2021 IIAR Technical Papers
Virtual Conference
43rd Annual Meeting

CFD Analysis of Pipework Fracture due to Hydraulic Shock in an Ammonia Refrigeration System
Chidambaram Narayanan, Principal Engineer
AFRY Switzerland AG

Bent Wiencke, Consultant
Chill-On LLC

Lane Loyko, Consultant
PLA Corp.

The condensation induced hydraulic shock (CIHS) phenomena is a primary safety concern in low temperature ammonia systems. When transient pressure amplitudes become exceedingly high, pipe rupture can occur. Of particular interest to the ammonia industry is the development of a computational fluid dynamics (CFD) modeling tool that can accurately predict scenarios which can lead to pipe rupture due to formation of a hydraulic shock.
RAGAGEP: Historical Variants and the Importance of IIAR Standards
Uriah Donaldson
Process Safety Consultant, Resource Compliance

This paper will discuss the importance of adhering to the International Institute of Ammonia Refrigeration (IIAR) suite of standards by exploring variants in historical RAGAGEPs related to ammonia refrigeration. The goal is to provide individuals who are responsible for PSM/RMP programs with an understanding of the ammonia industry’s historic RAGAGEP requirements in order to aid them in documenting that their systems have been designed in accordance with recognized and generally accepted good engineering practices at the time of construction.
Identifying and Quantifying Fugitive Emissions from Industrial Refrigeration Systems
Marc Claas

Research Engineer

Douglas Reindl, PhD, PE

Todd Jekel, PhD, PE
Assistant Director;

John Davis, PE
Associate Researcher

Jacob Grayless
Research Intern

This paper discusses methods for finding and quantifying fugitive emissions of ammonia from industrial refrigeration systems with the goal of reducing refrigerant losses that occur from these systems. From the outset, the working hypothesis is that fugitive emissions represent a significant contribution to the overall refrigerant loss rate for industrial refrigeration systems. Since there has not been an organized effort to
identify and quantify fugitive emissions associated with industrial ammonia refrigeration systems, this hypothesis needed to be tested as a prerequisite to establishing approaches to reduce refrigerant losses.

Risk-Based Inspection for the Ammonia Refrigeration Industry
Richard (Ric) Hartung
Sr. Engineer/Consultant, Process & Safety Solutions LLC

The OSHA Process Safety Management (PSM) program and the EPA Risk Management Plan (RMP) rule rely on mechanical integrity to achieve the desired results. In the case of piping and equipment exposed to anhydrous ammonia, the predominate damage mechanism is external corrosion or corrosion under insulation (CUI). Facilities that operate an ammonia refrigeration process must conduct inspections of piping and vessels at least annually. Should any piping or vessel surfaces indicate pitting or metal loss, further examination by non-destructive testing (NDT) is required
The Case for HAZOP – Minimizing Effort and Increasing Longevity
Stephanie Smith, PE

Senior Engineer, Risk Management Professionals

Should the hazard and operability (HAZOP) methodology be considered the industry standard for hazard reviews (HRs) and process hazard analyses (PHAs)? The topic is currently the focus of a vigorous debate in the industrial refrigeration industry. While there are advocates for and against employing HAZOP methodology, this paper will argue that the benefits generally outweigh the costs.
Designing Industrial Refrigeration Systems for Full Vacuum – Considerations
Martin L. Timm, P.E., CSP

Managing Member, Centigrade Services LLC
Considerations around modes of test and operation that place ammonia refrigeration systems in a vacuum are discussed. A literature review of IIAR publications and general industry recommendations regarding design of pressure vessels and systems for evacuation and operation is presented. Results are presented for ASME B&PVC calculations for a range of typical pressure vessels constructed from A516 carbon steel showing that full vacuum should not be applied to vessels that exceed a specified length to diameter ratio (L/D), unless the vessel nameplate indicates it has been designed for full vacuum.
Sustainable Use Cases for Ammonia as a Refrigerant in Residential/Light-Commercial HVAC

Vikas Patnaik, PhD, MBA
Vice President of Product Development, Modern Electron

Michael Garrabrant
President, Stone Mountain Technologies, Inc.

A significant amount of research and development has gone into the deployment of ammonia as a refrigerant in air conditioning and heat pump systems, going back to the first half of the twentieth century. This presentation provides an overview of the basic thermodynamic cycles currently in application/development/consideration, the accompanying hardware systems in various stages of maturation, and the pros and cons of using this earliest of refrigerants that continues to provide some of the most promising performance – both in terms of all-around environmental impact and energy (resource) consumption. 

2021 Programa en español

Análisis de ciclos de refrigeración por amoniaco
Silvio Toro Toro, Master en Ingeniería de Refrigeración
General Tech. Manager, Froztec International Inc.

Descripción y análisis de los ciclos aplicables de refrigeración con amoniaco de vapor por compresión como información básica para diseños de sistemas de refrigeración orientados a aplicaciones industriales, con diferentes rangos de temperatura, incluyendo; procesos de ultra baja temperatura, baja temperatura, temperatura media y alta temperatura para cubrir todas las necesidades industriales ajustándose a las necesidades de los proyectos desde procesos de congelación, refrigeración, hasta acondicionamiento de aire en fábricas de procesos que requieran de instalaciones frigoríficas.

Estos análisis so teniendo en cuenta compresión adiabática y por tanto no se tiene en cuenta el tipo
de compresor o enfriamiento de los mismos, es basado estrictamente en el diagrama de Mollier
Evaporadores para Áreas de Procesamiento de Alimentos
Bruce I. Nelson, P.E.
Presidente, Colmac Coil Manufacturing

El control de patógenos en instalaciones de procesamiento de alimentos juega una parte importante en garantizar la seguridad de nuestros suministros de alimentos. Entre otros requerimientos, la USDA exige que el equipo sea limpiado cuidadosamente para remover manchas y después sanitizado para desinfectar las superficies. Con frecuencia estos dos procesos involucran químicos, los cuales, si no son seleccionados y aplicados adecuadamente, tienen el potencial de corroer y dañar las superficies de metal de los evaporadores.
Válvulas Motorizadas, como sacar el máximo provech
Roberto Badillo Chávez
Ingeniero en Alimentos, Danfoss México

Partiendo de las crecientes necesidades de mejorar la eficiencia de los sistemas de enfriamiento, de reducir los costos de producción, de los avances en la tecnología de los equipos de refrigeración, así como del cada vez mayor interés y necesidad de reducir el impacto ambiental sin dejar de lado las cada vez más complejas necesidades de distribución de alimentos manteniendo la cadena de frío y las mayores exigencias de los consumidores en la calidad de los alimentos, las válvulas y controles de un sistema de enfriamiento han evolucionado a fin de atender las crecientes necesidades y mayores exigencias de la industria del frío.
Procedimiento LOTO para Sistemas de Refrigeración
Juan Carlos Zeledón, Maestro en Ingenieria Sanitaria, Ingeniero Industrial,
Líder de Seguridad de Procesos, Cargill de Nicaragua, S.A

Las energías peligrosas son la causa raíz de muchos accidentes laborales incapacitantes, fatales y accidentes de relacionados a la seguridad de los procesos, este documento contiene información para controlar dichas energías través del Procedimiento de Bloqueo y Etiquetado (LOTO, por sus siglas en ingles de Lockout-Tagout) para evitar estos eventos.