Sharif Digital Repository

A critical property in designing drilling fluids is the concerns for environmental damages and cost efficiency of mud additives used to complete a well safely and economically. Designing drilling fluids for harsh environments such as high temperature, high salinity formation water, lime and cement contamination demands proper selection of deflocculant (thinner) materials to achieve a successful drilling operation. This study presents a novel thinner material that satisfies the goal of an environmentally and economically acceptable mud in drilling lime contamination areas where drilling carbonate formations with high concentration of calcium ions tends to flocculate clay particles in... 

In this project, Olive Mill Wastes (OMW) has been considered as a raw material for a bio-refinery. The project is consisted of a design section using SuperPro Designer software and an experimental section. The biorefinery was designed using the software after conducting a survey on the production of different value added material from OMW. The designed process consisted of xanthan gum, methane gas and agriculture fertilizer production. As much as 15000 L of the diluted OMW (to 50% of the initial concentration) is purified and 88 Kg xanthan gum (in 7 days), 2840 Kg methane gas and 200 Kg fertilizer in 25 days are produced at the same time.
In the experimental section, effect of applying... 

Membrane bioreactor (MBR) is a combination of conventional activated sludge (CAS) and membrane filtration which owing to its advantages such as high quality effluent and low excess sludge production, has gained increasing application in wastewater treatment. The major drawback of a MBR is the membrane fouling that reduces the permeate flux, which in turn increases the overall operational costs due to high energy requirements. In existing study, the combination of sludge oxidation and coagulation/flocculation addition was investigated for mitigation of membrane fouling in a membrane bioreactor. Oxidation can facilitate sludge flocculation and hence improve the properties of mixed liquor. The... 

Microalgae is a major problem in water resources due to its adverse influence on water treatment process and water quality like color, odor and taste. In addition microalgae removal is an important process in food and pharmacy industry. Electrocoagulation is a potential method for microalgae removal. Another method for microalgae recovery is membrane treatment. This study is focusing on using both methods separately and simultaneously. To achieve this, the removal of Chlorella Vulgaris, a fresh water microalgae, was used in experiments. In first phase the experiments were solely on electrocoagulation and the effect of several parameters including current density, electrocoagulation duration,... 

Golpayegan Qaed Basir Petrochemical Company is one of the lucrative and entrepreneurial companies in Iran. Every day in this complex, a large amount of wastewater is being generated and transferred to the evaporative lag after the primary and secondary purification outside the complex and it is not restored. Considering the growing importance of surface and underground water resources, reuse of wastewater is a valuable production. In this research, the optimization of the sewage treatment system of the complex was evaluated by replacing the chemicals in the primary purification unit and also by using chloride-ferric and trickling filter for tertiary purification(treating) of the... 

Paper and cardboard waste pulping consume large volumes of water, so the discharge of this effluent without proper treatment can have far-reaching environmental consequences. The color and variable COD concentration of wastewater in this industry make treating this wastewater complicated. Therefore, this study aims to reduce the COD of the wastewater treatment plant of a pulp and paper mill under different laboratory conditions to achieve environmental standards in Iran.In this study, coagulation-flocculation and the Fenton process on the wastewater entering the treatment plant were investigated first. It was found that coagulation and flocculation by 750-1250 ppm of alum coagulant and ten...