Ash Content Value Research Articles

Effect of high-pressure pyrolysis on syngas and char structure of petroleum coke

Petroleum coke, a byproduct of petroleum refining, is considered a potential alternative fuel owing to its low ash content and high calorific value. This study aims to enhance our understanding of the pyrolysis process and its potential applications by investigating the effect of pressure on the pyrolysis of petroleum coke, focusing on changes in its syngas composition and char structure. High-pressure pyrolysis was employed to explore structural changes, decomposition pathways, and gas production. High pressures increase the residence time and promote secondary pyrolysis, leading to the increased production of hydrogen. Also, high pressure can promote gasification reactions such as methanation. The influence of pressure on the chemical and physical structures of the produced char was also observed. Higher pressures resulted in more active secondary pyrolysis, causing a decrease in the aromatic groups and an increase in the aliphatic and oxygen-containing groups in the char. The surface area and porosity of char increased at higher pressures, enhancing its reactivity and gasification rate. Overall, this study provides valuable insights into the effects of pressure on petroleum coke pyrolysis, shedding light on its potential as an alternative energy resource and highlighting changes in gas composition and char structure under various pressure conditions.

FT-IR Characterization and Determination of Mycotoxins (Aflatoxins) (AF’s) from Branded & Unbranded Mixed Spice Samples

Background: The global spice market is essential to food industry and public health due to the widespread use of spices as flavor enhancers, preservatives, and medicinal components. However, the quality of spices can be compromised by the presence of mycotoxins, specifically aflatoxins, which pose significant health risks. Ensuring the quality and safety of spices, both branded and unbranded, is of paramount concern, especially in regions with high humidity and temperature that can facilitate fungal growth and mycotoxin production. Objective: This study aimed to assess the quality of branded and unbranded spice samples from Sindh, Pakistan, by determining their ash content, moisture level, oil composition, and mycotoxin (aflatoxin) content to ensure their suitability for consumption and adherence to food safety standards. Methods: A total of ten spice samples (five branded and five unbranded) were collected from different cities in Sindh province, Pakistan. Ash content was measured by high-temperature oxidation, while moisture content was quantified through oven drying. Oil was extracted using a Soxhlet apparatus, and its quality parameters, including free fatty acid (FFA), peroxide, iodine, and saponification values, were determined using standard AOCS methods. Aflatoxins were quantified by employing an official AOAC method. Additionally, FT-IR spectroscopy was utilized for qualitative analysis of the spice oils. Results: The ash content varied widely, with the highest in unbranded samples at 18.33% and the lowest in branded at 5.67%. Moisture content across all samples was within the safe limit of 5-10%, with the highest at 4.46% and the lowest at 2.22%. The oil content ranged from 5.96% to 14.56%, with unbranded samples showing higher values. FFA values exceeded the standard 0.1% in all samples, indicating a potential quality concern. Peroxide values were higher than the standard 2 meq/mol in most samples, raising concerns about oxidative stability. Aflatoxin levels were within the EU regulatory limits, suggesting acceptable levels for consumption. FT-IR analysis corroborated these findings, revealing no significant differences in the spectral profiles between branded and unbranded samples. Conclusion: The study concluded that while moisture content and aflatoxin levels in the spice samples complied with safety standards, there were notable concerns regarding the ash content, oil quality, and peroxide values. These findings highlight the necessity for regular quality control measures and adherence to food safety regulations to ensure the safety of spice consumption.

Determination of Mineral Content and Physico-Chemical Properties of Apis Honey from Karnataka State

The present investigation analyzed Apis honey samples of dorsata, cerana, mellifera and florea spp. from Coorg and Kolar districts of Karnataka. The physical parameters, pH, optical density, viscosity, and moisture contents were analyzed for the Apis honey samples and were found to comply with international standards. The efficacy of Apis honey in medical research chiefly depends on its mineral constituents. Hence, the total ash content was calculated using the Ivanov and Chevanakova methods. An atomic absorption spectrophotometer and flame photometer were used to quantify minerals in honey samples. The total ash range was between 0.24±0.2 to 0.65±0.1 per cent. The F-test and ANOVA values of the total ash content of honey samples were significant at 5% levels. Honey of Apis dorsata had 4.33±0.01 ppm±SD of Calcium and 1.69±0.02 ppm±SD of Magnesium; 0.004±0.0001 ppm±SD of Chromium 0.09±0.02 ppm±SD of Iron was found in honey of Apis florea. Likewise, honey of Apis cerana had Copper (0.05±0.002 ppm±SD), Manganese (0.08±0.002 ppm±SD), Phosphorus (0.49±0.02 ppm±SD), Potassium (40.44±0.09 ppm±SD) and Sodium (4.37±0.06 ppm±SD). Zinc (0.06±0.002 ppm±SD) was present in honey of A. mellifera. All the mineral nutrients studied were within the compliance range and determined to be statistically significant (p< 0.05). It was concluded that the Karnataka Apis honey maintains its good standards.

Impact of densification process on unprocessed biomass and post-hydrothermal carbonization

The pulp and paper industry use biomass residues, such as paper sludge and bark as fuel to provide energy for their plants. However, issues such as high-water content or low heating value limit the amount of energy that can be utilized. Processes to improve heat generation include biomass densification, which facilitates transportation and handling and can increase energy yield. However, the technical feasibility of briquetting is a function of the feedstock and preprocessing. This study introduces a novel approach to briquette production from biomass residues by utilizing wet biomass with water as a natural binder, contrasting with conventional methods that require forced drying and/or the addition of binders. The objective of this research was to investigate the impact of briquetting both unprocessed biomass and post-hydrothermal carbonization. The study focused on manufacturing briquettes derived from different sources, including bark (Balsam fir), paper sludge, and hydrochar of paper sludge. The feedstock was characterized for ash content and higher heating value. Biomass particle size (range), moisture content (range), process temperature (range), process pressure (range), and process residence time (range) were varied in briquetting experiments to determine conditions to produce high-quality briquettes with minimal energy input. Moisture content as high a 50 wt% in feedstock produced technically feasible briquettes, with appropriate physical-mechanical properties (durability, volumetric expansion and apparent density), and energetic potential (calorific value). The addition of heat (pressing temperature of 150 °C) during the pressing process resulted in briquettes with enhanced physical-mechanical, and energetic properties, surpassing those produced at room temperature. Further tests with additional steps in the production process are required to meet commercialization standards in Canada, but the treatments conducted in this study effectively improved the energy potential of biomass for internal industrial energy gains.

Fortification of conventional Buffalo meat sausage with ash gourd peel enhances shelf life, nutritional, functional and microstructural characteristics

In recent years, food fortification has been seen as one of the important approaches to address nutrients deficiency and also considered as a source of a sustainable form of intervention to reach a wider population. Therefore, the aim of our study was to develop Buffalo meat sausage by incorporating dehydrated ash gourd peel powder (DAGPP). Four sausage formulations were prepared with three levels of DAGPP inclusion (4%, 8%, and 12%) along with a control sample. DAGPP-incorporated sausages were compared with the control sample in terms of scanning electron micrograph (SEM), crude fiber content, antioxidant activity, total phenolic content, and sensory and textural attributes. The storage studies (at 0 °C) were carried out for analysis of physicochemical properties (moisture content, protein content, ash content, pH and TBA value), color parameters (a*, b* and L* values) and microbiological characteristics. Our results showed that crude fiber content and mineral content increased from 0.74% to 6.33% and 1.94% to 2.74%, respectively, on the first day of the study. TBA value decreased from 0.207 to 0.133 (mg of malonaldhyde/ kg sample) on the 14th day of the study. Microbiological analysis revealed that the total plate count, yeast and mold count reduced from 2.87 to 2.12 log cfu/g and 1.93 to 1.38 log cfu/g, respectively, although no coliform was detected. The highest sensory score was achieved for the sample containing 12% DAGPP ie; 7–9. Based upon our findings, we found that the fortified meat sausages had better microstructure and sensory score, increased nutritional value, crude fiber, shelf life as well as high antioxidant activity. Therefore, DAGPP fortified meat sausage can be considered as one of the important sources for proteins and minerals for the under-nutrition population. However, profiling of the fortified food would be warranted to investigate micronutrients along with other functional characteristics.

Chemical Characteristics of Scales, Skin And Bones of Snakehead Fish (Channa Striata) After Soaked With Sodium Hydroxide Solution

Snakehead fish is one of the freshwater products that has potential in South Sumatra. Utilization of snakehead fish as a side dish and diversification product is for typical Palembang food processing. Most of these preparations used meat as a raw material, leaving waste scales, skin and bones which had the potential to be used as raw materials for collagen. One of the stages of collagen production was soaking in NaOH. The aim of this research was to examine the chemical properties of scales, skin and bones of snakehead fish after soaking in NaOH. The soaking process was carried out in 0.05M NaOH for 6 hours and the water was changed every 2 hours with a ratio of waste to NaOH solution of 1:10. The parameters analyzed included water content, ash content and protein. The results showed the proportion of scales, skin and bones of snakehead fish respectively of 6% scales, 5.7% skin and 4.20% bones. Proximate analysis tests showed levels in snakehead fish scales of 55.67%, skin by 81.15% and bones by 50.80%. The average value of ash content was in snakehead fish scales of 48.14%, skin by 9.27% and bones by 55.42%. The average value of protein content was in snakehead fish scales by 29.60%, skin by 67.59% and bones by 23.66%.

The Impact of Cluster Fig Fruits Powder Addition on Nutritional and Organoleptic Properties of Some Healthy Food Products

Cluster fig, also known as goolar in Hindi, is a medicinal fruit abundant in India, offering a rich source of iron and other essential micronutrients. Wheat, a staple in the Indian diet, is energy-dense and provides valuable carbohydrates and proteins. Pearl Millet, the most commonly grown type of millet, is renowned for its high calorie, vitamin, and mineral content. Mung beans, part of the legume family, are calorie-dense and a great source of protein and polyunsaturated fatty acids. In this study, cluster fig powder, germinated wheat flour, germinated mung bean flour, germinated pearl millet, carrot powder, and beetroot powder were utilized for product development. Two products were developed with three treatments, varying the quantity of ingredients. Sensory and proximate analysis were conducted on the developed products, with each treatment having three different replications to minimize errors during analysis. Based on the sensory evaluation, T1 is considered the best among all treatments, with a moderate ratio of cluster fig contributing to its taste and flavor. The ash content varied across replications, with the control product having the highest ash content of 11.03%, likely due to experimental errors. Treatments T1, T2, and T3 had ash content values of 10.19%, 10.55%, and 10.89%, respectively. Organoleptic evaluation indicated that as the quantity of cluster fig increased, the taste became bitter, leading to decreased acceptability. Proximate analysis revealed that an increase in the quantity of cluster fig resulted in higher iron and zinc content in the products. This study highlights the organoleptic acceptability and nutritive & medicinal properties of cluster fig, providing insights into the appropriate quantities of cluster fig powder and other ingredients for various processed convenience healthy foods. The research emphasizes the use of cluster fig, a readily available fruit in India, which has not been previously utilized in convenience food products.

DEVELOPMENT OF COMPOSITE MATERIALS FOR TRICYCLE BRAKE PADS

Coconut fiber and rice dust are locally sourced, developed, and evaluated as agro-waste materials to replace carcinogenic asbestos fibers in brake pad production. The process involves crushing, grinding, and sieving coconut fiber into a powder, mixing it with steel dust, carbon black, and epoxy resin, filling a mould, adding hardener, and pressing and curing samples at 250 °C. The produce is tested for mechanical properties, with optimal brake pad properties achieved using a 100μm sieve grade, enhancing interfacial bonding between resin and coconut shell particles. The hardness, compressive strength, ash content, specific gravity, wear rate, and water absorption values were found to be 258, 113 N/mm2, 40%, 1.91, 3.23 mg/m, and 0.63%. The study found that coconut shell has qualities similar to those needed for brake pad material and asbestos replacement in brake pad production. Coconut shell, with its 100μm particle size, has the potential to replace asbestos-based brake pad manufacturing, reducing harmful components and environmental impact.

Production of Biocalcium from Fermented Fish Bone Residue for Fish Emulsion Sausage Fortification.

Fermented fish bone residue (FFBR) is an underused by-product of the industrial-scale production of fermented fish sauce. Subjecting FFBR to proper alkaline treatment can transform FFBR into biocalcium, which can be added to fish emulsion sausage (FES) to increase its calcium content. This study comprised two experiments. First, we aimed to find the most suitable alkaline treatment conditions for preparing biocalcium from FFBR. Alkaline treatments combining three sodium hydroxide (NaOH) concentrations (0%, 3%, and 6%) and three soaking times (0, 1, and 2 h) were tested. Quality parameters of alkaline-treated biocalcium (crude protein, crude fat, ash content, calcium, phosphorus, crude fiber, salt content, CIE color values, morphology of biocalcium particles, and the intensity of the fermented fish smell) were assessed. Second, we fortified FES with the properly treated biocalcium (0, 12, 24, or 36 g) and evaluated the sausage's calcium, phosphorus, crude fiber, salt content, pH, CIE color values, texture profile analysis (TPA), emulsion stability, and sensory criteria. It was found that treatment with 3% or 6% NaOH produced better crude protein, ash content, calcium, and CIE color value results than no alkaline treatment. These two NaOH concentrations effectively lowered the salt content and the intensity of the fermented fish smell. However, 3% and 6% NaOH produced similar results. A soaking time of 1 h or 2 h produced better results than no soaking in terms of crude protein, crude fat, ash content, calcium, phosphorus, CIE color values, and the intensity of fermented fish smell. However, 1 h and 2 h produced similar results. It is concluded that 3% NaOH and soaking for 1 h would be the most suitable alkaline treatment to prepare biocalcium from FFBR. Fortifying FES with biocalcium from FFBR increased the calcium and phosphorus contents but slightly reduced TPA. The other FES quality parameters were unaffected by biocalcium fortification.

Biochemical and physicochemical properties of shrimp (Pandalus borealis) compounds after compact filter press process

AbstractBackgroundMost of the shrimp side streams are discarded due to the lack of appropriate processing techniques/methodology for their utilization, which is not only a loss of potentially valuable compounds, but also leads to environmental pollution. The study aimed to employ a mechanical filter press to separate the liquid called press juice (PJ) and the solid named press cake (PC) fraction from shrimp head and shell (H&S).ResultsThe proximate composition was performed, including amino acids analysis, protein content, fatty acids, and the main volatile compounds. In the whole shrimp (WS), the average values of protein, lipid, dry matter, and ash content were recorded at 14.7%, 2.9%, 21.1%, and 4.8%, respectively. The protein percentage reached 10.1% in H&S, indicating considerable amount of protein leftover in the shrimp side streams (p < 0.05). The major PUFAs in WSs' sample were Eicosapentaenoic acid (EPA) (8.8%) and Docosahexaenoic acid (DHA) (7.8%). Furthermore, the values of EPA and DHA a showed nearly two‐folded increase after peeling and filter‐pressing, PC sample. Total amino acids in the WS, H&S, PJ, and PC samples were found to be 94.6, 67.7, 22.2, and 76.6 mg/g, respectively. From the nutritional point of view, non‐essential amino acids represented higher values (13.2%–56.9%) compared to essential amino acids (9.0%–37.6%). The major components of 5′‐neucleoitides in WS sample were in order of guanosine‐5′‐diphosphate (GDP) ≫ hypoxanthine (HYP) > inosine‐5′‐monophosphate (IMP) ≫ adenosine‐5′‐monophosphate (AMP) > adenosine‐5′‐diphosphate (ADP) with values of 684.4, 293.6, 201.4, 25.6 and 16.2 μg/g sample, while no inosine (INO), guanosine‐5′‐monophosphate (GMP), and guanosine‐5′‐triphosphate (GTP) were detected. Equivalent umami concentration (g MSC/100 g) was recorded as 0.63, 0.07 for WS and H&S samples and 0.015 for PJ sample, which indicates a significant drop from the shrimp raw material toward the side streams. Most volatile compounds belonged to alkenes followed by alkanes groups.ConclusionThis work showed the possibility to employ the filter press machine to obtain PJ and PC from shrimp H&S, after peeling processing. The fractions present an interesting nutritional composition and value.

The Making of Biobriquettes with Carbonization Method by Utilizing Sludge Cake and Wood dust from the Pulp Industry

Sludge cake as a solid waste that is rarely used from residual sludge from Waste Water Treatment Plants is one source of biomass from the pulp and paper industry which has the potential to be used as renewable energy. Analysis of biobriquette characteristics includes: moisture content, ash content, volatile matter, bound carbon, and calorific value. The results of this research show that the best combination of biobriquettes is biobriquettes with a composition of 40% sludge cake, 50% Eucalyptus pellita wood dust, and 10% black liquor adhesive which has a moisture content of 2.12%, ash content of 19.33%, volatile matter 28 .99%, calorific value of 4915.69 kJ/gr, and fixed carbon content of 49.63%.

Analysis and Characterization of Four Selected Sri Lankan Seed Oils for the Potential Applications in Cosmetics and Dietary Supplements

As a tropical country, Sri Lanka has a wide variety of oil-bearing seeds explicitly used in Ayurvedic and indigenous medicine. Plant seed oils offer an exciting avenue for the use in cosmetic and dietary supplements due to their fatty acid composition and other non-polar constituents specially found in unsaponifiable fraction. This study aimed to characterize plant seed oils by determining Fatty Acids (FA) composition, constituents in unsaponifiable matter, and other physical properties. Mesua ferrea L. (Na), Crotalaria juncea L. (Hana), Ricinus communis L. (Thel edaru), and Bauhinia acuminata L. (Koboleela) seeds having some medicinal values were selected. The oil was extracted using soxhlet extraction method with Hexane. Moisture and ash content, Acid Value (AV), Iodine value (IV), and Smoke Point were also determined. Prepared Fatty Acid Methyl Esters (FAME) and unsaponifiable matter were analyzed using GC-MS. Thermogravimetric Analysis (TGA) was performed to access the thermal stability. M. ferrea obtained the highest oil yield of 63.87% while others lay within the range of 28.59-29.94%. Smoke point values of these oils varied from 179.0±10.5oC to 241.5±6.2o C. AVs lay between 4.62±1.18-49.64±2.92 mgKOH/g range. IVs ranged from 6.82±0.89 to 16.82±0.45 gI2/100g. Ash content values varied from 1.42±0.33% to 3.69±0.29% while the moisture content ranged from 0.69±0.09% to 4.46±0.51%. The yield of unsaponifable matter of these four seed oils ranged from 0.7024±0.0001% to 1.5864±0.0001%. All except M. ferrea oil exhibited higher levels of unsaturated fatty acids than saturated fatty acids. In contrary M. ferrea contained almost equal amounts of UFAs and SFAs. The most abundant FA constituents of all the oils were long-chain FAs like Oleic, Linoleic, and α-Linolenic Acid. γ- Sitosterol was the most dominant compound in unsaponifiable fraction in most of the seed oils which indicate their potential use in dietary supplements. The high level of Squalene found in R. communis shows its applicability in the cosmetic industry as a moisturizing agent. This analysis found that all 4 oils have the potential to use in dietary supplements and cosmetics. 
 Keywords: Seed oils, Unsaponifiable matter, Fatty acids, Cosmetics and dietary supplements

Physico-chemical Characteristics of Biochar Briquettes Blend of Goat Manure Charcoal, Saboak Shells and Rice Husk

The study aimed to determine the effect of goat manure charcoal mixture, saboak shell and rice husk on the physico-chemical characteristics of biocharcoal briquettes. The completely randomized design with 4 treatments and 4 replicates was applied. Those treatments were P1 = 25% goat manure + 75% saboak shell without rice husk, P2 = 25% goat manure + 50% saboak shell + 25% rice husk, P3 = 25% goat manure + 25% saboak shell + 50% rice husk, P4 = 25% goat manure + 75% rice husk without saboak shell. Variables measured: yield, density, moisture content, ash content, volatile matter, fixed carbon and calorific value. The average data obtained were: yield 58.94%; density 0.65 g/cm3; moisture 2.42%; ash 27.41%; volatile matter 26.58%; fixed carbon 43.59%. and calorific value 4086.7 cal/ g; Statistical analysis showed that treatment had a very significant effect (P<0.01) on ash content and fixed carbon; significant effect (P<0.05) on moisture content and calorific value; and not significant (P>0.05) on yield, density and volatile matter. It was concluded that increasing the proportion of rice husk charcoal in the mixture with goat manure and saboak shell produced biochar briquettes with characteristics decreased of moisture content, fixed carbon and calorific value, increased of ash content while yield, density and volatile matter tended to be the same.

Optimization and characterization of hybrid bio-briquettes produced from the mixture of sawdust, sugarcane bagasse, and paddy straw.

Biomass briquetting is a viable densification technique that converts waste biomass materials into useful products and alternative energy. This work explores the characteristics and optimization of hybrid bio-briquette production by combining crop residues (paddy straw) and solid biomass materials (sawdust and sugarcane bagasse). A total number of 20 briquettes were fabricated with three input factors: sawdust (SD), sugarcane bagasse (SB), and paddy straw (PS) based on the faced-centered central composite design (FCCCD) approach in the laboratory to investigate the calorific value (CV) and ash content (AC). The bomb calorimeter technique was used to evaluate the briquette's calorific value and ash content. The proposed work focused on optimizing the briquette input parameters (SD, SB, and PS) and output responses (CV and AC) using analysis of variance (ANOVA) and response surface methodology (RSM) and hybrid artificial neural network-integrated with multi-objective genetic algorithms (ANN-MOGA). This study shows that the MOGA-ANN-based model results in the best value of CV (17.07 MJ/kg) and AC (1.95%) with optimal input parameters SD (39.99 g), SB (29.02 g), and PS (69.02 g). The optimal results observed from the MOGA-ANN model have also been validated experimentally. The Fourier transform infrared (FTIR) spectroscopy investigation reveals that biomass briquettes are the sustainable and environment-friendly option of fossil fuels for power generation and indoor cooking. The study suggests a strategy for minimizing agro-waste, which may be converted into future fuel in the form of briquettes.

Enhancing sustainability: co-pyrolysis of date palm branches and wastewater microalgae for tailored biochar production

The use of waste products in different applications contains prime importance in today’s research and industry. Researchers are working on producing innovative technologies and processes to utilize waste and produce valuable products for different applications. Microalgae-derived char contains low aromaticity and heating values with relatively higher nitrogen content than lignocellulosic char. This study presents the use of waste from date palm branches and wastewater-derived microalgae through co-pyrolysis to produce char of improved properties. Two batches of experiments were conducted (a) single-step pyrolysis (SSP) and (b) two-step pyrolysis, in the range of highest treatment temperature of 400–600 °C. Single-step pyrolysed char showed lower aromaticity, higher yield, ash content and heating values of the char than two-step pyrolysed char. Similarly, ignition temperature and activation energy were higher during combustion by single-step pyrolysed char than two-step char. Economic analysis also showed slightly higher prices for single-step pyrolysed char. Hence, two-step pyrolysed char is suitable for energy applications, whereas low-temperature processing (400–500 °C) will result in optimum properties in terms of yield and heating values.

Rapid quantitative analysis of petroleum coke properties by laser-induced breakdown spectroscopy combined with random forest based on a variable selection strategy.

Driven by the "double carbon" strategy, petroleum coke short-term demand is growing rapidly as a negative electrode material for artificial graphite. The analysis of petroleum coke physicochemical properties has always been an important part of its research, encompassing significant indicators such as ash content, volatile matter and calorific value. A strategy based on laser-induced breakdown spectroscopy (LIBS) in combination with chemometrics is proposed to realize the rapid and accurate quantification of the above properties. LIBS spectra of 46 petroleum coke samples were collected, and an original random forest (RF) calibration model was constructed by optimizing the pretreatment parameters. The RF calibration model was further optimized based on variable importance measures (VIM) and variable importance in projection (VIP) methods. After variable selection, the elemental spectral lines related to ash content, volatile matter and calorific value modeling were screened out, thus initially exploring the correlation between these properties and elements. Under the optimized spectral pretreatment method, VI threshold and model parameters, the mean relative error (MREP) of the prediction set of ash content, volatile matter and calorific value were 0.0881, 0.0527 and 0.006, the root mean square error (RMSEP) of the prediction set of ash content, volatile matter and calorific value were 0.0471%, 0.6178% and 0.2697 MJ kg-1, respectively, and the determination coefficient (RP2) of the prediction set was 0.9187, 0.9820 and 0.9510, respectively. The combination of LIBS technology and chemometric methods can provide powerful technical means for the analysis and evaluation of the physicochemical properties of petroleum coke.

Впровадження технології трамбування на діючих коксових батареях

DOI: 10.31081/1681-309X-2024-0-2-14-28 Specialty 161. U.D.C. 662.74.2 IMPLEMENTATION OF TAMPING TECHNOLOGY AT OPERATING COKE OVEN BATTERIES © S.O. Kravchenko, Ph.D. in Technical Sciences (STATE ENTERPRISE "STATE INSTITUTE FOR DESIGNING ENTERPRISES OF COKE OVEN AND BY-PRODUCT PLANTS'' (SE "GIPROKOKS''), 61002, 60 Sumska str., Kharkiv, Ukraine), D.V. Miroshnychenko, Doctor of Technical Sciences (National Technical University "Kharkiv Polytechnic Institute", 2, Kyrpychova str., Kharkiv, 61002, Ukraine), V.V. Koval, Ph.D. in Technical Sciences (STATE ENTERPRISE “UKRAINIAN STATE RESEARCH INSTITUTE FOR CARBOCHEMISTRY (UKHIN)”, 7 Vesnina str., Kharkiv, 61023, Ukraine), M.O. Solovyov, Ph.D. in Technical Sciences, S.Y. Abdullin, S.G. Grankin (SE "GIPROKOKS'') The article is devoted to verification of ensuring the appropriate economy and efficiency of coke production while reducing the level of consumption of scarce raw materials in order to optimise production in the current conditions of a coke-chemical enterprise. It is shown that the production of blast furnace coke using the technology of tamping the coal charge allows the use of a large amount of cheap gas coal without reducing the quality of the resulting blast furnace coke. However, despite the fact that this coking technology has been in use for a long time, the literature data on the impact of increasing the loading density on coke quality parameters is insufficient, contradictory and outdated. This article describes the main technical solutions for the conversion of an existing coke oven battery from the bulk coking chamber loading technology to the tamped coal cake loading technology and presents the results for the reconstructed coke oven battery. This project was developed and implemented by SE “GIPROKOKS” and HuDe. The economic and technological indicators of coke quality as a result of the conversion of the existing coke oven battery to the technology of loading a tamped coal cake were considered and compared with the parameters of its operation using the technology of bulk loading of coking chambers. It is shown that during the control period of observations (19 months) of the enterprise's operation, the mechanical strength of M25 coke increased on average from 85.2 to 87.4 %; post-reaction strength CSR – from 48.9 to 53.9 %; at the same time, the abrasion index M10 decreased from 8.0 to 5.9 %, and the reactivity CRI – from 38.0 to 37.2 %, respectively, when working using the tamping technology compared to the bulk method. In addition, the coke obtained by using the charge tamping method is characterised by lower values of ash and total sulphur content. Keywords: coke oven battery, charging, bulk (gravity) method, tamping technology, coal cake, coke properties. Corresponding author S.O. Kravchenko, e-mail: sa_kravchenko@giprokoks.com

Transformation of peat deposits and carbon accumulation in post-pyrogenic raised bogs within the taiga zone of West Siberia

The aim of the study was to assess of the transformation of the hydrologic and physical properties of peat deposits and peat accumulation rates in the post-pyrogenic sites of drained fens in the taiga zone of West Siberia. Location and time of the study. Field studies were conducted in 2022 on the Bakchar fen (drained for forestry, seven plots) and Ust-Bakchar fen (drained for peat extraction, three plots) located in the Tomsk region. Methods. Peat sampling was carried out from two boreholes at each plot in the hollow and the hummock. The sampling increment was 5 cm; the total depth was 45–90 cm. Peat samples were taken at nine subsites by the envelope method on each plot in 0–30 cm layer by 10 cm increment for water content determination in laboratory. Laboratory study of peat characteristics was carried out using the following methods: water and ash content measurements (GOST 11306-2013, GOST 11306-2013), estimation of peat decomposition and humification degree, botanical composition (GOST 28245-89), as well as measuring peat bulk density. Carbon stocks in the upper layer of peat deposits was estimated using the values of peat ash content and density. Results. The peat deposit of the upper layers was formed mainly by sphagnum peat with Sphagnum fuscum plant residues predominating. The differences between hollows and hummocks in their peat properties were manifested to a depth of 5–15 cm from the surface of depressions. The burnout of the hollows led to the changes of all peat properties to a depth of 10–15 cm: the changes were more pronounced in ash content, which was 1.5–9 times higher in the 0–5 cm layer as compared with the unburned site. The changes in peat properties on positive relief forms, i.e. moss hummocks, was less evident in the upper 0–5 cm layer, but reached a greater depth of 30 cm. The change was revealed mainly as an increase in peat ash content due to the migration of ash elements from the surface of burnt hollows and as an increase in bulk density due to subsidence of moss hummocks with the died-off sphagnum moss. Although the average water content in postpyrogenic and unburned sites was the same, amounting to 90–91% in the 0–30 cm layer, some difference was observed between the microrelief forms. The post-pyrogenic site in the Bakchar fen was characterized by water content decrease in hollows and hummocks, the maximum values being observed at an altitude near the average surface. In the Ust-Bakchar fen, water content was found to decrease from hollows to hummocks. In the Bakchar fen, 30 years after the fire peat accumulation occurred only on positive microrelief forms, where the 35 cm thick layer formed after the fire. Taking into account the microrelief heterogeneity, carbon accumulation over the post-fire period was estimated as 1.9 kg C/m2 or 60 g C/m2 per year. Peat accumulation seemed much slower in the Ust-Bakchar fen and was apparently absent on most of the surface. The average rate was estimated as 7 g C/m2 per year. Conclusions. The study found fen hollows to be most prone to burnout. The consequences of the fire manifest themselves in the drying of the upper layer of the peat deposit, thus preventing intensive overgrowth by sphagnum mosses 6–8 years after the fire. At the drained for forestry site in the Bakchar fen, 30 years after the fire the peat accumulation rate on moss hummocks was comparable to the rate in the unburned areas.

The Influence of Fuel Composition on the Operating Characteristics of the Steam Boiler

The paper presents the impact of using high ash content and poor heating value hard coal as fuel for a steam boiler. As expected, the poor quality of the fuel has an important impact on the efficiency of the steam boiler, reducing it by almost 4%. From that also results an increase in specific fuel consumption of the boiler. The mechanism by which these negative results are reached are mainly the increase in losses through combustion gases by nearly 2% and the heat of the evacuated slag which almost doubles.

Characterisation of biochar from various carbon sources

The purpose of this study was to characterise biochar produced from various carbon sources. This study was conducted using a Nested De sign with three replications. Three carbon sources, rice husk (RH), corn co bs (CC), and bagasse sugarcane (BS) were pyrolysed for 2 hours at temper atures of 400, 500 and 600°C. The three types of biochar were then analyse d on their moisture content, ash content, fixed carbon content, volatile matt er, calorific value, particle size and elemental analysis results. The results of this study were that the temperature of pyrolysis at 600 °C can optimally produce biochar with the lowest moisture content, ash content and volatile matter value, and highest fixed carbon and calorific values. The particle siz e analysis shows that biochar produced using this optimum condition has the smallest average particle size distribution. The elemental analysis condu cted through Scanning electron microscopy with energy dispersive X-ray s pectroscopy (SEM-EDX) shows various elements in each biochar produce d from the three different carbon sources.