Accelerating Rate Calorimeter The World’s Benchmark Adiabatic Calorimeter System “The Accelerating Rate Calorimeter is unique for its unparalleled adiabacity, its sensitivity and its sample universality. Coupled to this its ease of use and simple data analysis make it accessible and usable by all”” THERMAL HAZARD TECHNOLOGY 1 North H 1 North o H use us Bond A Bond v A enue enu Bletchley Bletch MK1 1SW MK Phone: Ph 01908 646 01908 646800 01908 646 Fax: Fax 01908 645 01908 645209 01908 645 Info@thermalhazardtechnology.c h om www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter An und n ers e tan a din d g of th g of e energy release from rea re c a tion ti b on e b r e e r li e ab li l ab y e v e alua al te ua d te b d y b si mul si a mul ti a n ti g n g chemical reactions n and n what a can ha ca pp n ha en on a a the potential for r larg a e scale by mimicking runaw a ay a reactions is the w the o w rs r t case t ca z se e z ro r --he heat at vital vi l tal y im i porta por n ta t n in i t n he he he loss con loss condit di ions tio ti n o . s. chemical industry. ry. W h e n t h e h e a t t The Accelerating Rate e generat ed by a a Calorimet e er is the most t chemical a process is process is well k e now n n and world's greater than the e most wi most w de d ly us u ed e d ad a ia d b ia a b t a ic c possibl possi e bl he e a he t a re re r moval re , moval calorimeter and will the tem e perature w r ill ll i provide full info d rmat rma ion on rise with perhaps the heat and pressure e catastrophic effect. ct. release showing the e M o s t c h e m i c a l potential a of a runa of a w runa ay y rea e c a tions procee r d with th occurring. This occurring. Thi will also heat release but the am e a ount of h f eat e release, enab en l ab e opti pt mu im m con um c um o c dit nditions ions to be to t b o e b e e m employe ploy d to ed to ed t o the rat a e of re e lease and t n he tem e perature o r f e o f allow inherently safe ope a ration. On n ly when onset a e r t a e ve r ry important para ry importa meters nt para . On . O ly in tests a te r sts a e r co e nd n ucte d d ucte d in a tr n ul a tr y a ul d y a ia d ba ia ti ba c sys ti t c sys em e m an ad an a iabati ba c ca ti lo c ca rime ri te me r can su te ch a r can su runa ch a wa way wa y it possibl possi e bl to scal e e to scal -up from the l up fr up f om the r a labor b la o b a ratory sca tor ra y tor l sca e e e www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter The system is contained in a metal sphere 2.5cm in be reduced to zero. diameter, typically of Titanium or Hastelloy C. The The calorimeter operates adiabatically allowing sample mass is usual y 2-8g but would depend the - calorimeter temperature to track sample upon the expected energy release and type of temperature. This wait period (typical y 10-15 sample container (known as a bomb) used. The bomb is attached to the lid section on the minutes) is followed by a seek or search period. calorimeter assembly by a pressure fitting and a Again during this period (typically 20 minutes) no pressure line leads to the pressure transducer. A heat is provided by the radiant heater, and any fine thermocouple is attached to the outer surface temperature drift, upwards or downwards, is of the bomb and the lid of the observed. If there is upward calorimeter then positioned on the temperature drift this is caused by base section. The calorimeter has a self-heating reaction. The heat- three separate thermal zones. The top (lid section) contains two heaters wait-seek procedure, the normal and a thermocouple, the side zone mode of operation of the of the base section contains four Accelerating Rate Calorimeter, will heaters and a thermocouple and the continue until an upward bottom zone at the base section temperature drift observes an contains two heaters and a exothermic reaction, greater than thermocouple. After set up and the selected sensitivity (normally connection, the calorimeter is sealed w ithi n an explosi on proof 0.01-0.02°C/min). The system containment vessel. After defining automatically switches to the experimental conditions on the PC, exothermic mode; the system will the test can commence. The test apply heat to the calorimeter jacket conditions are a start and end to keep its temperature the same temperature and choosing the size as the bomb/sample. of ‘heat steps', 'wait time' and detection sensitivity'. The system will firstly heat to the start The adiabatic control is the key temperature. To do this, a small heater in the feature of the Accelerating Rate Calorimeter. The calorimeter, the radiant heater, applies heat. This system continues in the exotherm mode until the heats the sample, bomb and it's thermocouple. The rate of self-heating is less than the chosen calorimeter is cooler and this temperature sensitivity, at this stage the heat-wait-seek difference is observed by the three calorimeter procedure resumes. When the end temperature is thermocouples. The system will then apply power reached (or an end pressure is reached) the test to the calorimeter heaters to minimise the automatically stops and cooling, by compressed air, temperature difference. This will continue as the temperature rises to the start temperature. When begins. The aim of the Accelerating Rate this start temperature is reached the system will go Calorimeter is to complete the test to get a full time, into a wait period, during this time no heat is temperature, and pressure profile of the exothermic provided by the radiant heater. This allows the reaction in a safe and controlled manner. temperature differences within the calorimeter to www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter The World’s Benchmark Adiabatic Calorimeter has been Re-Engineered Introducing…. the Low φ Accelerating Rate Calorimeter Continuity Proven design, same bomb types, same mode of operation Results will be the same as those obtained from older style instruments Enhancement Low Phi (φ =1.05)…Fume Extraction…Cryogenic operation (Testing from –35°C)… True Isothermal Age mode…Rapid track option…Heat and Gas generation plots, SADT and tnr calculations … Network-able… Industry standard hardware and software Expansion Vent Size Unit…Sample Stirring Unit…Sample Dosing Unit….Automated Gas Sampling Unit… Gas Scrubbing and Safe Release Unit (manual or automatic…Cryogenic unit…Battery Safety and Cycling Units – see separate brochures “to assist scientists and engineers involved with safety and hazard testing and analysis” www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter TThe he Re-Engin Engineered Engin A eered cc c e c lerating Rate lerating Ca Rate lorimeter Ca First available in 1978, but little changed since, full re-engineering of the Accelerating Rate Calorimeter had been overdue. However with many original systems in use and a worldwide acceptance of the data produced, the first need was for Continuity of the data, but with re-engineering there is the possi-bility of enhancement and expansion of this proven technology. The re-engineered instrument offered by Thermal Hazard Technology allows for all of these aspects. The original well thought out features have been retained but modern microprocessor technology and computer control have been adopted. C Cont ontinuit nuity The Thermal Hazard Technology Accelerating Rate Calorimeter operates in the proven heat-wait-seek method and has isothermal capabilities. The calorimeter assembly is of the same proven design and the sample containers commonly available may be used. The performance of the system and its main char-acteristics remain unaltered and sample data from this instrument mirrors that of the original, thus there is continuity of data. Enhancement nhancement The hardware and software components are built to international standards, using recognised plat-forms. The design is such to allow expansion. In addition, the calorimeter containment vessel is designed to allow for improved access, gas extraction and housing of additional equipment. 60ml containers mean f values to 1.05 are obtained. Software design has a user friendly GUI. E Exp xpa xp nsio ansion ansio Thermal Hazard Technology Accelerating Rate Calorimeter has therefore been designed to fulfil the requirements of an adiabatic calorimeter system but with the ability for ongoing enhancement and development. Options are available; a Vent Sizing Unit is available to allow low f testing, determination of reaction types and for blow-down tests for the determination of relief vent area. There is sample-stirring option, a sample dosing option, a gas collection option and a cryogenic option; there is a gas scrubber system to al ow safe removal and disposal of potentially toxic gases. www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Unparalleled nparalleled Adiaba nparalleled ticity Adiaba Exceptional Sensitiv Exceptional Sensiti ity it Proven adiabatic environment around whole sam-Detection of exotherm from 0.003°C/min self-ple, with high precision tracking of exothermic re-heating, which may be 100W/tonne. actions. U Universali niversalit niversali y of Sampl y of Sample y of Sampl Easy to Easy Use to Sample range, very low energy to very high-International y recognised technique - set-up energy reactions Sample range, liquids solids sala-time before and after a test of 10-20 minutes. ries residues mixtures gases Sample hazard range, processing, storage, transportation. Simple Data Analysis imple Data Analysis The data from a standard test is column and row data of time, temperature and pressure. From this raw experimental data the self-heat rate, pressure rate, time to maximum rate and all other data types are generated. The data analysis is semi-automated though may be fully analysed manual y if preferred Accelerating Rate Calorimeter data has always been considered straight forward to use and apply and this is also the case the Thermal Hazard Technology software. In addition the data analysis al ows for input of reaction vessel information to enable maximum safe temperatures or sizes to be determined. There is provision for other types of data analysis, e.g. SADT determination and an automatic report generator is provided. This and the graphical outputs may be user modified to customise or the change. The data analysis allows for production of quality colour output in slide or transparency format. www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Di-Tertiary Butyl Peroxide is the chemical usually chosen to illustrate the data from an adiabatic calorimeter. Results obtained from the Thermal Hazard Technology Accelerating Rate Calorimeter are shown below. The data shown here is for illustrative purposes, it shows what may be obtained from a single Accelerating Rate Calorimetry test. The DTBP test is useful as it clearly shows the performance of the system the accuracy of the data and the ability of the system to operate adiabatical y In this test 6g of 20% DTBP (98%) by weight in toluene (99 8%) is used. The bomb is a titanium bomb close to 6g in weight. Starting temperature is 90°C; end temperature 220°C the wait time 15 minutes the heat step 3°C and the onset sensitivity 0.01°C/min. Below and more importantly at temperatures above the exothermic reaction it is possible to see how well calibrated the system is and it can be noted that there is little if any drift. This indicates that there is little if any heat loss from the system - many other calorimeters allow considerable heat loss by refluxing on the cold upper surface of the sample container. Analysis of the exotherm itself can be carried out by determining temperature at which certain self-heat rates occur e.g. 0.1°C/min 0.2°C/min 0.5°C/min etc. These repeat to within 1-2°C. Also important to note is the maximum self-heat rate (though this can change with differences in void volume) the final temperature and the pressure rise. Unlike very many samples DTBP is completely reliable as a standard. The other way to analyse is to perform a ther-mokinetic analysis; the software can do this. There are very many literature reports of DTBP in toluene heat of decom-position and activation energy. These centre on a heat of reaction near 170KJ/mol and activation energy near 160KJ/ mol. Typically the Accelerating Rate Calorimeter working correctly will reproduce these values to ± 2-3%. Getting such results clearly indicates the quality of the techniques and the correct operation of the system in use. www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Real T al ime D eal T Time a eal Time Da ime D Data tta Plot Plo a Plot Plot: This shows the temperature against time for the complete test. In addition to showing the course of the experiment with time, the exothermic reaction temperature and magnitude of the reactions the data both before and after the exothermic reaction can be seen. At low temperature, reactions below the exothermic threshold may be noted and at higher temperatures the calibration accuracy of the instrument can be confirmed. By noting the pressure below the exotherm (and above) any indication of leak can be observed - or it may be that there is pressure generated from a non-exothermic process. (see previous page for examples) Temp emperat erature and Pres emperature and Pres emperatu u s re and Pres u s re Pl u o re Pl t ot: The temperature and pressure data are plotted against time to show the onset of reaction, the magnitude of the reaction and as a comparison it can be seen how much pressure is produced over which reaction or temperature range. It can be noted that much of the time of the reaction is in the first few degrees of temperature rise. (shown right) SSelf elf-Hea Heat R t R t ate Rate Pl te Plo Plot: The Self-Heat Rate is a key presentation of the results. The onset of reaction can be seen, as can the size, the magnitude, the complexity and number of reactions. The self-heat rate at any temperature is shown as is the maximum self-heat rate. By knowing the self-heat rate at an operating temperature for instance the amount of cooling required can he determined. By comparing the pressure rate with the self-heat rate further important information about the reaction can he obtained. (shown right) www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Pres res e ress ssure and Pres re and ure an Pres d P e and re Pressure R ssure re Rate Temperatu Rate Temperat te Temperatur ure Plots e Plots e Plots: Pressure Self-Heat R e H at R e a at R te An te A alysi alys s: Mathematical analysis of the self-may be plotted on linear axes or as logarithm of the pres-heat rate plot can determine heat of reaction, activation sure against reciprocal temperature (Kelvin). Should the energy and other kinetic parameters. The latter is carried data produce a linear plot on linear axes the pressure rise out by an automated curve fitting procedure. With the is that of a non-condensable gas, if the plot is linear on log-model result this may be used to back-extrapolate the reciprocal axes the pressure rise is likely to that due to va-data to get results below the onset of reaction, including pour pressure increase. In addition a plot of pressure rate time to maximum rate data from the modelled reaction at and against temperature rate may be produced, a straight low temperatures. line here indicates a single reaction - when heat is pro-Time to Maxi Time to Max mum R u a m R te: After selecting the temperature of maximum rate this important curve may be generated. With knowledge of f, the plot may be corrected to worst case. If the model reaction has been determined the time to maximum rate curve may be generated to lower temperatures. This presentation of data shows immediately the amount of time available from any temperature to runaway, possible disaster - in the worst case. The plot may also be used to determine maximum safe temperatures or size of storage vessels; the data may be used to determine SADT. www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Operations o Software The Set-up of a test is carried out by entry of information into user-friendly screens. This will include information on the sample and the bomb. All information entered here and data from the test result will link directly to the Microsoft Word Report that can be automatically generated after the test. It is possible to manually override the test conditions and run mode during the test. During the test the screen graphical user interface shows clearly the current status. The software can be networked such that the user can view run information remote from the instrument. www w . w thermalhazardtech c nol o og o y.c y om Accelerating Rate Calorimeter Vent Sizing THT’s Unique VSU (Vent Sizing Unit) utilizes DIERS technology to perform: Closed vessel, Tempering, and Blow-down tests. THT have experience in all aspects of process design and safety. The use of modern instrumentation and advanced software modelling allow THT to provide rapid and accurate themal safety assesment. Opt p ions and other products f s rom Thermal Hazard Technology: o Uniquely THT have developed the Accelerating Rate Calorimeter to extend its operation and usefulness: Low Phi, Vent Sizing, Cryogenic Operation, Sample Gas Collection, Sample Gas Safe Release, Sample Stirring and Dosing. THT have also developed the Battery Safety Calorimeter to allow use and abuse testing to be carried out with 1 instrument. System Specifications ystem Specifications: Sample sizes: mg-grams (>50g with low-phi test cell) Phi Range: 1.05 and higher Operating Temperature Range: Ambient - 500 °C (absolute max 600 °C) (Sub-zero with cryogenic option) Maximum Sensitivity: 0.005 °C/min (typical power equiva-THERMAL HAZARD TECHNOLOGY lent 30mW/g) Maximum Isothermal Stability (in Isothermal mode) 0.002°C 1 Nor 1 No t r h House o over 24 hours, onset detection from 0.002°C/min Bon Bo d n Aven Ave u n e Maximum Heat Rate (in Ramp mode) 10°C/min Ble Bl t e ch c ley e Pressure Limit 200bar (higher value transducers available) MK M 1 1SW 1 1S Mains Supply: Voltage: 100, 110, 120, 200, 220, 240 V AC / Phone: Ph 01908 6 01908 64680 01908 6 0 4680 Frequency: 50, 60 Hz / Power: 2.5 kW Fax Fa : x 01908 6 01908 64520 01908 6 9 4520 Cooling: Dry Air @ 2 - 10 bar (6 mm ID flexible tube) In Inf n o fo@ o th @therm r e m rm r alha haz a a zard r a d rd r te techno chno no chn lo logy gy gy g .com .co c m om .co www w . w thermalhazardtech c nol o og o y.c y om