Closed Gas Sampling System for Drilling Mud Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mud logging systems lack quantitative estimates of gas release volume due to atmospheric exposure and inaccuracies in gas measurement during core sampling, necessitating a method for continuous, accurate gas analysis during drilling operations that prevents gas dilution and contamination.
Innovation Solution
A closed system is implemented to capture and process desorbed gases from the drill fluid and cuttings at the wellhead, using a rotary seal and cyclonic separator to separate gases from liquids and solids, with ongoing analysis and data logging to correlate gas release with drilling depth and progress, ensuring accurate gas content assessment per unit volume of strata drilled.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional mud logging systems are used to sample gases from drill mud, then gas detection is possible, but quantitative estimates of gas release volume cannot be obtained due to atmospheric exposure and sampling inaccuracies
Solution Approach 1:
The patent implements a closed-circuit sampling system that maintains an inert atmosphere throughout the gas sampling process. The sampling equipment is filled with inert gas before use, and all connections are sealed to prevent atmospheric air ingress. This ensures that gases detected during mud logging are not diluted or contaminated by atmospheric gases, enabling accurate quantitative measurement of gas release volume from the drill mud.
Solution Approach 2:
The patent introduces an intermediary transfer system that moves gas samples from the drill mud through a sealed circuit to the detection equipment. A gas transfer line with sealed connections serves as the intermediary pathway, allowing gas to be transported without exposure to the atmosphere. This intermediary system prevents gas loss and maintains sampling integrity throughout the measurement process.
2Measurement precision
If core sampling is used to obtain gas constituents from coal seams, then gas content analysis is possible, but gas is lost during transit to the surface and measurement inaccuracies occur
Solution Approach 1:
The patent enables continuous gas sampling during the drilling operation itself, eliminating the discontinuous process of core retrieval and laboratory analysis. The closed-circuit sampling system operates continuously as the drill mud circulates, providing real-time gas content measurements at the rate of drilling. This continuous action eliminates transit time losses and maintains constant pressure conditions, ensuring measurement precision.
Solution Approach 2:
The patent performs gas sampling and analysis during the drilling process rather than after core retrieval. By conducting the sampling action preliminarily during the drilling operation, the system avoids the subsequent transit period that causes gas loss. The closed-circuit system is prepared and operational before sampling begins, allowing immediate analysis of gas constituents as they are released from the formation.
3Quantity of substance
If open sampling above the shale shaker is used, then gas detection is possible, but the system lacks quantitative capability and allows gas dilution by air
Solution Approach 1:
The patent employs a closed-circuit sampling system that maintains a controlled inert atmosphere throughout the entire gas handling process. The sampling equipment, transfer lines, and detection instruments are all sealed within this inert environment, preventing atmospheric air from entering and diluting the gas samples. This ensures accurate quantitative measurement of gas volume without contamination.
Solution Approach 2:
The patent replaces the traditional open mechanical sampling system with a sealed, automated closed-circuit system. Instead of manual sampling above the shale shaker where air can enter, the system uses automated gas transfer through sealed connections and electronic detection. This substitution eliminates the mechanical vulnerabilities to atmospheric contamination while maintaining quantitative measurement capability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach provides a dynamic, accurate measurement of gas release volume and content per unit volume of strata, minimizing gas loss and contamination, enabling precise determination of gas-bearing strata characteristics during drilling operations.
Implementation Method 1
using a rotary seal and cyclonic separator to separate gases from liquids and solids
Implementation Method 2
using a rotary seal and cyclonic separator to separate gases from liquids and solids
Implementation Method 3
capturing any gasses desorbed from the formation as well as from the cuttings generated by the drilling operation
Data Source
AI summary
A gas analysis system for determining the gas content of subterranean strata. A boring operation is commenced to form a borehole into or through a subterranean formation, such as a coal or shale formation to determine the gas content thereof. The drill fluid, cuttings and any desorbed gas is carried from the downhole location to surface analysing equipment in a closed system, so that the desorbed gases are not exposed to the air. The drill stem is capped or sealed at the surface, as well as the wellbore annulus to effectively seal the drill liquid, cuttings and desorbed gasses. The drill fluid, cuttings and desorbed gasses from the formation are coupled from the wellhead apparatus to the gas processing equipment via a closed system so that the constituents and volume of the gas can be determined.