Classification and Disintegration Characteristics of the Carboniferous Rocks in Guangxi, China

To investigate the disintegration characteristics of the carbonaceous rocks in Guangxi Province, the typical carbonaceous rocks in the section exposed by the Hechi-Baise Expressway were investigated in this study. First, based on their mineral compositions and contents, the carbonaceous rocks were divided into four types: carbonate chert, carbonaceous argillaceous limestone, carbonaceous illite clay mudstone, and carbonaceous illite clay shale. Then, through indoor wet-dry cyclic disintegration test, the disintegration characteristics of the four types of rocks were studied. The test results showed the following: (1) the disintegration residues of the carbonate chert and the carbonaceous argillaceous limestone decrease linearly as the number of wetting-drying cycles increases. (2) The disintegration index of the carbonaceous illite clay mudstone and the carbonaceous illite clay shale decreases exponentially as the number of wetting-drying cycles increases. (3) As the number of wetting-drying cycles increases, the disintegration index curves of the carbonaceous illite clay mudstone and the carbonaceous illite clay shale samples gradually become stable until the disintegration of the samples is completed. (4) The disintegration of carbonaceous rocks is mainly affected by the clay content, followed by the structural form, but it cannot be ignored.

Effect of Basicity on Sintering Behavior and Metallurgical Properties of High-Chromium Vanadium-Titanium Magnetite

Basicity has an important effect on the behavior of high-chromium vanadium-titanium magnetite (HCVTM) sinter. The effect of basicity on sintering, reduction, and softening-melting properties was investigated in an experiment-scale sinter pot. The results showed that with the basicity increasing from 1.7 to 2.5, the vertical sinter speed, the productivity, the particle size, the reduction disintegration index (RDI), and the reducibility index (RI) increased. The yield increased first and then decreased, while the tumble index (TI) had the opposite trend. The perovskite content increased first and then stabilized, and the silico-ferrite of calcium and aluminum (SFCA) increased from the basicity of 2.3. The HCVTM sinter had a better tendency of the softening behavior with the basicity increase. In addition, the melt droplet comprehensive index S increased, which indicated that the increase in basicity negatively affected the droplet performance. As the basicity increased, the comprehensive index value increased. Considering the adverse effect of basicity on softening-melting properties, the best recommended value is 2.3.

Effect of High Voltage Electrical Pulses on the Oil Yield of Sunflower Meal

Introduction. One of the most important tasks of the modern oil and cake industry is to develop advanced technologies that could increase the yield of high quality oil and related target components from oilseeds. Study objects and methods. The present research featured sunflower oilseeds. The main method of electrical treatment processing was high-voltage electrical pulses of microsecond duration: electric field strength = 13.3 kV/cm, frequency = 30 Hz. To assess the effects of electric pulses, we used disintegration index, i.e. a method of determining the number of destroyed cells according to the electrical conductivity of the material. To assess the effect of the treatment, the sunflower meal was pressed in a hydraulic press. The procedure was followed by extraction using hydrocarbon solvent. As an additional assessment, we analyzed the biomass impedance before and after treatment with high-voltage discharges with the determination of the disintegration index. To assess the quality of the resulting oil, we determined the acid and peroxide values. IR spectroscopy provided a more thorough assessment of the quality of the oil. Results and discussion. After the sunflower meal was treated with high-voltage pulses, the yield of pressed oil increased by 1.9%. The residual oil content in the meal fell down to 0.61% compared with 1.19% in the control samples. Oil quality indicators showed that treatment with high-voltage pulses did not significantly affect the acid value. The sudden change in the peroxide number was probably caused by the prolonged heating during the experiment. Conclusion. The obtained experimental data made it possible to forecast the prospects of using the high-voltage electric pulse for oilseed processing and assess the effectiveness of the technology together with its prospective industrial use. The alternative technology can replace the stage of crushing and pre-heating.

The Use of Disintegration Ratio in Evaluating Rock Durability in Selected Mudrock Samples in Indonesia

Characterization of durability of mudrocks is important regarding its slaking behaviour within a short time when exposed to and or interact with water. Some relevant cases that occurred due to slaking are damage to roads and slope failures along the Cipularang and Cipali Toll Road. Current engineering activities related to the presence of mudrocks are being and will be held in several locations in Indonesia such as the construction of the Cisumdawu Toll Road in Ujungjaya District, Sumedang and building the National Observatory in Timau District, Kupang. This research is useful for providing engineering considerations related to those activities. The methods used in this research included X-ray diffraction to obtain mineralogy of mudrock, laboratory testing of physical properties of rocks such as dry density, water content, porosity, absorption and mudrocks durability tests. Durability of rocks was determined by disintegration index test. Testing was carried out by wetting and drying of rock samples. Test results showed that the average disintegration ratio of claystones, shales, mudstones and siltstones are 0.1035, 0.2183, 0.4942 and 0.9900. Slaking mode occurs to claystones, mudstones and shales is body slaking while dispersion slaking occurs to siltstones. Evaluation of the durability of mudrocks in this research indicates that siltstones have the highest durability characterized by very slow disintegration, followed by mudstones, shales and claystones at the lowest with very quick disintegration. Disintegration ratio from the disintegration index test characterizes the durability of mudrocks in more details. It can be concluded that porosity and absorption are incorporated into the main factors affecting the durability of mudrocks.

Electrohydrodynamic Drying of Chinese Wolfberry in a Multiple Needle-to-Plate Electrode System

In order to systematically and comprehensively investigate electrohydrodynamic (EHD) drying characteristics and mechanisms in a multiple needle-to-plate electrode system, drying experiments of Chinese wolfberry were conducted by blocking ionic wind and changing needle spacing in a multiple needle-to-plate electrode system. Drying characteristics, quality parameters, and the microstructure of Chinese wolfberry fruits were measured. Results show that ionic wind plays a very important role during the drying process. Drying rates of different needle spacing treatments are significantly higher than that of the control, and the drying rate decreases with the increase of needle spacing. Needle spacing has a great influence on the speed of ionic wind, rehydration rate, and polysaccharide contents. The effective moisture diffusion coefficient and the electrical conductivity disintegration index decreases with an increase in needle spacing. Ionic wind has a great influence on the effective moisture diffusion coefficient and the electrical conductivity disintegration index of Chinese wolfberry fruits. The microstructure of Chinese wolfberry fruits dried in an EHD system significantly changed. This study provides a theoretical basis and practical guidance for understanding characteristic parameters and mechanisms of EHD drying technology.