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Combined with a low temperature methanol wash unit tower equipment lifting practice, analysis the integral lifting method of large equipment selection, process route establish and lifting machines and tools selection and lifting scheme optimization, and points out that the heavy machinery used in large equipment lifting is the direction of future development.

The modal analysis of composite thin-walled box beams with double-cell sections is carried out by the finite element software ANSYS. The finite element models are established first for the double-cell composite thin-walled box beams, then the vibration modes of two box beams: Circumferentially Uniform Stiffness (CUS) and Circumferentially Antisymmetric Stiffness (CAS) are calculated and analyzed. The effects of length-width ratio and width-height ratio on the natural frequency and the modal shape of the double-cell composite thin-walled box beams are discussed.

Taking example for U-shape sheet metal, the paper studies the forming and springback process with Dynaform, how much the springback influenced by several factors is studied, including die figure, stamping velocity, the stroke, the blank holder force and friction. Then a useful conclusion can be reached: Using die figure to optimize the technological parameters remarkably reduce the springback value, it provides a new method to control and solve the springback issue.

In this paper, with the help of program Thufiber, fiber model is used to simulate bridge piers, solid element is used to simulate the superstructure in program MSC.Marc. The effects of the travelling wave on the nonlinear seismic response of the long-span continuous rigid-frame bridge with high piers are analyzed under 2008 Wenchuan Earthquake Wave excitation. The results show that travelling wave has much effect on displacement and shear force of high piers of the bridge. The displacement of the pier top decreases 20% to 50% and the shear force at the pier base increases from 20% to 30%.

For environmental conservation, resource saving and sustainable development, discarded concrete sources are introduced and current situation of its application is summarized. Then, the facing problems and solutions on concrete-recycling use are analyzed, and recycled application methods of discarded concrete are proposed.

A new inorganic-organic composite dual-coagulant (PAFC-CPAM) was prepared by polyaluminum ferric chloride (PAFC) and cationic polyacrylamide (CPAM) and its treatment efficiency for oily wastewater was evaluated by coagulation jar tests. PAFC-CPAM dual-coagulants were characterized by FT-infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The FTIR spectra illustrated that there were some chemical reactions between PAFC and CPAM in PAFC-CPAM. SEM micrographs testified that PAFC-CPAM formed compact net structure which is different from PAFC and CPAM, resulting to its outstanding coagulation performance other than monomeric coagulant in treating oily wastewater. Coagulation jar tests presented that PAFC-CPAM improved 1.14% and 0.38% of oil removal rate and reduced 0.35NTU and 0.06NTU of residual turbidity than PAFC and CPAM respectively at the optimal dosage of 120mg/L. PAFC-CPAM enhanced 4.56% and 2.12% of oil removal efficiency and decreased 0.27NTU and 0.01NTU of residual turbidity on average in comparison with PAFC and CPAM respectively in the pH range of 4.0-8.0. All of above-mentioned experiment results demonstrated that PAFC-CPAM behaved superior coagulation performance than PAFC and CPAM.

Based on the pretreatment including acidification, purification and sodium ion exchange, the crude sepiolite was modified by microwave radiation-wet process and CTAB as modifier. The orthogonal experiment was used to optimize the modification process. Then the crude sepiolite and modified sepiolite were characterized by SEM, FTIR, XRD, TG-DSC and BET. The results showed that the optimum modification process parameters included CTAB dosage (1.0 cation exchange capacity (CEC)), microwave radiation time (4 minutes), ethanol concentration (50%/V:V) and radiation power (800W). Compared with crude sepiolite, oil removal rate from steel rolling wastewater increased from 41.34% to 96.78% with modified sepiolite prepared at the best process. Characteristic peaks of organic functional groups, enlarged interlayer distance (0.007nm larger than crude sepiolite), enhanced hydrophobicity, amplified specific surface area (104.4m2/g) and mesopore volume had been received from above characterization methods after modification. All of the above had proved that CTAB was successfully grafted onto sepiolite.

The aim of the present work is to obtain iron-oxide coated porous ceramics filter (IOCPCF) via dip-coating and test its adsorption and degradation for methylene blue (MB). Porous ceramics filter (PCF) and ferric nitrate were used as substrate and modifier respectively. IOCPCF was characterized by spectrophotometer, X-ray diffraction, scanning electron microscopy, specific analyzer and Fourier transform infrared spectroscopy. The effect of its structure and performance on adsorption and degradation of MB aqueous solution was investigated. The results indicated that the average pore diameter, specific surface area and porosity of IOCPCF were 11.36 nm, 4.987 m2/g and 58.63% respectively. The major crystalline phase of iron coat was α-Fe2O3 which took on porous framework. Using the prepared material, the decoloration conversion for MB aqueous solution can reach 72.06% in 300min and be increased by 21.59% compared with original PCF.