Fugitive emission services

The identification of the potential fugitive emissions consists in a detailed analysis of technical documentation of the plant (P&IDs, Process Flow Diagrams, Block Flow Diagrams, etc.) in order to recognize the main process units, relevant process lines and equipment and fluid streams.

Plant components considered as potential sources of fugitive emissions are valves, connectors (flanges, fittings), pumps/compressors seals, open-ended lines, instruments, storages, vented sources. The identification is carried out as a desk study analysis in accordance with main international standard for fugitive emissions estimation for example US EPA “Protocol for Equipment Leak Emission Estimates” EPA-453/R-95-017.

In this phase we can support understanding the kind of fugitive emissions present in the plant and to realize a functional planning according to the clients' needs to identify and monitoring the fugitive emissions. We are also able to develop a customized database including the potential fugitive emissions sources identified through the desk analysis of the plant technical documentation.

In general, for each potential source, the following features are reported in the database:

• - location (Identification, Plant, Process, P&ID, Process Unit etc.)
• - source characterization (Source type, Tag, dimensions, Stream type, Stream phase, Stream code, etc.)
• - source operation (Operating time, bypass status, etc.).be noted that to fugitive emissions have often to be added the vented emissions gas of the processes (tank vents, gas releases form pneumatic valve.

The database can also be enriched in a second phase by the results of the monitoring campaign and the cataloging and insertion of photos of the sources. The database can be elaborated to be updated periodically by entering the results of the subsequent annual Measurement Campaigns, that corresponds to the adoption of an LDAR (Leak Detection and Repair) program.

We can support industrial plant operators, specifically oil / gas plants, gas compression plants, pressure reduction plants, platforms, etc., in identifying a methodology for estimating fugitive emissions, starting from the guidelines and methodologies existing at international level.

The main standards in the fugitive emissions sector are:

• - Norma Uni 15446
• - Method 21 - Volatile Organic Compound Leaks
• - EPA-453/R-95-017 Protocol for Equipment Leak Emission Estimates which described the US-EPA Average Emission Factor Approach, Screening Ranges Approach - “leak/no leak approach” and EPA Correlation Approach, Unit-Specific Correlation Approach
• - API - Compendium of Greenhouse Gas Emissions Estimation Methodologies for the Oil and Natural Gas Industry
• - Climate and Clean Air Coalition (CCAC)
• - EPA-305-D-07-001 - Leak Detection and Repair, Best Practices Guide

We can identify the better methodology to implement in the plant, considering between desk study estimation (US-EPA Average Emission Factor Approach for example), monitoring campaign estimation (leak/no leak approach or CCAC) or both to support client’s needs.

These methodologies are internationally recognized and constitute the calculation basis for the estimation of fugitive emissions in the monitoring programs (LDAR). According to our experience on fugitive estimation, a customized methodology for a specific plant or facilities can be developed in order to meet the clients need and to support the client in the definition of an adequate approach to monitoring and reduce the fugitive emissions.

A “leak” is detected whenever the measured concentration (“screening range”) exceeds a certain threshold (i.e. “leak definition”) set forth by an applicable regulation, or performance standard, or monitoring program. Leak definition may vary by regulation, component type (e.g. valve, pump seal, etc.), process stream (e.g.: gas/vapor, light oil, etc.) and monitoring interval.

Prior to the beginning of the monitoring campaign in order to uniquely identify each source, the identification on site, by means of appropriate metallic or plastic label (“Component Tag”) reporting a unique identification code, is essential. The measurements are carried out by putting the probe at the surface of the component interface where leakage could occur.

Fugitive emissions measurement campaigns are performed through the employment of one or more of the following tools, directly owned or in use by our team:

• - Multi Gas Analyzers: model RKI Eagle 2, provided with three sensors: catalytic for CH4, infrared for CO2 and photoionization for VOCs. The same analyzers can be equipped, upon Client and project needs, with electrochemical sensors for H2S
• - PhotoIonization Detectors (PID): model MinRAE Lite, provided with a 10.6 eV lamp
• - Infrared Camera for Optical Gas Imaging of Vocs: model FLIR GF 320, provided with a cooled Indium Antimonide detector
• - Flame Ionization Detector (FID)

Each of the above tools is periodically and at least before and at the end of each campaign, calibrated by an official and accredited dealer. Calibration certificates are provided to the client along with project deliverables. In particular the infrared camera can allow for monitoring of a large number of potential sources by identifying the “leaking” components, while the other gas analyzer above described can measure the screening values of the leakage, which can be used to implement the desk estimation.

The fugitive emissions monitoring campaigns can be implemented:

• - for supporting and complementing desk engineering estimation of facility fugitive emissions
• - within the framework of a LDAR program
• - setting the priorities for the maintenance activities.

The estimation and campaigns results are analyzed in a critical way by our experts in fugitive estimation. We are provided with up-to-date field investigations equipment and a wide software library, that combines industry standard tools and computer graphics programs for site date visualization, processing and statistical analysis.

We can provide clients with the analytical analysis of the results, querying the database functionally on the aspects to be investigated (year of construction of the plant where the greatest losses were found, which equipment are subject to the greatest losses, levels of emission reduction after maintenance).

Given the impact of methane emissions on climate change, we can help the Oil&Gas Companies in the management of these emissions, in order to agree the details about the improvement of a dedicated maintenance schedule (as LDAR program) and the establishment of reasonable emissions reduction targets.

A LDAR (Leak Detection and Repair) program is the system of procedures used to identify and repair leaking components, in order to minimise methane emissions and it includes normally:

• - scheduling or systematic inspections
• - producing and tracking work orders when leaking components are discovered
• - training of personnel, who should be aware of the importance of emissions reduction
• - procedures for identifying leaking equipment, procedures for repairing and keeping track of leaking equipment
• - methods of verification which ensure that the LDAR program is correctly conducted.

Typically the final results are presented in reports using the support of graphs, tables and images to promote the fugitive emission analysis and to suggest proposal for the improvement actions.