A Study On The Characteristics Of Calcium Enrichment And Its Effect On Activated Sludge In Dyeing Wastewater Biological Treatment System

The dyeing wastewater must be gone through many chemical and physical pretreatments before entering into the biochemistry processing because of its complex conditions.Some exogenous inorganic ions could have an impact on the operation effect of the treatment because of these modifiers.It is important to study the interactions between the typical inorganic ions and the microorganisms which live in the activated sludge.This article investigated some major inorganic ions and chose calcium as the object of this study.Based on the dyeing wastewater biological treatment system,the influence of calcium concentration in effluent quality,the nature of the activated sludge and the functional diversity of microbial community was investigated.The purpose of this study was to provide the reference basis knowledge for the process of dyeing wastewater treatment and recycling.Based on the investigation of different stages of the printing and dyeing wastewater treatment process,we could know calcium is one of the major metallic elements with its 102 mg/L concentration.Well,the activated sludge showed up obvious adsorption for calcium in the static experiment with the adsorption of 8.81mg/g.Constructing a system of printing and dyeing wastewater biological treatment according to the actual processing.Studying the enrichment features of calcium,purifying effect of treatment,activated sludge characteristics and metabolic function of microbial communities with 3 different concentrations of calcium in the aerobic tank by the dynamic experiment.We could conclude that the normally running time of treatment system of 3 studies,130mg/L,250 mg/L and 500 mg/L,was 21 d,10d and 5d respectively.The maximum accumulation of calcium in the activated sludge during the treatment systems running was 30.12mg/g,2.78 mg/g and 2.36 mg/g.The increasing concentration of calcium in the water will reduce the time of biological treatment system and stable operation.The activated sludge could enrich calcium effectively.The maximum accumulation would decrease in the sludge with the increasing calcium in the wastewater.This research showed the influence of different calcium concentrations in influent on the functional diversity of microbial community in the activated sludge using the Biolog eco-plate technology.The microbial metabolic activity of activated sludge was reduced suffered from the 130mg/L concentration of calcium.The Shannon index,McIntosh index and Simpson index low observably.The ability of carbon source utilization reduced with the 130mg/L concentration.When the concentration in the inflow was 250mg/L,the AWCD value,diversity indexes and the carbon sources utilization expect to carboxylic acids would be enhanced.When the concentration in the inflow was 500mg/L,the AWCD value and diversity indexes showed no significant changes.The microorganisms strengthen utilization of carbohydrates,polymers and amines,yet weaken the utilization of amino acids,carboxylic acid and phenols.It shows that proper concentration of calcium could strengthen the metabolic activity and function diversity of microorganisms in active sludge.