Abstracts of Technical Papers by Kirby Mohr

Mohr, K. S.; A NEW TYPE OF HIGH EFFICIENCY OIL-WATER SEPARATOR FOR BETTER WATER QUALITY MANAGEMENT, Pacific Northwest Pollution Control Association Meeting; Boise, Idaho, 1992.

Abstract:

Environmental regulation of oil in water discharges is becoming increasingly more stringent. Many localities now require oil content of water discharges to be limited to less than 10 mg/l. Various types of systems are available to remove oil from waste or storm water streams. The systems available are discussed, including benefits and disadvantages of each.

The design and advantages of a new high efficiency oil-water separator system utilizing multiple-angle coalescing plates are described.

Overall oil-water separator system design is discussed and recommendations for ensuring system efficiency, regulatory compliance, reliability, and effective operations are presented.

Mohr, K. S.: STORMWATER TREAMENT FOR CONTAMINANT REMOVAL, Public Works and the Human Environment: Proceedings of the International Symposium on Humanity and the Environment; Seattle, Washington, 1995.

Abstract:

Included in the paper are discussions of contaminants expected to be present in stormwater runoff, the expected concentrations of these contaminants, estimation methods for determining the amount of runoff water to be processed, and methods used to treat the water for contaminant removal. Information is presented on both domestic and international treatment methods. Emphasis is placed on hydrocarbons in the stormwater and removal of these hydrocarbons to acceptable levels. A discussion is also provided concerning legal considerations in treating stormwater

Mohr, K. S.; PROBLEMS WITH URBAN STORMWATER - CONTRIBUTIONS OF CONTAMINANTS TO THE ENVIRONMENT, Proceedings of the Florida Environmental Exposition; Tampa, Florida, 1996.

Abstract:

The intent of the paper is to provide a review of contaminants noted in urban stormwater which can enter streams and lakes, some of their toxic effects, and management practices. Particular emphasis is placed on hydrocarbon and heavy metal contaminants. A discussion is provided with information on the type and concentration of contaminants that may be expected. Though the paper is intended to be primarily technical in nature, references will are made to regulatory issues as well as to current and possible management practices.

LaRusic, A.; Mohr, K. S. DESIGN AND INSTALLATION OF A HYDROCARBON REMOVAL SEPARATOR FOR INDUSTRIAL STORM RUNOFF, British Columbia Water and Waste Association; 1998.

Abstract:

A new storm water collection and treatment system was installed at a major Vancouver Harbor port in 1997 to process surface runoff. The case illustrates many of the complicating factors which need be considered in the design of a storm water treatment system incorporating a high efficiency oil/water separator.  New construction at the port necessitated the removal of the old oil/water  separator, which was not operating optimally. The new system included a redesigned storm water collection system and a new oil/water separator utilizing multiple angle coalescing plates for high efficiency removal of oil in the water. Factors considered in the new design included high concentrations of various solids, oil-water emulsification due to detergents from a high-pressure equipment wash facility, and sewer flood conditions resulting from the proximity of tidally-influenced waters.  A study of the influent streams to the separator indicated that many streams had a low likelihood of containing oil concentrations that would exceed permitted limits, and these were routed to bypass the separator, reducing the separator size and cost. A small, low-maintenance wastewater treatment facility that recycled wash water was installed at the most problematic source, the high-pressure wash facility. A grit chamber was installed directly upstream of the separator to remove the majority of solids before separator treatment. A check valve was installed to prevent the backflow of tidal waters into the separator.  The new separator was specified with multiple-angle coalescing plates for maximum separation of oil droplets and solids. A process simulation was performed based the water quality of the input streams and the application of Stokes Law to a statistical range of oil droplet sizes in order to predict oil concentrations from the separator effluent stream. The new storm water treatment system has proven to provide an effluent quality superior to that required by the regulations, with minimal maintenance efforts.

Mohr, K. S.; EFFECTIVE PRETREATMENT FOR HYDROCARBON / VOC REMOVAL, WEF Industrial Wastes Technical Conference; Nashville, Tennessee, 1998.

Abstract:

Pretreatment of industrial wastewater to remove hydrocarbons is often required so that the hydrocarbons will not cause VOC emissions from Publicly Owned Treatment Plants (POTWs) to exceed regulatory limits. A discussion of hydrocarbons in wastewater and several methods of pretreatment are included as well as examples of pretreatment systems and recommended criteria for choosing a pretreatment system.

Mohr, K. S., AN OVERVIEW OF US AND INTERNATIONAL REGULATIONS REGARDING HYDROCARBONS IN WATER EFFLUENTS, WEF Industrial Wastes Technical Conference: St. Louis, Missouri, 2000.

Abstract:

The amount of hydrocarbons allowed in industrial and Stormwater effluents varies greatly from one locality to another or from one country to another. Some countries mandate hardware solutions to the effluent problem and others stipulate a specific concentration allowable.

The paper presents the regulations governing effluents in many countries and states and localities within the US as well as offering discussions of some of the hardware systems required by various jurisdictions.

Burns, D. L., Mohr, K. S., COOLANT WASTE MINIMIZATION USING A COALESCING PLATE SEPARATOR, WEF Industrial Wastes Technical Conference: St. Louis, Missouri, 2000.

Abstract:

During 1998 a project was initiated at Wolverine Tube in Shawnee, Oklahoma to increase machine tool coolant life and also to increase the life of the tooling used to manufacture copper tubing from copper billets.

The coolant was becoming contaminated with tramp oil that provided a substrate for bacterial growth and tended to upset the operations of the tube reducer machine. The tramp oil also caused undue wear on the tooling and reduced tooling life.

An initial test was conducted using a small, relatively low flow rate coalescing plate separator. This test was very successful, but the flow rate from the test separator was not adequate for the requirements of the tube reducing operations. A larger separator was subsequently constructed and installed. The separator has been in service more than a year.

The paper presents the results of the initial testing as well as the longer-term reduction in waste coolant production and tooling/operating cost reduction. Coolant waste is reduced to approximately 1/3 of previous quantities and costs are substantially reduced. The tramp oil removed by the separator is being recycled as well, and information on this recycling is presented.

Gutierrez, J. M., Mamuscai, D., Mohr, K. S., UPGRADING PETROLEUM TERMINAL SEPARATORS USING COALESCING PLATES, WEF Industrial Wastes Technical Conference: St. Louis, Missouri, 2000.

Abstract:

In 1999, a project was instituted to replace two oil-water separators at Mobil de Colombia's terminal facilities in Cartagena, Colombia to bring the facility into compliance with environmental law.

The separators are concrete in-ground pits equipped with rudimentary baffles and skimmers as well as built-in tanks for accumulation of separated oil. They process water from equipment washing as well as from rainwater runoff. Inlet to the separators is by gravity flow sewers.

It was suggested that it might be possible to inexpensively upgrade the performance of the existing separators using multiple-angle coalescing plates instead of providing above-ground steel separators. This would also avoid the additional cost of pumps and utilities to pump the oily water into the proposed new separators.

The existing pit separators were evaluated using a proprietary computer program and it was determined that the existing pits were large enough to meet the national environmental regulations for effluent oil content if fitted with multiple-angle coalescing plates.

The paper presents information on legal requirements, a discussion of how the operating conditions were determined, the new internals designed, and a discussion of how the new internals will affect the quality of the water exiting the facility.

Foley, M., Veenstra, J. N.; Mohr, K. S., UPGRADING A REFINERY "ONCE-THROUGH" COOLING WATER SYSTEM FOR POLLUTION PREVENTION, International Petroleum Environment Conference; Houston, Texas, 1999.

Abstract:

Many refineries utilize "once-through" cooling systems using river or lake water as the fluid for cooling process streams. This is an efficient means of cooling but can be a water contamination source if any of the heat exchangers leak. A "once-through" system at a refinery was studied to explore the possibility of upgrading equipment to ensure the capture of any oil in the refinery effluent in the event of a leak in a heat exchanger.

A refinery has many products that could leak into the cooling water and the magnitude of potential leaks varies widely. The water temperature varies also with weather conditions.

A design utilizing more efficient multiple-angle coalescing plate internals for the pits would be expected to reduce the impact of releases and further improve effluent water quality. Wide variations in possible water oil content, temperature, and oil specific gravity made design of an efficient system difficult. For this reason a statistical approach was taken in the design.

The paper provides information on a current refinery situation, variations in the flow, oil content, etc. as well as the methods used to estimate the probabilities of meeting effluent requirements under spill conditions with various quantities of coalescing plate media.

Veenstra, J. N.; Mohr, K. S.; Sanders, D. A. REFINERY WASTEWATER MANAGEMENT USING MULTIPLE-ANGLE OIL WATER SEPARATORS. International Petroleum Environment Conference; Albuquerque, New Mexico, 1998.

Abstract:

An overview of oil-water separation as used in the petroleum refining industries is presented along with case studies. Discussions include impact of solids, legal aspects, and differing types of systems currently in use along with advantages and disadvantages. Performance information on separators is presented with emphasis on new multiple-angle coalescing plate technology for refinery wastewater management.

Several studies are presented including a large (20,000 US gpm flow rate) system recently installed at a major US refinery. The separator was constructed by converting two existing API separators into four separators and adding multiple-angle coalescing plates to increase throughput and efficiency. A year of operating experience with this system indicates good performance and few problems. Other examples provide information on separators installed in the United States and other countries.

Vazquez, C.; Alfonsin, G.; Mohr, K.; A NEW HIGH EFFICIENCY AUTOMATIC CAR WASH RECYCLING SYSTEM, WEF Industrial Wastes Technical Conference: Indianapolis, Indiana, 1999.

Abstract:

A new system has been developed in Spain for recycling of water from automatic car washing systems. The recycled water is of very good quality and very suitable for reuse. Detergent use is reduced as well.

The system combines gross physical separation of the oil and solid particles using a plate separator system, fine separation of solids with an automatic filter system, and ozone treatment for disinfection and odor control. Other systems recycle water, but do not remove oil and solids as well.

Over 150 systems have been installed. The initial test system has washed over 6000 cars and is operating at about 75% water recycle (most of the non-recycled water leaves the carwash as a water film on the cars) and about 70% reduction in detergent use.

Mohr, K. S.; Meadows, R. E. CROSSFLOW MICROFILTRATION OF ETYHLENE GLYCOL, Proceedings, Laurence Reid Gas Conditioning Conference. Norman, Oklahoma, 1987

Abstract:

The paper presents information on a system designed to remove extremely small particles from triethylene glycol in a gas processing plant. The glycol was highly contaminated with approximately 3% solids content. The filtration system included a 0.2 micron crossflow microfiltration module that successfully filtered the glycol for recovery and removed the particles as a slurry that could be disposed.

Mohr, K. S., TRENDS IN FILTRATION OF FUELS AT SERVICE STATIONS, Proceedings American Filtration Society Annual Meeting, Chicago, Illinois, 1992

Abstract:

Filtration of gasoline at service stations is becoming increasingly more important due to the extensive use of fuel injection systems for automobile engines. Customers now demand the finest quality fuels, free from both water and solid impurities.

Systems to remove these impurities are in various stages of development. Spin-on type filters have been used for many years and other types of filtration systems are now being introduced.