NACE 34101

Abstract

<strong>Introduction</strong> <br>Many different types of process additives are used to maintain reliability and optimal performance of refinery operations. An additive can be a proprietary chemical such as a corrosion inhibitor, antifoulant, oxygen scavenger, or a water stream injected to dissolve salt deposits or dilute corrosive process components. Typically, these additives have been injected into refinery piping systems through small branch connections either directly or through a quill or spray nozzle. The locations at which these additives are introduced into process streams are commonly referred to as injection points. <br>Several corrosion mechanisms associated with injection points have become apparent to refinery personnel over the years. Many of these problems have resulted in highly localized deterioration. In recent years, several wellpublicized piping failures associated with injection points have been discussed at industry forums such as NACE and API⁽¹⁾meetings. Upon discussion, it has become apparent that in several cases, existing levels of attention directed at injection point problems were not adequate to identify and mitigate problems. As a result, industry organizations have sponsored work to better define good practices around design and integrity of injection systems. API has included inspection of injection points in API 570.¹ <br>Each refinery injection situation is different in the details that determine success or failure. Because of the variety and uniqueness of applications, this report is not to be used or interpreted as a compilation of recommendations, because recommendations are outside the scope of technical committee reports. There is no intent to provide detail in this report for quantitative design of an injection system. Rather, relevant issues are introduced and, when possible, considerations and practices that have been successfully used are given to aid the application of good engineering judgment on the part of the designer. <br>⁽¹⁾ American Petroleum Institute (API), 1220 L St. NW, Washington, DC 20005.