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Production of electrolytic manganese metal inevitably produces a certain amount of solid wasteelectrolytic manganese anode slime, with a high manganese content, but its difficult to recycle due to the presence of other impurities. Firstly, the washing method was used to remove the anode slime soluble salts, then its chemical composition and phase were analyzed. The flame atomic absorption spectrometer and X-ray fluorescence (XRF) analysis showed the anode slime mainly contained Mn, Pb, Ca, Fe, Cr, K, Se and other metal elements, with the average manganese content 45% and the lead 3.5%;X-ray diffraction (XRD) preliminary analysis showed that the anode slime was a colloidal system mainly containing the spinel structure of MnO2 and complex salts PbMn8O16xH2O phase, by high temperature roasting, the anode slime transformed from hexagonal system to cubic system , and the basic structure unit from edges connection to surfaces connection,the change of length,angle and fracture of manganese-oxygen bond provided the channel for the lead leaching;TG-DTA analysis showed that anode slime was dominated by water loss below 400°C,and started to lose oxygen beyond 425°C, and clear endothermic peak was observed at 500°C and 700°C, which showed the anode slime crystal structure changed at 500°C, anode slime weight loss tending to be gentle with some Mn2O3 generation at 700°C, and roasted crystal stabilizing to Mn2O3. Preliminary roasting and leaching purification technology route was proposed according to the above analysis results, and analysis of the purification process related factors was made. Under the condition of natural ventilation, anode slime was roasted at 700°C, and fully leached in 2mol/L HAc , with liquid-solid ratio 10:1, then leached anode slime was characterized by XRD and flame atomic absorption test, the results showed that anode slime manganese content increased from 45% to 67.5%, the lead content decreased from 3.5% to 0.1%, XRD indicated that the anode slime existing phase was Mn2O3. Anode slime after purification treatment can be further used for battery manganese source material, which provides an effective approach for the recovery of manganese anode slime utilization.

A large number of Chinese herbs residues were produced during the production of honeysuckle and midday tea. Usually, the content of organic components in the residues was at a high level. These residues would pose a great threat to the local water environment, if they were not treated and disposed properly. In this paper, a self-prepared anaerobic reactor was utilized to treat the residues of honeysuckle and midday tea in semi-solid phase media. The anaerobic sludge was inoculated into the residues for anaerobic digestion at the temperature of 37±1°C, and ISRs (ISRs is the total solid mass ratio between inoculum and substrate) were 1:2, 1:1, 2:1 respectively. The result showed that the ultimate maximum yield of methane was the under ISRs of 1:1, the cumulative methane production volume of honeysuckle and midday tea dregs were 5832mL/100g and 5591mL/100g, respectively, after 192h digestion. Under the best inoculation ratio of 1:1, another mesophilic anaerobic experiment was carried out by mixing the residues of honeysuckle and midday tea as substrate at different ratios of 0:3, 1:2, 1:1, 2:1 and 3:0, respectively, which were to compare the methane production at 37±1°C. The result indicated that the ultimate maximum yield of methane was under mixed ratio of 1:2, the cumulative methane production volume of the mixed Chinese herbs residues was 9110 mL/100g after 192h digestion. Furthermore, the zero-order kinetic model was found to be suitable to characterize the removal ratio of substrate during 0~108h digestion while the biogas was generated fast, and the kinetic constant k was 50.49mL/h. To obtain the ultimate maximum rate of methane production, the anaerobic reaction should be controlled under the stage of zero-order reaction. Thus, the experimental results could provide scientific proof for anaerobic treatment and methane recycling in organic waste of Chinese herbs enterprises.

Building an index system of circular economy evaluation scientifically, evaluating the state of development of circular economy correctly, is not only main contents of the circular economy research, but also an important way to achieve the sustainable development of circular economy. Based on promulgated by the government, combined with the actual development of Ningbo's circular economy, a comprehensive evaluation index system of Ningbo's circular economy development has been built. And therefore the state of circular economy development from 2001 to 2011 has been evaluated dynamically. (2013) Trans Tech Publications, Switzerland.

Considerable research effort has been reported in cost-optimal operation of heat exchanger network. However, most of them neglect the pressure drop influence and assume constant film heat transfer coefficients. Pressure drop of streams are important influencing factors for the performance of heat exchanger network operation. In this paper, a general cost-optimal operation model considering pressure drop constraints and removing the assumption of constant film heat transfer coefficients is proposed. It is necessary to determine the pumping power cost required as part of operating cost function. The extended model is applied to one example taken from previous research, and the results prove that the proposed method can obtain more real optimization results for HEN operational optimization problems.

Collapse of crowm broked out with large water gushing at working face during driving tunnel in Ming Ya Zi tunnel’s right tube. According to engineering geology condition and analysis of causes of collapse, double-deck prior ductile grouting reinforcement technique was applied in tunneling surrounding rock consolidation based on the strong pre-support theory.And the result of treatment was successful.Thus,guiding the work of tunnel collapse treatment by strong pre-support theory was proved reasonably and effectively.

As a raw material, Indonesia vanadium-titanium sinters are being applied to the blast furnace process for iron making in the typical iron and steel plant. In order to keep the health running of blast furnace process, in this work we have investigated the softening and melting properties of Indonesia vanadium-titanium sinters. We found that the content of vanadium-titanium magnetite in sinter is correlated with the softening and melting ranges for those sinters considered here. With the increasing of the vanadium-titanium magnetite in sinter, the starting softening temperature increases gradually and the final softening temperature increases as well, thereby the softening range becomes narrow. Both starting and final melting temperatures begin to ascent, and the variation of melting range is not obvious. In addition, we also found that the coke is wetted by the molten slag and iron. From the viewpoint of blast furnace process, the softening and melting zone has to move downward. In this zone of blast furnace the contact area of solid-liquid phase will get larger because of the close contract among the molten slag, iron and coke. On one hand, this kind of behavior can definitely speed up the reduction of iron oxide. On the other hand, it simultaneously worse the ventilation properties and affect the normal running of air flow, because a lot of iron and slag can not be got smoothly into the hearth through coke layer.