Experiment study on the treatment effect of the hydrocarbon degradation microorganism to treat the oily wastewater

Adopts the method of adding demulsifiers into the oily wastewater to increase the droplets size to further improve the efficiency of oil-water separation, and puts forward the corresponding optimized indicators and methods of demulsifiers. The optimized selection of the demulsifiers and its additive dosage was carried out by indoor experiments based on the optimized indicators. Using artificial produced water to test the treatment effect of the optimized demulsifier at different action time. The experiments show that demulsifier S1 with additive dosage of 20mg/l can accordance with the requirements of the processing very well, and as the increase of action time, the average size of droplets increase and the amount of the droplets which under 1μm decrease.

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Experiment Study on Treatment of Chromium(VI)-Containing Groundwater by Modified Synthetic Zeolite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.1253 ◽

2012 ◽

Vol 430-432 ◽

pp. 1253-1256 ◽

Cited By ~ 1

Author(s):

Yu Jie Huang ◽

Huan Zhen Zhang

Keyword(s):

Adsorption Isotherm ◽

Hexavalent Chromium ◽

Treatment Effect ◽

Synthetic Zeolite ◽

Experiment Study ◽

Ph Adjustment ◽

Modified Zeolite ◽

Solid Ratio ◽

Chromium Vi ◽

Freundlich Adsorption Isotherm

In order to improve the removal ability of hexavalent chromium on the synthetic zeolite, the synthetic zeolite was modified by FeSO4, which was used to removal hexavalent chromium in groundwater. The results showed that the concentration of Cr (VI) can be reduced from 5.0mg/l to 0.03 mg/l, which meets the requirements of groundwater standards (0.05mg/l) by using modified zeolite in a liquid-to-solid ratio of 20 ml/g, pH=3 for 120 minutes. The adsorption of Cr (VI) on the modified synthetic zeolite could be described by the Langmuir and Freundlich adsorption isotherm. It is showed that the synthetic zeolite modified by FeSO4 has good treatment effect and after treatment the pH of groundwater can reach around 6.8, which need no more pH adjustment.

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Formation and performance of Kaolin/MnO2 bi-layer composite dynamic membrane for oily wastewater treatment: Effect of solution conditions

Desalination ◽

10.1016/j.desal.2010.11.019 ◽

2011 ◽

Vol 270 (1-3) ◽

pp. 50-56 ◽

Cited By ~ 49

Author(s):

Tao Yang ◽

Zheng-Fei Ma ◽

Qi-Yong Yang

Keyword(s):

Wastewater Treatment ◽

Treatment Effect ◽

Oily Wastewater ◽

Dynamic Membrane ◽

Layer Composite ◽

And Performance ◽

Oily Wastewater Treatment

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Comparison of Several Technical Treatment of Oily Wastewater by Fly Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.2747 ◽

2014 ◽

Vol 955-959 ◽

pp. 2747-2750 ◽

Cited By ~ 1

Author(s):

Tao Yin ◽

Xiang Yang Huang

Keyword(s):

Reaction Mechanism ◽

Fly Ash ◽

Adsorption Capacity ◽

Treatment Effect ◽

Future Research ◽

Oily Wastewater ◽

Oil Removal ◽

Dual Effect ◽

Treatment Processes ◽

Final Treatment

Oily wastewater and fly ash will cause great pollution to the environment, the paper reviewed the fly ash as the oil removal medium, through the means of directly adding as adsorbents, preparing fly ash ceramisite, adding to remove oil after modification and combing with other treatment processes, etc., had better treatment effect on a variety of oily wastewater generated from different backgrounds. The results showed that using fly ash to treat the oily wastewater could achieve "using waste to treat waste", and could play a dual effect on the environmental protection. Meanwhile it pointed out deficiencies in the existing processes, and the future research should rely mainly on improving the adsorption capacity, the separation and the final treatment of saturated fly ash, and strengthening the research on reaction mechanism.

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The Effect of Partly Missing Covariates on Statistical Power in Randomized Controlled Trials With Discrete-Time Survival Endpoints

Methodology ◽

10.1027/1614-2241/a000121 ◽

2017 ◽

Vol 13 (2) ◽

pp. 41-60

Author(s):

Shahab Jolani ◽

Maryam Safarkhani

Keyword(s):

Randomized Controlled Trials ◽

Discrete Time ◽

Treatment Effect ◽

Survival Data ◽

Controlled Trials ◽

Missing Covariates ◽

Indicator Method ◽

Imputation Methods ◽

Randomized Controlled ◽

Baseline Covariates

Abstract. In randomized controlled trials (RCTs), a common strategy to increase power to detect a treatment effect is adjustment for baseline covariates. However, adjustment with partly missing covariates, where complete cases are only used, is inefficient. We consider different alternatives in trials with discrete-time survival data, where subjects are measured in discrete-time intervals while they may experience an event at any point in time. The results of a Monte Carlo simulation study, as well as a case study of randomized trials in smokers with attention deficit hyperactivity disorder (ADHD), indicated that single and multiple imputation methods outperform the other methods and increase precision in estimating the treatment effect. Missing indicator method, which uses a dummy variable in the statistical model to indicate whether the value for that variable is missing and sets the same value to all missing values, is comparable to imputation methods. Nevertheless, the power level to detect the treatment effect based on missing indicator method is marginally lower than the imputation methods, particularly when the missingness depends on the outcome. In conclusion, it appears that imputation of partly missing (baseline) covariates should be preferred in the analysis of discrete-time survival data.

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