Considerations on Applying Practical Control Methods in the Biological Treatment of Wastewaters from Paper Manufacturing

Due to high efficiency, in terms of effluent quality, the activated sludge treatment is the most common method for removing the biodegradable impurities from industrial and urban wastewaters. Although these engineering systems of biological wastewater treatments increase the rate of biodegradable substances removing, in most cases, these are rarely able to achieve the maximum performances due to the lack of some fast methods to monitor and control the living biomass. In this context, in present paper are described some methods for evaluation of viability and biological activity of activated sludge, as essential parameters for ensuring the performance of biological treatment process. The proposed methods are based on the determination of metabolically active bacteria in activated sludge, using the activity of dehydrogenase enzymes (Triphenyl tetrazolium chloride TTC method) in the biological treatment of wastewaters generated from the paper manufacturing process

Physico-Chemical Water Treated with Sonic Generator and Al2(SO4)3 Coagulant

This paper is a study on the problem of using ultrasound in the treatment of raw water. It highlights the effect of ultrasounds produced by the experimental sonic ultrasound generator through the physico-chemical analysis of raw water, as well as of the treated water, namely turbidity, pH and dissolved oxygen. Also, to reduce the dose of coagulant used in water treatment plants, we studied the influence of ultrasound on water treated with coagulant based on the physicochemical parameters analysis. The aim of this paper was to determine the effects of ultrasound and of the coagulant on the physico-chemical parameters of water by treating raw water with ultrasonic gas-dynamic generators, or by adding coagulant, with reference to water quality before treatment. We followed the environmental impact by allowing the use of the sonic generator technology treatment leading to significant reduction in the amount of chemicals commonly used in water treatment stations in view of clotting suspension

Study on the Sludge Capitalization as a Fertilizer for Ornamental Garden Plants

The paper aimed to demonstrate that the sludge from wastewater treatment plants can be used efficiently as a fertilizer in horticulture because in the near future the storage of this sludge will become a problem. For this reason, we approached the study on the recovery of the sludge from the wastewater treatment plant of Brăila as fertilizer in the crops of ornamental garden plants that are not intended for consumption. The correct management of the sludge from wastewater treatment plants may bring a positive contribution to the vegetation development rate. The main objective of the sludge treatment is the capitalization and the decrease of negative impact on the environment