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Auto-ignition behavior of lubricating oil is studied experimentally using a cone calorimeter. Based on its Material Safety Data Sheet (MSDS), the adopted lubricating oil has a flash point temperature of 228°C, The measurement of auto-ignition behavior was carried at atmospheric pressure in range of temperature between 350°C to 550°C. In this work, the optical density of smoke resulting from the combustion process was measured at auto-ignition temperature. The result of this study shows that the auto-ignition behavior of lubricating oil is strongly depend on conditions of gas mixture, i.e. oil vapor, nitrogen, and oxygen mixtures. The lubricating oil started to ignite at irradiance temperature of cone heater at 500°C with a measured heat flux value of 16,7 kW/m2. At lower temperatures ignition of the mixture occured by piloted igniton sources. No ignition was observed at temperature less than 350°C. At higher irradiance temperature and heat flux (550°C and 21,1 kW/m2), auto-ignition occured at shorter time to ignition and producing higher value of smokes optical density of 1 - 1.4 m-1.

ADSORBENT SELECTION FOR CO ADSORPTION USING LANGMUIR ISOTHERMIC ADSORPTION MODEL. The objective of this research is to choose the adsorbent that can be applied to decrease toxicity level and to purify fire smoke. In case of fire, toxicity level is high due to carbon monoxide. Adsorbent is chosen based on its ability to adsorb carbon monoxide using volumetric method in constant temperature. Materials to be tested are natural zeolite, active carbon, TiO2, CuO, MgO. Due to existence of organic and mineral polluters, natural zeolite needs to be activated prior to adsorption test using fluoride acid (HF), chloride acid (HCl), ammonium chloride (NH4Cl) and followed by calcination process. Result shows that activation of natural zeolite can increase Si/Al ratio and surface area. According to Langmuir adsorption model obtained, adsorption capacity of active carbon and natural zeolite are the highest. At 1 atmospheric pressure, adsorption capacity are 0.0682 mmol/g for active carbon, 0.0464 for activated natural zeolite with particle size of 400 nm, and 0.0265 mmol/g for activated natural zeolite with particle size of (37-50) μm. Penelitian ini bertujuan untuk memilih adsorben yang dapat diaplikasikan untuk menurunkan tingkat racun dan menjernihkan asap kebakaran. Pada kasus kebakaran tingkat racun asap disebabkan tingginya kandungan karbon monoksida. Proses pemilihan adsorben dilihat pada kemampuan adsorben mengadsorpsi karbon monoksida, yang dilakukan dengan metode volumetrik pada temperatur konstan. Material yang diuji adalah zeolit alam, karbon aktif, TiO2, CuO, MgO. Zeolit alam banyak terdapat pengotor baik organik maupun mineral, oleh karena itu sebelum dilakukan uji adsorpsi, zeolit alam terlebih dahulu diaktifasi menggunakan larutan asam florida (HF), asam khlorida (HCl) dan larutan amonium khlorida (NH4Cl), dilanjutkan dengan proses kalsinasi. Hasil penelitian menunjukkan bahwa aktifasi zeolit alam dapat meningkatkan rasio Si/Al dan luas permukaan. Semua adsorben yang diuji mempunyai kemampuan mengadsorpsi karbon monoksida. Berdasarkan model adsorpsi Langmuir yang diperoleh, karbon aktif dan zeolit alam mempunyai kapasitas adsorpsi yang paling besar. Dengan menggunakan kondisi tekanan 1 atmosfir, kapasitas adsorpsi adalah 0,0682 mmol/g untuk karbon aktif, 0,0464 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel 400 nm dan 0,0265 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel (37-50) μm.

Low-temperature oxidation of two Indonesian low rank coals was characterized by Thermogravimetric analysis (TGA). The effect of particle size on the spontaneous combustion of coal was examined. Coals were classified to-599+299, -299+249, -249-150, -150+76 and-76 μm size groups and through non-isothermal method scanned from 24 to 600°C at heating rate 5°C/min with air flow rate 50 mL/min. DTA thermogram shows that the transition temperatures decrease by decreasing the particle size. Furthermore, the weight loss increases by decreasing particle size. It is indicated that the propensity of coal to spontaneous combustion increase with decreasing particle size. The moisture loss activation energy and oxidation activation energy were calculated by an integral method using the Coats-Redfern formula. The results show that the propensity for spontaneous combustion of two coal samples (judged by the activation energy) increases by decreasing particle size.

Smoldering is a slow, flameless and the most persistent type of combustion. Wildland fire or ground fire is an example of smoldering combustion which has become one of the most important issue in Indonesia and no effective solution has been found to solve this phenomenon yet. The organic materials contained in peatland can potentially become a flammable fuel with the presence of a trigger for wildland fire. In this experimental work tobacco material was used to study smoldering phenomenon. The relation between material density with temperature distribution and mass loss rate are conducted in the experiment. The transmissivity of the smoke produced by the smoldering combustion will also be analyzed. Experiments are carried out for the material density ranging from 0.12 - 0.2?g/cm. The result showed that smoldering combustion are affected by density, due to the allowance of airflow and heat propagation. The result showed that material bed with the lowest density of 0.12?g/cm has the slowest smoldering velocity and mass loss rate while the material bed with the highest density of 0.2?g/cm has the fastest smoldering velocity and mass loss rate. The smoke took a longer period time to reach the bed surface at higher bed density.

Electrical cable is a whole of the material including metal (cooper) conductor and its insulation, when an electrical cable is flowed by electric current, based on its own capacity, the temperature of cable conductor increases gradually. If the current flows above the cable carrying capacity, then an extreme temperature rises are expected. When temperature increase, the electric current flow inside cable conductor will decrease gradually related to the resistance and could occur repeatedly in a period. Since electrical faults on electrical cable system are often suspected as the cause of fires, thus this research aims to investigate measures of preventing the fire to start by means of controlling oxygen concentration in a cable compartment. The experimental work was conducted in laboratory by using electrical power cable of 1.5 mm2 size. Two transparent chambers were applied for studying the effect of vertical and horizontal orientations on the cable temperature rise, under various oxygen concentration of...

Fire accident remains a problem in modern society. This leads great efforts in finding ways to prevent, detect and control it. Conventional fire detection systems are mostly point detectors, which have limitation for early smoke detection, especially in a high-ceiling atrium. A video-based smoke detection system is an interesting alternative approach. It has better area coverage and detecting smoke faster. In this work, a video-based smoke detection system was developed with two main processes, i.e. moving objects segmentation with Gaussian Mixture Models (GMM) and smoke classifications with Mathematical Model of Meaning (MMM). In the MMM model, the interpretation of dangerous smoke is based on the context provided. Then the classification results are compared with conventional smoke detector. The results show that MMM can recognize the dangerous smoke faster than conventional smoke detectors.

In oxy-fuel combustion technology, the coal is burned in a mixture of pure oxygen and recycled flue gas with high content of CO2 gas. Burning the coal in oxy-fuel combustion with O2 and CO2 environment will affect the combustion performance compare with air (O2/N2) environment. Based on previous researches indicated that oxygen concentration is required to be increased, so that the combustion behaviour similar as in air environment. This paper describes the characteristics of coal ignition and combustion in oxy-fuel combustion applying the non- isothermal thermogravimetric analysis. Experimental results find out the activation energy of three different coal ranks in O2/N2 and O2/CO2 environment. Temperature of coal sample and inert reference material can simultaneously measured in TG-DTA. Based on activation energy and TG-DTA data, predicted coal particle ignition temperature can be calculated and then validated. The result is successfully applied both in air and O2/CO2 environment. In comparison to the conventional combustion, thermogravimetric curves of coal combustion in O2/CO2 tend towards higher temperature zone. The species in flue gas during burning test in TGA were determined and analyzed using the Fourier-transform infrared (FTIR) spectrometer. Compared with pulverized coal combustion in O2/N2 environment, much more CO is produced in O2/CO2 coal combustion process. Refer to two film model, the delay in oxy-fuel combustion may be caused by the incoming O2 unbalance with much CO gas, and this can be solved with increasing O2 concentration in O2/CO2 environment.

This paper examines wildland and urban fires situations in Indonesia. On one hand, during the dry season when wetland dry out, large scale wildland/forest fires may occur on dry land and also on wetland such as peatland or peat-forest. Wildland fires, especially when involving peat land fires can be viewed as a regional and global disaster. Smouldering combustion of peatland fires produces thick haze that directly impact the life of the local peoples and can spread to other region and neighbouring countries. On the other hand, as consequences of economic development, rapid urbanization occurs. It is expected that larger portions of the populations will move to urban areas result in higher densities of people and complex highrise buildings and lines of utility infrastructures. These new build environments are prone with urban fires problems. Risk reduction efforts in wildland and urban areas becomes more significant than ever. Better understanding of fire phenomena in urban and wildland areas, and the needs of fire hazards response management, leads the efforts in integrating wildland and urban fire risks in national and local development strategies in Indonesia. © Springer 2015.

Developments of urban areas must consider mass transportation of people generated by economic activities and their impact on public safety. Fire remains a great challenge for the city’s planner as its occurrence in crowded and busy areas could result in a fire disaster. A fire disaster in a mass public transportation system could cause serious impact due to the number of people involved. During design stage of new mass rapid transit lines, the walking characteristics of the local passengers should be greatly considered. This paper critically analysed passenger movement at the three busiest commuter line stations in Jakarta. The survey was carried out during the peak hours both in the morning and in the evening. It is observed that the walking speed of the passenger was affected by density at various locations measured on the platform and concourse levels as well as at the ticket gates. The corresponding value of the specific flow was also derived to frame the average value that could be considered during the design stage of a new line. In general, the study shows that both the average walking speed and the specific flow of the local passengers are slightly lower than the average value given in the international standards such as NFPA 130 (USA) and MLIT (Technical Standard Requirement for Japan Railway).

One way to avoid the loss of life in building fires is by performing effective evacuation. As a consequence of economic developments, cities of the world continuously build high-rise buildings, including super high-rise ones having more than 40 storeys. When a building has to perform full evacuation, the long travel distance in a super high-rise building can cause delay to reach exit discharge locations on the ground floor. Although a number of studies have been carried out to identify the characteristics of evacuee during emergency, it is suggested that the evacuation behaviour may be affected by cultural background of the persons (Ozkaya A 2001) [1]. This paper is intended to gather building evacuation time, vertical movement speed data and to study the behaviour of occupants during evacuation in medium- and high-rise buildings. The study was carried out mostly in Jakarta, Indonesia. The evacuation time and overall movement speed were observed by gathering the data during a typical evacuation drill in the medium- and high-rise buildings. The result suggested that vertical movement speed descending from the fourth floor is around 0.70–0.81 m/s. As the evacuee is descending from the higher floors, the lower movement speed was identified, e.g. around 0.62–0.75 m/s for those descending from the ninth floor and around 0.50–0.73 m/s for those descending from 19th floor. The trends are in good agreement with other works suggested in the literature. From the surveys, regardless of the occupancy, i.e. whether the building is an office, a college or shopping avenue, interesting behaviours of the evacuee during evacuation process were identified. While travelling downwards, evacuees tend to evacuate in groups, to walk side by side with other members of the groups, and some of them hold the stairs’ railing. These caused queuing and congestion, especially if the exit stairs’ width only fit two people walking side by side.

Oxyfuel combustion is one of promising clean coal technologies for capturing CO2. Different environment in oxyfuel combustion between air condition and O2/CO2 condition is required to be studied. Thermo-gravimetric analyzer (TGA) and Fourier-transform infrared (FTIR) spectrometer was used to study the behavior of pulverized coal in different O2/CO2 environments. The burning process of pulverized coal in O2/CO2 environment was relative similar until burning the volatile matter and then combustion was delayed in burning the char compared with that in O2/N2 environment at the same oxygen concentration. In case of the oxygen concentration increase, the burning rate of coal increases and burnout time is shortened. The species in flue gas including H2O, CO2, CO, CH4, SO2 and NO during burning test in TGA were determined and analyzed using the Fourier-transform infrared (FTIR) spectrometer. Compared with pulverized coal combustion in O2/N2 condition, much more CO is produced in O2/CO2 coal combustion process.

In this work a flexible design of multi-nozzle arrangement of water mist fire suppression system was studied. The source of fire was a 65 mm diameter cooking oil fire. An investigation on the impact of nozzle arrangement on thetemperature profile of fires was conducted. The occurance of oil splash due to the application of water mist was also studied. The water mist systems developed in the present work can effectively extinguish cooking oil fires andprevented them from re-ignition. The spray angle, discharge pressure, and water flow rate were important factors to determine the effectiveness of water mist in extinguishing cooking oil fires.

Solving peat fires problem continues to be a constant struggle in Indonesia as more hotspots are identified during the dry seasons. A number of research has been carried out to understand the most sufficient way to suppress peat fires using a range of different methods. This research was focused on the suppression of peat fire by using foaming-based suppression agent in the laboratory scale experiments. Experiments were carried out to explore the effect of foam suppression system on tropical peat fires. A solution of Class A Foam with a concentration of 3% was used to suppress Kalimantan peat fire with a density of ±0.3g/cm3 . Sample used in the experiments was taken from Tumbang Nusa Village, Pulang Pisau District, Central Kalimantan Province, with a coordinate of S: -3⁰47’34”, E: 113⁰55’15”. This experiment will explore how many foam layers of certain heights are needed in order to extinguish peat fire. Peat sample was put in a 10x10x10 cm3 reactor, where a coil heater was turned on at 80 - 100W for 30 minutes to initiate a smouldering front. A set of type K thermocouples and infrared thermographs were used to explore the suppression mechanism that occurs. As the smouldering front moved away from the igniter to the other end of the reactor, foam with different thickness was poured on top of the peat to explore the effect of varying thickness on the suppression of peat fire. From the series of experiments, it was observed that there was a correlation between the thickness of the foam layer and the suppression of peat fires. The thickness of 10cm was found to be the most effective in terms of time at extinguishing peat fire. An average amount of 3.8L of foam per kilogram of Kalimantan peat was needed to extinguish peat fire. It was also found that the average amount of water needed to suppress peat fire using foam method was 3.4L/kg.

Forest fire is one of the greatest environmental problems faced by Indonesia. Forest fires have destroyed million hectares of forest and land which cause economic loss, social problems including smoke related diseases and environmental disaster with long time consequences. The exothermic reactions of forest fuels that lead to fire can be initiated by a piloted flame and low-temperature oxidation mechanism. This paper presents the results of low temperature oxidation studies using forests fuel samples i.e. palm shell fibre, peat, woods and low-rank coal. The measured values of the critical oven temperatures and the kinetic oxidation parameters are used to analyze the intrinsic properties of the samples to self-ignite. Thermal runaway reactions leading to ignition are indicated for all forest fuels tested. This reaction is affected by various factors including oven temperature, moisture content, chemical and physical properties as well as basket sizes. Attempt to extrapolate the results of these laboratoryscaled experiments for real fires still require further tests and assessments.

In order to execute the global issue mandated for an environmentally friendly vehicle, research on the hybrid electric vehicle (HEV) has been developed in the Mechanical Engineering Department of Universitas Indonesia (MED-UI). The ultimate goal of this research is simply to develop a low-cost HEV which uses energy most ef- ficiently. A small-sized HEV seating one to two passengers has been the main focus towards completing this ulti - mate goal. Five prototypes in ten years have been developed, and Prototype III is one of the most inventive. The major features of this prototype are the power take-off system, frame design and the control system.

A spontaneous increase in coal temperature with a possible transition into fires represents a direct hazard to coal storage and transportation. This paper evaluates the self-heating characteristics of a sub-bituminous coal under adiabatic oxidation conditions. This paper assesses the effect of relative humidity of the gas supply on the self-heating rates of coal. It is shown that an increase in the gas supply relative humidity has a marked affect on the self-heating rates of the coal. In this work the sub-bituminous coal sample undergo oxidation most rapidly when the relative humidity of the gas supply is about 70%. The effect of relative humidity decreases as oxygen concentration in the gas supply increases. A practical consequence of this finding is that improved fire safety measures should be considered during sub- bituminous coal related operations in hot and humid regions.

This study aims to investigate the effectiveness of water mist on suppressing a shielded fire. Full-scale experiments are carried out in a partition room of (lxwxh) 2x2x2.5 m size. Five water mist nozzle which consist of two type nozzle was used, high flow (fogjet) nozzle installed at top center of the room and fine spray nozzle installed at each side of room at high 1.5 m from ground. The pressure of water mist system was maintained at 20 bar which correspond to 2.6 lpm of water flow rate. Wood crib of 6.5 x 6.5 x 6 cm size was used as the fuel source. The obstruction used as a fuel shield has table like form with 40 x 40 cm cover area and 0.5 m height. The location of fuel source and fuel shield was varied (1) fuel source and shield at centre of room, (2) fuel source at one side of shield and the shield at centre of room, (3) fuel source and shield at corner of room, and (4)) fuel source at one side of shield and the shield at corner of room. Numerical simulation using FDS 6.5.3 was also performed to validate the use of FDS and get better understanding of the phenomena. The results showed that water mist was able to extinguish the fire around 20 s, 16 s, 30 s, and 24 s for scenario 1, 2, 3 and 4 respectively. It is also observe that the mist distribution around the shield and cover area of the shield play a role on the capacity and time needed of water mist to extinguish the fire.

The rapid development of science and technology have contributed in the applied building design. One of them is the improvement of the construction design of the building envelope. Current high-rise building design impacts in wider building envelop surface area and greater heat load received from the sun irradiation. One of the common used design is the doubleskin façade type building envelope. The insulation characteristic given by the envelope interlayer gap can reduce the heat load received. However, in fire cases, the gap becomes hot gasses path, supporting wider flame propagation. Its position in the outside leads to harder fire suppression effort. During this time, the active fire protection system design has just considering fire scenarios inside the building. This research is conducted to see water droplets impact as extinguisher aspect on interlayer gap hot gasses propagation. The experiment used wooden layer with 540 mm x 80 mm x 6 mm dimention as the envelope layer. The interlayer gap varies among others 30 mm, 50 mm, and 70 mm to see flame output characteristic through and time needed for 4 nozzles to extinguish the flame. The suppression system applied is expected to be a solution in the case of double-skin façade building envelope fire event.

Indonesia is a country with the largest peatland in Southeast Asia. These vast peatland is spread throughout the country. In the last 2 decades, Indonesia encounter land fires and now becomes an annual land fire event. Later, observed that the land fire occurred because dry season in Indonesia causing the peat becomes dried enough to have hydrophobic characteristics and easily burned. This fire phenomena on peatland is determined by some factor such as, physical properties, organic content, oxygen concentration, etc. Peat has hydrophilic and hydrophobic properties as physical properties when treated differently. Initially raw peat has hydrophilic properties. However, in certain low level of moisture content, peat becomes hydrophobic. To examine this phenomenon, mechanical understanding based experiment was done. For hydrophilicity, the experiment will be using Shimadzu MOC63u Moisture Balance Analyzer. The peat sample which are used are Indonesian natural peat. The wet peat was dried by using moisture balance equipment with various time (0.5 till 6 hours with interval 0.5h) at 100°C. and loading peat into a tube with 2.15 cm in inner diameter and 5.5 cm long where both end are covered by wire mesh. Afterwards, the tube was being dipped into water in a certain depth. As for hydrophobicity, the experiment was done with the same method as hydrophilicity by using some of the dried peat. From the experiment, the mass loss, adsorption time, volume shrinkage and adsorption capacity and as well as hydrophobicity of peat will be shown in the result.

This paper presents studies on the influence of the nozzle tilt angle on the on the thermal radiation generated by diffusion jet flame. Analysis was limited to the nozzle tilt angle, distance and height of the heat flux measurement, and nozzle diameter. The studies were conducted for three different nozzle tilt angles of 0o, 45o and 90o, three different distances 10 cm, 15 cm and 20 cm, six different heights 10 cm, 20 cm, 30 cm, 40 cm, 50 cm and 60 cm, and two different nozzle diameters 17 mm and 11 mm. The thermal radiation intensity increased with the distance and height of measurements. The variation of horizontal and vertical jet flame was found to follow a linear equation. The studies also included investigation of flame shapes influence on the thermal radiation. The obtained results are presented in a graphical and tabular form. Based on the analysis of results the conclusion are established, important not only for the theoretical considerations but also in practice, especially in the context of immediate ignition on Liquefied Petroleum Gas as fuel for household leakage.

During the past 40 years, there have been 14 major accidents of oil spill in Indonesia, mostly as results of ship collisions. There are several methods in handling oil spill accident, in which the most effective methods are using mechanical oil skimmer with disc plate. The effectiveness of the oil skimmer on handling oil spills is influenced by various factors, such as the depth of the disk submerged or the disk surface area dipped into the oil spill, the area of the wiper sweep, the thickness of the oil on the disk surface, and the rotation speed of the disk. This paper presents the results of laboratory scale experiment of mechanical oil skimmer. The oil samples used are diesel engine oil with 15W-40 SAE and the water sample used is sea water. The experiment was conducted with variation of 27 mm and 55 mm of disc submersion depth or equal to dipped surface area of 31.35 cm2 and 88,832 cm2. The duration of the test for 3 data is 5 minutes. Based on theoretical calculations, the increase of rotation speed of the disk, the result of spill transport will also be higher. This is proved by the experimental results. The lifting process of oil spill is more effective with low rotation speed, because the result of oil spill transported will be more dominated by oil than water. In this test, the higher the rotation speed of the disk, the higher the water produced.

Heat transfer always occurs in human life and can be perceived its benefits and losses. The heat transfer is divided into three according to transfers media, namely conduction, convection, and radiation. One example of cases where there are three processes of heat transfer is when there is a fire in a room. During a fire, the heat from the fire will travel into the surrounding environment and affect the objects around it with radiation, conduction, and convection. Heat that travels through radiation certainly does not require a medium of delivery because the heat is traveled in the form of electromagnetic waves and can travel to a very long distance. Distance, view factor, and placement of an object will affect the amount of radiation to be received from the heat of fire. Therefore, to examine the effect of distance, the viewing factor and the placement of objects against radiation, writer designs a multi-axis heat flux sensor. Instrument with multi-axis heat flux sensors or by the name of a Multi-Axis Radiometer will be designed which will then be tested to determine the results of the design. Instrument called Multi-Axis because the workbench of the instrument can be rotated 90°. Testing of the apparatus will include the heating temperature, the distance of the sensor to the heater, the sensor offset to the heater, the viewing angle of the sensor to the heater, and the orientation of the workbench. The results of testing distance and offset are validated by the theoretical calculations.

The rate of energy needs in Indonesia has increased and the availability of derived fuel energy from fossil has waned. It became worse because of the increase of the population growth, followed by the accretion of life needs that impact on the increase of fuel needs. As much as 55 % fuel oil is used for household industry and transportation. This condition motivates the government to develop alternative energies which are cheaper, renewable and environmentally friendly. One of them is the utilization of sago waste to produce bioethanol as alternative fuel source to fulfill the energy availability in our country especially in the provinces. The Sago potential in Indonesia is ± 1 250 000 ha, where ± 1 200 000 ha of which is in Papua. Thus, Papua has the largest sago potential in the world. This study was conducted to produce clean combustion processes that are healthy, fuel saving and environmentally friendly. The research method consisted of three steps; they were the production of bioethanol from sago dregs using fermentation, the test of fuel characteristics of lower heating value using a bomb calorimeter and the measurement of combustion efficiency with water boiling test as well as heat release rate using a cone calorimeter. The fuel used was bioethanol from sago waste that contained 60 % ethanol.

Fire onboard ro-ro ferry usually claims a great number of casualties. In Indonesia 41% of major marine accidents were fire accidents. Victims of ferry fire accident are usually due to smoke, heat, and low visibility. The research is aimed to simulatethe flow of heat and smoke during a fire from car decks of the ferry to passenger decks and how the fire safety systemsprovide sufficient time for the passengers to escape from the affected areas. Fire Dynamic Simulator V5 (FDS V05) software was used in three different fire scenarios namely without sprinklers; with sprinklers but without smoke exhaust and fresh air supply fans; and with sprinklers, smoke exhaust and fresh air supply fans. It is proven that water sprinklers could suppress the distribution of heat, and smoke exhaust and fresh air supply fans have contribution in maintaining the visibility.

The oxidation of different types of coal under self-heating conditions is considered using the crossing point method performed in a cubical wire-mesh basket. This study investigates the effect of particle size and the physical structure of coals (including pore size and surface area) on the self-heating character of high and low rank Indonesian coals and their blends. The results confirm that both particle size and surface area give considerably different effects on critical ambient temperature, the activation energy and the product of exothermicity and the pre-exponential factor of low and high rank coals. It was found that the self-heating characteristics of high rank coals were strongly dependent upon the particle size of the coals. For low rank coals, the dependence was weaker. A coal bed with mixed sizes is thus more vulnerable than one with segregated sizes. This means that one must carefully consider the particle size distribution to judge the spontaneous ignition behaviour of coal. It is suggested that the potential for spontaneous combustion of blended coal is greater following the increased percentage of more reactive coal.

Greater use of international coal and low-sulfur/low-rank coals brings new challenges in monitoring the spontaneous combustion behavior of these coals during transport in stockpiles, and in coal milling systems Extensive experimental work has been carried out to measure the kinetic parameters of low-temperature oxidation of a number of coals for varying particle fractions. A substantial set of experimentally measured values of activation energy, E a , and the product of the exothermicity and the pre-exponential factor, QA , have indicated a strong relationship, which is shared by coals of different ranks and of different particle size. This correlation for E a and QA leads to a new approach for estimating the thermal runaway behavior of coal piles based on small-scale experiments. By use of Frank-Kamenetskii theory, the correlation curve fit of E a versus QA can be used to estimate hazardous conditions at varying scales by small-scale oven heating tests measuring the heat release rate at low temperatures. The results suggest that the increasing size of the pile alters the particle size effect. For large coal piles, large particle size can increase the potential for spontaneous combustion. This new approach provides a more cost-effective assessment of the susceptibility of various types of coal to self-ignition.

Indonesian coal, although generally low in sulfur and ash content, is a lower rank coal with a relatively high moisture content (5–18%). Consequently, it has a greater propensity to self-heating behavior, and the aim of this paper is to assess the hazard for three typical coals that are used both domestically and for export. Experimental tests are reported using a new technique (the crossing point method) to determine the activation energy and reactivity of the low-temperature slow oxidation reaction. This uses the transient temperature profiles to deduce the activation energy and reactivity of the sample. The method relies on finding the center temperature at the point when a flat profile is observed (Called the crossing temperature) and has been used successfully to ascertain the kinetic parameters of three Indonesian coal samples. It is found that the method is valid as long as the coal experiment is not greatly supercritical when it is then difficult to determine an appropriate crossing temperature. The method has the distinct advantage over the traditional Frank-Kamanetskii approach, in that only one oven experiment is needed for any one point on the kinetic plot, and that the results are not heavily dependent on the fan setting of the oven, or on sample size. A comparable experiment using the Frank-Kamanetskii approach of finding the critical temperature for different sample sizes showed good agreement for estimating activation energy.

Roll on roll off passenger ferries play very important role in connecting Indonesia’s more than 17,000 islands. Since these ferries are categorized as ‘Non-convention’ vessels they are not mandatory to comply with international regulations, therefore they are very vulnerable to accidents including fire accident. The study was carried out to establish onboard fire safety assessment standards for Roll on roll off ferries operating on Indonesian waters to be used as guidance for authorities and operators to assess and to ensure the safety of the ferries. The assessment standards are focused on three accident sources include: the vessel; people on board; and the cargo. The standards are derived from fire hazards and their potential risk levels, which are categoriesed as intolerable; tolerable; and negligible. Refer to the risk levels obtained realistic and appropriate actions could then be implemented to prevent the ferries from fire accidents.

In this study, modeling of the crossing point temperature (CPT) phenomenon in the low-temperature oxidation of coal was carried out using COMSOL Multiphysics®. Low-temperature oxidation can lead to spontaneous combustion of coal stockpiles. The CPT phenomenon was modeled with the kinetics data obtained from a prior laboratory experimental study. The coupling of the heat-transfer phenomenon through conduction and convection determined the thermal evolution model. In this case, coal received the initial heat of the oven temperature increases. As the coal temperature rose, the heat generated from oxidation was released into the environment via conduction and convection. Meanwhile, oxidation products and oxygen were transferred by convection and diffusion. The effects of moisture and the humidity were not considered. The outcomes of modeling were validated through comparison with the results of experimental tests, and the modeling result agreed well with the experiment tests, with temperature deviations of about 0.9%. The effects of airflow rate, oxygen concentration, porosity, and the initial temperature on low-temperature coal oxidation were also examined.

Gasification process at updraft gasifier produces the amount of more tar than the other gasifier type. To reduce tar at updraft gasifier, it is carried out recirculation of pirolysis gas into combustion zone. Ejector is an equipment used to entrain the secondary fluid flow by moving momentum and energy from high velocity of primary flow (jet). Research carries out the simulation of isothermal 3D using Computational Fluid Dynamics (CFD) to obtain the maximum of recirculation flow at updraft gasifier using ejector. The result of simulation shows that change of nozzle diameter gives great influence at change of total flow for resirculation compared with the change of diameter and length of mixing area and nozzle exit position (NXP). The maximum of resirculation flow 81 lpm at nozzle diameter 0.75 cm.

Popularity of water mist is increasing for a variety of applications within the broad areas of fire suppression and surface cooling. The present study has been focused on characterizing the water-mist spray for a nozzle and interaction of two nozzles in a 5 cm distance to each other. Full-cone nozzle were operated at medium operative pressure of 6, 10 and 15 bars with expected volume mean diameter of 110 μm. The aim of these works is to investigate a quantitative description of density profile for a nozzle and interaction of two nozzle employing optical techniques by image processing technique. The main characteristics of the mist spray was defined by using the gray level in certain areas. The measurement indicates that higher throw length can be achieved at higher pressure. In the case of two nozzle interaction, the uniform density profile was identified at shorter distance from the nozzle tip at higher water pressure, and the technique for capturing density profile two nozzle interaction was validated with mass flux measurement. A simple measurement technique has been developed in this on going work.

Gasification process at updraft gasifier produces greater amount of tar than other type of gasifier. To reduce tar at updraft gasifier, the pirolysis gas will be re-circulated to combustion zone and to exhaust gas from reduction zone. Recirculation of pirolysis gas to combustion zone can be carried out by using ejector. Ejector is an equipment used to inject the secondary fluid flow by the movement of momentum and energy from high speed primary flow (jet). The research conducted with isothermal 3D simulation using CFD and experimental investigation of recirculation flow using ejector at updraft gasifier. Ejector velocity for simulation and experimentation is constant at 0.6 m/s. Ejector’s nozzle exit position (NXP) direction will be varied. The goal of this research is to obtain information of optimal nozzle exit position for producing maximum velocity of gas recirculation. The result of simulation and experiment shows that the change of nozzle exit position direction to – x axis from zero point, it will give maximum velocity of gas recirculation flow with the optimum position of nozzle exit position at the range of -3 to -4 cm from zero point.

Self-ignition properties of peat, palm shell fibre and woods. Forest fire is one of the greatest environmental problems faced by Indonesia. Forest fires have destroyed million hectares of forest and land which cause economic loss, social problems including smoke related diseases and environmental disaster with long time consequences. The exothermic reactions of forest fuels that lead to fire can be initiated by a piloted flame and low-temperature oxidation mechanism. This paper presents the results of low temperature oxidation studies using forests fuel samples i.e. palm shell fibre, peat, woods and low-rank coal. The measured values of the critical oven temperatures and the kinetic oxidation parameters are used to analyze the intrinsic properties of the samples to self-ignite. Thermal runaway reactions leading to ignition are indicated for all forest fuels tested. This reaction is affected by various factors including oven temperature, moisture content, chemical and physical properties as well as basket sizes. Attempt to extrapolate the results of these laboratoryscaled experiments for real fires still require further tests and assessments.

A series of laboratory tests for electrical fires have been carried out by researchers, and some of the results have confirmed and been adopted as standard. However, the studies focus on electrical fires in PVC insulation material and the melting temperature and toxicity of PVC insulation. By focusing on heat conductors, the growth and spread of a fire can be eliminated by reducing the oxygen concentration, especially inside the compartment. Electrical fires are the most common cause of compartment and building fires both internationally and nationally, according to statistics (Liu & Benichou, 2008). Whatever the triggers are inside the electrical compartment on the connection, termination, or cable, this research looks into electrical fires caused by 1.0–1.5 mmsq electrical cables. Electrical fires in cables are normally started by increasing temperatures inside the cable conductor. By controlling and adjusting the oxygen concentration inside the electrical compartment under atmospheric concentration, one can hamper a fire’s start, trigger, propagation, and growth. This study investigates the effectiveness of oxygen concentration on preventing the growth of fires triggered by electrical cabling. A series of studies were created in laboratory scale in a horizontal compartment with oxygen levels of 19%, 17%, and 15%. This paper presents the results of this experiment by studying the effects of reducing oxygen concentration on the fire growth in cable network in a horizontal orientation. The results show that controlling the oxygen concentration at levels lower than atmospheric concentrations can effectively reduce the propensity for cable ignition and lower the fire propagation rate.