Source Rock Analyzer (SRA):
Quick Start Guide (from SRA_QSG_371T_draft)
K. Fujine (10/20/09); revised/approved by D. Houpt (8/13/13), revised V.Percuoco 371T | July 2017 (7/26/17)

Introduction

This quick start guide contains operational procedures for the Source Rock Analyzer (SRA).See the SRA Analyzer User Guide and Advanced User Guide for additional information.
Pyrolysis analysis is conducted on dried, ground sediments or borehole source rock for safety monitoring as well as for scientific purposes. The analysis yields information about thermal maturation and source of hydrocarbons at the drilled site, as well as petroleum potential. The data obtained from the Rock-Eval/TOC analyses are defined by the following parameters.

Apparatus, Reagents, & Materials

Hardware

The SRA system consists of the following main components (Figure 1): Autosampler, Main control unit: oven and detector temperature control unit and gas flow controllers, Infrared (IR) section, Combustion with gas separation and FID (pedestal, oven, and conversion FID), and Cahn electrobalance dual balance system
Image Modified
Figure 1. Main Components of the SRA System.

Laboratory Apparatus for Sample Preparation

–Autosampler tray (1/4)
–Forceps, small spatula, and sample filler
–Crucible and crucible holder
–Weighing paper
–Recording chart

Reagents

–Methanol
–Compressed gases: H₂, 60–80 psi, He, 60–80 psi, Air, GC grade, 60–80 psi, and laboratory grade, 60–100 psi

Standards

–Colorado Oil Shale Silica (COSS) house standard
–Standard material (99986)
-Weatherford Laboratories SRA Rock Standard 533

Sample Preparation

Sediments and sedimentary rock samples logged into the LIMS system as SRANL are analyzed by SRA. During sample preparation, keep in mind that sample container numbers must correlate with autosampler place numbers.
Freeze-dried bulk samples are crushed by hand or electric mill, then homogenized using a mortar and pestle. Prepare a weighing chart similar to that found below, and record sample ID, mass, and container number in the weighing chart.

Sample Analysis

Preparing the Instrument

The SRA must warm up for 3 hr before operation. Perform the following steps to prepare for sample acquisition (Note: the onboard technician will warm up the instrument):

1. Open H₂, He, O₂, and air gas lines. Note: Verify gas gauge pressures using the gas flow meter.
2. Turn on the SR Analyzer power and PC.
3. Individually test the H₂, O₂, He, and oxidation air gas lines. With a gas flow meter verify gas flows correspond to the following values: H₂: 65 ml/min, He: 100 mL/min, Air: 300 mL/min, Oxidation Air: 250 mL/min. H₂, and O₂ lines are beneath the FID cover. The helium and oxidation air line is connected to the base of the sample pedestal.
4. Double-click the TStationAcq.exe shortcut icon on the desktop to open the software Main Menu.
5. Click Preview to confirm oven and FID temperatures. Values will be <300°C. If after 10–15 min oven and FID temperatures have not increased, proceed to Steps 5 and 6.
6. Click Configuration and select the Temperatures tab
7. Set desired temperature and click Send Temperatures Immediately. Note: Except for this action, do not change any values on any tabs in the Configuration screen.

Setting up the Software

Prepare the software for data acquisition by creating a data folder, editing the method (if needed), and editing the sequence table.

Creating a New Folder

Data (CSV and ROW files) are saved into the expedition-specific data folder with the PAS file (sequence record) and PAR file (method) with respect to each sequence (batch).
Open the Data folder at C:\Program Files\Thermal Station\Data, and create a new folder named EXPxxx where xxx is the expedition number (or xxxx in the rare cases where the expedition has a letter designation with it).

Editing the Method

The method does not need to be edited for regular onboard measurements (i.e., safety monitoring) except for the standard information. The onboard laboratory specialist will edit the fields in the Standard tab if the standard material changes. In that case, one blank, one standard, and one known sample (house standard) must be measured to confirm calibration. The default method is toc_580.SRA.sram

Editing the Sequence Table

A sequence table represents an analytical batch. After each batch, the sequence table is saved into the expedition-specific data folder. A typical sequence table contains the following:
–Data File name (one for each QA/QC and unknown sample). Examples: Blank: OTHR468061, Standard: PWDR39980915, Calibration verification standard: PWDR468051, Unknown sample: textID = LIMS text ID.
–Sample ID: must be identical to the Text ID or the LIMS uploader will reject the file
–Method: toc_580SRA.sram
–C#: container number (must match autosampler place number, as recorded in the weight recording chart)
–Sample Weight: from weight recording chart (mg)
–Acq Type: acquisition type: BLK = cal blank, STD = cal standard, TPH = unknown or QA/QC samples
Edit the sequence table as follows:

Running Samples

To analyze samples, fill in the Acquisition Setup screen and confirm sample information on the Analysis screen.

QA/QC

Calibrating the Instrument

The first sequence for an expedition must include a Blank and a Standard to calibrate the SRA each time the instrument is turned on after power off (e.g., loss of power). After this initial calibration, a Blank and a Standard should be measured once per day to verify calibration of the SRA. If the standard is outside the acceptable limits, the IR cell should be recalibrated.

Analytical Batch (Sequence)

An analytical batch is referred to as a sequence. Each sequence contains the following samples:
–Calibration blank (CB): contains no material; mass = 0; include at the beginning of the sequence
–Calibration standard (CS): ~80 mg of CS material; include 1 per 50 samples or every day
–Calibration verification standard (CV): 1/10 samples, either CS (60 mg), COSS (80 mg), or STD 999986 (60 mg), or STD 533 (PWDR3998091, 100 mg)
–QA/QC blank: empty, used crucible (mass = 1) or empty crucible as unknown (TPH)
–Unknown sample(s) (TPH): 50–70 mg powdered sample (max = 200 mg)

Data Handling

Results are stored in the LIMS database associated with an analysis code and an analysis component, component value, and component unit. Analysis codes and their components, definitions, and units are listed below. Use Spreadsheet Uploader to transfer data from a Sequence Report to LIMS. Complete fields in Spreadsheet Uploader with the following parameters: Analysis: SRANL, Instrument: SRA, Display Flag: T, and the rest according to the table below.
Table 1: LIMS components and units

SRA results are printed to a PDF file, which, along with the corresponding CSV file, are uploaded into the LIMS.

Creating a PDF File

Uploading Data to LIMS

Health, Safety, & Environment

All laboratory specialists must complete required safety training before operating the SRA instrument.

Compressed Gases

• Always wear safety glasses when handling and using compressed gases.
• Hydrogen gas is highly flammable. Be careful with ignition sources and oxidizers.
• Check for leaks in compressed gas lines.
• Use only wrenches approved for use on compressed gas tanks and lines.
• Ground all equipment and lines associated with hydrogen usage.

High Temperatures

• High oven and detector temperatures (325°–600°C) are reached during operation. Use proper heat protective equipment when operating the instrument.
• Make sure the FID cover is always installed during operation to protect from burns.

Archive Versions

SRA User Guide: 29th September 2022

LMUG-SRAQuickStartGuide-230220-1920-166.pdf