Design and implementation of wastewater treatment projects

Summary

The analysis of technical solutions of surface run-off treatment process flow schemes is presented. The attention is focused on the necessity of selecting a treatment system in every specific case relying on the analysis of wastewater type and local drainage system. In addition the technological orientation of the local industries discharging their effluents into the municipal sewer shall be considered. One of the possible solutions of the given problem is the expediency of treatment of industrial effluents discharged into the storm sewer at the local treatment facilities located on the surface in a separate building or box at the industrial enterprise's premises.

Key words

settling , flotation , sorption , filtration , local treatment , retention basin-settler , underground treatment facilities

Substantiating the use of aluminium sulfate for the elimination of phosphorus from wastewater at the Saint-Petersburg wastewater treatment facilities

Summary

The article opens a series of three articles dedicated to the introduction of aluminium sulfate as a chemical for chemical removal of phosphorus compounds from wastewater. The urgency of the task of eliminating nutrients from wastewater is described; the primary concern of removing phosphorus for the protection of water bodies from eutrophication is substantiated. A short literature review including the practice of chemical removal of phosphorus from wastewater in USA and European Union is presented. Special features of the basic chemicals – calcium, aluminium and iron compounds – essential for the practical application of chemical removal of phosphorus are described. The second article will present the evaluation of the toxicity of aluminium and iron compounds; the results of investigating the impact of iron and aluminium salts on the aeration tank biocenosis and sludge mixture dewaterability will be discussed. The third final article will present a detailed report on the introduction of aluminium sulfate as a chemical for chemical removal of phosphorus compounds from wastewater at the Saint-Petersburg wastewater treatment facilities.

Key words

wastewater , aluminium sulphate , nutrients removal , chemical precipitation of phosphorus , ferric sulfate , insoluble phosphates