Mud logging is a process commonly used in the oil and gas industry to monitor the physical characteristics and composition of rock cutting obtained during the well drilling process. The Flame Ionization Detector (FID) typically uses hydrogen as a fuel and oxidant in the conversion process. Hydrogen gas generation offers benefits over gas cylinders.
Mud logging also involves the analysis of gases present in the mud circulated through the well bore (Advanced Industrial Chemistry Corp., n.d.). A mobile laboratory is typically situated by the mud logging company near the drilling rig, on the deck of an offshore drilling rig, or on a drill ship. Identifying the presence of oil and gas helps to determine the potential of the well (Geomore.com, 2014).
Detection of total organic content
One of the most critical parameters is the determination of the total organic content (TOC) of the rock, which is directly related to the economic value of the well. The TOC is determined by heating the sample to expel the hydrocarbons and monitoring their concentration using a Gas Chromatograph with an FID. Hydrogen is typically used as a fuel and an oxidant to convert the various organic compounds into ions. The presence of the ions is then detected by a pair of electrodes and a sensitive ammeter. The FID requires a supply of hydrogen at a flow rate of approximately 40 mL/min at a pressure of 50 psi.
Hydrogen gas can be obtained from high-pressure cylinders. While this is a satisfactory approach, using an on-site hydrogen generator offers significant benefits over gas cylinders, especially when one considers the logistical issues associated with the delivery of gas to an onshore or offshore oil drilling rig.
Benefits of using an on-site hydrogen gas generator
An on-site hydrogen gas generator is considerably safer than cylinder gas as only a small amount of generated gas is present at any given time, and the gas is ported directly to the monitoring instrument. If a leak occurs, only a small amount of gas is dissipated into the laboratory. In contrast, serious hazards exist with gas cylinders including injury from transporting heavy cylinders, and the potential of a leaking cylinder causing an explosion.
Cost savings is another benefit of using an in-house generator. Operating costs are low as hydrogen is produced by using deionized water and electricity. The maintenance costs are minimal and only entail periodic filter replacement. In comparison, the expense of gas cylinders includes not only the purchase price, but other costs including transportation, installation, and instrument downtime due to calibration.
A Parker hydrogen generator offers a continuous supply of high purity hydrogen in a compact design that uses only one square foot of bench space. Innovative control software ensures unrivaled operational safety and reliability. Remote networking software allows up to twenty-seven generators to be actively controlled from one central computer.
This post was contributed by the Gas Generation Technology Blog Team, Parker Hannifin.