Black Cotton Research Articles

Study on Fenton-based discoloration of reactive-dyed waste cotton prior to textile recycling

The aim of this study is to investigate the feasibility of an alternative Fenton-based advanced oxidation process for the discoloration of reactive-dyed waste cotton as a pre-treatment for textile recycling. For that, pre-wetted dark-colored (black and blue) knitted samples of 300 cm2 are treated in 1200mL Fenton-solution containing 14 mM Fe2+ and 280mM H2O2 at 40 °C. Characterization of the textiles before and after the treatments are performed by UV VIS-spectrophotometry measuring color strength, microscopy, FTIR spectroscopy, thermal analysis and tensile testing measuring tenacity and elongation. Afterwards, the cotton is mechanically shredded for qualitative analysis of the recyclability. The color-strength measurements of the black and blue cotton led to discoloration-efficiencies of respectively 61.5 and 72.9%. Microscopic analysis of discolored textile fabric also showed significant fading of the colored textiles. Mechanical analysis resulted in reduced tensile strength after treatment, indicating oxidation of the cellulosic structure besides the degradation of the dye-molecules, also confirmed by reductions in thermal stability found after thermal analysis. Shredding of the fabric resulted in enhanced opening, but shorter remaining fibers after treatment. The findings of this study provide a proof-of-concept for an alternative color-stripping treatment concerning a Fenton-based advanced oxidation process as a pre-treatment for textile recycling.

Experimental evaluation of expansive soil stabilised with sustainable binder incorporating blast furnace slag and bagasse ash

ABSTRACT Civil engineering structures made upon expansive soils known in India as Black Cotton (BC) soils are susceptible to structural damages due to their seasonal swell-and-shrink behaviour. This study focuses on assessing the mechanical performance of BC soil stabilised using unconventional binders, specifically Sugarcane Bagasse Ash (SCBA) and Ground Granulated Blast Furnace Slag (GGBS) with different proportions. The experimental evaluation included Compaction tests, Unconfined Compressive Strength (UCS) tests, Triaxial tests, and Atterberg’s limits tests. Additionally, mineralogical and morphological studies were carried out using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and chemical analysis using x-ray fluorescence spectroscopy analysis (XRF). The results showed that the mixture containing 21% SCBA and 9% GGBS produced cementitious-siliceous-hydrate (C-S-H) molecule, which improved the strength. Based on the soil-binder percentage ratio obtained from UCS tests, a regression equation was developed to estimate consolidated soil strength. The regression model, exhibiting an impressive R2 value of 93.69%, was analysed within the framework of existing empirical correlations by other researchers. This statistical model, with its good fit, is a useful tool for evaluating the compressive strength of stabilised expansive soil. The findings provide insights into successful stabilisation solutions for expansive soils found locally and globally.

Treatments Technology and Mechanisms of East Asia Black Cotton Soil

The East Asia black cotton soil (BCS) cannot be used as embankment filling directly due to its high clay content, liquid limit, plasticity index, and low CBR strength (CBR < 3%). This study evaluates the effects of treating East Asia BCS with lime, volcanic ash, or a combination of both on its engineering properties. Experiments were conducted to analyze the basic physical properties, swelling characteristics, and mechanical properties of the treated soil. Results indicate that lime addition significantly reduces the free swelling rate, improves limit moisture content, increases optimum moisture content, decreases maximum dry density, and enhances CBR value. Although volcanic ash also improves BCS performance, its effects are less pronounced than those of lime. The combined treatment with lime and volcanic ash exhibits superior performance, greatly reducing expansion potential and significantly increasing soil strength. Specifically, a mixture of 3% lime and 15% volcanic ash optimizes the liquid limit, plasticity index, and CBR value to 49.2%, 23.8, and 24.7%, respectively, meeting the JTG D30-2015 requirements and reducing construction costs. The treatment mechanisms involve hydration exothermic reactions, volcanic ash reactions, and semipermeable membrane effects, which collectively enhance the soil’s properties by producing dense, high-strength compounds.

Enhancement of Strength and Compressibility of Black Cotton Soil Using Ground Granulated Blast-Furnace Slag (GGBS)–Cement Kiln Dust Columns

Enhancement of Strength and Compressibility of Black Cotton Soil Using Ground Granulated Blast-Furnace Slag (GGBS)–Cement Kiln Dust Columns

SOIL IMPROVEMENT IN PROBLEMATIC BLACK COTTON SOIL BY USING DRY KOTA STONE SLURRY AND FLY ASH-A STATE OF ART OF REVIEW

Black Cotton Soil (BCS) is particularly rapid-expanding and swelling when it meets water. This trait of soil results in extremely low soil strength and other attributes. Soil stabilization by various stabilizers is required to enhance its characteristics. Stabilization is a technique used to improve the soil's structural integrity. Soil stabilization raises the subgrade's load-bearing capacity, allowing it to better support the pavement and foundation. This is accomplished by increasing the soil's shear strength and regulating its shrink-swell qualities. Expansive soils could have their engineering qualities enhanced via several different means. The problematic soils are either excavated and replaced with excellent, higher-quality material, or treated with an additive. This paper demonstrates an analysis for soil improvement in problematic BCS by using dry Kota Stone Slurry (KSS) and Fly Ash (FA). FA is a byproduct of coal combustion in thermal power plants. It consists of fine particles that are carried away with the flue gases during the combustion process. The findings highlight its potential to address soil-related issues, enhance agricultural productivity, and contribute to sustainable land utilization practices.

An Experimental Investigation for evaluating Fly Ash, GGBS and RHA's Impacts on Black Cotton Soil Stability

An Experimental Investigation for evaluating Fly Ash, GGBS and RHA's Impacts on Black Cotton Soil Stability

Experimental Investigations of stabilization of Black cotton soil

Abstract The technique of stabilizing soil aids in achieving the qualities of soil that are necessary for building projects. Black cotton soils, sometimes referred to as swelling soils, are those soil types that have a propensity to expand and contract in response to changes in moisture content. By increasing the strength of the black cotton soil, this experimental investigation on stabilizing the soil with a certain amount of granite dust produces positive results. The maximum dry density and reduced potential for shrinkage and swelling are found in the black cotton soil mixed with 5% granite. The greatest results are obtained with 10% of the granite mix with black cotton soil since this experiment shows a significant decrease in the ideal moisture content.

Evaluation of Amended Black Cotton Soil Using Bagasse Ash with Liquid Alkaline Activator for Sustainable Pavement Subgrade Performance

Evaluation of Amended Black Cotton Soil Using Bagasse Ash with Liquid Alkaline Activator for Sustainable Pavement Subgrade Performance

Geotechnical performance of black cotton clay in the presence of lead and cadmium solutions for geoenvironmental application

ABSTRACT The usage of bentonites and sand–bentonite mixtures as liners has become prevalent due to their low permeability. However, these materials are scarce and prohibitively expensive in India. Black cotton clay (BCC) was chosen as an alternative clay liner for this research due to its abundance in India and its mineralogical composition. Since heavy metals accumulation in municipal landfills is a rising issue with devastating effects on the ecosystem and human health, in this investigation, two heavy metals (lead and cadmium) were intended as permeants at three different concentrations (100, 500, and 1000 ppm) to imitate the impact of heavy metal leachate on BCC. The essential index and engineering properties of BCC were evaluated and compared under these two permeants from the liner perspective. Experimental results revealed that the free swell index, Atterberg limits, swelling and swelling pressures were reduced for a rise in concentration irrespective of metal type. However, this reduction was more with cadmium permeants compared to lead. The measured swelling data was compared with predicted swelling data using a rectangular hyperbola model, and a good correlation was achieved. The hydraulic conductivity (k) and unconfined compressive strength (UCS) values were increased for a rise in concentration with both metal permeants. At 1000 ppm concentration, the k values were raised to 3.5 and 6.7 times, and UCS values were enhanced by 8.3 and 5.5% for lead and cadmium permeants, respectively. At high concentrations, field emission scanning electron microscopy (FESEM) results showed the formation of huge voids and aggregation.

Performance evaluation of marginal materials in geosynthetic reinforced base layers

The high-altitude regions are prone to natural disasters such as landslides, and tunnelling that generate substantial amounts of debris. Utilising these waste (marginal) materials in the pavement sector offers a viable solution. This study aims to stabilise tunnel muck, landslide debris, and Reclaimed Asphalt Pavement using geosynthetics (geogrid, geocell, double geogrid, and geogrid + geocell) for the base course. Cyclic Plate Load tests were performed on pavement prototypes built with available marginal materials and conventional GSB as the base/subbase course, with Black cotton and silty soil subgrades. The results indicated that geosynthetic reinforcement significantly improved the performance of marginal materials by lowering permanent deformation and increasing design life. The pavement prototypes reinforced with double geogrid and geogrid + geocell indicated rutting performance equivalent to conventional GSB for specific combinations. Additionally, incorporating geosynthetics in pavement layers increased the structural strength of the base layers by a layer coefficient ratio factor ranging from 1.1 to 2.5.

A utility and easily fabricated dual-mode fiber film for efficient and comfortable thermal management

Nowadays, the global climate is constantly being destroyed and the fluctuations in ambient temperature are becoming more frequent. However, conventional single-mode thermal management strategies (heating or cooling) failed to resolve such dynamic temperature changes. Moreover, developing thermal management devices capable of accommodating these temperature variations while remaining simple to fabricate and durable has remained a formidable obstacle. To address these bottlenecks, we design and successfully fabricate a novel dual-mode hierarchical (DMH) composite film featuring a micro-nanofiber network structure, achieved through a straightforward two-step continuous electrospinning process. In cooling mode, it presents a high solar reflectivity of up to 97.7% and an excellent atmospheric transparent window (ATW) infrared emissivity of up to 98.9%. Noted that this DMH film could realize a cooling of 8.1 °C compared to the ambient temperature outdoors. In heating mode, it also exhibits a high solar absorptivity of 94.7% and heats up to 11.9 °C higher than black cotton fabric when utilized by individuals. In practical application scenarios, a seamless transition between efficient cooling and heating is achieved by simply flipping the film. More importantly, the DMH film combining the benefits of composites demonstrates portability, durability, and easy-cleaning, promising to achieve large-scale production and use of thermally managed textiles in the future. The energy savings offered by film applications provide a viable solution for the early realization of carbon neutrality.

Fibre persistence on submerged substrates: The effect of flow rate over extended submersion periods

Through both casework and research, fibres have been found to have the particularly useful ability to persist and remain exploitable after submersion. However, direct analysis of the persistence ability remains in early stages, and in particular, submersion times above a day have not been thoroughly studied. This study aims to both extend understanding of the impact of flow rate and submersion periods of up to 28 days. A blended polyester/cotton green fabric was abraded to increase transfer and then dragged over a black cotton substrate. Six replicates of these substrates were then submerged in artificial flow cells at various flow rates for 28 days. These were illuminated under UV light and photographed prior to submersion, at set times during submersion and after submersion. Another set of six replicates were imaged, submerged into a river and then recovered and re-imaged after 28 days. The population of fibres was then counted using these photographs, and a mix of one-way and two-way ANOVA tests were applied, in combination with Tukey’s HSD, to detect significant differences across time and flow rate categories. Loss predominantly occurred on within the first 24 hours, in agreement with previous work. However, distinct from previous work there was a slow, approximately logarithmic loss over the balance of the submersion period. While significant differences were found between flow categories, there was no clear relationship between flow rate and persistence. The behaviour of the river samples was well-predicted by laboratory samples. 100 % fibre loss was never observed, with the maximum instead being 95.45 %. These results extend the understanding of fibre persistence on submerged substrates beyond the short submersion times in previous literature, and provide some deeper understanding of the impact of flow rate.

Sesmic Comparitive Analysis for Isolated RCC Trapezoidal Footing resting over Black Cotton Soil

Sesmic Comparitive Analysis for Isolated RCC Trapezoidal Footing resting over Black Cotton Soil

Strength Improvement of Black Cotton Soil by using Different Materials

Strength Improvement of Black Cotton Soil by using Different Materials

Sesmic Comparitive Analysis for Isolated RCC Trapezoidal Footing Resting over Black Cotton Soil

Sesmic Comparitive Analysis for Isolated RCC Trapezoidal Footing Resting over Black Cotton Soil

Growth Response and Economics Variability in Hybrid Pigeonpea to Nitrogen and Phosphorus Fertilization

Aims: To study the growth response and economic variability in hybrid pigeonpea to nitrogen and phosphorus fertilization. Study Design: Factorial randomized block design. Place and Duration of Study: A field experiment was conducted on deep black cotton soils of Regional Agricultural Research Station, Lam during kharif season, 2018-19 in hybrid pigeonpea (ICPH-2740). Methodology: The experiment was laid out in factorial randomized block design (FRBD) comprised of four levels of nitrogen in first factor (N1: 20 kg ha-1, N2: 40 kg ha-1, N3: 60 kg ha-1, N4: 80 kg ha-1) and three levels of phosphorus allotted to second factor (P2O5) (P1: 50 kg ha-1, P2: 75 kg ha-1, P3: 100 kg ha-1). Results: The higher values of grain yield (1900 kg ha-1 & 1833 kg ha-1), net returns (Rs.60522/- & Rs.57181/-) and B:C ratio (1.62 & 1.54) were found with application of nitrogen (60 kg ha-1) and phosphorus (75 kg ha-1), respectively. Conclusion: It was concluded that in Krishna agro-climatic zone of Andhra Pradesh, an application of 60 kg N ha-1 and 75 kg P2O5 ha-1 was applied for getting economically higher grain yield in hybrid pigeonpea.

Enhancing Subgrade Properties of Black Cotton Soil through the Combined Use of Sugarcane Bagasse Ash and Ceramic Waste Powder

Enhancing Subgrade Properties of Black Cotton Soil through the Combined Use of Sugarcane Bagasse Ash and Ceramic Waste Powder

A comparative analysis of pozzolanic material and admixture treatment for black cotton soil as a sub-grade layer

A comparative analysis of pozzolanic material and admixture treatment for black cotton soil as a sub-grade layer

Investigation of black cotton soil using prototype testing as a clay core material for embankment dams

Investigation of black cotton soil using prototype testing as a clay core material for embankment dams

Evaluation of hydraulic conductivity and self-healing potential of punctured geosynthetic clay liner

ABSTRACT An experimental study was conducted on the modified geosynthetic clay liner (GCL) specimen by replacing encapsulated Sodium Bentonite (Na-B) with different percentages of locally available black cotton soil (BCS). The specimens with punctured hole sizes of 4, 8, and 12 mm in diameter were tested for hydraulic conductivity and self-healing capacity assessed by improved triaxial apparatus. The flowing permeant was prepared with the heavy metals: iron, zinc, nickel, and total chromium based on the results of the chemical analysis of leachate collected from the municipal solid waste site (MSW). The experiment results were observed at 24, 48 and 72 hours. The results were analysed to identify the best specimen mix (Na-B and BCS) regarding the lowest hydraulic conductivity and highest self-healing potential. The results demonstrated that BCS can be utilized in modified GCL as an impermeable barrier for leachate percolation at the MSW dump site.