

    8through both natural anaerobic and aerobic processes. Constructed wetlands will be

    covered further in the following lectures on stormwater management, harvesting and reuse

    (lecture 6.3) and urban water sensitive design (Lecture 7.1). Finally, some biological

    treatment systems incorporate both anaerobic digestion and the aerobic process of

    composting. This can take the form of a full anaerobic digestion phase, followed by the

    maturation (composting) of the digestate.

    9. Ion exchange: widely applied in the treatment of water for refined end-uses, including the semi-conductor and pharmaceutical industries (which require ultra-pure water), and boiler-feed water. It is used to remove trace contaminants.

    10. Disinfection: this includes processes such as chlorination, and the use of ozone and ultra violet light, and is effective at killing pathogens such as viruses, bacteria and protozoa. It is usually applied as a secondary treatment in situations where there is a risk that treated water will come into contact with the human population.

    These water treatment technologies used in combination can help industry comply with the

    9Australian guidelines for recycling of water.

Brief Background Reading

    In lectures 2.1-2.4, 3.1-3.3 and 4.1-4.3 we showed that there was a strong business case for using water more efficiently. Here we provide examples showing that there is also great potential for businesses to treat and reuse water to further reduce their freshwater and trade waste costs. Ingham Enterprises is not the only company showing the potential for business from investing in water treatment/reuse and stormwater harvest and reuse opportunities. When companies invest in water efficiency opportunities in combination with water treatment and reuse opportunities the potable water savings can be significant.

    - At Port Kembla, on the NSW coast, Sydney Water’s largest industrial water recycling

    development generates a saving of approximately 17% of Wollongong’s daily water use.

    20 Ml of recycled water per day and used by the Port Kembla Coal Terminal and

    BlueScope Steel. The wastewater undergoes a multi-stage treatment to get it to tertiary

    level, after which microfiltration and reverse osmosis are applied to deliver water

    appropriate to BlueScope’s particular requirements. Any residual water undergoes

     8 Greenway, M. (2003) The role of wetlands in effluent treatment and reuse schemes. CD-ROM, Water Recycling Australia, 2nd National Conference 1-3 September, 2003 Brisbane. Australian Water Association, Sydney 9 Natural Resource Management Ministerial Council (NRMMC), Environment Protection and Heritage Council (EPHC), Australian Health Ministers Conference (AHMC) (2006) National Guidelines for Water Recycling: Managing Health and Environmental Risks. NRMMC, EPHC, AHMC. http://www.ephc.gov.au/taxonomy/term/39 accessed March 3 2010

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    additional treatment (ultraviolet light disinfection) before being discharged offshore via an

    10outfall.

    - At their Cartonboard Mill in Petrie, Amcor Australia has achieved an annual freshwater

    saving of more than 1000 Ml. Formerly in the top 10 water users in the area, this saving of

    over 4 Ml per day, has been achieved via a 90% reduction in the use of drinking water in

    11the manufacturing process, which now uses treated and purified recycled water instead.

    - With 55 projects focussing on saving water, Coca Cola Amatil is amongst the most efficient

    Coke bottlers internationally. The projects range across water treatment, recycling and

    reuse and stormwater harvesting, and have positioned the company at the forefront of

    12such efforts within the global beverage industry.

    - Diageo Australia Limited, an international beverage manufacturer, has achieved a 43%

    water saving at its Huntingwood site. This annual saving of 55.5 Ml has been realised

    through a combination of improved management practices and innovative water saving

    measures. Efficiency initiatives have enabled significant freshwater savings, but more than

    50% of the savings have been achieved through optimisation of the reverse osmosis

    13recovery process.

    - The Rossdale Golf Club has achieved an annual reduction of mains water usage of 35 Ml.

    This cut, a reduction of 56%, has been achieved through a combination of stormwater

    harvesting and construction of storage dams. The club has a 43 Ml storage capacity,

    comprised in part of an aquifer storage and recovery facility, and a permit to harvest

    14stormwater from a barrel drain adjacent to the property.

    In each of these examples these businesses have chosen specific water treatment technologies to enable their wastewaters to be treated to standards needed for that water to be reused. Water treatment is needed in many industries whether they reuse their wastewater or not as their wastewaters contain a significant number of pollutants that need to be treated before that water is re-released into natural systems. For instance in the following industries the following pollutants tend to be common

    - Iron production - Ammonia and cyanide, along with other chemicals, contaminate water

    used for cooling in the blast furnace production of iron. Water used in coke production

    (from coal), for separation of by-products, can contain contaminants including gasification

    products (e.g. naphthalene, benzene, cyanide, ammonia, phenols and cresols) as well as

    polycyclic aromatic hydrocarbons (PAH).

    - Steel production The hot and cold mechanical transformations involved in converting iron

    (or steel) into wire and other products, use water as a lubricant and coolant. The final stage

    of treatment (prior to use in manufacturing) involves pickling with strong mineral acid

    (usually hydrochloric and sulphuric). These two processes produce contaminants including

    hydraulic (soluble) oils, particulate solids, tallow, acidic rinse water and waste acid.

     10 Bluescope Steel (2006) Community, Safety and Environment Report Water Case Studies. Bluescope Steel at http://csereport2006.bluescopesteel.com/environment/water_case_studies.html#less accessed May 3 2010 11 Amcor (undated) Environmental Sustainability Water Use. Amcor at .http://www.amcor.com/about_us/sustainability_amcor/environmental_sustainability/64347357.html accessed May 3 2010 12 DEWHA (2010) Prime Minister’s Water Award Finalists. DEWHA Water Efficiency Opportunities Program at http://www.environment.gov.au/water/publications/urban/pubs/pm-waterwise-award-finalists.pdf accessed May 20 2010 13 Ibid. 14 Ibid.

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    - Mines and quarries - Slurries of rock particles are the main contaminants associated with

    quarries and mines, and result from the rock washing and grading process and rainfall

    run-off from haul roads and other associated exposed surfaces. Particulate haematite and

    surfactants contaminate wastewater from some separation operations (e.g. coal from

    native rock), while oils and hydraulic oils are commonplace. Metal mine and ore recovery

    operation wastewaters are contaminated with minerals found in the native rock, and can

    include undesirable materials left over after extraction of the desired materials. In the case

    of metal mines, these undesirable materials can include zinc and arsenic.

    - Food industry - Wastewater resulting from agricultural and food production tends to have

    high concentrations of suspended solids and has high biochemical oxygen demand (BOD).

    Variation in BOD and pH in fruit and vegetable and meat product effluent, as well as

    seasonal factors, make it difficult to predict the contaminants in food wastewater. Food

    processing wastes are generally high in organic material associated with cooking. These

    can include not only high levels of fats and oils, but also flavourings, salt, colours, acids

    and alkali. Wastewater from the slaughter and processing of animals contains strong

    organic contaminants (e.g. from blood and gut content), and can have considerable

    concentrations of growth hormones, antibiotics and pesticides. Wool processing produces

    wastewater hat contains significant levels of insecticides from residue from the fleeces. Clearly, industrial wastewaters need to be treated whether the water is going to be reused or released back into the environment. Sydney Water and many other water authorities have produced significant freely available information (see further reading) for commercial customers regarding treatment of trade waste (wastewater). Hence this lecture does not focus on this topic as it is well covered already. The rest of this lecture focuses on water treatment technologies which enable businesses to reuse and recycled water to reduce their dependence on mains water. To achieve this, water treatment is required to reduce the level of pollutants. Sydney Water has produced the following diagram that communicates both the main pollutants that need to be treated and which water treatment technologies can be used for such purposes. The rest of this lecture focuses on the main water treatment technological options as listed by Sydney Water here. (See figure 6.2.1)

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    Figure 6.2.1 Treatment options for water reuse.

    15(Source: Sydney Water, 2009)

    The following provides an overview of the main types of wastewater treatment technologies listed in the above Sydney Water diagram.

Flotation and Basic Filtration

    Flotation is an effective means of removing grease and oil, together with some suspended solids, from wastewater. Larger solids can be removed using basic filtration. These can be applied either as a pre-treatment, improving the efficiency of subsequent treatment processes, or to meet waste standards prior to discharge into sewers.

    16The most common flotation process is dissolved air flotation (DAF). Dissolved air flotation (DAF)

    is a water treatment process that clarifies wastewaters (or other waters) by the removal of suspended matter such as oil or solids. To do this, air is dissolved under pressure in the wastewater then released into a flotation tank at atmospheric pressure. Suspended matter adheres to the resulting air bubbles, floats to the surface, and is collected via skimming. Thus, DAF uses fine air bubbles to separate liquid particles and light suspended solids (but not

     15 Sydney Water (2009) Water Treatment Options. Sydney Water. Available at http://www.sydneywater.com.au/Publications/FactSheets/WaterTreatmentOptions.pdf Accessed 15 May 2010 16 Ibid.

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    dissolved contaminants) from wastewater. These particles and solids are floated to the surface via the bubbles, where they are skimmed from the surface in the form of sludge (4 6% solids). The

    efficiency of this process can be enhanced through the addition of flocculants and coagulants, which bind suspended particles into larger masses, though this may require some adjustment of the wastewater’s pH. It may necessary to use a balance tank so this process is not disturbed by the inflow of wastewater. With little operator input necessary, DAF is a relatively easy process that is cheap to run. One of the main applications of DAF is in the treatment of industrial wastewater effluent from industries including paper manufacturing, oil refining and natural gas processing and general water treatment. Its uses also include grease and oil removal from commercial kitchen wastewater and various applications in the paper and pulp industry.

Membrane Filtration

    Membrane filtration is a fast growing technology that can produce high quality effluent, in a wide range of situations. Membranes can provide consistent high quality water free of nearly all target

    17contaminants, regardless of influent quality. Membranes remove solids and dissolved salts from

    water and wastewater by forcing them through a semi-permeable membrane, generally under pressure. Concentrated waste is captured on the membrane surface. There are four major types of membranes:

    1. Microfiltration (MF) - MF removes contaminants by passing fluid (liquid or gas) through a membrane with pores of 0.1 to 10 microns. Pressure can be used but, unlike nanofiltration and reverse osmosis, is not essential. The membranes can be composed of fibers ranging from hollow and tubular, to track etched or spiral wound, and can be configured in either a submerged or pressure vessel arrangement. They are effective in filtering algae, large bacteria, sediment and particles, while allowing water, small colloids, dissolved organic matter, viruses and monovalent ions (Na+ & Cl-) to pass through.

    2. Ultrafiltration (UF) - UF employs hydrostatic pressure to force liquid onto a semipermeable membrane. The membrane allows water and solutes of low molecular weight to pass, while suspended solids and high molecular weight solutes are held back. An effective means of purifying and concentrating macromolecular solutions, UF is used to recycle flow and add value to later products in industries including food and beverage manufacturing, wastewater treatment, and chemical and pharmaceutical processing. By employing solution flow pressurisation, UF is widely applied in continuous systems for the purification, separation and concentration of target macromolecules. Targeting is effected by selecting a membrane with the appropriate molecular weight cut-off (MWCO).

    3. Reverse osmosis (RO) - RO involves the application of pressure to a fluid column in excess of its osmotic pressure. In a situation where two fluids containing differing concentrations of dissolved solids are separated by a semi-permeable membrane, this results in the passage of fluids through the membrane but the retention of dissolved solids in the column to which the pressure is applied. As an effective means of reducing the salt content of water, RO’s main applications are the production of drinking water, ultra pure water and boiler feed water. It also has application in the dairy, food and galvanic industries.

     17 Ibid.

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    4. Nanofiltration (NF) - NF employs a combination of pressure and membranes to effect separations based on molecule size. As such it has many similarities with reverse osmosis (RO). Its predominant application is in the removal organic materials (e.g. multivalent ions and micro pollutants). However, whereas RO is 98-99% effective (at 200psi) in the removal of monovalent ions, NF ranges between 50-90% effectiveness. The range for NF varies according to the membrane’s material and manufacture. Hence, a range of NF membranes exist, each with a specific application. NF’s main application is in drinking water purification, particularly decolouring, softening and removal of micro-pollutants. It also has industrial applications, for example laundry wastewater recycling, pesticide removal from groundwater and the removal of heavy metals from wastewater. In general, NF and RO membranes are effective in the removal of dissolved salts, while MF and UF membranes are effective in the removal of dissolved solids. The smaller the pore size (MF largest - RO smallest) of the membrane, the greater the operating pressure required. For example, MF membranes having the largest pore size can be effective with <200 kPa, whereas RO membranes with the smallest pore size require >1,000 kPa to be effective.

    18, include: Examples of membrane treatment, according to Sydney Water

    - salt removal from brackish or saline solutions RO

    - colour removal in the textile industry UF/NF/RO

    - pulp and paper water recovery UF

    - oily wastewater treatment UF

    - laundry effluent treatment UF/NF/RO

    - boiler feed water treatment UF/RO

    19- landfill leachate UF/RO.

    Whilst membranes are very effective water treatment technologies, membranes can become fouled from suspended solids or covered in scale and salts, if not properly operated. The risk can be reduced by:

    - selecting the appropriate membrane

    - maintaining proper operating conditions (including rate of recovery)

    - cleaning membranes regularly.

    - pre-treating waste (including pH control, dosing with anti-scalant and pre-screening as

    outlined in table 6.1.1) The pre-treatment of feed water for nano-filtration or reverse

    osmosis installations greatly influences the performance of the installation. The required

    form of pre-treatment depends on the feed water quality. The purpose of pre-treatment is

    reducing the organic matter content and the amount of bacteria, as well as lowering the

    MFI. The organic matter content and the amounts of bacteria should be as low as possible

    to prevent the so-called bio-fouling of membranes. The application of a pre-treatment has

    several benefits:

    - Membranes have a longer life-span when pre-treatment is performed

     18 Ibid. 19 Ibid.

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