Published in “Waste & Energy Thailand”, March-April 2008, TechnoBiz Communications Ltd.
Real-Time Monitoring of Membrane Fouling Mohamad Amin Saad, MASAR Technologies, Inc., USA Summary Reverse osmosis process has been established and proven as the technology of choice for efficient and cost-effective brackish and seawater desalination for over 30 years now. In addition, RO and other membrane technologies are technically and economically viable processes to treat and concentrate industrial waste effluents to meet environmental compliance requirements such as zero liquid discharge, contaminant loading ceilings and other applications. However, the commercial application of membrane technologies to desalinate surface brackish and seawaters, as well as purify highly turbid, contaminated effluents such as industrial wastewaters, has been greatly frustrated by the problem of unpredictable and often irreversible membrane fouling, significantly and adversely affecting membrane performance, useful life and ultimately, water cost. This led to understandable perceptions of non-reliability and lack of confidence in the technical, as well as the economical viability of RO and other membrane-based processes for such applications. Addressing the serious and persistent problem of membrane fouling is critical to the future and development of reliable and affordable membrane technology applications. The innovative “Silent Alarm™” technology discussed in this article makes a giant and an unconventional leap in that direction by allowing for real-time detection, measurement and monitoring of membrane fouling and scaling. The issue of fouling Membrane fouling in Reverse Osmosis (RO), Nanofiltration (NF), Ultrafiltration (UF) and Microfiltration (MF) water treatment plants is recognized in the desalination industry as the most critical problem facing membrane technology applications since the advent of membrane process commercialization some thirty years ago. To address this problem, the industry has traditionally relied on evaluating system performance trends in terms of permeate flux and salt rejection. Performance evaluation is conducted analytically by normalizing the membrane system’s operating data using ASTM standard method D 4516 (“Standard Practice for Standardizing Reverse Osmosis Performance Data”). Because this method does not account for significant variations of overall plant operating variables and limitations, especially under low to moderate fouling conditions experienced by the majority of plants, it may not represent the actual performance trends of the plant under these conditions. Consequently, when fouling does develop and accelerate over a period of time in the membrane system, this standard analytical technique may not detect it until it becomes severe or irreversible. At that point, the plant experiences drastic and irrecoverable losses in productivity and quality, resulting in pre-mature and costly membrane replacements.
The crux of the problem has essentially been how to adequately and reliably monitor membrane system performance as to detect the onset of membrane fouling and scaling development in real time and before significant or irreversible loss of performance and equipment occurs. The current industry-wide membrane performance analysis, trending and evaluation methodology based on ASTM D-4516 standard method, has proven to be inconclusive, unreliable and often misleading. It does not measure fouling tangibly nor does it detect its development early enough in order to take appropriate action and prevent its adverse effects. Why is ASTM performance trending not adequate? The analytical trending technique adopted as an ASTM standard in the late Seventies was originally developed by the industry’s global pioneer and leader, DuPont. However, it represents the membrane performance trends only from the membrane manufacturer’s point of view since it is largely based on in-house lab test data and hypothetical assumptions and not on real-life site-specific plant realities such as actual design parameters, operating conditions and other dynamics. By definition, trending requires a statistically valid, and a reasonably large amount of operating data records plotted over a long period of time to establish a definite trend. Field experience at a large variety of membrane plants around the world in the past 25 years shows that it is virtually impossible to detect the early development of membrane fouling in a system simply by monitoring its long-term trends. By the time a definite trend has been established, fouling practically had become too significant (i.e., uncleanable) as to cause an irreversible loss in performance and element damage. This is largely due to the fact that in most cases fouling is cumulative in nature and builds up over a long period of time, just like a cancer in the human body, before it starts noticeably exhibiting its adverse physical effects at the plant. The “Silent Alarm™” Technology To address the critical need of RO, NF and other membrane plant operators and owners to detect and measure membrane fouling or scaling development as early as it starts to occur and to monitor the real performance of their membrane systems in realtime, MASAR Technologies, Inc., USA, has developed an innovative, practical and early-warning approach called the “Silent Alarm™”. The new approach was discovered and developed after many years of closely monitoring and trending the flux decline performance of large seawater and brackish RO plants, especially with a history of biological, organic, colloidal and other forms of membrane fouling that exhibits itself suddenly and becomes irreversible with little or no warning. Many plants which are prone to fouling typically start exhibiting significant and sudden losses in productivity and/or deterioration in product quality when the normalized flux decline or salt passage “trend” has matured, at which point it is almost too late to save the plant. Significant losses in the plant’s performance, availability and consequently, O&M costs, result. The “Silent Alarm™” technology is capable of detecting fouling or scaling development at the onset, and quantitatively measuring it by calculating and plotting both the industry-standard ASTM-normalized flow and a corrected normalized flow, which takes into account actual plant design parameters, site-specific conditions and 2
other dynamic variables. The percentage differential between the two normalized flows, represented by the yellow area in Fig. 1, represents the fouling magnitude of a proprietary parameter known as the Fouling Monitor (FM), and acts as an earlywarning system to benefit plant owners and end-users in optimizing the total cost of produced water. Case History Fig. 1 was developed by monitoring a biofouled RO water desalination plant in the Middle East for over 3 years of operation where no fouling occurred during the first year (only projected flux decline due to membrane compaction). Biofouling started to occur at the beginning of the second year (about 8,700 hours) but was not noted for almost another year (at about 17,500 hours) as the plant continued to deliver betterthan-projected product flow and salinity. At that time, severe, irreversible flow became evident and the membranes deteriorated and had to be replaced.
Fig. 1. Biofouling RO Plant’s Normalized Flux Decline History
The ability of the “Silent Alarm™” method to detect and measure the fouling as soon as it starts to develop (i.e., in real-time) is demonstrated in this case. By measuring and monitoring the FM, the onset of fouling (i.e., when the two curves started to split) could have been easily detected and steps taken immediately to identify and correct the fouling or scaling situation before too late without the need to stop the plant for excessive membrane cleanings or premature and expensive replacements. The degree of variability in the FM with time is used as an on-line fouling indicator over the life of the membranes. During the different stages of this plant’s performance history, the 3
FM went from an average of less than 1.0% during the non-fouling period (first year) to a range of 5.7%-15.7% during the moderate to significant fouling period (second year) to over 20% when fouling became irreversible (third year). In the author’s field experience, FM values of 5% or less were generally found to be acceptable and do not indicate the presence of appreciable fouling conditions in the system. Values ranging between 5-10%, however, indicate some kind of fouling may be starting to develop, while values of 10-20% would indicate that fouling is well underway, especially if the FM continues to increase with time. FM values of 20% or higher certainly indicate heavy fouling conditions are occurring in the system and may already have become irreversible (Table 1). FM RANGE
FOULING STATUS
RECOMMENDED ACTION
0% - 3%
No significant fouling.
Good operation. Continue to monitor.
3%-10%
Low to moderate fouling may be starting to develop.
Monitor more closely. Consider troubleshooting if trend rise continues.
10%-20%
Moderate to heavy fouling is in progress.
Start trouble-shooting immediately to identify and eliminate source of fouling.
Over 20%
Heavy to irreversible fouling is occurring.
Significant membrane replacements required due to extensive loss of possible physical performance and damage.
Table 1. Fouling Monitor (FM) Guidelines
Fig. 2 shows the same plant performance after correction of the biofouling problem and replacement of membranes. It is clear that the two normalized flux decline curves are almost inseparable during the whole period of over 60,000 hours of operation, indicating steady non-fouling conditions membrane replacements and other process and operational changes that resulted in sustaining excellent, non-fouling performance for the last 7 years of operation.
Fig. 2 Non-fouling RO Plant’s Flux Decline History
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The average FM for this period was 1.5%, reaching as low as 0.1% at the end of the period (Fig. 3).
Fig. 3 Non-fouling RO Plant’s Fouling Monitor History ®
MASAR Software A universally-applicable and fully-tested software program known as MASAR® (Membrane Alarm System and Automated Reporter), based on the “Silent Alarm™” technology, was subsequently developed. The MASAR® software system, a standalone desktop application, is available in custom versions such as MASAR®Optima™ for single-pass RO/NF plants, MASAR®Plus™ for double-pass RO/NF plants and MASAR®Ultima™ for UF/MF plants. A monthly in-house plant monitoring and evaluation service is also available requiring only e-mail transmission of train operating data files in order to deliver a full performance evaluation and fouling status report, complete with recommendations for action if required. A earlywarning alert is also sent to the plant in case fouling or scaling development is detected. Program Applications Serving as a real-time, early-warning performance, fouling and O&M cost monitoring and optimization tool, as well as an integrated plant data management & reporting system, the program’s operating data input is based only on the same design & operating data parameters required by ASTM D 4516. The new methodology and software program apply universally to any water desalination or purification membrane plant (for drinking & industrial end-use applications) with: ♦ ♦ ♦ ♦ ♦
Brackish, high brackish, seawater & wastewater feed sources. RO, NF, UF or MF membrane process. Single or multi-brine-staged systems. Single & double-pass systems (i.e., UF/RO). Multiple numbers of trains or skids. 5
♦
Any membrane manufacture, model, material (cellulose acetate, polyamide or polysulfone), configuration (spiral-wound and hollow-fine fiber) and design configuration and layout (brine or product staging and number of membrane cartridges per pressure vessel).
The program is especially valuable for R&D, product development and pilot testing monitoring & optimization, such as those conducted by water treatment chemicals suppliers, academic institutions and industrial research labs. The instant, real-time response of the system is critical in measuring, evaluating and monitoring the true efficacy of membrane cleanings, chemical dosing systems and impact of on-line changes in design, process or operational parameters in the field. This allows the maintaining of the system dynamics while different process and operating parameters are tested. The program also monitors and displays, in graphical and report forms, the operating membrane flux (feed or product flow per unit membrane area) as well as the MASAR®-calculated flux that serves as another real-time indication of fouling development potential, especially in UF and MF membrane systems designed as pretreatment to RO or NF plants. “Silent Alarm™” Benefits 1. Monitors your plant's operational and performance fouling status in real time, not as a long-term trend. ¾ By monitoring the Fouling Monitor (FM), the plant operators can continuously check the membrane system's operation status and detect any adverse performance changes or deterioration, such as biofouling, colloidal fouling, silica or chemical scaling, as early as they develop in the system and long before they are exhibited at the plant. ¾ Unlike the standard normalization method (ASTM D 4516), used by all membrane manufacturers and required by them as a condition of membrane system performance warranties, the FM measures and shows the actual performance of the membrane system on a day-by-day basis (i.e., in real-time), not as a long-term trend that cannot be fully determined or utilized until it is too late (i.e., when severe fouling effects are exhibited at the plant resulting in significant plant performance, availability and cost losses). 2. Detects and measures fouling and scaling development, and gives the operator early warning and recommends proper action before too late. ¾ If the system is beginning to foul or scale, plant managers, engineers and operators are prompted to take immediate corrective action while the plant is still performing according to or above design values, and months before significant or irreversible loss in performance characteristics are experienced.
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3. Helps achieve the most attainable optimum conditions for your system operation. ¾ If the system is not fouling and performing as designed or better, it confirms the non-fouling conditions everyday and allows the operator to determine if the plant is actually running at the most optimum conditions without having to wait for a long-term trend to develop and be analyzed. ¾ Helps optimize and achieve the maximum attainable membrane system recovery ratio and other critical operational parameters by monitoring the true fouling potential as the recovery ratio is incrementally increased to the maximum level allowed by feed water chemistry and system limitations. Most RO plants operate well below their maximum recovery ratios because of warranty limitations, changing water conditions or fear that the system will react negatively and cause problems. 4. Shows the true effect of design, process and operational changes, membrane cleanings, additions and replacements, and chemical treatments. ¾ By monitoring and measuring the actual system performance on a daily basis, NOT as a long-term trend, it allows the plant operator to determine the true need for cleanings, membrane additions or replacements, change of disinfectants or anti-scaling chemicals or other process and operational changes. ¾ As a truly independent system, MASAR® is especially effective in comparing different membrane performance under the same dynamic plant conditions. When the plant changes the membrane manufacturer and replaces membranes on a train, for example, it will be able to compare the actual performance and fouling tendency of the new membranes versus the old ones, and make an informed decision on which ones work better for this specific application. ¾ Most RO plants follow a rigid, pre-set schedule for system maintenance, especially for cleanings and membrane replacements or additions, not taking into account the actual system performance at the time, but MASAR® lets you reliably determine if there's a need for such maintenance at any time, and helps save you significant expense from unnecessary or ineffective cleanings, chemicals, labor and other O&M costs. ¾ MASAR® is useful in testing and optimizing the effectiveness of new treatment chemicals such as coagulants, anti-scalants and biocides, either on pilot systems or on actual plant. It also helps test new processes or equipment (such as microfiltration) and their impact on RO performance and cost.
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5. Differentiates between flux decline caused by either membrane compaction or by fouling/scaling. ¾ Because MASAR® monitors the FM, as the only sensitive and early indicator of fouling, by taking the difference between two normalized product flows, it actually can tell if the decline is due only to compaction (i.e., FM remains low but the two normalized flux curves decline stay together), or due to fouling or scaling (i.e., FM increases significantly in a short period as the two normalized flux curves split). This is important because most RO plants which monitor their normalized flux decline curves cannot distinguish between the two effects, leading them to believe that they have a fouling problem and starting unnecessary membrane cleanings, additions, etc., while the problem is only that the decline is due to membrane compaction higher than projected by the membrane manufacturer or designer. ¾ A recent case history study at an RO/NF brackish demonstration plant in California (Ref. 6) showed that MASAR® actually indicated through different responses to biofouling measurement that a set of NF membranes had a membrane manufacturing defect as compared to an identical RO set that was free of any defects. 6. Acts as the plant's fully-integrated performance, fouling, O&M cost monitoring and data management & reporting system. ¾ MASAR® software system is designed so that the operator can easily and selectively produce professional plant operating and performance history reports and graphs for each train, stage and operating hour/date range. ¾ The system maintains 2 user-accessible databases for storing operating data records and for performance results summaries. ¾ Data entry can be performed manually by the operator, downloaded automatically from the plant's data acquisition systems, or transferred directly from any membrane manufacturer's normalization program files. ¾ MASAR® software is highly user-friendly and error-proof. It does not accept or save invalid or erroneously entered data and prompts the user to correct the problem immediately to avoid system failure. ¾ The system applies universally to any membrane-based water desalination or purification plant with any end-use application, feed source, membrane type, material, manufacture, configuration or system array. 7. Helps plant owners and end users operate and maintain the most efficient, optimum-performing membrane desalination plant at the lowest water cost by: ¾ Significant reduction in operational downtime. ¾ Significant reduction in fouling potential. ¾ Significant reduction in maintenance requirements. 8
¾ Significant reduction in O&M costs. ¾ Significant improvement in plant data management. MASAR® Program Flow Fig. 4. shows the Silent Alarm™ program’s flow chart. The program’s menus and screens have been designed for maximum simplicity, logical flow and ease of data entry, editing, display, reporting and charting in three distinct functionalities: Plant & Train Design Operating History Performance Monitoring
Fig. 4. MASAR® Program’s Flow Chart
Plant & Train Design The software is designed on a single-plant basis. Licensed plant’s basic design information is entered in the Plant Design screen, and the user can view and print a summary report but cannot change any of the information. Upon installing the program on the user’s computer (typically at the plant site), the following information must be entered by the operator, via the Plant Information menu, only once, or can be pre-entered in the license installation CD-ROM: ¾ Design configuration of each existing train. ¾ Standard units used in design projection. ¾ Operating units used at the plant. ¾ Standard or design conditions for each train (per stage if system is multi-staged and inter-stage data are available).
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Standard conditions (i.e., basis for normalization) can be easily modified by the operator at any time via the Edit Standard Conditions screen.
Fig. 5. Edit Standard Conditions Screen
Operating History A. Data Entry, Import & Conversion options a. Manual entry of parameters via the Enter Operating Data screen. b. Manual transfer of historical data records from existing spreadsheets (i.e. MSExcel®), databases (i.e., MSAccess®) or from data files of any of currently-available membrane manufacturers’ normalization software programs (i.e., DuPont’s NormPac®; Hydranautics’ ROdata®; Koch Membrane Systems’ NormPro®; Dow Filmtec’s ROSA®). c. Automatic transfer of data from data acquisition systems (i.e., SCADA), which requires simple configuration of its output so that it is transferred to the corresponding fields in the operating data table. d. Any combination of the above. B. Data Validation & Edit The program features a very rigorous and user-proof data validation regime to ensure that only valid, logical, complete and consistent data are entered into the system to minimize runtime errors and other failures. Data records entered manually by the operator, for example, are checked and verified before it is saved into the database. Negative, bad or zero values, as well as missing required operating parameters (Table 3) are 10
flagged instantly in a simple pop-up screen message, alerting the operator to the error so that it is corrected. Data manually or automatically downloaded or transferred into the operating database are checked and verified every time the operator executes any functionality in the operating history or performance monitoring menus. In such cases, the operator gets a simple message alerting him/her of the error and prompting review and corrections of the bad data via the Edit Operating Data screen.
Fig. 6. Edit Operating Data Screen
Table 2 shows a list of required and optional design and operating data parameters. Table 2. Required & optional data parameters REQUIRED PARAMETERS
OPTIONAL PARAMETERS
1.
Train or skid name.
1.
Feed turbidity (NTU).
2.
Stage number.
2.
Feed SDI.
3.
Date data collected.
3.
Micron filter pressure drop.
4.
Operating hour.
4.
RO feed pH.
5.
Feed temperature.
5.
Redox Potential (ORP).
6.
Feed salinity or conductivity.
6.
Chlorine residual.
7.
Feed pressure.
7.
Others (customized).
8.
Membrane pressure drop.
9.
Permeate pressure.
10. Final reject flow. 11. Permeate flow. 12. Permeate salinity or conductivity. 13. No. of pressure vessels on-line. 14. No. of membrane cart. per P.V. 15. Membrane area (per cartridge)
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Fig. 7. Operating History View Screen
C. Data Display, Reporting & Graphing: Entered and imported operating data, selected by train, stage and operating hour range, can be viewed in a summary screen, accessible from the Operating History menu (Fig. 7). Time profiles of key operating parameters such as feed temperature, feed salinity, feed pressure, feed flow, conversion (recovery ratio), membrane pressure drops (Fig. 8.a), product flow and product salinity (Fig. 8.b), can be charted with options for printing, statistical analysis and exporting. For double-pass and brine-staged systems, the same viewing, graphing and reporting can be conducted for each pass and stage, as well as for the overall system (i.e., train or skid).
Fig. 8a. Membrane Pressure Drop Profile
Fig. 8.b. Operating Product Salinity Profile
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The same data can be produced and exported in a report format (Fig. 9).
Fig. 9 Operating History Summary Report
D. Data Security and Utilities Licensed users are provided with their own password to limit access to the program and data to authorized plant personnel. The program provides for easy database backup and emergency recovery screens in case of software or system malfunctions, virus infection incidents, computer/hard drive upgrades or catastrophic failures. The user can also compact the operating and functional databases at any time to maximize storage space capacity. Performance & Fouling Monitoring Upon selection by the user of the set of data to be monitored or evaluated by pass, train, stage and range of operating hours, the program calculates and displays a summary of each record’s normalized flows (ATMS and corrected-ASTM), Fouling Monitor and ASTM-normalized salt passage. A status message is also displayed, with the average calculated FM of the data set, to alert the operator of the preliminary conclusion based on the practical FM guidelines listed in Table 1, together with 13
recommendation for action if necessary (i.e., continue to monitor, start troubleshooting, etc.). The operator can then view in graphical and report formats (Fig 10, 11 & 12).
Fig. 10. Performance Monitoring Summary Screen
Fig. 11. Performance Monitoring Flows Graph
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Fig. 12. Fouling Monitor™ during the acid dosing trial of Penneshaw SWRO Plant, Australia (Ref. 1)
For double-pass and brine-staged systems, the same evaluation can be conducted for each pass and stage, as well as for the overall system (i.e., train or skid). This helps greatly in identifying and locating the source of fouling or scaling in the system should it start to develop. Testimonials & Plant References Since it was in the development and beta-testing stage, the program has been extensively tested and validated throughout, using actual data from membrane plant installations worldwide. The US-based DuPont’s Permasep® Products, the world’s pioneer in membrane technology applications for drinking and municipal applications, and original author of the ASTM D-4516 RO performance evaluation procedures, conducted an independent 9-month field evaluation of the new technology and software system in the Middle East and USA. A letter was subsequently received from the Product Manager at Permasep Products®, stating that “we agree with your findings that MASAR®, when properly applied, is an excellent tool to monitor plant performance and capable of providing an early warning if membrane fouling is occurring”. He added that “this technology could be very useful to RO plant owners and operators”, and that “Permasep® Products approves and recommends the use of your MASAR® software technology applied to RO plants using our membrane products”. Since then, the program has been successfully installed, evaluated or specified at more than 20 major seawater, brackish and industrial wastewater RO, NF, UF and MF plants in Saudi Arabia, United Arab Emirates, Malta, Australia, Singapore, 15
Malaysia and the United States. Recently, the Saudi Saline Water Conversion Corporation (SWCC), the largest producer of desalinated water in the world, as well as Saudi Aramco acquired license to the software to monitor their strategic seawater and brackish RO plants. Conclusion With membrane technology applications exploding in growth and utility around the globe, the need to address the problem of monitoring and evaluating membrane desalination plants performance, fouling development and operational costeffectiveness becomes ever so critical. New mega plants are already operating or coming on line, or being designed or conceptualized in the new millennium, such as the 90,000 m3/d seawater RO plant in Al Jubail, Saudi Arabia, the 142,000 m3/d seawater RO plant in Al Fujairah, UAE, the 109,000 m3/d Point Lisas seawater RO plant in Trinidad, the 24 MGD seawater RO plant in Tampa Bay, Florida (with another 24 MGD plant planned for the same district in the near future), the 25 MDG seawater demonstration plant in Corpus Christie, Texas and the 45 MGD seawater RO plants planned by the Metropolitan Water District of Southern California. Reliable performance and availability of these plants, for example, at minimum operating and maintenance costs are mandatory. The new Silent Alarm™ program can provide these plants and many others a unique tool to help them achieve these objectives on a daily basis. References 1.
Pelekani, Con, Jewell, Sarah Ann, Kilmore, Geoff, South Australia Water Corporation, “Design, Operating and Research Experience at the Penneshaw Seawater Desalination Plant”, 2007 IDA World Congress on Desalination & Water Re-Use, Gran Canaria, Spain.
2.
Saad, M.A., “Pushing The Limits: Optimizing Membrane Plants Via Correlating Fouling with Critical Flux”, presented at and published in the proceedings of the International Desalination Association’s Congress on Desalination & Water Re-use, Singapore, September 2005, IDA, Massachusetts, USA.
3.
Saad, M.A., “Early Discovery of RO Membrane Fouling and Real-Time Monitoring of Plant Performance for Optimizing Cost of Water”, presented at and published in the proceedings of EuroMed 2004 Conference on Desalination in Southern Mediterranean Countries, Marrakech, Morocco, May 30-June 2, 2004. Desalination 165 (183-191), February 2004, Elsevier Science Publishers, Amsterdam, The Netherlands.
4.
Saad, M.A., “Manufacturer’s Case Study: Smart Software Optimizes Membrane Plants” –International Desalination & Water Reuse Quarterly, August/September 2003, Vol. 13/2, pp. 45-49, Faversham House Group Ltd., UK.
5.
Saad, M. A., “Optimize Water Cost By Early Prediction of Membrane System Fouling Trends”, Presented at and published by the 1999 IDA World Congress on Desalination and Water Re-use, Session 5B – Membrane, Fouling & Chemical Studies, San Diego, California, USA, August 29 September 3, 1999. Richardson, Joe, Port Hueneme Water Agency, Port Hueneme, California, USA; Saad, M. A., MASAR Technologies Inc., Tucson, Arizona, USA, “Real-Time Membrane Fouling Monitoring A Case History”, Presented at and published by Water World™’’s World of Water Conference, Las Vegas, Nevada, USA, December 10-13, 2001.
6.
7.
Pursley, Kathy, “Software Warns of Early Membrane Fouling”, Industrial Water World™, Automation, Vol. 03.01, p. 13, Jan./Feb. 2002, PennWell®.
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About the author
Mohamad Amin Saad has a B.S and M.Sc. in chemical engineering from Georgia Institute of Technology, Atlanta, Georgia, USA. During the past 25 years of his professional career in the water desalination and membrane technology applications, he has gained tremendous technical and practical field experience in RO plant design, startup & commissioning, operation optimization, performance evaluation, trouble shooting and membrane fouling identification and prevention, particularly in the Middle East, Europe and USA, and published several international technical papers. He has also designed and conducted numerous membrane desalination technology in practice seminars, workshops and courses for plant operators, engineers and managers. Mr. Saad worked as a Senior Technical Specialist with DuPont, as a Membranes Development Manager with Aqua-Chem and as a Technical Marketing Director at Biosphere 2 Environmental Project in Arizona before starting his own consulting, training and plant monitoring software development and marketing firm in Tucson, Arizona. He can be reached by e-mail at
[email protected] or via the company’s web site www.masar.com..
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