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Proceedings of the ASME/USCG 2010 2nd Workshop on Marine Technology and Standards MTS2010 July 29-30, 2010, Washington, DC, USA MTS2010-0207 EMERGING TECHNOLOGIES FOR TREATING CONTAMINANTS IN MARINE WASTEWATER Don Nguyen Coffin World Systems Irvine, CA, USA ABSTRACT contribution. Historically, oily bilge water has been treated using Oil/Water Separator technology (OWS) Contaminants in marine wastewater facing current or or discharged with minimal treatment. Bilge water is near-future regulations can be broadly categorized to not exactly water but a of varied amounts of Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 free oil & suspended solids, emulsified oil and fresh water, sea water, oil, sludge, chemicals and dissolved solids, and biological organisms. The first various other fluids. Sea water and fresh water can category of contaminants has been treated by find its way to the bilge wells due to leakage in the commercially available OWS systems. The second pipe lines, leaky pump and valve glands, from class of contaminants, emulsified oils and dissolved machinery, propulsion system, over flowing of tanks solids, has been effectively treated by UF membrane and even due to accidental spills. All these substances filtration and to a less extent by biological oxidation get accumulated in the bilge wells and the mixture and surface modified filters. A survey of recent formed is known as bilge water. Currently all advances in physical and chemical demulsification overboard water has to strictly comply with MEPC technologies to enhance emulsified oil removal with 107/49 as specified by IMO and MARPOL, which sets reduced loads on membrane was conducted. The the limit for all oil discharges, free and emulsified, to study also identified new applications for treatments of less than15 ppm. biological organisms in ballast water. A variety of technologies have arisen to fill the gap NOMENCLATURE between OWS Capability and discharge standards. Among these are systems based on gravity separation, BOD Biological Oxygen Demand, mg/l or size separation, chemical affinity separation and ppm flocculation. There has also been a gap between COD Chemical Oxygen Demand mg/l or regulation and enforcement. Unregulated discharges ppm have been problematic. There have been significant CM Coalescent Media advances in the ability to detect such discharges in the DAF Dissolved Air Flotation past few years; the most significant is Synthetic HLB – Lipophile Balance Aperture Radar (SAR). This paper will review IMO International Maritime Organization developments in oily bilge water treatment. IAF Induced Air Flotation MARPOL Marine Pollution, International REVIEW OF BILGE WATER PROPERTIES Convention for the Prevention of Pollution from Ships, 1973 as AND ESTABLISHED TREATMENT modified by the Protocol of 1978 TECHNOLOGIES MEPC The Marine Environment Protection 1. Survey of Bilge Water Composition Committee OWS Oil Water Separator TDS Total Dissolve Solids, mg/l or ppm A survey of more than 40 bilge samples indicated that TSS Total Suspended Solids, mg/l or ppm most solids are in dissolved form (average TDS= TO&G Total Oil & Grease or n-Hexane 18008 ppm). TDS includes dissolved oil, the majority extractable materials, mg/l or ppm of emulsified oil, dissolved COD & BOD, salts, and a US Ultrasound small fraction of dissolved metals. TSS is derived from of silt, rust, sand, grits, and even red clay. INTRODUCTION Some major Bilge Water compositions are listed in Table A. There is lacking of any typical values for A bilge is the lowest space of a ship. It is the area bilge properties. For example, TSS can vary between where two sides of the ship meet. Of the oil released 1000 ppm and 38,000 ppm, depending on the ages, by vessels, 25% is reported to come from spills and sizes, and crew practices of the vessels. The average 75% from operational discharges. Oily bilge discharge fraction of emulsified oil can be estimated to be about is second only to oily ballast tank discharge in its 30% of the total TO&G. 58 Published with permission. Table A: Properties of Bilge Water Based on Table B: Activity Based on HLB more than 40 Bilge Samples Appearance in Water HLB Range Average , Range, No Dispersability 1-4 ppm ppm Poor Dispersion 3-6 TDS 18000 1000 - 38000 Milky Dispersion After 6-8 TSS 900 40 - 16000 Agitation Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 TO&G 1100 20- 46000 Stable Milky Dispersion 8-10 C6 N D 200-400 Translucent To Clear 10-13 C10 250 0-8000 Clear 13+ C22 0-18000 Fe 15 1.4-43.4 As oil droplets coalesce from smaller to bigger sizes, COD 70-11000 they impart significant color change from gray, bluish- BOD 5-15000 white, to milky white. The color change can be used to classify into broad categories of water-oil Size distributions of solids from limited number of such as gray, bluish, or white oily water (Table C). samples were found to vary from normal to bimodal distributions with the median vary between 15 µm to Table C: Color of Based on Particle 60 µm. Sizes

Bilge water is a chemically complex mixture of Particle size (µm) Emulsion appearance , surface active agents (, i.e. soap), Macro globules Droplets may be visibly metal salts such as greases and lubricants and tramp >150 µm distinguished oils (i.e. compressor condensate). Some of the above 10 µm-100µm Milky white emulsion are polyaromatic hydrocarbons and chlorinated 1.0µm-10µm Bluish-white emulsion aromatic hydrocarbons. Others such as aromatic 0.05µm-1µm Smoky gray, semitransparent hydrocarbons and oil, copper, iron, mercury, zinc and <0.05 Transparent micro emulsion nickel, organic metal salts in addition to and solvents are aquatic toxins. 2. Review of principles of OWS (Oil Water Generally speaking organic non-polar compounds Separator technology) (oils) are not soluble in water. However if solids, solvents or surfactants are present, oils will tend to Oil water separators are gravity separation devices emulsify in water. The degree of emulsification is which utilize a difference in buoyancy of two inversely proportional to the buoyancy of the . immiscible liquids to achieve separation. For oily bilge If sufficient emulsification occurs to achieve neutral or water, the separation is of the dispersed oil droplet closed to neutral buoyancy gravity separation devices from the continuous water phase. All chemical and lose their effectiveness in separating the organic mechanical methods of oil separation conform to compounds from water. One way to gauge the relative Stoke’s law: of a surfactant and thereby the type and stability of the emulsion is the HLB (Hydrophile – 2 Lipophile Balance) method (9). In this method a V = [2(ρo- ρw) g R ] / [9µ] number between 1 and 40 is assigned to many V = oil droplet rise velocity commercial emulsifying agents, which is indicative of ρo- ρw = Oil –water density differential the balance of hydrophilic to lipophilic portions of the R = Mean radius of oil droplets . The higher the HLB, the more water-soluble µ = Water viscosity the material becomes (Table B). The water solubility o of an emulsion or a surfactant can be used to make an Typical and oil at 30 C were used approximation of its HLB which is indicative of the to estimate the rising velocity of oil droplets as a stability of the emulsion. function of droplet sizes. The following graph indicates that the rise velocity becomes much faster for larger droplet sizes (Figure 1).

59 Figure 2: Coalescent Media (CM) Manufactured by Figure 1: HD-QPAC and Brentwood Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021

Traditional OWS equipment is mostly effective when oil and water are presented in two discrete phases. Oil particles have a natural tendency to aggregate on contact. The momentum for collision has to be minimized to prevent the breakup of the larger oil droplets since oil surface tension is much lower than water. It is therefore important to maintain a laminar flow with a Reynolds number within 50 for the separation based on Stoke’s law to be dominant. Oil aggregation is enhanced by coalescing media. The coalescent media (CM) has surface properties that are not only hydrophobic but also oleophilic. As the oil droplets contact the CM surface, a new CM-oil interface is preferred to oil-water interface. The media provides oleophilic surfaces for a deposit of oil droplets as long as the surrounding flow is gentle or laminar. Oils droplets increase in sizes by absorbing Brentwood CM has cross-hatched channels at angles each other to minimize the droplet surface areas. A of 600 to 90o to vertical (Figure 2). Channeling threshold is reached when the droplets are large occurs if the connecting holes between cross hatched enough for the buoyancy force to overcome the media channels are plugged up over times. CM close to the surface affinity. This happens when the droplet inlet can be under-utilized if this occurs. CM should diameters are in the ranges of 40-60 µm. The oil have as high as possible surface area/volume. Too droplets rise to the water surface to be separated. high surface area can lead to plugging because of When emulsification or occurs buoyancy grease and sludge blocking of the narrower flow differences are too small to be separated by the gravity channels. HD-QPAC CM is designed to have flow o differences. Upstream pretreatment or downstream channels at 90 to vertical dripping rods. HD-QPAC polishing technologies are required to meet the claims to have very high surface areas with a low risk discharge limits. In all cases, the surfactant shields on of plugging thanks to the more opened flow channels. oil droplets must be at least partially broken to expose Common ranges for OWS coalescent matrix are from the oil surfaces for the traditional OWS to work. 60 ft^2/ft^3 to 130 ft^2/ft^3 of CM.

60 3. Emulsion Breaking or Demulsification oil removal efficiency, but can remove significant amount of bigger size sand and grit particles. Oil emulsification is induced by mechanical agitation with chemical agents. When oil exists with mixtures of Table D: Process Conditions for Different solvents, soaps, greases, lubricants, and tramp oils, Flotation Processes mechanical are created through the process Flotation Air Size of Input Est. Hydraulic of pumping, large pressure drops through chokes and process flow bubbles power Retention surface control valves. The emulsions are further stabilized by l.m-3 Wh time, min loading Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 surfactants added in the industrial or cleaning water /m3 mh-1 processes. Chemically emulsified oils need to be Macro air 100- 2-5 mm 5-10 5-15 10-30 destabilized to liberate free oil so that the oil will flotation (grease 400 separate by gravity or flotation. Once the emulsion is removal) broken, the same removal techniques applicable to free IAF (froth 10.000 0.1-2 60-120 4-16 oil can be utilized. flotation) mm DAF 15-50 40-70 40-80 20-40 3-10 3a. Mechanical Demulsification (clarification) μm (excluding flocculation)

Heating the emulsion to 60 oC followed by several 4. Chemical Demulsification hours of settling would break the poorly emulsified oils. This approach can be economical where waste Oil can have anionic (-) or cationic (+) surface charges steam is readily available. Most of the time, a limited depending on the kind of detergents or surfactants. heating of the mixture would assist other Most oil emulsions have anionic surface charges. demulsification methods by weakening the bond Neutralization of the surface charges breaks the between the surfactant envelopes and oil. Another emulsion. approach includes flotation which reduces the apparent density of oil and dirt by coupling these particles with  Calcium or magnesium salt can be added to air bubbles (Table D). emulsion stabilized by sodium soap. Emulsion

is broken when Ca++ and Mg++ replace Na+ in Dissolved Air Flotation (DAF): Deoiling is the soap. caused by changing the apparent density of dirt  Other inorganic demulsifiers are ferric and particles and oil droplets, both emulsified and free. aluminum chlorides. They lower water pH Water is supersaturated with pressurized air at 40 psi- and break the emulsion. 80 psi, and then metered to the flotation chamber. Air  Aluminum sulphate adds ionic strength and bubbles, 20µ-120 µ in size, are generated by the modifies surface charges. sudden expansion through the DAF nozzles. The  or acetone break emulsion by bubbles coalesce with oil and dirt to form aggregates, dissolving and removing emulsifiers from the which rise to the surface to from a sludge layer, thanks oil phase to a much reduced density. The floating sludge layer can be skimmed off the surface. The nozzles and air- Significant amount of sludge can be produced and the saturated water can be replaced by DAF pumps such storage and disposal may be issues for some vessels. as Nikuni or Edur pumps. DAF pumps consistently Consistent success of application depends on skill produce fine sizes of bubbles (10 µ-50 µ). They are levels of the operators. Typical OWS systems using particularly valuable if they can tolerate solids up to chemical demulsification are the Jowa and the 100 µ size. Marinfloc. Jowa is a Norwegian-made Emulsion

Breaking Unit with models ranging from 0.33 m3/hr- Induced Air Flotation (IAF): Compression air 1.33 m3/hr. Its operation is mostly in batch mode. is sparged through the chamber bottom. Air bubbles Chemical addition includes solid demulsified agent up to 1-2 mm coalesce with oil and dirt on the way to and NaOH. Approximately 80% removal of the top. They form a froth layer which can be emulsified of was claimed by the vendor. In the skimmed off. IAF is less efficient than DAF in overall Marinfloc, emulsion breaking is induced by using

61 forced flotation & flocculants. It can be used to “MYCELX”) which have affinity for partially pretreat the MEPC 60(33) OWS systems. emulsified droplets (1). MYCELX is belonging to a Together, the vendor claims that effluent with less polymer family synthesized by linseed oil and methyl than 15ppm of oil can be produced. methacrylate. MYCELX is generally used post-OWS to remove highly emulsified materials (Figures 3-6) and to bring the effluent to below 1 ppm. MYCELX has affinity for organic compounds

EMERGING TECHNOLOGIES IN THE Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 and do not develop additional differential pressure in TREATMENT OF OILY BILGE WATER the presence of very thick oils or under high loading conditions. Another advantage of these units is the oil Emerging technologies in regard to oily bilge water seems to be undiminished with time, treatment are usually add-on systems either upstream allowing a more compact system. For the same size, a or downstream of the OWS, as gravity separation is unit can handle influent over 2000 ppm optimal as a first step for bulk removal of non-aqueous and at flow rates varying from 5gpm-150 gpm without phase components. affecting the oil concentration in the effluent which will remain at well below 5 ppm. The spent filters can 1. Biological oxidation be used as an alternative fuel if feasible. The disadvantage of this unit is that the spent filters cannot An oily water separator commissioned by Ensolve be discarded into the sludge tank without shredding. Biosystems under the trade name PetroLiminator 630 MYCELX capability to sequester emulsified oil may uses bioremediation to treat bilge water (1) . Ensolve be limited at room temperature. Complete emulsified claims that their system is capable of reducing oil in oil may not adhere well to the polymeric surfactant. the discharge to about 1ppm- 2ppm. The system Pretreatment with heat or some chemo-mechanical eliminates emulsified oil, grease and other demulsification steps may be required for a complete contaminants using naturally occurring bacteria. emulsified oil removal. MYCELX claims to absorb Although the same technology has been used for many emulsified oil up to 65% of filter media weight using years in land-based applications, this system is the first to be adapted for the marine application. The system 5µ MF and the flow rate is unaffected by degree of oil is designed for continuous duty up to 20 tons/day saturation. capacity, supposedly with minimum maintenance. The operation includes three phases: 1) Free oil 2b. RPA: Similar to the MYCELX, the TORR separation using conventional technology such as (Total Oil Remediation and Recovery System) coalesce media. 2) Biodigestion of the remaining oil process marketed by EARTH Canada uses a using bacteria. A matrix is used to affix the oil- polyurethane- base polymer in the shape of granular scavenging bacteria to prevent wash-out, and 3) a pellets to absorb oil (2). The pellets have a trade name holding tank to complete the process of RPA (Reusable Petroleum Absorbent). RPA is claimed to be capable of absorbing partially emulsified While biological systems can meet the proposed BOD oil droplets, coalesce them to bigger sizes, and eject discharge limits of 26 ppm, the effluent of the them upon saturation under pressure (3). The cycle biological process contains a high concentration of can be repeated about 100 times before the RPA needs non-biodegradable organics which do not consistently replacement. Similar to MICELX, RPA can coalesce meet the proposed limits for COD (Chemical Oxygen completely free oil. The capability to absorb Demand) and TOC (Total Organic Carbon) when emulsified oil may be limited. A crack in the exposed to high-strength oily bilge water. This surfactant shields surrounding the oil droplets is necessitates post bio-oxidation treatments like required for the progress of absorption to the polymer. Advanced Chemical Oxidation.

2. Surface Modified Filtration Devices 3. Oil Coalescing by Ultrasound

2a. MYCELX: Granular substrates and Early work by Sinker et al. (4) has identified that absorbents or cartridge filters can be modified with significant coalescence can be achieved within short “curable polymeric surfactants” (referred to as

62 timescales using ultrasound (US). The acoustic power and frequency levels have to be optimized for a flow at a Reynolds number well within the laminar regime.

Besides Reynolds number, the US effects tend to decrease at higher continuous phase viscosity, but intensify at increased drop size and concentrations. Development of the technique has progressed from lab Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 based batch, bench-top testing with manual frequency control to the use of pilot flow cells in the field with 0 sec, 5 sec, 5-10 sec, automated frequency tracking. US on US off US off Figure 4: The 20mm wide is viewed from above US energy separation utilizes acoustic standing wave, with the transducer on the left hand side: (a) shows the which can be created by reflecting the waves upon initial untreated sample (vol. median drop size ~ themselves at the same frequency. Tuning the system 10μm), (b) reflects the conditions after 5 seconds of to create resonance is essential to generate the nodal applying the standing wave, (c) shows oil drops > and the antinodal zones, where emulsified oil droplets 1mm floating to the surface a few seconds later after are bounced vigorously on each other to expose the the power had been switched off. The 20mm cells are free oil surfaces. The US treatment is followed by an equipped with transducer attached to the left hand inactive section, where the free oil surfaces are in side. Oil droplets grew from 10 µm to ~1mm in contact in a laminar flow to coalesce into bigger oil 5seconds -10 seconds, view from above. droplets (Figure 3). US-induced coalescing is a non-intrusive treatment which requires no pressure and chemicals. Maintaining the resonance field in a section 24/7 requires a precise frequency auto tracking. The impact of resonated mechanical energy may require special reinforcements to the US section to prevent structure damages over a prolonged period.

4. Membrane Bioreactor (MBR)

The Hamworthy KSE (HKSE) membrane bioreactor (MBR) is a development based on the digestion of organic waste by aerobic bacteria (5). Continued development of membrane materials specifically for

the treatment of marine wastewater streams has Figure 3: Illustration of the nodal and antinodal planes resulted in units that are able to operate at a much created by standing wave lower trans membrane pressures (TMP) and have good anti-fouling surface properties. Hamworthy have Collection and growth in the size of oil droplets from a chosen to use tubular membranes, using 8 mm produced water sample through 5 seconds of US nominal bore tubes, mounted into 200 mm nominal treatment is illustrated in Figure 4. diameter fiber reinforced casings. The membranes are rated in the ultra-filtration range, with a nominal pore size of 40 nano meters. Control of non-biodegradable material, or slow to degrade fibrous material, is accomplished by a 200 to 400 micron self cleaning filter. The system is arranged with a primary bioreactor to reduce the incoming organic materials by the action of the concentrated biomass. The effluent particle loadings are further treated with a self-

63 cleaning filter before transferring to a second stage pretreatments and periodic cleaning are required to reactor. The clarified layer from this second stage is extend the operating period to an acceptable range. fed to a membrane module. A proportion of Combined Centrifugal separator/Membrane concentrated biomass is returned to the primary Ultrafiltration systems have also been investigated for bioreactor to maintain a balanced biomass. treatment of large volumes of bilge water that contain high concentrations of emulsified and free-phase oil, These units can be exposed to activated sludge for as well as suspended solids. extended periods. The use of a membrane at the Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 clarification stage provides a physical barrier that Membrane filtration will continue to be the most guarantees effluent quality. A bioreactor operating dependable treatment for marine oily wastewater, with a biomass suspended solids of around 20 g/l is especially for the smaller vessels. The technology is capable of achieving significant BOD5 and COD facing competition from other emerging technologies. reduction. The rate of organic sludge growth is related The UF membrane needs to be protected by better to the ratio between the organic content of the front end treatments to remove most particulates and incoming flow to the amount of active biomass in the oil to reduce the costs related to membrane cleaning. bioreactor. The use of relatively high levels of biomass New membrane technology with surface chemistry suspended solids ensures that this ratio is kept low, more resistant to fouling should be considered. and hence the amount of generated sludge. Backflushable and self-cleaning membrane modules should be incorporated. In general, a much more Typical effluent analyses were: robust deoiling system can evolve if the membrane is used primarily as the final barrier to meet compliance. Total suspended solids <2 mg/l Technologies are available to enable the membrane to Organic content BOD5 2 mg/l perform for weeks on end without cleaning since the Fecal Coliform 13 counts/100ml membrane is functioning primarily as the last polishing step. All results were within the criteria set by IMO and USCG, and full certification has been granted. The HKSE system does not use any disinfectants, i.e. 6. Ballast water chlorine addition, depending entirely on the performance of the bioreactor and membrane to eliminate bio-organisms from the effluent. The Similar approaches can be used to treat ballast water bioreactivity seems to be less efficient for synthetic contaminated with oil. However, from the point of grease and tar. Some oil ingredients in the feed are view of regulators, the greater concern with ballast even toxic to the biomass, resulting in surges of high water is the possibility it might be carrying invasive BOD5 in the treated effluent. species from other parts of the world. Adherence by ships to regulations for total exchanges of ballast water 5. Membrane Filtration (Ultrafiltration) at sea is problematic for many reasons. Moreover, the internal structures of ballast tanks can make it unlikely Ultrafiltration has been considered to be a reliable that even total ballast water exchanges will eliminate separation process for the small-scale treatment of oily all invasive species. bilge water. The systems consistently meet the compliance with overboard discharges (6). 6a. Bal Pure: The BalPure ballast water Commercial treatments of bilge water using treatment system by Severn Trent De Nora in Fort membranes include those with synthetic and ceramic Washington, Pa., is a high-capacity treatment system membranes. Synthetic membranes with molecular cut designed to eliminate harmful species in ballast water off rating up to 100000 (Dalton) are able to capture with no adverse environmental side effects (7). The most oily particles, free or emulsified, in bilge water. BALPURE® ballast water treatment system from Ceramic membranes have been tested and used in Severn Trent De Nora received basic approval from naval ships for treatment of oily bilge water with the International Maritime Organization's Marine generally good results. The membranes are susceptible Environment Protection Committee (MEPC) 60th to irreversible membrane fouling over time. Adequate session, March 22-26, 2010.

64 Through the oxidation of the halide ions in seawater, (polyphenols). The loading should be regulated to the proprietary BalPure electrolyzer generates oxidants maintain reasonably steady throughput to optimize the that are injected into the ballast stream where they performance of the biomass. Loading upsets can react with both inorganic and organic matter, as well overwhelm and shutdown biological units. Capital as bacteria, to provide effective disinfection. As the costs tend to be high and the unit requires operators harmful organisms are inactivated or destroyed, the with high-skill levels. The economy of scale of the oxidant concentration in the ballast water is reduced. biological system seems to favor large vessels with The BalPure system then introduces a neutralizing high loadings and less space constraints. Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 agent to the ballast water where it reacts with residual oxidant rendering the water safe to discharge into Ultrafiltration membrane systems are desirable in waterways." circumstances where loading is fairly low and uniform. These requirements underline the 6b. OceanGuard Ballast Water Management importance of the pretreatment system to regulate and System (8): The system is manufactured by Qingdao lessen the overall contaminant loading to the Headway Technology Co. The system utilizes membranes. An efficient pretreatment not only reduce Advanced Oxidation Processes technology (AOP). footprint but also reduces membrane cleaning costs. Hydroxyl free radical (·OH) is produced from clean & These systems as a whole can perform well if they do filter water assisted by ultrasound and proprietary not need to operate 24/7 and the membranes cleaning electrocatalysis. Hydroxyl free radicals can oxidize can be automated to operate during down times. very quickly almost all the biological macromolecule, Membrane separation seems to provide the most organic substances or the inorganic substances. Since consistent performance guarantee to comply with the oxidation rate is extremely high, it is particularly regulations for overboard discharges. suitable for ballast water. The system has the automatic self-cleaning function to avoid the Surface modified filtration devices exhibit high accumulation of sediment of the organisms inside the performance and the highest degree of robustness in system. OceanGuardTM Ballast Water Management regard to loading and throughput. These devices will System can be used in both rivers and oceans, and is not shutdown in the condition of high loading and will completely automated. The by-products of the maintain a consistent effluent concentration and low reaction are only H2O and O2, which are very operating pressure. Initial capital costs are low, but environmental friendly. replacement filters are required, and the spent filters must be used for fuel or stored. The efficiency of DISCUSSION & CONCLUSION processing emulsified oil is not always guaranteed for stable emulsion. The bilge water treatment technology will continue to diversify as more land-based technologies are being Centrifugation / flocculation units exhibit very good adapted for the marine applications. Selecting the overall performance but the centrifuges require high optimum design for a specific application requires the degree of maintenance and initial capital outlay is background data such as throughput, solids, and free high. Flocculation units involve chemical storage and and emulsified oil loadings. Operating conditions addition. The system can be overwhelmed if such as temperature, humidity, weather patterns, and centrifuges are not working properly and there is a dustiness of the environment should be considered. sudden change in influent concentration. Certainly conventional OWS based on coalescing media is well established and is the single best The field of ballast water treatment technology technology for making the primary free oil removal. appears to be evolving rapidly. In 2009, the number of Emulsified oil can be partially converted to free oil if systems which have presented data demonstrating the feed temperature is raised as close as possible to 40oC- potential to meet California’s performance standard 50oC. has more than tripled - from two to seven. It is expect to see a great increase in the available data on system Biological units perform better on sanitary waste than performance in the near future, particularly as systems bilge water since biomass is less capable of oxidizing are installed on operational vessels beginning January some components such as grease and tars 1, 2010 for the initial implementation of California

65 performance standards for vessels with a ballast water capacity of less than 5000 MT.

ACKNOWLEDGEMENT

Special appreciation to Lou Mazzarone of Coffin World Water Systems for encouragement and Downloaded from http://asmedigitalcollection.asme.org/MTS/proceedings-pdf/MTS2010/99397/58/2520471/mts2010-0207.pdf by guest on 01 October 2021 guidance, John Boyajian and Paul Wickstrom for sharing the archive of actual bilge data.

REFERNECES

1. Alper, Hal, “Removal of Organic Pollutants and Warfare Agents Utilizing Surface Modified Filtration Devices” National Defense Industrial Association, San Diego, CA, April 2003. 2. Plebon M. J., Marc Saad, Serge Frazer, Earth Corporation, Montreal, Quebec, Canada, “Further Advances in Produced Water Deoiling…”, 12th International Petroleum Environmental Conference, Houston , TX, November 8-11. 3. RPA Liquid Sorbent, US Patent 5239040 4. Sinker, A. et. al., 2007, “less Oil In, Less Oil Out, A holistic Approach to Enhance Produced Water Treatment” 17th Produced Water Seminar, Houston, TX, January 17-19. 5. Smith A., Bentley, A. “The Optimization of Membrane Bioreactor Technologies for Use in the Treatment of Marine Wastewater”, International Conference, Bremerhaven September 12-14, 2001. 6. Nemser S.,” Fouling Resistant UF Membrane for Treatment of Oily Bilge Water”, EPA Contract # 68D02015, April 1 to Sept 1, 2002. 7. Marinlink.com, “Basic Approval, Bal Pure Ballast Water Treatment” 1996-2010 Maritime Activity Report, NY, NY, 10010, April 23, 2010. 8. Sustainable Shipping News, The OceanGuard System use AOP to gain IMO Approval, Feb 3, 2010. 9. Myers D., Surfactant Science and Technology, 3rd Edition, pp 306-311, John Wiley & Sons Publisher, 2005

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