Method for monitoring efficiency of drilling fluid purification system

Abstract

FIELD: monitoring efficiency of drilling fluid cleaning systems.SUBSTANCE: invention relates to methods for monitoring the efficiency of drilling fluid cleaning systems in removing particles of drilled rock (cuttings) and can be used in the oil and gas production industry. The method for monitoring the efficiency of a drilling fluid cleaning system involves taking a first sample at the inlet and a second sample at the outlet of the cleaning system. For each sample, the concentration of cuttings is determined using a combination of X‑ray fluorescence analysis and Fourier‑transform infrared spectroscopy, after which the cleaning efficiency coefficient is calculated.EFFECT: technical result is an increase in accuracy, real‑time monitoring, and the ability to assess the effectiveness of both the entire purification system and its individual stages.4 cl

Description

[0001] Field of technology to which the invention relates

[0002] The invention relates to the oil and gas production industry, specifically well drilling, and specifically to methods for monitoring and controlling the process of cleaning drilling mud from cuttings. The invention can be used to evaluate the performance of both the entire drilling mud cleaning system and its individual stages (vibrating screens, hydrocyclones, centrifuges) in real time.

[0003] Technology Level

[0004] Various methods for monitoring drilling fluid parameters and assessing the effectiveness of its cleaning are known from the prior art.

[0005] A known method for remotely monitoring mud parameters at the wellbore outlet involves measuring the density, level, and flow rate of the mud in the drilling rig's trough as it circulates through a closed process loop, followed by cleaning (RU Patent No. 2602560, published November 20, 2016). Additionally, the mud density is measured after cleaning, and the cuttings parameters are determined using calculated relationships. A disadvantage of this method is the indirect nature of the determination of cuttings content, which reduces the accuracy of cleaning effectiveness assessment.

[0006] A system for automatically controlling the colloidal phase content and volume of drilling fluid is known. It includes sensors monitoring the colloidal phase volume and content (using indirect parameters such as viscosity and density), as well as a flow meter (USSR Patent No. 659722, published July 30, 1979). A disadvantage of this system is the use of indirect methods for assessing the composition of the fluid, which does not allow for the rapid and reliable determination of the concentration of cuttings—the content of drilled rock.

[0007] The closest technical approach to the claimed invention is a method implemented in a drilling fluid monitoring system using X-ray fluorescence (XRF) and Fourier transform infrared (FTIR) analysis (Patent EP No. 0628165, published December 14, 1994). However, this method is focused on a general analysis of drilling fluid components (barite, clay, weighting agents) and does not involve calculating the cleaning system's efficiency based on cuttings concentration, nor does it provide for cascade monitoring or real-time operation.

[0008] The disadvantages of known solutions are:

[0009] - low accuracy of existing methods for determining the cuttings content in drilling mud based on indirect measurements (viscosity, density, flow rate);

[0010] - lack of possibility of direct and continuous control of sludge concentration at the inlet and outlet of the cleaning system;

[0011] - impossibility of assessing the efficiency of individual stages of the cleaning system;

[0012] - lack of ability to quickly adjust the operating modes of the cleaning equipment.

[0013] Disclosure of the essence of the invention

[0014] The technical problem that the claimed invention is aimed at solving is the low accuracy of existing methods for determining the content of cuttings in drilling mud and, as a consequence, the low reliability of assessing the efficiency of drilling mud cleaning systems.

[0015] The technical result of the invention is:

[0016] - increasing the accuracy of determining the efficiency of the drilling mud cleaning system by directly measuring the concentration of sludge using physical and chemical analysis methods;

[0017] - providing the ability to monitor the efficiency of the cleaning system in real time;

[0018] - providing the ability to control the efficiency of both the entire cleaning system as a whole and each of its individual stages.

[0019] The essence of the invention is that the method for monitoring the efficiency of a drilling mud cleaning system includes taking a first sample of drilling mud at the entrance to the cleaning system (or at the entrance to a separate cleaning stage) and taking a second sample of drilling mud at the exit from the cleaning system (or at the exit from a separate cleaning stage).

[0020] Distinguishing features: For each sample, the concentration of drilled rock particles (slurry) is determined using a combination of physicochemical analysis methods—X-ray fluorescence analysis (XRF) and Fourier transform infrared spectroscopy (FTIR). Based on the obtained concentration values, the cleaning efficiency is calculated in real time using the formula:

[0021] E = 100 × (C вх - WITH вых ) / WITH вх

[0022] where E is the efficiency of the drilling mud cleaning system, %; C вх- concentration of sludge in the drilling mud at the entrance to the cleaning system (or at the entrance to the cleaning stage), kg / m3 3 ; WITH вых - concentration of sludge in the drilling fluid at the outlet of the cleaning system (or at the outlet of the cleaning stage), kg / m3 3 If necessary, concentration C вх and C вых , can be expressed in other units of measurement.

[0023] Additional: The operations of sampling, concentration determination and efficiency calculation can be performed sequentially for each stage of the cleaning system (e.g. vibrating screen, hydrocyclone, centrifuge) to determine the cascade efficiency.

[0024] Using a combination of XRF and FTIR ensures high accuracy and selectivity in cuttings determination, as these methods allow for the identification of the elemental and mineral composition of the solid phase in the drilling fluid. Automation of measurements is also possible for real-time operation.

[0025] The technical result is achieved due to the fact that for the first time, direct rather than indirect measurement of sludge concentration is used to evaluate the cleaning efficiency, which eliminates errors associated with changes in viscosity, density and other rheological parameters of the solution under the influence of uncontrolled factors.

[0026] Brief description of drawings (if included in the application)

[0027] Implementation of the invention

[0028] The method is as follows.

[0029] On a drilling rig equipped with a drilling fluid cleaning system (including, for example, a vibrating screen, hydrocyclone, and centrifuge), sampling points are established. The first sampling point is located before the inlet to the cleaning system (e.g., in a receiving tank or chute). The second sampling point is located after the outlet of the cleaning system (in a cleaned solution tank). For cascade monitoring, additional sampling points are established after each element of the cleaning system.

[0030] Sampling is performed at a set frequency, ensuring real-time monitoring (e.g., every 5-15 minutes). The collected samples are sent for analysis to a measuring system including an X-ray fluorescence analyzer and a Fourier transform infrared spectrometer.

[0031] X-ray fluorescence analysis allows for the determination of the elemental composition of the solid phase of a sample and the identification of drilled rock particles based on their characteristic chemical elements (silicon, calcium, aluminum, iron, etc., depending on the rock type). Fourier transform infrared spectroscopy complements X-ray fluorescence by identifying mineral phases and organic components, increasing the reliability of determining the concentration of the cuttings rather than other solid particles (weighting agents, colloidal particles).

[0032] Based on the analysis data for each sample, the sludge concentration is calculated. Then, the efficiency for the treatment system as a whole or for each stage is calculated using the formula provided.

[0033] The obtained efficiency values ​​can be used for:

[0034] - operational assessment of the state of the cleaning system;

[0035] - making a decision on the need to adjust the operating modes of the equipment (for example, changing the vibration force of the vibrating screen, the feed speed of the centrifuge);

[0036] - diagnostics of failure of individual elements of the cleaning system.

[0037] Thus, the claimed method allows for a highly accurate assessment of the contribution of each element of the cleaning system and the identification of the most problematic stages.

[0038] List of nucleotide and / or amino acid sequences (if nucleotide and / or amino acid sequences are used to characterize the invention).

[0039] Information on the results of preclinical studies of medicinal products and clinical studies of medicinal products (provided at the initiative of the applicant on separate sheets for the purpose of removal from publication of information on the issuance of a patent).

Claims

1. A method for monitoring the efficiency of a drilling mud cleaning system, which includes taking a first sample at the inlet and a second sample at the outlet of the cleaning system, characterized in that for each sample the concentration of the cuttings is determined using a combination of X-ray fluorescence analysis and Fourier transform infrared spectroscopy, after which the cleaning efficiency coefficient is calculated.

2. The method according to paragraph 1, characterized in that the determination of the sludge concentration is carried out in real time.

3. The method according to paragraph 1 or 2, characterized in that the cleaning efficiency is calculated using the formula E=100×(C вх - WITH вых ) / WITH вх 4. The method according to any of paragraphs 1-3, characterized in that the said operations are repeated sequentially for each stage of the cleaning system with determination of the cascade efficiency.