Biological purification

Niers A process for treating the aqueous effluent from dyeworks by a combination of chemical precipitation and biological purification. 

Urushigawa Y, Yonezawa Y. 1979. Chemico-biological interactions in biological purification systems VI. Relation between biodegradation rate constants of di-n-alkyl phthalate esters and their retention times in reverse phase partition chromatography. Chemosphere 5 317-320. 

Pauli O, Franke G. 1971. Behaviour and degradation of technical preservatives in the biological purification of sewage. In Proceedings of the 2nd International Biodeter Symposium. Biodeter Mater, 52-60. 

Yonezawa, Y. and Y. Urushigawa. 1979. Chemicobiological interactions in biological purification system. V. Relation between biodegradation rate constants of aliphatic alcohols by activated sludge and their partition coefficients in 1-octanol-water system. Chemosphere 3 139-142. 

Acids and alkalis that may corrode pipes, pumps, and treatment units, interfere with settling, upset the biological purification of sewage, release odors, and intensify color. 

Urushigawa, Y., and Y. Yonezawa (1979), Chemicobiological Interactions in Biological Purification System VI. Relation between Biodegradation Rate Constants of Di-u alkyl Phthalate Esters and Their Retention Times in Reverse Phase Partition Chromatography, Chemosphere 5, 317-320. 

The first free-flow electrophoresis device (1 ) was designed specifically for large scale biologicals purifications and, although that unit never became fully operational, it preceded a plethora of innovative instruments which either resolved or eliminated the drawbacks inherent in the earliest device. For instance, one apparatus which has been commercially available since the early sixties, the thin-film device (2j is successfully operated at both analytical and preparative scales, e.g. 

Chaetoceros lauderi, Skeletonema costatum, Nitzschia spp.) contribute to the biological purification of the marine environment and are responsible for the destruction of terrestrial bacteria in the open sea. 

Urushigawa Y, Yonezawa Y. 1979. Chemico-biological interactions in biological purification systems ... 

Chemical oxidation can be used as a pretreatment in combination with biological purification leading to the breakdown of components that are difficult to degrade. Another possibility is a partial oxidation of the sludge resulting in limited sludge production. 

When the wastewater is discharged, excessive amounts of oxidizing should be avoided. Overdosage must be avoided, as it could have a negative impact on subsequent biological purification. Most oxidants are not selective requiring a purification step (e.g., filtration) or leading only to partial oxidation. 

Several laboratory studies have also been realized in gas-liquid-solid reactors. They are concerned with the oxidation of pure liquids (cyclohexane, ethylbenzene, tetralin, cumene, etc...) or of diluted aqueous solutions. In this fiels, the oxidation of wastewater in trickle-bed reactor has been proposed as an alternative to biological purification. 

Rapid biological decomposition of aromatics is necessary for biological purification of effluents rich in aromatics. 

USE OF AFFINITY CHROMATOGRAPHY IN MOLECULAR BIOLOGY Purification of mRNA... 

Industrially the chances of successful biodegradation of these stubborn compounds (with no predominant atmospheric stripping) depends on tight control of the biological purification unit, Among other parameters, sludge of sufficient age must be maintained see Chapter 3),... 

In biological purification, where the HC are chiefly dissolved, a spectrophotometric method specifying a reading of all the peaks (e.g. AFNOR T 90-114). 

Tiiese products, with an oxidation number of 2.5, are presented in the literature as the j final oxidation stage of thiosulfates in aerobic biological purification where enzymes act to- achieve more complete oxidation (autotrophic microorganisms of the thiobacillus thioxidans type). ... 

Nonbiodegradable dissolved organic COD conesponds to macromoleculat OM that is unaffected by biological purification (e.g. sulfonates and naphthenates). It can be measured by slow percolation (space velocity of 2) on granular activated carbon (GAC). 

Inorganic COD of sulfur compounds that may have withstood biological purification. (S20] i Si Og ) should represent residual COD after filtration on granular activated carbon. It can be titrated by ion-exclusion chromatography. 

In aerobic biological purification, the contact with a mass of bacteria can also have a considerable catalytic" effect related to enzyme action. This time the advantage per se would not be a reduction in oxidation time (oxidation rime is governed by the oxidation of OM) but the final SO 4 stage which would be prohibitive by chemical means. 

Reaction (4) which is used for effluents of sulfonation processes can be developed by biological means. However, the degradability of benzo-sulfonic acids, like that of aromatic hydrocarbons, is very slow and requires very small loading masses. Satisfactory efficiency can be achieved in two-staged serial biological purification. 

Sulfides have a certain inhibiting effect on biological purification, or can at least limit the development of some strains of bacteria and delay the breakdown of some BOD5 components (phenols, SCN ). 

Biological purification which removes the biodegradable fraction of dissolved or solubilized HC. 

This purification process is the intermediate phase between preliminary oil removal (API or lamella separators) and biological purification. 

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