scholarly journals Cleaner Production Assessment of Fast Bordeaux GP Base

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Mausumi Mukhopadhyay ◽  
Rashmita D. Patel
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Chemical Oxygen Demand ◽  
Pilot Plant ◽  
Oxygen Demand ◽  
Feasibility Studies ◽  
Cleaner Production ◽  
Raw Material ◽  
Molar Ratio ◽  
High Chemical Oxygen Demand

The pilot plant study of cleaner production (CP) process of a dyes intermediate, Fast Bordeaux GP Base (2-nitro-p-anisidine), is presented in this work. The existing production process with acetic anhydride as raw material generates highly polluting (high chemical oxygen demand), huge-volume effluent, and thus the treatment is expensive. In the proposed process, raw material acetic anhydride in acetylation step is replaced with acetic acid. The reaction conditions like reaction time (3 h), temperature (120∘C) and molar ratio of p-anisidine and acetic acid (1 : 3.58) are optimized in the laboratory scale and implemented in pilot plant. The extent of conversion has been monitored by nitrite value test, and purity of product mixture is measured with thin-layer chromatography (TLC). The acidic wastewater quantity is dramatically reduced by incorporating recycling in washing scheme, and thus water consumption is reduced. Reduction in wastewater generation and reduction/elimination of treatment cost is also observed. Chemical oxygen demand (COD) of the effluent stream is reduced by the recovery of by-products sodium acetate and spent acid. The technoeconomical feasibility studies show that the proposed CP options are highly economical and environmental friendly.

scholarly journals Red Mud-Based Polyaluminum Ferric Chloride Flocculant: Preparation, Characterization and Flocculation Performance

2021 ◽  
Author(s):  
Yong Cheng ◽  
Longjun Xu ◽  
Chenglun Liu ◽  
Zao Jiang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Red Mud ◽  
High Efficiency ◽  
Low Cost ◽  
Oxygen Demand ◽  
Industrial Applications ◽  
Iron Chloride ◽  
Raw Material ◽  
Molar Ratio ◽  
Polymerization Temperature ◽  
Solution Ph

Abstract In this work, red mud was used as raw material to extract Al and Fe with hydrochloric acid. The high-efficiency polyaluminum iron chloride (PAFC) flocculant was prepared via adjusting the pH of the leaching solution, the molar ratio of aluminum and iron, and the polymerization temperature. The effect of synthesis and flocculation conditions on the flocculation performance of aged landfill leachate was investigated. The results confirmed that the PAFC prepared at the polymerization pH of 2.5, the Al/Fe molar ratio of 8, and the polymerization temperature of 70 °C had the optimum flocculation effect. The flocculation consequences of PAFC and commercial polyaluminum iron chloride flocculant (CPAFC) under different flocculation conditions were compared. The chemical oxygen demand (COD), UV254, chroma and settlement height of PAFC at flocculant concentration of 60 g/L and solution pH of 6 were 72.2%, 79.2%, 82.9% and 9.5 cm (within 90 min), respectively. PAFC has excellent flocculation performance and can be used as a simple, potentially low-cost wastewater treatment agent in industrial applications.

scholarly journals Synthesis of Nd-doped ZSM-5 and its application to treating slightly polluted water

2017 ◽  
Vol 8 (1) ◽  
pp. 86-93
Author(s):  
Mang Lu ◽  
Lin He ◽  
Yue Cheng
Keyword(s):  
Contact Time ◽  
Oxygen Demand ◽  
Raw Material ◽  
Molar Ratio ◽  
Polluted Water ◽  
Solution Ph ◽  
Experimental Conditions ◽  
Factors Influencing ◽  
Orthogonal Experiments ◽  
Removal Efficiencies

Abstract In this study, ZSM-5 zeolite was synthesized using diatomaceous mud as the raw material, and then doped with different amounts of Nd2O3. The orthogonal experiments were performed to investigate the influence of Nd:Si molar ratio, zeolite dosage, contact time, solution pH and temperature on the removal of humic acid (HA). The removal of HA was comprehensively evaluated by chemical oxygen demand (COD), UV254 and UV410 of the solution. The results demonstrate that solution pH and zeolite dosage are the two most important factors influencing HA adsorption. The optimum experimental conditions were determined to be: 35 °C, Nd:Si molar ratio of 1:100, 2.0 g/L zeolite, pH 4 and 50 min contact time. Under these conditions, the removal efficiencies of UV254, UV410 and COD are 82.70%, 76.00% and 82.10%, respectively, corresponding to a comprehensive removal of 81.02%.

Edible Plant Oil Wastewater Treatment Using Electro-Fenton Technique: Experiment and Correlation

2018 ◽  
Vol 16 (8) ◽  
Author(s):  
Reza Davarnejad ◽  
Seyed Amir Mohajerani
Keyword(s):  
Reaction Time ◽  
Current Density ◽  
Oxygen Demand ◽  
Volume Ratio ◽  
Cod Removal ◽  
Interactive Effects ◽  
Molar Ratio ◽  
Plant Oil ◽  
Edible Plant ◽  
High Chemical Oxygen Demand

Abstract The edible plant oil production factories consume high amounts of water and contaminate the water resources. This type of wastewater consists of high chemical oxygen demand (COD) which should properly be treated by an efficient technique. Furthermore, it is containing some chemicals obtained from several sources such as H3PO4 (from hydration section), NaOH (from neutralization section) and citric acid (from nickel removal section). The conventional techniques cannot efficiently treat it which is full of COD. Therefore, the electro-Fenton process as a rapid, compact and efficient one has been encouraged to be applied. For this purpose, 47 experiments were designed and carried out using iron electrodes to evaluate the effects of five significant independent variables such as reaction time (min), pH, current density (mA/cm2), volume ratio of H2O2/wastewater (ml/l) and H2O2/Fe2+ molar ratio on the COD removal. Response surface methodology (RSM) was employed to assess individual and interactive effects of the parameters. The optimum conditions were experimentally obtained at reaction time of 87.33 min, pH of 3.03, current density of 57 mA/cm2, H2O2/wastewater volume ratio of 2.13 ml/l and H2O2/Fe2+ molar ratio of 3.61 for COD removal of 62.94 %.

scholarly journals Simulating the impact of piers on hydrodynamics and pollutant transport: A case study in the Middle Yangtze River

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260527
Author(s):  
Haibin Xiong ◽  
Li Chen ◽  
Zhaohua Sun ◽  
Zhiqing Li ◽  
Kun Zhou ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Oxygen Demand ◽  
Cumulative Effect ◽  
Critical Value ◽  
Temporal Variations ◽  
Hydrodynamic Characteristics ◽  
High Chemical ◽  
High Chemical Oxygen Demand ◽  
The Impact ◽  
Chemical Oxygen Demand Concentration

It is known that channel engineering, including the construction of piers, will change the river hydrodynamic characteristics, which is a significant factor affecting the transport process of pollutants. With this regard, this study uses the well-validated and tested hydrodynamic module and transport module of MIKE 21 to simulate the hydrodynamics and water quality under various pier densities in the Wuhan reach. Hydrodynamic changes around the piers show spatial differences, which are similar under different discharges. The range and amplitude of hydrodynamic spatial variations increase with the increase in pier density. However, there is a critical value of 1.25 to 2.5 units/km. When the pier density is less than this critical value, this type of cumulative effect is the most significant. Additionally, greater changes can be found in chemical oxygen demand concentrations, which also show spatial and temporal variations. The area with high chemical oxygen demand concentration upstream and downstream from the engineering area exhibits the distribution characteristics of “decrease in the downstream area and increase in the upstream area” and “increase in downstream the area and decrease in the upstream area” respectively. In the reach section of the engineering area, the area with high chemical oxygen demand concentration increases in the front area near the piers and decreases near the shoreline. Furthermore, the concentration shows attenuation actions with a longer residence time owing to the buffering effect of pier groups. These results have significant implications on shoreline planning and utilization. Moreover, they provide scientific guidelines for water management.

scholarly journals COD reduction of process wastewater with vacuum evaporation

2018 ◽  
Vol 3 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Andras Jozsef Toth ◽  
Eniko Haaz ◽  
Botond Szilagyi ◽  
Tibor Nagy ◽  
Ariella Janka Tarjani ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Heat Pump ◽  
Chemical Industry ◽  
Circular Economy ◽  
Environmental Problem ◽  
Oxygen Demand ◽  
High Chemical ◽  
Problem Method ◽  
Process Wastewater ◽  
High Chemical Oxygen Demand

Abstract Washing detergents in process wastewaters from fine chemical industry produce high Chemical Oxygen Demand (COD), which poses a serious environmental problem. Method has to be found, which follows the principles of circular economy so that the treated water can be recycled or reused. Heat pump vacuum evaporator is evaluated in order to reduce the Chemical Oxygen Demand of process wastewater with washing detergent content from initial 7500 mg O2/L to a lower value below the effluent limit , which is 1000 mg O2/L. Yield and COD rejection are determined for the evaluation of selected treatment. Experiments are investigated with LED Italia R150-v3 pilot apparatus. Different evaporation pressures were applied during measurements. It The highest removal or reduction of in the Chemical Oxygen Demand was reached certainly using the lowest possible pressure, which is 40 mbar.

scholarly journals Green Ferrate(VI) for Multiple Treatments of Fracturing Wastewater: Demulsification, Visbreaking, and Chemical Oxygen Demand Removal

2019 ◽  
Vol 20 (8) ◽  
pp. 1857 ◽  
Author(s):  
Hongjing Han ◽  
Jinxin Li ◽  
Qin Ge ◽  
Yizhen Wang ◽  
Yanguang Chen ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Promising Result ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Efficient Treatment ◽  
Mechanistic Analysis ◽  
Ft Ir ◽  
Multiple Treatments ◽  
High Chemical Oxygen Demand

Fracturing wastewater is often highly emulsified, viscous, and has a high chemical oxygen demand (COD), which makes it difficult to treat and recycle. Ferrate(VI) is a green oxidant that has a high redox potential and has been adopted for the efficient oxidation of fracturing wastewater to achieve triple effects: demulsification, visbreaking, and COD removal. Firstly, optimal conditions were identified to build a model for fast and efficient treatment. Secondly, wastewater treatment using ferrate oxidation was investigated via demulsification, visbreaking, and COD removal. Finally, a mechanism for ferrate oxidation was proposed for the three effects using Fourier-transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The theoretical and experimental data demonstrated that the ferrate oxidation achieved the three desired effects. When ferrate was added, the demulsification efficiency increased from 56.2% to 91.8%, the total viscosity dropped from 1.45 cp to 1.10 cp, and the total removal rate of COD significantly increased to 74.2%. A mechanistic analysis showed that the strongly-oxidizing ferrate easily and efficiently oxidized the O/W interfacial film materials, viscous polymers, and compounds responsible for the COD, which was a promising result for the triple effects.

Chlorella vulgaris biomass production using brewery wastewater with high chemical oxygen demand

2020 ◽  
Vol 32 (5) ◽  
pp. 2773-2783
Author(s):  
Julieta Lois-Milevicich ◽  
Nahuel Casá ◽  
Paola Alvarez ◽  
Ricardo Mateucci ◽  
Víctor Busto ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Biomass Production ◽  
Chlorella Vulgaris ◽  
Oxygen Demand ◽  
Brewery Wastewater ◽  
High Chemical ◽  
High Chemical Oxygen Demand
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