Papers by Keyword: Removal

Abstract: Removal of SO₂ and NO from the flue gas using an aqueous sodium chlorite solution was achieved in a bubbling reactor, ORP and pH were used as monitoring parameter. The effect of pH, NaClO₂ feeding rate and SO₂ concentration on simultaneous removal of SO₂ and NO_x efficiencies were systematical investigated. The results showed that SO₂ removal efficiency was always 100% and NO_x removal efficiency could achieve 65% at optimized conditions, the optimized pH value of 5-5.5 was observed. The correlation analysis among ORP, original pH, NaClO₂ feeding rate and input SO₂ concentration was established using multiple regression equations.

Abstract: The adhesion of microorganisms to the floating cages in the aquaculture industry is currently controlled with copper as a biocide paints problem. The development of these activities has resulted in marine and freshwater sediments next to the culture centers high levels of copper. Due to these problems of environmental pollution, at present have been implemented new technologies of biological origin for the detoxification of ecosystems through the use of microorganisms (fungi, yeasts and bacteria). Therefore the main objective of this work is the search for marine microorganisms for the removal of copper. For this, samples were collected from marine sediment contaminated with copper Tenglo Channel (41 ° 29'23 .59 " S, 72 ° 58'06 .70" W). Gram negative bacterium of marine sediment was isolated in TSA medium supplemented with 7 mM Cu (II), this strain was designated as LMAE-2. The phylogenetic analysis has a 97 % similarity with Pantoea agglomerans. The high resistance for copper was determined at 9 mM. Finally, the metal removal capacity of this bacterium was determinate in 11.6% by Atomic Absorption Spectrometry. These results suggest that marine bacteria could be a biologic model system for use in processes for removal this toxic metal.

Abstract: The cadmium removed from sediment by rhamnolipid biosurfactant was explored in laboratory scale. The results suggest that the biosurfactant can remove cadmium from the sediment efficiently, 40% more than SDS. 200 mg/L rhamnolipid biosurfactant can get 84.02% cadmium removal efficiency from the sediment which contained 0.42 mg/g cadmium. pH affect cadmium removal by rhamnolipid, the best pH was 10. Leaching could also affect cadmium removal, there was a remarkable increasing of cadmium removal efficiency after the second washing, and after 48 h leaching cadmium removal and cadmium absorption got the balance.

Abstract: Diesel engine emissions of nitrogen oxides and particulates are the major source of air pollution that is a serious threat to human health. Diesel emissions treatment technology meet the increasingly stringent emission standards through the current difficulty and develop a new diesel engine exhausted treatment technology to further reduce the nitrogen oxide and particulate emissions are from diesel engines. In this paper, La_1-xA_xCo_1-yB_yO₃ complex perovskite catalysts for diesel engine exhaust emission purification carry out the relevant research, this article firstly study the perovskite oxide catalyst preparation methods, as the catalyst preparation process are described .Then the activity of the catalyst samples obtain some useful results.

Abstract: Hair dyeing wastewater is produced in coloring process. Its composition is complicated,in which contains a large number of organic pollutants and high color. Hair dyeing wastewater treatment can be effectively treated by Fenton oxidation method. The experiment results show that hair dyeing wastewater is treated by Fenton oxidation in this thesis. Fenton reagent is affected by hair dyeing wastewater, pH reaction time and many other factors. When raw water COD is 3800mg/L and chroma is 1210 times, by using Fenton oxidation method determine best experimental conditions: concentration of H2O2 is 24.5ml（30%H2O2), pH value is 3.0, nH2O2/nFe2+ is 7, reaction time is 60 min. Under the reaction condition , experimental results show that COD and color removal rates were 91.2% and 93.2% in hair dyeing wastewater by Fenton oxidation.

Abstract: To develop the proper filler for improving removal efficiency of ammonia nitrogen in the activated sludge process of wastewater treatment, the effects of the filler properties and treatment conditions on removal efficiency of ammonia nitrogen in hybrid biofilm-activated sludge process were investigated by the lab-scale test and pilot-scale test. Moreover, the feasibility of simultaneous nitrification and denitrification (SND) was explored with biofilm treatment for chemical poor-biological wastewater. The results showed that SND occurred in the aerobic section. The effluent total basicity (TB) in biofilm process was more than 2mmol / L, higher than activated sludge process. Correspondingly, the effluent TB in activated sludge process was about 0.1mmol / L, and nitrate produced by activated sludge process was 30 mg/L higher than biofilm process. Under the condition of HRT of 24 h for hydrolysis-acidification tank, HRT of 4 h for anoxic tank and HRT of 16 h for aerobic tank, effluent NOˉx-N with combination type of filler in biofilm process was 20mg/L less than that with the activated sludge process. TB with combination type of filler in biofilm process was 2mmol/L less than that with the activated sludge process. Nitrogen removal efficiency was 10.46% with SJ-1 type of filler (made in Jiangsu Suzhou Purification Group Co.,Ltd) more than with combination type of filler. The effluent NOˉx-N concentrations was less than.15mg/L in biofilm process with SJ-1 type of filler. A practical mathematical model with the A/O process was developed for predicting removal effects, which can provide a theoretical guidance for wastewater treatment and engineering design.

Abstract: Two aquatic macrophytes (Lythrum salicaria and Alisma plantago-aquatica) were grown in monoculture to test the relative growth rate (RGR) and abilities of removing total phosphorus (TP) by the manipulative indoor experiment. A nutrient treatment consisted of two levels of phosphorus [ low (3 mg L^-1 N) and high (12 mg L^-1 N) ] of nutrient solution. Result revealed that nutrients had significant affect on the RGR, however the RGR of the species was non-significant. The results showed that TP in wastewater were significantly higher from unvegetated microcosms compared to vegetated. L. salicaria was shown to be best removal effect with the removal rates of 81.7% and 91.1% at low and high concentrations of TP.

Abstract: Indigo carmine (IC) is one of the oldest, most important and highly toxic dyes used and released in the effluents of many industries, such as textile, paper and plastics. Biogenic Mn oxides (BMO) were prepared by culturing Marinobacter sp. MnI7-9 in presence of Mn (II). The Point of Zero Charge (PZC) of the BMO is 7.5 by salt titration method. The surface area (BET) is 27.68 m² g^-1 by the nitrogen adsorption-desorption method. The adsorption kinetics of low concentration IC (5 mg L^-1) on the BMO fit the pseudo-first order model, while the adsorption kinetics of higher concentration IC (20 mg L^-1) fit the pseudo-second order model. Intra-particle diffusion is an important rate-controlling step. The equilibrium adsorption data fit well in the Langmuir isotherm equation. The maximal adsorption capacity is 115.61 mg g^-1 at 25¡æ. A larger IC removal amount can be obtained when the amount of the BMO is 2 g L^-1 at pH 6.5. These results suggest that the BMO can be used as an efficient material for IC removal from aqueous solution.

Abstract: Movie shooting caused large quantities of oil emissions into the surrounding frequently , the water quality could be contanminate. EPDM rubber was chosen as the main matrix to prepare foam oil absorption material by simple melt blending and molded foaming. The impact of DCP and AC on oil-absorbing properties of materials was studied, and the optimal amount of DCP and AC was 1.5Phr and 10Phr; Through foaming process, the oil absorbency was greatly improved, and the maximum oil absorbency was 12.73g/g which was increased by 566.5% compared to the corresponding solid material. This composite is an inexpensive, convenient and high efficiency material for removing oils from movie shooting.

Abstract: With the development of urbanization, the odor from municipal wastewater treatment plants has disturbed the neighborhood and the control of odor has become an urgency research subject. The H₂S odor was treated by the biofilter. The removal load of the biofilter, end products of H₂S degradation, and operation process were studied in this paper. The results of removal H₂S odor with the biofilter were as follows: When the gas flow rate was 1000m³/h (resident time 16.2s) and 1250m³/h (resident time 13.0s), and the inlet concentration of H₂S ranged from 1.876 to 34.705mg/m³, the removal rate maintained above 99.92%, and the average outlet concentration was 0.001 mg/m³ which was far lower than the national level of discharge standard. The relationship between removal rate and temperature satisfied with the formula , and for H₂S, θ=1.016. Furthermore, the end products of H₂S degradation were only sulfate without sulfide. With the increase of sulfate, the removal of H₂S was not affected. The study of operating parameters with the biofilter provided the necessary technical support for industrial design and operation control.