Odorant Effectiveness

Overview

Main Objective

Gas Technology Institute's (GTI) objective of the project is to provide a "Practical Pipeline Operator Guide" to manage odor fade issues associated with typical gas system operating conditions and materials of construction. This will include a tested model and methodology to validate additional combinations of gas, system, and material scenarios as they become available in the future.

Public Abstract

Objectives: The objective of the project is to provide a "Practical Pipeline Operator Guide" to manage odor fade issues associated with typical gas system operating conditions and materials of construction. This will require identification, prioritization, and quantification of the most important variables leading to odor fade. Ultimately, the project will develop a predictive model that can be used to counter odor fade, validate this model on a subset of variables, and incorporate a methodology to enable the validation of additional combinations of gas, system, and material scenarios. Ideally, the project results, guide, and validation data will also be incorporated into the next update of the American Gas Association (AGA) Odorization Manual (after discussions with the appropriate AGA committee).

Methodology: It is important to have industry consensus on how the project results will be disseminated and the format of the eventual model construction. The first task will focus on discussions with a project steering and advisory committee, and performance of a literature search and gap analysis. Once the gaps are identified, the chemical and physical phenomena that can induce odorant fade will be defined, ranked and prioritized, based on thermodynamic prescreening, prior testing, literature, and operator experience. Design of Experiment software will be used to setup a series of static laboratory scale tests to develop a matrix of variable combinations to determine how they affect system odorant levels with time, pressure, temperature, etc. Fluid flow simulation software will be used to evaluate selected gas system piping scenarios. These software packages will be used to develop the working model that will be validated through a series of physical tests on actual pipeline segments and/or systems in the field.

Summary and Conclusions

Modeling using field data was originally intended to be accomplished through a series of physical tests on pipeline segments and/or systems which involved piggy backing on an already existing operating line at one of the stakeholder companies. However, discussions with project stakeholders suggested that there were many issues with this approach. As the project concluded, only two companies were able to supply useful field data. As a result, conclusions are limited. In the field simulations, the THT odorant loss was significantly overestimated. TBM odorant loss was also overestimated, although to a lesser extent. The information gained in this project was used to prepare a suggested revision to Chapter 7 of the AGA Odorization Manual.

Relevant Files & Links