Advanced Materials Research Vols. 1073-1076

Abstract: Azithromycin wastewater has high ammonia, high COD and high salt content characteristics. By ammonia stripping-Fenton oxidation pretreatment of azithromycin wastewater, the effect is obvious. The optimum technological conditions are determined by experiments, the effluent COD can be reduced to 5000mg/L or less, the total removal of up to 85.6%. After pretreatment of wastewater, the BOD₅/COD value was increased from 0.12 to 0.38, and the biodegradability of the wastewater was improved.

Abstract: Rice husk was used as an adsorbent to study the adsorption of Cr (VI) from wastewater, Based on the experimental studies on influences of the particle size of rice husk, solution pH value, adsorption time, temperature and rice husk dose, the optimal conditions of the adsorption were determined as follows: temperature of 35°C, pH of 2, the particle size of rice husk in the range of 80-100 mesh, adsorption time of 3h, dose of 30g/0.2g. Under the optimal conditions, the removal rate of chromium from wastewater by rice husk can reach 91%.

Abstract: Agriculture is one of the foundations of China’s national economy. The rural population is more than half of China’s total population. However, rural domestic wastewater treatment has not been solved, mostly household wastewater untreated directly discharged into nearby surface water bodies. With the development of rural economy, domestic wastewater treatment has become a serious problem in rural sustainable development in China. Emission characteristics and status of rural domestic wastewater treatment in China were presented in this paper. On this basis, several rural wastewater treatment technologies commonly used were reviewed in China rural area, including septic tanks, land treatment system, methane-generating pit, stabilization lagoon and constructed wetland. The current problems and future development in rural domestic wastewater treatment were discussed, and some suggestions proposed. On the one hand, new integrated technology should be actively developed in rural domestic wastewater. On the other hand, the management of rural domestic wastewater should be strengthened. Thus, effective protection will be provided for the sustainable development of rural areas in China.

Abstract: The sulfide tailings is the main type of non-ferrous metals mine tailings, in which the sulfides could react with air, rain water and microorganism, etc. and then release some ions through a series of complex chemical interactions. The heavy metal ions leaching from tailings will cause serious pollution to the environment of mine region. The release mechanisms and effect factors of heavy metals ions from sulfide tailings are summarized in this paper.

Abstract: The basalt fiber is a new kind of high-performance environmental material, which has aroused widespread concern in recent years. Although it has been preliminary applied in construction, aerospace, national defense, petrochemical and other fields, there is few study in the field of environmental protection, especially in the water pollution control. This paper summarized the characteristics of basalt fiber and introduces the technology application programs in the centralized sewage water treatment, natural water body purification and as a catalyst carrier material used in the wastewater treatment. In order to enable basalt fiber to obtain further application in the area of water pollution control, correlated suggestions were put forward at the end of this article.

Abstract: Nitrous oxide is a greenhouse gas, and biological nitrogen removal leads to nitrous oxide generation and emissions. In this study, the emission of nitrous oxide from partial nitrification process was investigated in two intermittently aerated SBRs (IASBRs). Activated sludge floc and aerobic granular sludge were feed into two IASBRs, respectively. In the steady state, partial nitrification was successfully achieved under intermittent aeration control strategy. Nitrous oxide emissions were 6.5% and 8.9% of the total influent nitrogen loading rate in IASBR1 and IASBR2, respectively. Nitrous oxide was mainly generated in non-aeration periods, but aeration period contributed to 91.8% and 90.6% of nitrous oxide emissions in two IASBRs, respectively. PHB can be used as the carbon source for heterotrophic denitrification, causing more nitrous oxide generated in IASBR2 which was seeded with aerobic granular sludge.

Abstract: A waste water treatment plant (WWTP) adopts sequencing batch reactor (SBR) process, which exist the problem of instable treatment effect on denitrification and dephosphorization. The total nitrogen (TN) and total phosphorus (TP) of the effluent could not reach the class A standard of discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002) (hereinafter referred to as the class A standard) as a result of different order in utilizing the carbon source between nitrification and denitrification. The step-feed procedure is used to improve the efficiency of denitrification and dephosphorization. Field experiments about the effects of the different influent distribution ratio (marked as λ) on denitrification and dephosphorization were carried out and the results showed that the effect of the effluent TN is the best and other indexes could also achieve class A standard when λ is 5:3.

Abstract: In order to improve the effect of meta-aramid on filtering fine dust particles such as PM2.5, the fineness of the fine denier meta-aramid was discretized, and new differential fiber was obtained. According to the results, this filter medium was superior to conventional 2.2 dtex samples in terms of classified filtration and caused a more significant effect on collecting fine dust particles; the initial resistance remained unchanged roughly; and the air permeability could reach 279 L/(m²•s), demonstrating that this filter medium has a great advantage in filtration efficiency as well as energy conservation and emission reduction.

Abstract: The characteristics of the P removal sludge were studied in 3 different operation modes (AO, AOA and A²O mode) of the sequencing batch membrane reactor (SBMBRs). The results showed that the sludge P content was positively correlated with the P removal ability. The relative P content of the saturated P uptake sludge was 30.6%, 36.7% and 42.9%, respectively in the 3 modes. PHB was synthesized in anaerobic activated sludge and the polyp-P granules were decreased. The opposite trend appeared in aerobic condition. The amount of PHB change in anaerobic stage was proportional to the P release capacity. The FISH detection showed that the more proportion of PAOs to the whole cell the more P removal ability in the system.

Abstract: With the frequent appearance of haze weather, haze-preventing has become one of the serious environmental problems. Among all measures, preventing inhalable particulate matter from the source is one of the most effective ways to eliminate haze. Based on the traditional water mist dust suppression technology, this paper developed a water-saving integrated system, by exploiting PROFIBUS-DP to connect water mist dust suppression system to gantry crane in port. This integrated system was demonstrated accurately spraying water mist while the crane dropping down coal. In this way, the suspended particulate matter is successfully inhibited, while fresh water is saved.