1999 IIAR Technical Papers
  Dallas, TX
 21st Annual Meeting

Installation of Natural Gas Engine Driven Ammonia Compressors for Energy Savings
Author: Joe Bukowski

This paper will detail the actions taken to install two 800 hp natural gas engine drive ammonia screw compressors at the Miller Brewing Company brewery in Irwindale, California. The installation is a retrofit of an existing machine room that contained nine 700 hp electric drive screw compressors. The original installation was performed in 1978. Two of those compressors were dedicated to a 45-psig suction system and the remainder were installed on a 25-psig suction system, with one compressor able to swing to either suction level. The gas engines were equipped with California pollution control packages and were equipped with heat recovery to heat water used in the process. Natural gas has become an attractive alternate fuel for areas of the country where high electric demand charges are encountered. A brewery is a very energy-intensive facility with cooling required for incoming water, beer under fermentation, aging and finally, for packaging. Space cooling and dehumidification requirements are also quite large. Southern California can have peak power charges of fifteen times the normal power charges during summer daytime peak periods.
Ammonia Absorption Refrigeration Unit Provides Environmentally-Friendly Profits for an Oil Refinery
Author: Donald C. Erickson

A waste heat-powered ammonia Absorption Refrigeration Unit (ARU) has completed the first year of operation at the Denver refinery of Ultramar Diamond Shamrock. The ARU provides 85 tons of refrigeration at -25°F to refrigerate reformer plant net gas and treat gas, thereby recovering 50,000 barrels per year of liquefied petroleum gas (LPG) which formerly was flared or burned as fuel. The ARU is powered by 290°F waste heat from the reform reactor effluent. An additional 180 tons of refrigeration is available to de-bottleneck the Fluid Catalytic Cracker (FCC) plant by cooling the inlet vapor of the wet gas compressors. The ARU is directly integrated into the refinery processes, and uses enhanced, highly compact heat and mass exchangers. The refinery’s investment will pay back in less than two years from increased recovery of salable product, and C02 emissions are decreased by 10,000 tons per year in the Denver area. This project has been designated “Environmental Project of the Year” by the Association of Energy Engineers.
Vibration Problems and Solutions for Industrial Refrigeration Screw Compressors
Author: Randy Keefer

Rotating gas compression equipment has developed a reputation for being a generator of objectionable noise and vibrations. While this can be the “nature of the beast,” the technology exists to discover the exact cause of vibration and to “tame the beast” by providing design and field modification solutions. This presentation will discuss types of vibration related problems, particularly those related to helical screw compressors, and present techniques and procedures that will improve equipment life and can reduce or eliminate objectionable levels of noise and vibration.
New Developments in Automatic Freezing Technology in Australia
Author: Klaas Visser

Since 1979 we have successfully developed automatic large scale plate freezers in Australia with individual capacities up to 70 tonnes (154,350 lbs) per day when freezing 2,600 of 27.2 kg (60 lbs) cartons of meat. Plate freezing offers many advantages over conventional air blast freezing, such as sharply reduced energy consumption, fast freezing times, improved cold storage and container utilization, and reduced freight costs due to reduced fuel costs for road, rail and sea transport. The reduced fuel costs are, in turn, due to a reduced number of containers necessary to transport meat and the capability to chill hot boned meat and offal products quickly to 7°C (44.4F) in the centre of a carton. This prevents growth of pathogens such as salmonella and E. Coli, which are injurious to human health.
Thermosyphon Chilling Using Ammonia as the Refrigerant
Author: David Blackhurst

The development of the thermosyphon cooling system for use with ammonia is a significant and timely one. It continues to prove itself a highly efficient, reliable and cost effective system. With growing concerns over global warming, it provides those with suitable processes with a means of significantly reducing the environmental impact of their operations while saving money. The perceived dangers associated with the use of ammonia can be engineered out. The growing acceptability of ammonia as the refrigerant of first choice, particularly in the Building Services environment, is to be welcomed and encouraged. The onus of maintaining and developing the good safety record of ammonia systems lies with refrigeration practitioners.
The Single Screw Compressor
Author: Wayne Wehber and David Anderson

Single screw compressors have many design attributes, which make them ideal for a wide range of compressor applications. These attributes include a high degree of reliability and efficiency, demonstrated versatility and the ability to operate at high differential and discharge pressures. The geometry of the main screw results in balanced radial and axial forces and therefore low bearing loads. The gate rotors are independent assemblies within the housing which also operate with minimum bearing loads and maximum design flexibility. This allows the bearing systems to be designed for maximum reliability. The Parallex Slide System(TM) allows maximum operational flexibility while delivering optimum performance. Capacity control can range from 10% to 100% of full flow with compression ratios greater than 20:1. The dual slide arrangement also allows the compressor to start at 10% capacity at a volume ratio of one and operate efficiently at part load conditions. The single screw compressor has a proven history of economical and reliable service in the air compression, air conditioning, and refrigeration industries. Additionally, it is currently providing the same level of quality service for petrochemical and industrial process applications.
Ammonia Line Sizing by Spreadsheet
Author: Nigel Andrews and Jeff Welch

Many engineers in our industry use the ASHRAE RP-185 line sizing publication on a daily basis. This document is an excellent engineering tool, which Mr. D. D. Wile presented in an extremely useful format. Unfortunately, ASHRAE has decided not to reprint this publication. They have, however, expressed a willingness to offer the artwork to IIAR for publication and this may happen at some point in the future. At the present time, copies of RP-185 are not readily available. The IIAR Piping Committee has developed tables of recommended line sizes for the new IIAR Piping Practices Handbook, in lieu of the more conventional tables based on mass flow.
The Importance of Following Ammonia Refrigeration Piping Guidelines
Author:  Dipti Roy

All of us in the IIAR realize that there are a number of different philosophies or "schools of thought" that are used in the design of systems. Some examples are liquid injection vs. thermosyphon oil cooling, liquid recirculation vs. control pressure receiver feed, mechanical pumps vs. gas pumping systems, etc. These differing philosophies are good for the ammonia refrigeration industry. They sometimes cause members to polarize themselves with others who share their beliefs, but claims made by the opposition help them to seek out the truth, even if it is only for purposes of discrediting the opposition. There are instances, however, where these divergent philosophies of design are not healthy. Our facility in the southern U.S. was influenced by several schools of thought in the field of refrigeration. Any one of these philosophies, on its own, would have worked well, but a plant created piecemeal by several different "authors" became a "Frankenstein" monster. The situation was as if one had 1/5 of their house painted each year, each time by a different painter, using a different type of paint, and employing a different color scheme.
Integration of PSM/RMP Into a Typical Business
Author: Don Jeter, P.E. and Ed Eliason

The Clean Air Act Reauthorization created a new environment for industry. In addition to consideration of the day to day releases of hazardous materials, it also mandated a focus on catastrophic releases, in particular, their prevention and mitigation. The mandates of the Clean Air Act Reauthorization are addressed by the OSHA’s Process Safety Management Program (PSM), and the EPA’s Risk Management Program (RMP). The PSM program focuses on the safety of the workers at an industrial site, while the RMP focuses on the offsite safety issues. Both of these programs (PSM & RMP) require industry to take a proactive approach to the prevention and mitigation of catastrophic releases. In particular, the PSM program and RMP-prevention program involve fourteen elements. These elements are more effect-oriented than prescriptive, leaving the details for implementation and integration up to the owner/manager of the facility. Some of the elements require the facility owner to timely address recommendations for changes, while others require planning and training for adverse situations. This paper looks at the integration of these elements with respect to a typical business.
Ammonia Flaring Systems
Author: James J. Shepherd

Flaring is an oxidation process at high temperatures for the disposal of toxic or waste gases during normal maintenance or emergencies. Flares, or oxidizers, are employed for the quick release of a relief valve or other emergencies that create the need to discharge a large amount of toxic or flammable vapor. This process can prevent ammonia vapor from entering an undesired area or causing a high-pressure condition that might create a failure of a vessel or other component in the system. By oxidizing the vapors, the gas is reduced to non-toxic C02 and water, with minimal secondary pollutants.
Compressor Hall Project
Author: Boshra B. Shehata

This paper describes a new ammonia refrigeration plant, referred to as “Compressor Hall,” that replaced an old ammonia refrigeration plant. The ammonia refrigeration system in the Compressor Hall supports the operations of the oldest and largest brewery owned by Anheuser Busch Companies. It is one of the largest breweries in the world, with an annual brewing capacity of 14 million barrels of beer per year (16.4 million hectoliters). This brewery is located on a 100-acre site in St. Louis, Missouri, USA.
Virtual Refrigeration Simulator: A New Way to Train Refrigeration System Operators
Author: John Hench, Steve Griffin, and Bob Norcross

The Virtual Refrigeration Simulator (VRS) is a PC-based tool created under the sponsorship of RETA to train and evaluate refrigeration system operators. The VRS has the ability to simulate the failure of various components of a refrigeration system using animated color graphics. It allows the operator to measure different operating and physical parameters to determine the cause of the failure and return the system to normal conditions. The VRS keeps track of the time it takes each operator to resolve each failure and presents results in the form of a report.
Ammonia Refrigeration in Sanitary and Aseptic Applications
Author: Martin Timm, P.E.

Cooling is an important unit operation in many sanitary and aseptic processing applications. Industries that must process in a sanitary or aseptic fashion include food, beverage, brewing, dairy, personal care products, pharmaceuticals, etc. Ammonia refrigeration is an integral part of the cooling systems used in many applications in these industries. It is used both in direct and indirect cooling applications. The special requirements of sanitary and aseptic applications have led to special construction, installation, operation, and cleaning practices. This paper describes the special needs of sanitary and aseptic fluid cooling applications, and the equipment that has evolved to serve these applications.
Application of Ice Slurry/TES Technology to Supermarkets Using Ammonia Refrigeration
Author: David Leuders

By using the Ice Slurry TES System in a Supermarket Application, we can achieve the following benefits to the Owner: 1. By switching to a secondary refrigerant (Ice Slurry) we eliminate approximately 75 % of the refrigerant inside the Store. All the WAC loads, High and Medium Temperature Display cases will utilize the Ice Slurry or Chilled Glycol as the Cooling Medium. The only Refrigerant required inside the Store would be in the Low Temperature Display Cases. 2. By using Ammonia as the primary Refrigerant we accomplish converting to an Environmentally friendly Refigerant. 3. In Electricity use, we are able to achieve a 49 % reduction in operating Costs. 4. In overall Financial terms we are able to obtain a 22 % reduction in Cost of Ownership or 10 Year Lifecycle Cost. This translates into net savings of $216,500 over a 10 year period. 
State-of-the-Art Energy Efficiency in Refrigerated Warehouses
Author: Marcus H. Wilcox, P.E.

This paper presents current state-of-the-art energy efficiency technologies for refrigerated warehouses. These technologies are applicable to a wide range of facilities, including distribution centers, controlled atmosphere, freezer warehouses, and cooler warehouses. First, a general summary of opportunities will be presented. Then, some of the more unique, emerging, or even controversial opportunities will be discussed in detail. Finally, several case studies will show what levels of savings and final economics are possible.
Oil in Ammonia Refrigeration Plants
Author: Kurt Hytting

There has been an increasing concern about the deteriorating performance of “standard” refrigeration mineral oils, particularly in ammonia plants. Considerable investigation has revealed a number of very real problems, which are detrimental to the refrigerating plant and equipment. A number of procedures have been developed to help contractors and users identify the problems and then rectify them. At least one major compressor manufacturer has found it necessary to develop their “own brand” of lubricating oils to secure the quality that is necessary for modern refrigerating plants. It has been identified that many plant operators and service agents do not properly monitor and maintain their refrigerating systems or equipment. The information presented in this paper is designed to inform owners, operators and service agents about the problems that have been seen - and some of the possible solutions. Many of them are self evident, yet they are seldom implemented. The recommendations made in this paper are designed to achieve precisely this result.