RIASSUNTO
Abstract
Acrolein (2-propenal) is a highly effective microbiocide and sulfide scavenger that has been commercially available since 1960 and has been widely used in the oil and gas production industry. Acrolein is a liquid product supplied in and applied from specialized containers, eliminating potential releases from transfers between tanks. The acrolein containers are built to comply with international transportation regulations. This paper will cover the development of a safety management program and standardization of application equipment that allow the usage of acrolein for applications with a risk comparable to, or in some cases lower than, conventional chemical products.
Standardized operating procedures, closed-system application equipment (verified by industrial hygiene monitoring), and redundant safety devices are built into the system to prevent chemical exposures or misapplications. Applications are performed by trained and certified personnel who have completed a specific competency evaluation under field conditions. A detailed and customized safety management program is completed and implemented for each application with extensive client participation.
This paper will cover the core of the safety management program, which focuses on developing site-specific elements including process safety information, process hazard analysis, operating procedures, employee and contractor training, applicator competency and field evaluation, pre-startup safety reviews, management of change, and emergency planning and response procedures. A safety audit program is also implemented to ensure the completed safety management program complies with each element. Audits are conducted at the actual location during the course of the chemical application.
A strong safety management program and standardized application system have proven to reduce personnel and environmental risks by lowering the potential for misapplications or equipment failures. These systems have allowed successful treatment programs on numerous global production assets. To validate this, a series of case histories will be presented that highlight the best practices that enable the safe application of acrolein.
Introduction
Acrolein usage in oilfield applications. Acrolein has been used in numerous oilfield applications since the 1960s to treat problems associated with bacterial activity and sulfides generation. It has been used as an effective microbiocide to mitigate bacterial activity, which can cause corrosion leading to equipment failure, solids generation leading to equipment fouling, and impaired oil/water separation (Johnson et al. 1999; Penkala et al. 2004; Penkala et al. 2005; Penkala et al. 2008). Corrosion failures can potentially lead to serious environmental exposure and also possible operations personnel injury; acrolein has demonstrated the ability to provide broad spectrum system treatment and mitigate potential losses resulting from bacterial corrosion.
In addition to its demonstrated efficacy for treatment of oilfield bacteria, acrolein readily and irreversibly reacts with sulfides, both dissolved hydrogen sulfide (H2S) and iron sulfides (FexSy), to form water-soluble products (Smith 1962; Kissel et al. 1983; Howell and Ward 1991; Salma 2000; Ramachandran et al. 2008). H2S is a toxic acid gas ("sour gas??) that is present in many oilfield production systems both as a naturally occurring constituent from the producing reservoir, and as a metabolite of bacterial activity. Removal of H2S by scavenging with acrolein not only aids in achieving pipeline specification production but also mitigates significant threat to personnel working in and around potential sources of H2S release. H2S reacts with iron to form FexSy, which can cause problems associated with equipment plugging and create areas susceptible to under deposit corrosion where the FexSy deposits form. Acrolein treatment can prevent or remove these FexSy solids, thus minimizing their potential impact.