Wang C.,Harbin Institute of Technology |
Wang C.,The Architecture Design and Research Institute of Guangdong Province |
Wei A.,China Urban Construction Design and Research Institute |
Wu H.,South China University of Technology |
And 4 more authors.
Chinese Journal of Chemical Engineering | Year: 2016
A numerical model was established to predict and optimise the chemical cleaning process of Polyvinylidene Fluoride (PVDF) Ultrafiltration (UF) membranes with the results from the experiment that applied the Response Surface Method (RSM) and Central Composite Design (CCD). The factors considered in the experimental design were sodium hydroxide (NaOH) concentration, sodium hypochlorite concentration (NaClO), citric acid concentration and cleaning duration. The interactions between the factors were investigated with the numerical model. Humic acid (20mg·L-1) was used as the model foulant, and chemical enhanced backflush (CEB) was employed to simulate the chemical cleaning process. The concentrations of sodium hydroxide, sodium hypochlorite, citric acid and cleaning duration tested during the experiments were in the range of 0.1%-0.3%, 100-300mg·L-1, 1%-3% and 0.5-1.5h, respectively. Among the variables, the sodium hypochlorite concentration and the cleaning duration showed a positive relationship involving the increased efficiency of the chemical cleaning. The chemical cleaning efficiency was hardly improved with increasing concentrations of sodium hydroxide. However, the data was sharply decreased when at a low level of sodium hydroxide concentration. In total, 54 sets of cleaning schemes with 80% to 100% cleaning efficiency were observed with the RSM model after calibration. © 2016 Elsevier B.V.
Chen G.,The Architecture Design and Research Institute of Guangdong Province |
Ou T.,The Architecture Design and Research Institute of Guangdong Province |
Li H.,The Architecture Design and Research Institute of Guangdong Province |
Liang J.,The Architecture Design and Research Institute of Guangdong Province |
Chen S.,The Architecture Design and Research Institute of Guangdong Province
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2010
The Billiards and Squash Synthetic Gymnasium for Asia Games of Guangzhou in a special structure with complicated features. The main structure is reinforced concrete frame with a large-span steel roof. The main structural supporting system is provided within the gymnasium with an inner box along with an external outer ring made with steel spatial truss, to effectively assure the continuity in force transfer of the roofing system. Tensile members are designed within the rooting system to enhance its stability. Through the analysis of dead load, live load, wind load, temperature and earthquake effects, it is found that the structure is not wind load sensitive, however dominated by earthquake loading, with some of the concrete-filled steel column bottom ends and a few frame at supports needing special attention. The temperature effect is very evident due to the large length, however, the temperature induced stresses can be reduced effectively with providing the expansion joint at middle of the structure.