scholarly journals DB Construction of Activation Temperature and Response Time Index for Domestic Fixed-temperature Heat Detectors in Ceiling Jet Flow

2020 ◽  
Vol 34 (3) ◽  
pp. 35-42 ◽  
Author(s):  
Ga-Yeong Yoon ◽  
Ho-Sik Han ◽  
Sun-Yeo Mun ◽  
Chung-Hwa Park ◽  
Cheol-Hong Hwang

The accurate prediction of fire detector activation time is required to ensure the reliability of fire modeling during the safety assessment of performance-based fire safety design. The main objective of this study is to determine the activation temperature and the response time index (RTI) of a fixed heat detector, which are the main input factors of a fixed-temperature heat detector applied to the fire dynamics simulator (FDS), a typical fire model. Therefore, a fire detector evaluator, which is a fire detector experimental apparatus, was applied, and 10 types of domestic fixed-temperature heat detectors were selected through a product recognition survey. It was found that there were significant differences in the activation temperature and RTI among the detectors. Additionally, the detector activation time of the FDS with the measured DB can be predicted more accurately. Finally, the DB of the activation temperature and RTI of the fixed-temperature heat detectors with reliability was provided.

2014 ◽  
Vol 28 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Hee-Won Park ◽  
Jae-Ho Cho ◽  
Sun-Yeo Mun ◽  
Chung-Hwa Park ◽  
Cheol-Hong Hwang ◽  
...  

2012 ◽  
Vol 184-185 ◽  
pp. 1110-1113 ◽  
Author(s):  
Li Fen He ◽  
Qi Xia Liu ◽  
Tao Ji ◽  
Qiang Gao

Various jute-based activated carbon fibers were prepared by using jute fibers as raw materials and phosphoric acid as activating agent. The effects of three main factors such as concentration of activating agent, activation temperature and activation time on the yield and adsorptive properties of active carbon fibers were investigated via orthogonal experiments. The surface physical morphology of jute-based activated carbon fiber was also observed by using Scanning Electron Microscope. Results showed that the optimum conditions were phosphoric acid concentration of 4 mol/L, activation temperature of 600 °C and activation time of 1h. The yield, iodine number and amount of methylene blue adsorption of the active carbon fiber prepared under optimum conditions were 37.99 %, 1208.87 mg/g and 374.65 mg/g, respectively.


2013 ◽  
Vol 68 (7) ◽  
pp. 1503-1511 ◽  
Author(s):  
J. M. Salman ◽  
F. M. Abid

Palm-date pits were used to prepare activated carbon by physiochemical activation method, which consisted of potassium hydroxide (KOH) treatment and carbon dioxide (CO2) gasification. The effects of variable parameters, activation temperature, activation time and chemical impregnation ratios (KOH: char by weight) on the preparation of activated carbon and for removal of pesticides: bentazon, carbofuran and 2,4-dichlorophenoxyacetic acid (2,4-D) were investigated. Based on the central composite design (CCD), two factor interaction (2FI) and quadratic models were respectively employed to correlate the effect of variable parameters on the preparation of activated carbon used for removal of pesticides with carbon yield. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The optimum conditions for preparing activated carbon from palm-date pits were found to be: activation temperature of 850 °C, activation time of 3 h and chemical impregnation ratio of 3.75, which resulted in an activated carbon yield of 19.5% and bentazon, carbofuran, and 2,4-D removal of 84, 83, and 93%, respectively.


2016 ◽  
Vol 878 ◽  
pp. 101-107
Author(s):  
Guo Zhuo Gong ◽  
Ji Liu ◽  
Wen Fen Yang ◽  
Yun Yun Zhou ◽  
Hai Tao Sheng ◽  
...  

In the paper, a series of coal-based columnar activated carbons (CCACs) for adsorption of benzene were prepared using a factorial experiment method. The CCACs prepared were characterized, and their adsorption capacities toward benzene were measured in a differential fixed-bed reactor. Besides, through a statistical method, the importance degree of preparation variables was studied, and the effects of preparation variables on benzene adsorption capacities of the CCACs were fully evaluated. It was found that pore structure of CCACs prepared was beneficial for benzene adsorption, but preparation variable in the process has little effect on the surface chemistry of CCACs prepared. Based on statistic analysis, it was revealed that among the four process variables studied for the sorbent prepared in this work, the activation temperature was found to be the most significant one for benzene adsorption capacity, next ones are the activation time and the amount of KOH, and the last one is the flow rate of water vapor and their optimal levels were 950 °C, 3.0 h, 2.5 % and 1.25 mL/g/h respectively.


2013 ◽  
Vol 864-867 ◽  
pp. 1694-1698 ◽  
Author(s):  
Lin Zhi Zhai ◽  
Gang Li

Peanut shell-based activated carbon was prepared by 60% zinc chloride activation. The activation temperature was 923K and activation time was 90min. The activated carbon was applied on the removal of acid light yellow from wastewater. The effects of the amount of adsorbent, the initial dye concentration and pH value of solution were investigated. The results showed that the optimum conditions for dye removal: activated carbon dosage of 2.5g/L, initial dye concentration of 50mg/L, pH value of 3. The color removal efficiency attained above 95%. It is concluded that activated carbon developed from peanut shell could be effective and practical for utilizing in dye wastewater treatment.


2021 ◽  
Vol 11 (5) ◽  
pp. 12662-12679

In this study, Chemical activation was used to prepare a low-cost activated carbon (AC) from agricultural waste material: Cucumis melo. It was used as a green biosorbent for the removal of cationic and anionic dyes from aqueous solutions (Methylene blue (MB) and Acid orange 7 (AO7)).A full factorial 24 experimental design was used to optimize the preparation conditions. The factors and levels included are activation temperature (300 and 500ºC), activation time (1 and 3 h), H3PO4 concentration (1.5 and 2.5 mol/L), and contact time (60 and 90 min). The surface area of the activated carbons and high removal efficiency of MB and AO7 was chosen as a measure of the optimization. The activated carbon prepared at 500 °C, for 3 hours with an H3PO4 concentration of 2.5 mol/L and a contact time of 90 min, have the largest specific surface area (475 m2/g) and the percentage of discoloration of methylene blue (99.4%). Furthermore, the greater value of AO7 removal (94.20%) was obtained at 3h - activation time, 500°C - activation temperature, 1.5 mol/L - H3PO4 concentration with a 90 min contact time.


2021 ◽  
Vol 2079 (1) ◽  
pp. 012006
Author(s):  
Junxin Zhang ◽  
Xiumei Duan

Abstract Using fly ash from a thermal power plant in Yingkou City as raw material, The inorganic polymer flocculant polyaluminum ferric chloride (PAFC) was prepared by sodium carbonate impregnation, high temperature roasting activation, and acid leaching. The influence of activation temperature and activation time on the leaching of aluminum and iron was investigated through single factor test and orthogonal test. The PAFC preparation conditions were optimized, and the prepared PAFC flocculant product was applied to kaolin turbidity water. The test results showed that the content of aluminum in fly ash was 7.08%, and the content of iron was 4.95%. The mass ratio of the activator sodium carbonate and fly ash was 10:7, the activation temperature was 800°C, and the activation time was 2h. The leaching rates of aluminum and iron were the highest, 88.31% and 53.66% respectively. The optimal conditions for the preparation of the flocculant were as follows: the molar ratio of aluminum to iron was 5.7:1, and the reaction time was 1.5h. The liquid product obtained under these conditions was yellowish brown, and the solid product obtained after being dried was yellow powder.


BioResources ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 1333-1346 ◽  
Author(s):  
Zhenwei Yu ◽  
Qi Gao ◽  
Yue Zhang ◽  
Dandan Wang ◽  
Innocent Nyalala ◽  
...  

Sludge-based activated carbon (SAC) was prepared with sewage sludge and Chinese medicine herbal residues (CMHR’s). An orthogonal experimental design method was used to determine the optimum preparation conditions. The effects of the impregnation ratio, activation temperature, activation time, and addition ratio of CMHR’s on the iodine value and Brunauer-Emmett-Teller surface area of activated carbon were studied. X-ray diffraction, Fourier-transform infrared spectrometer, and scanning electron microscopy were used to characterize the prepared SAC. The results showed that the optimal process conditions for preparing the SAC were as follows: an impregnation ratio of 1:4, an activation time of 30 min, an activation temperature of 700 °C, and an addition ratio of CMHR’s of 40%. The adsorption balance of the methylene blue dye was examined at room temperature. Adsorption isotherms were obtained by fitting the data using the Langmuir and Freundlich models, which showed that methylene blue adsorption was most suitable for the Langmuir equation. The results demonstrated that SAC prepared from SS and CMHR’s from a Chinese medicine factory could effectively expel dyes from wastewater.


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