Dispersible wastes Highly dispersed or mixed with other wastes: Waste water Hard-To-Treat Wastes Resist treatment Contain non biodegradable or inorganic Cannot be removed by biological processes High- Volume Wastes High-volume wastes in textiles include wash water, alkaline wastes, warp sizes Hazardous or Toxic Wastes Subgroup of hard-to-treat wastes. Metals, chlorinated solvents, non degradable surfactants Dispersible wastes Highly dispersed or mixed with other wastes: Waste water Hard-To-Treat Wastes Resist treatment Contain non biodegradable or inorganic Cannot be removed by biological processes High- Volume Wastes High-volume wastes in textiles include wash water, alkaline wastes, warp sizes Hazardous or Toxic Wastes Subgroup of hard-to-treat wastes. Metals, chlorinated solvents, non degradable surfactants 6 General Waste Categorization [More]

Dispersible wastes Highly dispersed or mixed with other wastes: Waste water Hard-To-Treat Wastes Resist treatment Contain non biodegradable or inorganic Cannot be removed by biological processes High- Volume Wastes High-volume wastes in textiles include wash water, alkaline wastes, warp sizes Hazardous or Toxic Wastes Subgroup of hard-to-treat wastes. Metals, chlorinated solvents, non degradable surfactants Dispersible wastes Highly dispersed or mixed with other wastes: Waste water Hard-To-Treat Wastes Resist treatment Contain non biodegradable or inorganic Cannot be removed by biological processes High- Volume Wastes High-volume wastes in textiles include wash water, alkaline wastes, warp sizes Hazardous or Toxic Wastes Subgroup of hard-to-treat wastes. Metals, chlorinated solvents, non degradable surfactants 6 General Waste Categorization [More]

Primary Treatment After the removal of gross solids, gritty materials and excessive quantities of oil and grease, the next step is to remove the remaining suspended solids as much as possible. This step is aimed at reducing the strength of the waste water and also to facilitate secondary treatment. Screening: Coarse suspended matters such as rags, pieces of fabric, fibres, yarns and lint are removed. Bar screens and mechanically cleaned fine screens remove most of the fibres. The suspended fibres have to be removed prior to secondary biological treatment; otherwise they may affect the secondary treatment system. They are reported to clog trickling filters, seals or carbon beads. Sedimentation: The suspended matter in textile effluent can be removed efficiently and economically by sedimentation. This process is particularly useful for treatment of wastes containing high percentage of settable solids or when the waste is subjected to combined treatment with sewage. The sedimentation tanks are designed to enable smaller and lighter particles to settle under gravity. The most common equipment used includes horizontal flow sedimentation tanks and centre-feed circular clarifiers. The settled sludge is removed from the sedimentation tanks by mechanical scrapping into hoppers and pumping it out subsequently. Equalization: Effluent streams are collected into sump pit. Sometimes mixed effluents are stirred by rotating agitators or by blowing compressed air from below. The pit has a conical bottom for enhancing the settling of solid particles. [More]

Electrochemical oxidation is considered a robust technology and is easy to use, for those reasons, it has been used for a diversity of wastewater treatments. The main advantages of this technology over other conventional treatments are as follows: the main reagent is the electron; many processes occur in the electrochemical cell; the addition of chemicals is not required; and the process is carried out at room temperature and atmospheric pressure. Ozone is a powerful oxidant produced in gas phase, and by means of a diffuser, a mass transfer occurs to aqueous solution. A main advantage of ozone is that it oxidizes organic compounds without producing residual sludge. However, it was found that some compounds are ozone-resistant such as iopamidol, sucralose and atrazine-desethyl. [More]

Electrochemical oxidation is considered a robust technology and is easy to use, for those reasons, it has been used for a diversity of wastewater treatments. The main advantages of this technology over other conventional treatments are as follows: the main reagent is the electron; many processes occur in the electrochemical cell; the addition of chemicals is not required; and the process is carried out at room temperature and atmospheric pressure. Ozone is a powerful oxidant produced in gas phase, and by means of a diffuser, a mass transfer occurs to aqueous solution. A main advantage of ozone is that it oxidizes organic compounds without producing residual sludge. However, it was found that some compounds are ozone-resistant such as iopamidol, sucralose and atrazine-desethyl. [More]

Electrocoagulation consists of pairs of metal sheets called electrodes, that are arranged in pairs of twoanodes and cathodes. Using the principles water is reduced (gains electrons), thereby making the wastewater better treated. When the cathode electrode makes contact with the wastewater, the metal is emitted into the apparatus of electrochemistry, the cathode is oxidized (loses electrons), while the When this happens, the particulates are neutralized by the formation of hydroxide complexes for the purpose of forming agglomerates. These agglomerates begin to form at the bottom of the tank and can be siphen out through filtration. However, when one considers an electro coagulation-flotation apparatus, the particulates would instead float to the top of the tank by means of formed hydrogen bubbles that are created from the anode. The floated particulates can be skimmed from the top of the tank. [More]

Electrocoagulation-electroflotation (ECF) technology is a treatment process of applying electrical current to treat and flocculate contaminants without having to add coagulations. Shammas et al. stated that coagulation occurs with the current being applied, capable of removing small particles since direct current applied, setting them into motion. Also electrocoagulation could reduce residue for waste production [More]

When this happens, the particulates are neutralized by the formation of hydroxide complexes for the purpose of forming agglomerates. These agglomerates begin to form at the bottom of the tank and can be siphen out through filtration. However, when one considers an electro coagulation-flotation apparatus, the particulates would instead float to the top of the tank by means of formed hydrogen bubbles that are created from the anode. The floated particulates can be skimmed from the top of the tank. To consider how effective the ECF reactor can be, one must consider the following inputs or variableswastewater type, pH, current density, type of metal electrodes (aluminum, steel, iron), number of electrodes, size of electrodes, and configuration of metals. These variables would affect the overall treatment time, kinetics, and also the removal efficiency measured. [More]

Electro Coagulation Reactor (ECR) consists of electrodes, which is arranged in anode & cathode. Using the principles of electrochemistry, the cathode is oxidized (loses electrons), while the water is reduced (gains electrons), thereby making the wastewater better treated. [More]

Electrocoagulation-flotation is an alternative method to classic chemical coagulation for many reasons. ECF is capable of reducing the need for chemicals due to the fact that the electrodes provide the coagulant. However, many individuals still use chemical coagulants to attempt to enhance treatment. Traditionally, chemical coagulation involves the use of alum (aluminum sulfate), ferric chloride (FeCl3), or ferrous sulfate (Fe2SO4) which can be very expensive depending on the volume of water treated. When applying the coagulant, the coagulant performs a similar function as the electrodes, neutralizing the charge of the particulates, thereby allow them to agglomerate and settle at the bottom of the tank. In addition, electrocoagulation-flotation is capable of reducing waste production from wastewater treatment and also reduces the time necessary for treatment. [More]