Abstract: Disclosed is a process for treating waste water through the use of activated carbon. The carbon is generally added to waste water having a pH from about 4 to about 11, and is commonly added after the waste water has undergone primary treatment. Preferred modes of operation comprise using low concentrations of activated carbon having a high surface area and a zeta potential greater than about -10 millivolts. It is also preferred to use activated carbon in conjunction with an activated sludge process having an average sludge age greater than about ten days, especially where the waste water undergoes a pretreatment prior to the activated sludge process to reduce chemical oxygen demand, oil and solids content. Low concentrations of activated carbon based on feed waste water are generally used while maintaining substantially higher carbon concentrations in the process.

Abstract: Disclosed is a process for the treatment of water so as to produce water of high purity, such as potable water. The process also entails the treatment of water which may have received prior water treatment, and comprises adding an effective amount of chemical flocculant to the feed water and subjecting said water to flocculation; passing the flocculated water to a clarifier where suspended solids are separated from the partially purified water; adding about 1 to about 100 parts powdered activated carbon per million parts of water from the clarifier; contacting the water with said carbon in a reaction zone so as to achieve substantial reduction of contaminants in the water; separating the activated carbon from the purified water; and recycling a portion of the separated activated carbon to the clarifier effluent.

Abstract: Disclosed is a waste water process for the treatment of strong wastes.

Abstract: Disclosed is an improved process for the treatment and purification of waste water. Generally the process comprises the use of primary, intermediate, and secondary treatment but tertiary treatment may also be included. Powdered activated carbon is used in the secondary treatment with recycle to any or all of the primary, intermediate or secondary treatment stages. Regeneration of used powdered activated carbon is also provided.

Abstract: Disclosed is a continuous process for purifying contaminated waste water. First the water passes through an equalization zone including at least two separate compartments, in one of which the pH of the water is adjusted to a range of from about 6.5 to 9.5. The water flows through the separate compartments such that the concentration of contaminants in the water exiting the equalization zone will approach about constant concentration which changes only gradually even though influent contaminant concentration changes rapidly. Water in at least one compartment of the equalization zone is aerated so that the dissolved oxygen in the water is at least three parts of dissolved oxygen per million parts of water. Solids are skimmed from the surface of the water in the zone, and coagulant is added to the effluent water from the equalization zone so that colloidal particles in the water flocculate. The water from this equalization zone is then filtered to remove flocculated particles.