The Determination of the Methane Content of Coal Seams Based on Drill Cutting and Core Samples from Coal Mine Roadway

The determination of methane content of coal seams is conducted in hard coal mines in order to assess the state of methane hazard but also to evaluate gas resources in the deposit. In the world’s mining industry, natural gas content in coal determination is usually based on direct methods. It remains the basic method in Poland as well. An important element in the determination procedure is the gas loss that occurs while collecting a sample for testing in underground conditions. In the method developed by the authors, which is a Polish standard, based on taking a sample in the form of drill cuttings, this loss was established at a level of 12%. Among researchers dealing with the methane content of coal, there are doubts related to the procedures adopted for coal sampling and the time which passes from taking a sample to enclosing it in a sealed container. Therefore, the studies were designed to evaluate the degree of degassing of the sample taken in the form of drill cuttings according to the standard procedure and in the form of the drill core from a coal mine roadway. The results show that the determinations made for the core coincide with the determinations made for the drill cutting samples, with the loss of gas taken into account.

Treatment Efficiency of Drill Cuttings Using Thermal Desorption Technology

Aim: The aim of this study was to analyze and determine the treatment efficiency of drill cuttings using the Thermal Desorption Technology. Study Design: Drill cuttings were obtained from a work-over drilling operation with samples obtained at a depth of 2,750m from a typical well for this baseline study. The aim is to analyze the physical and chemical characteristics of the drill cuttings in a laboratory before and after the thermal desorption processes. A second drill cutting sample from another field location at the same depth of 2,750m was used for comparison during the analysis. Place and Duration of Study: Port Harcourt, Rivers state, Nigeria (Laboratory analysis was done at Anal Concept Ltd, Port Harcourt, Rivers state, Nigeria and the thermal desorption unit is situated at the Initiates Plc, Etche LGA, Rivers state, Nigeria). Methodology: A representative sample feedstock of cuttings was collected before and after the thermal treatment. The drill cutting sample was taken from a mixing tank by using a cup and auger. The samples of the cuttings were made for each case of the grab samples, and the samples later transferred into 500mL glass bottles. The sample contaminants were analyzed in a chemical laboratory using standard methods for determining the pH level, Electrical Conductivity, Moisture Content, Organic Pollutants and Heavy Metals. Results: The result showed significant reductions in all the pollutant concentrations after the drill cuttings were treated with the Thermal Desorption Unit. Moisture Content (MC) and the Total Petroleum Hydrocarbon (TPH) decreased significantly by 86% and 93% respectively. The concentration of the combination of Benzene, Toluene, Ethylbenzene and Xylene (BTEX) reduced drastically by 98% and the heavy metals concentration levels were also reduced after treatment with the TDU. Also, the laboratory analysis result of the treated drill cuttings shows that the pH level, Electrical Conductivity, Moisture Content, Organic Pollutants and Heavy Metals concentrations did not exceed the recommended Department of Petroleum Resources (D.P.R) limits. Conclusion: This research reveals that the thermal desorption technology is the most economical, efficient and environmentally friendly method of waste management due to its contaminant removal efficiency. This method enhances product recovery and subsequent recycling which helps to reduce environmental impact and prevent economic losses.

Fabrication of Low-Temperature Sintering Building Bricks Using Drilling Cutting and Geopolymeric Technology

This study explores the practicability of using drill cutting (DC) as raw material to fabricate building bricks through the high-temperature sintering method and low-temperature geopolymeric setting (LTGS) process. Drilling mud can be recycled and reutilized after certain treatment procedures and is considered as a non-hazardous waste. However, the treatment process is time-consuming and not cost-effective. For the sintering method, low porosity and high mechanical strength bricks can be sintered at temperatures above 800 °C and meet CNS standards. For the low-temperature geopolymeric setting process, sodium silicate was selected as an activating agent for geopolymerization of drill cutting. Several process parameters, such as Si2O/Na2O modulus of alkali solution and low-temperature geopolymeric setting temperature, were investigated. The physical and mechanical properties of the fabricated brick were evaluated. According to the test results, 72.4 MPa compressive strength building bricks with low porosity (13.9%) and water absorption (6.0%) can be fabricated with 2.0 Si2O/Na2O alkali solution at 500 °C. The drill cutting brick fabricated not only meets the CNS 382.R2002 common brick standard, but also solve its disposal problem.

NMR DRILL CUTTING ANALYSIS: METHODOLOGY EVALUATION AND OPERATIONAL BEST PRACTICES

Drill cuttings are available in every well drilled and NMR is a powerful tool for characterization of rocks and fluids. It is thus desirable if useful petrophysical information can be derived from NMR drill cutting analysis. However, previous studies have shown that there are many uncertainties associated with cutting analysis by using NMR, such as (1) the small cutting size may not be representative of the formation rock pore system, and (2) the effect of drilling fluids which may penetrate and clog the pore space may result in uncertain pore typing and pore surface characterization. In this paper, based on a detailed methodology evaluation study using cuttings with different rock types, cutting sizes, and with different mud contaminations, we present experimental evidence to show (1) the best operational practices to remove mud and excess fluid contamination, and (2) the minimal cutting size required to obtain useful petrophysical information. In addition, we will also provide recommended cuttings preparation procedures and set the practical expectations for NMR drilling cutting analysis.

Experimental analysis of process parameters in drilling nimonic C263 alloy under nano fluid mixed MQL environment

Nimonic C263 is a super alloy and it is difficult to cut. As this alloy possess high proportion of chromium, cobalt, and molybdenum, which fortify the material by solution hardening, which inhibits the dislocation movement, resulting in higher plastic deformation. In this research, an attempt has been made to model, analysis and investigate the machining characteristics such as thrust force, temperature at drill cutting edge, flank wear and surface finish during drilling of this alloy using silver nano fluid mixed Minimum Quantity Lubrication (MQL) environment. Residual stress at various combinations of process parameters was also observed and discussed. RSM based empirical models of the process parameters and optimization of multi response was developed. Thrust force, Temperature at drill cutting edge, surface roughness and tool wear affected by feed rate (percentage of contribution-60%), spindle speed (percentage of contribution-88.63%), spindle speed (percentage of contribution-71.42%) and feed rate (percentage of contribution-67.76%) respectively followed by other parameters.