RESUMEN
Oily sludge contains high concentrations of total petroleum hydrocarbons and heavy metals, which seriously impact the environment and human health. How to dispose of and use the oily sludge has attracted an increasing amount of attention. This study introduces harmless and resource-based oily sludge treatment technologies. It summarizes the technologies from various aspects, such as the process principle, influencing factors, advantages, and disadvantages, and analyzes and summarizes the status quo of the development of the technologies. In comparison, the direction of processing technology development is discussed to provide reference for processing technology improvements, optimization, and efficiency improvements.
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Metales Pesados , Petróleo , Humanos , Hidrocarburos , Aceites , Petróleo/análisis , Aguas del AlcantarilladoRESUMEN
Sequential vertical flow trickling filter and horizontal flow multi-soil-layering bioreactor were investigated for the treatment of decentralized domestic wastewater at various concentrations of sodium dodecyl benzene sulfonate (SDBS). Results have shown that the removal rate of COD could reach 92.1% at initial COD concentration of 960 mg/L (800 mg/L was provided by SDBS). NH4+-N concentration could be reduced from 52.4 to 9.71 mg/L without aeration. Besides, a quadratic function model was fit to describe the relationship between the relative activity of amylase and the protein content in extracellular polymer substance. SDBS could inhibit the transport and metabolisms of amino acids, lipids and carbohydrates in biofilms. The analysis of three-dimensional fluorescence diagram indicated that the peak in excitation/emission wavelengths = 310-340/370-430 nm was the characteristic peaks of some active substances such as some enzymes in EPS. Only Microbacterium could totally offset the toxicity of SDBS degradation products.
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Suelo , Aguas Residuales , Bencenosulfonatos , Reactores BiológicosRESUMEN
In this study, the effect of various supports on activation of peroxymonosulfate and consequent degradation of Acid Orange 7 (AO7) in aqueous solutions was examined at the presence of LaFeO3 perovskite as catalyst. Results showed that the AO7 degradation efficiency by LaFeO3 supported on different supports was in an order of LaFeO3/Al2O3 (86.2%)â¯>â¯LaFeO3 (70.8%)â¯>â¯LaFeO3/CeO2 (59.0%)â¯>â¯LaFeO3/SiO2 (52.3%)â¯>â¯LaFeO3/TiO2 (32.2%). Moreover, the pseudo first-order rate constant for AO7 degradation by LaFeO3/Al2O3 was 3.2 times than that by LaFeO3. The enhancement was attributed to its large surface area, abundant chemisorbed surface-active oxygen, redox property and faster electron transfer. AO7 degradation and the leaching of iron ions decreased with the increase of pH. Data of electron spin resonance spectroscopy and quenching experiments revealed that sulfate and hydroxyl radicals were generated on LaFeO3/Al2O3 surface, while sulfate radicals were identified to be the main reactive species responsible for AO7 degradation. Mechanisms for peroxymonosulfate activation were consequently proposed. Furthermore, LaFeO3/Al2O3 catalyst exhibited a superior stability after five cycles. This work provides a new approach for design of iron-based perovskite catalysts with high and stable catalytic activity for removal of organic pollutants from aqueous solutions.
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Compuestos de Calcio/química , Contaminantes Ambientales/química , Óxidos/química , Titanio/química , Óxido de Aluminio/química , Compuestos Azo , Bencenosulfonatos , Catálisis , Radical Hidroxilo , Hierro , Modelos Químicos , Oxidación-Reducción , Peróxidos , Dióxido de Silicio , SulfatosRESUMEN
OBJECTIVE: To observe the validity and safety of Kangxin capsule curing the patients with vascular dementia (VaD). PATIENTS AND METHODS: Fifty-six patients with vascular dementia of kidney deficiency and blood stagnation type were selected on the basis of defined diagnostic criteria and were randomly divided into Kangxin group (29) and control group (27), observing the relevant accumulation scores in dementia scale before and after treatment and changes of endothelin (ET), sex hormone, immunity and routine examinations. RESULTS: Kangxin capsule can effectively improve the symptom of patients with VaD of senile kidney deficiency and blood stagnation type, and the average value of curative effect index of 29 patients in the treatment group is 23.01>/=20%, i.e. effective; compared with that before treatment, both CD(4) and CD(4).CD(8)(-1) rises (P<0.05) after the treatment with Kangxin capsule; for the male VaD patients of the Kangxin group, T level increases (P<0.05) and estrodial (E(2)).testerone (T)(-1) value decreases (P<0.05) after the treatment; for the female VaD patients of the Kangxin group, E(2), E(2).T(-1) value increases a great deal (P<0.05) compared with that before treatment; ET level of both groups decreased on average (P<0.01), and did not demonstrate any obvious toxic side effect. CONCLUSIONS: Kangxin capsule is a valid and safe preparation of Chinese traditional medicine for curing VaD of senile kidney deficiency and blood stagnation type.