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A mathematical model of blast furnace operation, which is able to estimate the behaviors of the unburned char and the fine coke simultaneously, has been developed. The model based on the multi-fluid theory treats dynamic powders that are moving entrained by the gas stream as individual phases and static powders as solid components. The former takes conservation equations of momentum, thermal energy, chemical species and continuity. The latter takes only mass balance equations of chemical species, and shares fields of flow and temperature with the other solid components, such as lump coke, sinter, and so on. In the simulations, the unburned char is derived from the pulverized coal injected from the tuyere, and there is no difference in model treatment between the unburned char and the pulverized coal. The fine coke is generated uniformly in the raceway region from the coke particles, and the generation rate is determined by a kinetic treatment. The simulation of the blast furnace operation by this model revealed that the unburned char and the fine coke having different diameters and densities show different flow patterns especially in the cohesive zone and deadman. Consequently these two powders formed different areas of accumulation and reactions while large amount of powders were deposited in the deadman zone regardless of difference in flow patterns.

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With increase in pulverized coal injection rate to blast furnace, renewal behavior of deadman has been attracting much interests. This paper focuses on the renewal rate of the deadman induced by the sink-float motion of hearth coke bed, and it is discussed through cold-model experiments using half-cut model of blast furnace. Trajectories of packed particles in the deadman zone are converted into the transient velocity field, and further to the distribution of time required for particle transferring to the raceway zone. With this distribution the renewal rate of the deadman is quantitatively discussed. As the results, it is revealed that increase in the amount of accumulated water in the hearth, shallower hearth depth, and increase in gas flow rate make the discharging time of particles in the deadman zone shorter, and this tendency is explained by the height of sink-float motion of the hearth packed bed. About ten percent of particles that are discharged from the raceway passes through the deadman zone in the standard condition of this study. The particle movement induced by the sink-float motion of hearth packed bed is indispensable mechanism in the evaluation of deadman renewal.

Recycling organic of house waste remains fairly limited especially in urban area with low-and middle-income. A novel approach is developing method to manage the organic waste conversion using larvae Black Soldier Fly (BSF). The advantage of this approach links to the green technology waste management which is no pollutant effect to the environment as well as increase the added value economically. The research project successfully presented organic house waste conversion into high protein of animal feeding source. From the 5 dol of larva BSF’s (approximately 17 gr), it was reduced organic waste ± 0.7 kg/day. Within 10 days, the larva BSFs of 17 dol was consumed organic waste ± 10 kg, with increase their weight to become approximately 10 kg. The larva BSF of 17 dol is potential as animal feeding source that contain a high of protein. Furthermore, the waste from BSF’s cycle life is potentially to convert into chitosan, due to contain of chitin. Chitosan was produced from the waste of larvae skin, pupa skin and insect imago death. In general, this organic waste management is offering to green organic waste management in the future.