Kiln Units Research Articles

Terje Aven Availability Model Application to the N-1 System with One Unit of Backup Towing Motor Components for Kiln Machine Preventive Maintenance

The kiln machine is one of the pieces of machinery used to produce granite tiles. One of its many crucial components is the towing motor. The production process requires a high-performance and easily accessible kiln unit because it lasts for 24 hours. As a result, there will be less downtime since the extra towing motor can take the place of the damaged one. The Terje Aven availability model calculates the number of towing motor reserves. The availability of kiln equipment has not yet achieved its full potential because the company currently has six backup towing motors.

Toxicological profile and potential health concerns through metals and trace elements exposure in brick kiln workers from Lahore, Pakistan.

This study examined levels of lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), and arsenic (As) in blood, hair, and nails of 18 brick kiln workers from three brick kiln units located around a metropolitan city, Lahore, Pakistan. All the trace elements except Hg and As were detected in the studied matrices of Brick kiln workers. In general, brick kiln workers reflect the highest concentration of Pb, followed by Cd, Cr, and Cu. Of the pollutants analyzed, Pb has the highest mean (min-max) concentrations at 0.35 (0.09-0.65) in blood(μg/mL), 0.34 (0.14-0.71) in hairs(μg/g), and 0.44 (0.32-0.59) in nails(μg/g) of brick kiln workers. Following Pb, the trend was Cd 0.17 (0.10-0.24), Cu 0.11(0.03-0.27), and Cr 0.07 (0.04-0.08) in blood(μg/mL), followed by Cr 0.11(0.05-0.20), Cd 0.09 (0.03-0.13), and Cu 0.08 (0.04-0.16) in hairs(μg/g) and Cu 0.16 (0.05-0.36), Cd 0.13 (0.11-0.17), and Cr 0.10 (0.05-0.14) in nails(μg/g) respectively. Relatively higher concentrations of metals and other trace elements in blood depicts recent dietary exposure. The difference of trace elements except Pb was non-significant (P > 0.05) among studied matrices of workers as well as between Zigzag and traditional exhaust-based brick kilns. The concentrations of Pb, Cd and Cr in blood of brick kilns workers are higher than the values reported to cause health problems in human populations. It is concluded that chronic exposure to metals and other trace elements may pose some serious health risks to brick kiln workers which needs to be addressed immediately to avoid future worst-case scenarios.

Sustainability Assessment Of Carbon Dioxide Emission Reduction From Energy Use In Cement Production Via Life Cycle Assessment And Ahp

The cement industry in supporting sustainable development is faced with the challenge of reducing energy consumption, natural resources and emissions generated from its production activities. PT X is one of the cement industries in Indonesia that has a production design capacity of 2.6 million tons/year. PT X's cement production activities use several fossil fuel energy sources and alternative fuels that can produce carbon dioxide emissions that are wasted into the environment. This study aims to identify process units that produce significant impacts to determine alternative environmental improvement scenarios. The method used is Life Cycle Assessment (LCA) as a tool for calculating potential environmental impacts, and AHP as an alternative selection of environmental improvement program scenarios. The scope of the LCA study carried out with the scope of "Cradle to Gate" includes the stages of the raw material extraction process, the production process to the distribution of cement. The resulting potential environmental impact is a total Global Warming Potential (GWP) of 0.20543 tons CO2 eq/ton. The largest potential impact comes from the kiln unit of 0.20221 tons CO2 eq/ton or an impact contribution of 98.43%. Based on the environmental impacts generated, there are 4 alternative programs that can be used to reduce the environmental impacts generated. The selection of alternative program scenarios is based on 3 criteria based on 3 types of respondents. Alternatif program yang memiliki nilai prioritas tertinggi yaitu alternatif program 1 dengan sebesar 35,5%, 38,1%, dan 23,4%.

Eulerian CFD simulation of biomass thermal conversion in an indirect slow pyrolysis rotary kiln unit to produce biochar from recycled waste wood

Producing energy and higher value bio-products from waste wood recycled from construction and demolition (C&D) debris has been proposed as an economically viable opportunity in the biomass and bioenergy sectors. However, several challenges associated with the thermal conversion processes remain to be solved. This study introduces a 3D numerical simulation to study thermal conversion of wood chips. Combined biomass combustor, and indirect pyrolysis unit is used to create a self-sustainable biomass unit which does not rely on fossil fuel. Multizone heat distribution in the rotary kiln unit is investigated by employing CFD, an analytical algorithm and measurement tools in different zones of the equipment. A multizone heat transfer concept, the overall yield rate of biochar, thermochemical conversion of the bed, the volume shrinkage in the wood chips during the pyrolysis process, as well as biomass volatile and tar composition, and finally the potential of energy savings is widely investigated. CFD results and experimental evidence confirm that at least 31 % energy saving in drying zone can be achievable if drying and pyrolysis zone are separated in the indirect slow pyrolysis rotary kiln unit. The quality of biochar improved by 21 % increase in fixed carbon content and tar condensation is controlled.

Analisis Kesehatan dan keselamatan kerja (K3) dengan metode Hazard Identification, Risk Assesment and Risk Control (HIRARC) pada unit Kiln PT. Semen Indonesia (Persero) Tbk. Pabrik Tuban

Occupational safety and health is a program created in an effort to prevent work accidents and occupational diseases. The goal is to create a comfortable, safe, and healthy workplace so that it can reduce the risk of work accidents as much as possible. The method used in reducing the risk of work accidents at PT. Semen Indonesia (Persero) Tbk. The Tuban factory, namely the HIRARAC (Hazard Identification, Risk Assessment, and Control) method, After conducting the research, there are several sources of danger that exist in the kiln unit, namely operating the kiln when the percentage of carbon dioxide is high, replacing burnerheads, operating belt conveyors, repairing electrical panels, checking kiln shell inlets, breaking dead-end production lines, and adding chemical mixtures. Then they carried out risk management efforts to reduce the risk of workplace accidents. Risk control measures are guided by the control hierarchy, namely by means of elimination, substitution, design, administration, and PPE. Risk control that has been carried out is by installing and complying with safety lines, barricades, safety signs, and using PPE, including safety helmets, safety shoes, hand gloves, a full body harness, safety goggles, fire-resistant clothing (nomex), and respirators.

СЖИГАНИЕ RDF-ТОПЛИВА С ИСПОЛЬЗОВАНИЕ КИСЛОРОДНОГО ДУТЬЯ

The cement industry has unique opportunities to address the issues of utilization of manmade raw materials and municipal waste. The problem of using alternative fuels in the technological process of cement production is usually due to their low calorie content. The above calculations show the possibility of using RDF fuel as part of a mixed fuel when it is burned under conditions of an increased oxygen content in the air. Reducing the volume of combustion products increases the temperature of the torch, which increases the productivity of the cement rotary kiln, mixed fuel can be used in both low – and high-temperature zones of cement kiln units with an optimal ratio of components. There are restrictions on increasing the concentration of oxygen in the air, due to a decrease in the actual combustion temperature of the fuel due to the reverse reactions of the decomposition of combustion products and violations of the high-speed modes of operation of suspension heat exchangers. In addition, an increase in oxygen in the air significantly reduces the thermal efficiency of the clinker cooler as a result of the increase in excess air volumes. The use of RDF fuel in the optimal ratio allows replacing up to 42 % of natural gas.

IMPACT OF MECHANISATION ON SOCIO-ECONOMIC CONDITION OF DONKEY GUARDIANS OF DISTRICT SANGLI, MAHARASHTRA, INDIA

The state of Maharashtra is the leading bricks producing state in India. The usual brick making season is from November/December to May/June. Raw bricks moulding work is done manually in the majority of brick kiln units and transport of these raw bricks from the place where they are moulded to the furnace on the back of donkeys by their owners/guardians. Donkeys and their guardians work in harsh environment of brick kiln which affect the health of animals as well as their guardians and hence suffer from serious health issues. Overloading on donkeys with raw bricks is the major factor for health deterioration of animals and donkey guardians have to work for longer hours with animals in harsh conditions. Hauling heavy loads on donkeys back is directly associated with higher income being earned by their guardian’s, which is an economic requirement. This review emphasises on the change in lives of donkey guardians who have begun to use tractors instead of donkeys for hauling the raw bricks resulting in more income in less time. Study found positive impact on the socio-economic status of donkey guardians and such mechanisation process may lead to sustainable change in lives of donkey guardians and this will also save the sentient donkeys from the hardships of brick-kiln work.

Energy and Exergy Analysis on the Rotary Kiln Unit of RKC-2 PT. Semen Gresik – Tuban Plant

Cement industry is an industry that intensively uses energy in the process. One of the main units in a cement plant that consumes the most energy is the rotary kiln. Rotary kiln is used for calcination process of cement raw material into clinker. It operates at 900-1450°C. It obtains energy from coal combustion process. Energy conservation in rotary kiln can be used to optimize production costs. Energy conservation can be carried out through energy identification. One method of energy identification is through energy and exergy analysis. In this study, energy and exergy analysis was carried out at the rotary kiln unit of RKC-2 PT. Semen Gresik - Tuban Plant. The analysis was carried out based on the calculation of the mass balance, energy balance, enthalpy balance, entropy balance and exergy balance. These calculations are used to obtain energy efficiency, exergy efficiency and irreversibility. Based on the research results, the energy efficiency, exergy efficiency, and irreversibility were 69,2%; 50,48% and 49,52% respectively.

Life cycle assessment (LCA) of portland composite cement (PCC) 50 kg papercraft bag at PT. Semen Padang

PT. Semen Padang produces several cement types, including PCC, with a total production of up to 6,568,354 tons in 2018. PCC production reached 54% of the total, where the size of 50 kg bag dominates the production with 93%, and the use of papercraft bags as the cement packaging is 78.39%. This research aims to analyze the environmental impacts of the production of 1 ton of PCC 50 kg paper craft bag using the LCA method. The gate-to-gate approach applies as the boundary, ranging from raw mill till packing unit. The impact assessment method uses IMPACT 2002+ to assess the environmental impact of the production. The result shows that the highest environmental impacts are global warming, non-renewable energy, and respiratory inorganics, with the value amounted to 0.10884252 Pt. The process of calcination and coal used in the kiln, packaging transport by diesel-powered trucks, and electricity use is the main contributor to the impact value. In order to improve the PCC production, it is recommended to have an alternative fuel on the kiln unit using rice husks or Mischantus giganteus.

Heat exchange simulation in energy zones of a rotarykiln with change of heat resistance of the body

The object of research is high-temperature thermal units – rotary kilns. Rotary kilns are used in various industries. The specified equipment has high energy consumption, which is due to the operating conditions of the kiln units in compliance with a number of technological requirements for thermal conditions. At the same time, the problem of high energy intensity is aggravated by the low level of useful energy resources. One of the most problematic places is the thermal and operational characteristics of rotary kilns, as well as the use of lining with increased thermal resistance.Physical and mathematical models are used. It is proposed to calculate a rotary kiln for the production of cement with a size of 5x185 m and a capacity of 75 t/h. A mathematical model is obtained for computer simulation of technological processes in rotary cement kilns. The possibilities of reducing fuel consumption by increasing the thermal resistance of the lining of a rotary kiln are considered. The most energy-intensive zones are determined and the effect on the thermal efficiency of using additional thermal insulation in various energy zones in a rotary kiln is analyzed. Calculations and the results of a numerical experiment are presented. The most rational areas for the use of lining with additional thermal insulation are determined. It is found that with the integrated application of the proposed method, fuel consumption in a thermal unit can be reduced by 9 %. And an increase in the thermal resistance of the lining installed in high temperature zones will increase the energy efficiency of the thermal unit. A significant advantage of this method is the fact that an increase in kiln productivity does not require additional fuel consumption, an increase in temperature, or an increase in the enthalpy of combustion products.In the future, it is planned to study the mechanism for establishing a heat-insulating layer in the refractories of the lining, determining their optimal thermal efficiency and stress-strain state to eliminate the possibility of destruction. As well as determining the optimal structural form of the refractory and the cell with thermal insulation.

Exploring the musculoskeletal problems and associated risk-factors among brick kiln workers

Purpose Prolonged working in repetitive and awkward postures can result in musculoskeletal disorders among workers involved in labour-intensive jobs like those of brick kiln workers. Unlike other labour-intensive sectors, workers in this particular sector have a lack of awareness about musculoskeletal problems. Therefore, the purpose of this paper is to explore musculoskeletal issues and associated risk-factors among brick kiln workers. Design/methodology/approach A questionnaire survey was conducted among 217 male and 111 female workers aged between 17 and 53 years. They were employed in traditional brick kiln units situated in Rajasthan, India. Postures were analysed by Rapid Upper Limb Assessment and Rapid Entire Body Assessment methods. Binary logistic regression was used to find the association between musculoskeletal problems and risk-factors. Findings For the mould evacuating task, wrist (76.2 per cent) and lower back (56 per cent) issues were the most frequently reported musculoskeletal problems, while in spading task, lower back (62.4 per cent) and shoulder (57.7 per cent) problems were prominent. Musculoskeletal symptoms in one or more body regions were associated with personal and work-related factors including the type of task and experience. Research limitations/implications Kiln workers are exposed to high musculoskeletal and postural risks, particularly in spading and mould filling tasks. To reduce these risks, ergonomic interventions are needed. Originality/value It is recognised that the musculoskeletal health of brick kiln workers is a cause for concern. The present study provides the evidence of the prevalence of musculoskeletal symptoms experienced by brick kiln workers and the association of symptoms with various risk-factors, which has not been addressed in previous studies.

Evaluation of surface roughness and wettability of heat-treated, fast-growing tropical wood species sengon (Paraserianthes falcataria (L.) I.C.Nielsen), jabon (Anthocephalus cadamba (Roxb.) Miq), and acacia (Acacia mangium Willd.)

ABSTRACTSengon, jabon, and acacia are fast-growing tropical wood species that are important for several wood industries in Indonesia. The purpose of this research was to evaluate the surface roughness and wettability of some heat-treated, fast-growing Indonesian wood species. Surface roughness was evaluated using the mean arithmetic deviation of the profile (Ra), whereas wettability was determined by measuring the contact angle method. The wood was subjected to heat treatment at 120, 150, or 180°C for 2 or 6 h using a small kiln unit. The heat treatment modification reduced the moisture content, wood density, and surface roughness and increased the wettability properties of all wood species. Jabon wood was the smoothest, followed by acacia and sengon, whereas jabon had the lowest wettability, followed by acacia and sengon. Wood anatomy has influences on those properties tested. Heat treatment did not affect surface quality but revealed a significant difference in wettability properties.

Carbonation of Steel Slag: Testing of the Wet Route in a Pilot-scale Reactor

This work reports the first results of an on-going activity aimed at the scale up of the wet-route carbonation of steel slag for storing CO2 and generating a product with valorization potential. Two batches of Basic Oxygen Furnace slag (BOF1 and BOF2) collected at different times from a steelmaking plant downstream iron recovery were used to perform the tests in a pilot-scale rotary kiln unit part of ENEA's research infrastructure. The tests were carried out at ambient (25°C- 37°C) and enhanced temperature (45°C-53°C), under a 40-47% CO2 flow, at atmospheric pressure for a reaction time of 30min. In each experiment around 1000-1500g of BOF slag was employed. The residues were humidified in order to achieve a liquid to solid ratio of 0.17 l/kg. This value was selected on the basis of the results of preliminary lab-scale static and dynamic experiments that are also presented in this paper. The product collected at the end of each test was cured at controlled conditions (T=25°C e RH=100%) for 28 days and then characterized in terms of particle size, CO2 uptake and environmental behavior. The mean diameter (D50) of the obtained product was around 1mm for the tests performed at room temperature and slightly lower for the test performed at 50°C, i.e. around twice the size of the starting material. The CO2 uptake measured for samples collected immediately after the tests was quite similar (4-6% wt.), whereas after curing a 50% increase was observed for all BOF1 slag samples, while only a slight increase was observed for BOF2 slag. These results are significantly higher than the ones of the lab-scale tests. The leaching behavior of the product appeared also to be significantly affected by the treatment performed in the pilot plant.

Exergetic assessment of a rotary kiln for clinker production in cement industry

Cement industry is one of the most energy consuming sectors in the world. Through a cement plant, rotary kiln is the most energy intensive section that consumes the highest portion of the total energy, so it is getting very substantial to perform energy and exergy analyses for determining possible energy–saving options. In this study, thermodynamic assessment of the rotary kiln unit of a cement plant is carried. For the analysis, mass, energy and exergy balances of the rotary kiln are constituted and using actual plant data the performances of the rotary kiln are identified. The rotary kiln clinker capacity is 79 tons per hour. The energy and exergy efficiency of the unit is found to be 68% and 58.6%, respectively. At the end of the study, the results are compared with the other studies concerning with the same matter of different plants and available heat recovery possibilities are discussed.

Cancer risk evaluation of brick kiln workers exposed to dust bound PAHs in Punjab province (Pakistan)

Principal objective of this study was to evaluate the health risks of brick kiln workers to dust bound PAHs exposure in Punjab province (Pakistan). To this aim, surface dust samples were collected from brick kiln units located in Chung Khurd (Lahore city), Gujranwala city and Sohra village (in the vicinity of Gujranwala). The highest ΣPAH levels were measured in the dust samples collected in Sohdra village (mean 2578ngg−1 d.w., range 302–6757ngg−1 d.w.) followed by Gujranwala city (mean 957, range 16.1–1963ngg−1 d.w.) and Chung Khurd (mean 882, range 692–1007ngg−1 d.w.). Source identification using diagnostic ratios and principal component analysis identified coal and wood combustion as the major PAHs sources. The cancer risk model (CR-Model 1) and the Incremental Lifetime Cancer Risk model (ILCR-Model 2) were used to evaluate the cancer risk assessment via ingestion, inhalation and dermal contact pathways. Both models suggested that brick kiln workers (including adults and children) were exposed to high-potential carcinogenic risk via both ingestion and dermal contact pathways during the brick making process. This study also emphasizes the need for pollution control in the brick kiln industry of Pakistan.

Biomass fuel burning and its implications: Deforestation and greenhouse gases emissions in Pakistan

Pakistan is facing problem of deforestation. Pakistan lost 14.7% of its forest habitat between 1990 and 2005 interval. This paper assesses the present forest wood consumption rate by 6000 brick kilns established in the country and its implications in terms of deforestation and emission of greenhouse gases. Information regarding consumption of forest wood by the brick kilns was collected during a manual survey of 180 brick kiln units conducted in eighteen provincial divisions of country. Considering annual emission contributions of three primary GHGs i.e., CO 2, CH 4 and N 2O, due to burning of forest wood in brick kiln units in Pakistan and using IPCC recommended GWP indices, the combined CO 2-equivalent has been estimated to be 533019 t y −1.

Emission of Greenhouse Gases (GHGs) from Burning of Biomass in Brick Kilns

Burning of biomass fuel is an important source of emission of greenhouse gases in the environment. Due to anthropogenic activities, concentrations of greenhouse gases are increasing, having a direct effect on the world's climate, which poses serious threat for mankind. In the present study, emission of greenhouse gases has been attributed to the burning of biomass fuel, i.e., fire wood consumption in the brick kilns located in eight provincial divisions of Punjab, Pakistan. Analysis of collected data concludes that burning of forest wood in 4,000 brick kiln units results release of 525,440 tonne per year of combined CO2 equivalent of greenhouse gases.

Pyrolysis of automobile shredder residue: an analysis of the products of a commercial screw kiln process

The products from the pyrolysis of automobile shredder residue, the waste produced in the recycling of old automobiles, have been studied. The pyrolysis process employed in the study was a commercial screw kiln unit. The chemical composition of the gas, liquid and solid fractions have been analyzed using a variety of techniques. The results of these analyses suggest that, while pyrolysis may represent a viable process for separating the organic materials from the inorganics, a full commercialization of the process must await a more detailed evaluation of the marketability of the products and their acceptance as feeds for full resource recovery.

Options for cement production in Papua New Guinea: A study in choice of technology

This paper examines the technical options for local production of cement to satisfy Papua New Guinea's needs. Both rotary and vertical kiln methods and different plant sizes are compared on economic grounds and also assessed against national objectives. Because of Papua New Guinea's small and scattered demand for cement and high internal transport costs, the smaller vertical kiln units are more economic while small-scale manufacture is also more in line with national objectives.

Drying and firstheat up of a kiln unit with cyclone heat exchangers with a lining of refractory concretes

An accelerated drying and first heat up cycle was developed for a kiln unit for dry production of clinker with a capacity of 3000 tons/day with cyclone heat exchangers with a lining of refractory concretes of high-alumina cement with a chamotte aggregate. The drying of the lining and the heating of the unit were done in 4 days. The results of the work indicate the desirability of use of refractory concretes for lining the cyclone heat exchangers of kiln units for dry production of clinker.