Advanced Materials Research Vols. 113-116

Abstract: Depending on the analysis of the phase composition of red mud, particle distribution, distribution of reusable iron was studied clearly which size must above 360 mesh and verified by experiments. The revealed regular pattern of reusable red mud reduces the cost of the red mud processing costs. Then the rest of the distribution of iron in red mud were studied by flotation which is not the effective methold.Study provides a economic way to use red mud reused as secondary resources.

Abstract: In this study, a new method (negative pressure cavitation method, NPC) for metal ions removal from industry waste water has been studied. Under the identical adsorption conditions，we have seen some different effects among static adsorption, shaking adsorption and NPC adsorption. The results are as following: four kind metal ions showed the accordant phenomenon that the sequence of adsorption capacity is NPC adsorption>shaking adsorption>static adsorption. The different metal ions have different improvement of removal ratio. The sequence is Cd>Hg>Pb>Cu. The intercellular pH of absorbed yeast cells increased with the adsorption process from acidic to alkaline. These may suggest that the Candida utilis has certain resistance against heavy metals. The increased pH is also an environment stress response of Candida utilis. So NPC adsorption may have potential values to removal of metal ions.

Abstract: The paper studied effect of blast-furnace slag on rheology and hydration properties of blended cement paste. Rheology of blended cement paste with polycarboxylic series (PCS) and sulphamate series (SMS) superplasticizer is tested, appraised effect degree of the dosage and fineness of slag in blended cement by saturation dosage of superplasticizer, fluidity and gradual loss of fluidity. For hardened paste, the study tested development of strength and hydration products, activation effects of gypsum and sodium sulfate, analyzed macro mechanical behavior and micro structure of blend cement made from slag.

Abstract: In order to achieve a sustainable development of aluminum industry, aluminum flow analysis for the life cycle of aluminum products in China was necessary. Aluminum flow in the aluminum products life cycle of 2003-2007 in China has been analyzed, from which the following data were resulted. Resources self-support ratio in alumina production, aluminum production and the aluminum industry dropped, increased and leveled off in the period 2003-2007, respectively. Self-produced aluminum scrap use ratio was in the range 5-7%, and the situation of the aluminum scrap lacking state can’t be settled in case of fast increment of aluminum production. Proposals for the sustainable development of aluminum industry in China were put forward.

Abstract: Drained sludge of Daqing oilfield No.4 oil production plant was collected from bottoms of tanks, and the oil content was usually lower than 2%. In this paper, the contents of petroleum substances, total petroleum hydrocarbons (TPH) and animal and plant oil were investigated. Ultrasound-UV method was used to detect the oil content of oily sludge. Results showed that the best ultrasound time was 8 min and the best solid-liquid ratio for the extraction was about 1:20. The standard curve was constructed. The comparison between the ultrasound-UV method and the traditional method shows that the ultrasound-UV method is more suitable for the detection of oil content of oily sludge with lesser oil. Moreover, the methods of detecting sludge with lower oil content have been established.

Abstract: The objective of this paper is to apply the wood-based composite materials into the field of intelligent decorative materials or wooden crafts materials, and then improve people's life quality in the micro-environment. We introduce photochromic materials and the micro-capsule technology, and bring them into the processing field of wood-based composite materials, which make us find a new thinking direction for high value-added wood-based products. So that wood will be efficient and rational use of meeting demands of domestic and international market for intelligent and environment-friendly high-grade raw materials.

Abstract: In this paper, a series of lab-scale experiments have been focused on the zinc recovery from electric arc furnace (EAF) dust by alkaline extraction, combining with the novel alkaline zinc electrowinning technology. Effects of several leaching variables, i.e. leaching time (1-3 h), NaOH concentration (150-400 g/L), solid/liquid ratio (S/L, 1/5-1/12), temperature (30-90 °C) and stirring speed (300-500 rpm) on zinc recovery (%) were investigated. Around 84 %Zn and 92 % Pb were respectively recovered when the leaching process was operated with 250 g/L NaOH and S/L 1/10 at 90 °C for 2 h. After Pb was selectively removed by sodium sulfide precipitation, the alkaline zinc solution was subjected to electrolysis and zinc powder with a purity of 98.5 % was then obtained. The leaching residue is suitable for safe disposal, while the purifying residue can be marketed for lead recovering.

Abstract: Acclimation of short-cut nitrification aerobic granular sludge with aerobic granular sludge and nitrification sludge as seed sludge in a sequencing batch reactor(SBR) by controlling the pH, influent ammonia concentration, temperature and other conditions. Experimental results showed that the short-cut nitrification aerobic granular sludge with high ammonia and COD removal rate (95%) was formed successfully, and SBR can run long-term stably. DO at 6.0~8.0mg/L when the nitrosation rate remained stable at 50% ~ 60%, and lower DO levels within the reactor (2.0~3.0mg/L) nitrosation rates of up to 90%. Mature short-cut nitrification aerobic granular sludge average diameter of 2~3mm in between, MLSS of up to 10.162g/L, SVI minimum up to 22.63ml/g, moisture content is only 81.93%, total nitrogen removal rate of 40%, and carbon-nitrogen removal capability.

Abstract: Laboratory-scale tests for removal and recovery of nitrogen and phosphorus in human urine were conducted by magnesium ammonium phosphate precipitation (MAP) method. Proper Na2HPO4•12H2O as a phosphorus source and MgCl2•6H2O as a magnesium source were added to adjust the ratio of Mg2+, NH4+and PO43-. The effects of initial pH, (Mg2+): n (NH4+), n (PO43-) : n (NH4+), temperature, reaction time and stirring speed on removal and recovery of nitrogen and phosphorus in urine were studied by MAP method. Results showed that the optimum experimental conditions were at room temperature, pH, the molar ratio of Mg2+：PO43-：NH4+, reaction time and stirring speed were set 10, 1.2:1:0.9, 30min and 100r/min.

Abstract: This study was to evaluate the use of green waste compost (GWC) as a growth media for rooting of Impatiens hawkeri. The experiments were divided into two sections. In the first experiment, GWC samples were collected periodically during a 60-d rapid composting period from a single windrow. A germination test was carried out previously in order to evaluate the phytotoxicity presence of GWC using Lepidium sativum L. (cress) as an indicator. Subsequently, five growth media were prepared containing 100%, 75%, 50% and 25% by volume of GWC with the corresponding peat as diluents, plus an untreated control (0 %). The same cuttings of Impatiens hawkeri were selected and potted into plugs. The germination tests showed that 45 days after rapid composting GWC could be considered to be mature. It was therefore concluded that GWC could be successfully used as a good adjuvant for peat substitutes for cutting propagation of Impatiens hawkeri in quantities of 25-50% by volume.