scholarly journals The Combustion Characteristics of Waste Liquor from Renewable Plant-Derived Chemical Polyol Processing

2021 ◽  
Vol 27 (1) ◽  
pp. 103-110
Author(s):  
Dawei WANG ◽  
Guangbo ZHAO ◽  
Yuting LI ◽  
Yigang LUAN
Keyword(s):  
Weight Loss ◽  
Ignition Temperature ◽  
Inorganic Salt ◽  
Combustion Process ◽  
Frequency Factor ◽  
Vertical Tube ◽  
Tube Furnace ◽  
Waste Liquor ◽  
Vertical Tube Furnace ◽  
Peak Weight

An experimental study was carried out to investigate the combustion characteristics of plant-derived polyol liquor waste using thermogravimetric analyzer and vertical tube furnace tests. The research results showed that the waste liquor combustion reaction comprised four processes: evaporation, pyrolysis, combustion, and inorganic salt reaction, and that a wave peak exists for each process. The pyrolysis process, which is the most violent reaction, exhibited the maximum peak weight-loss rate and weight-loss ratio and had the lowest activation energy and frequency factor. The peak weight-loss rate of inorganic salt reaction process was less than that during the combustion process, but sodium alkali has catalytic effect at high temperature, which makes the activation energy and the frequency factor of inorganic salt reaction process less than that of the combustion process. The ignition temperature of the waste liquor in the vertical tube furnace was lower than the temperature in the thermogravimetric analyzer. The ignition temperature of pyrolysis volatiles measured in a vertical tube furnace was less than 700 °C but the ignition temperature of carbon combustion as measured with TG – DTG was 718 °C. When the temperature inside vertical tube furnace was higher than 800 °C, the waste liquor combustion process becomes almost instantaneous (about 8 s) and is violent, which produces more residual carbon content in the combustion products as a longer holding time is necessary to ensure that the reaction is completed.

The Effect of the Pyrolysis Furnace Type on the Yield of Silicon Carbide Whiskers Produced from Rice Husks

2011 ◽  
Vol 312-315 ◽  
pp. 346-351 ◽  
Author(s):  
Reza Eslami Farsani ◽  
Farshad Akhlaghi ◽  
Arman Sedghi
Keyword(s):  
Silicon Carbide ◽  
Maximum Yield ◽  
Horizontal Tube ◽  
Vertical Tube ◽  
Tube Furnace ◽  
Rice Husks ◽  
Silicon Carbide Whiskers ◽  
Pyrolysis Furnace ◽  
Vertical Tube Furnace ◽  
Lower Production

The production of silicon carbide whiskers (SiCw) by using rice husks has attracted a considerable attention due to a lower production cost as compared to the other processing routs. In the present investigation, the effect of pyrolysis furnace type (vertical tube, horizontal tube, and graphite chamber) on the yield of the resultant SiCw was investigated. It was concluded that the maximum yield was achieved by using a horizontal tube furnace whereas the minimum yield was obtained in a vertical tube furnace. These results were rationalized in terms of the different conditions for the evacuation of the produced gases from the different pyrolysis furnaces.

scholarly journals Use of colemanite in ferronickel smelting

2019 ◽  
Vol 55 (1) ◽  
pp. 1-8 ◽  
Author(s):  
E. Keskinkilic ◽  
S. Pournaderi ◽  
A. Geveci ◽  
Y.A. Topkaya
Keyword(s):  
Distribution Ratio ◽  
Vertical Tube ◽  
Metal Alloy ◽  
Copper Matte ◽  
Tube Furnace ◽  
Total Charge ◽  
Slag Volume ◽  
Vertical Tube Furnace ◽  
Matte Smelting ◽  
Very High

Use of colemanite in metal-slag systems aims primarily to decrease the viscosity of slag and, therefore, achieve better metal-slag separation. Enhanced metal-slag separation is helpful to decrease the number of suspended metal/alloy droplets in slag, i.e. the physical losses. In the literature, successful use of colemanite was reported both in steelmaking and copper matte smelting processes. Ferronickel smelting slags contain nickel in the range of 0.1-0.2% and correspondingly, metal-slag distribution ratio values of nickel are reported even above 200. On the contrary, nickel recoveries are hard to exceed 95%. This can be mostly attributed to the physical losses of nickel due to very high slag volume in ferronickel smelters; for 1 ton of ferronickel, 10-15 tonnes of slag are generated regardless of the type of the laterite, which contains significant quantity of gangue components. The authors thought that use of colemanite could be a solution to decrease physical losses. Therefore, the use of colemanite in ferronickel smelting was investigated in the present work. Laboratory-scale smelting experiments were conducted using calcined and prereduced laterites in a vertical tube furnace under different gas atmospheres. The amount of colemanite added was in the range of 0 - 2.5% of the total charge. The experiments were also performed using ferronickel and slag samples obtained from a ferronickel smelter.

Sign in / Sign up

Export Citation Format

Share Document