Biological Pre-treatment

Treatments of landfill leachate in a two-stage RO system with biological pre-treatment have been also proposed (Linde et al., 1995). In this case tubular membranes were used in the first step to reduce membrane fouling of RO spiral wound membranes used in the second stage. An improvement of this process can be obtained by replacing the RO unit in the first stage by a NF unit with a consequent decrease in operating costs (Peters, 1998). 

It has been found that partial oxidation is satisfactoiy as a pre-treatment to biological or carbon adsorption treatment. Partial oxidation often seems to make recalcitrant organics easier to degrade biologically and easier to adsorb. 

Bermejo-Barrera P, I Ernanuez-Nocelo S, Moreda-PiSeiro A and Bekmejo-Barrera A (1999) Useftilness of enzymatic hydrolysis procedures based on the use of pronase E as sample pre-treatment for multi-element determination in biological materials. J Anal At Spcctrom 14 1893-1900. 

Another pre-treatment often used to prevent biological degradation of organic contaminants in water is acidification with sulfuric acid to pH <3 [4], The change in concentrations of NPEO, AEOs and PEGs in spiked groundwater (500 p,gL 1) and in wastewater treatment plant (WWTP) influent preserved by addition of formaline (1 and 3%, v/v) and by acidification to pH 3 with sulfuric acid and kept for 30 days at 4°C are shown in Table 4.4.1. 

The possible biological components fall into two main categories (Table 4.5) and their function is to recognize and bind a specific analyte. It is the properties of the biological component that give specificity to biosensors and make them suitable for the analysis of samples without pre-treatment. 

Pre-treatments, Extraction and Clean-Up for Human Biological Samples. 346... 

The aim of this section is to present a concise overview of separation, concentration and decomposition methods for sample pre-treatment and an overview of the analytical methods available for determining free inorganic fluoride and total fluorine in the environment (natural and drinking water, air and soil), biological and related materials, and fluoride supplements and dental products. 

J. Qvarnstrom, W. Freeh, Mercury species transformations during sample pre-treatment of biological tissues studied by HPLC-ICP-MS, J. Anal. Atom. Spectrom., 17 (2002), 1486-1491. 

In many cases, the most appropriated use of AOP may be as a stage of a combined biological/chemical process. AOP can be used as pre-treatment step to enhance biodegradability of the waste or as a complementary treatment to remove residual bio-refractory component if the biological treatment is not adequate to ensure the water-quality standards. 

Several different peroxygen-based systems exist, all of which are compatible with biological treatment. The peroxygen treatment can be used up- or downstream of the biotreatment unit, either as a pre-treatment to reduce toxicity and improve biodegradability or as a post/polishing treatment to remove remaining biorecalcitrant species from the effluent. All the peroxygen-based treatments can also be used as stand-alone processes for the total treatment of a waste stream. The most common AOPs are ... 

ICh tests have many advantages they are very sensitive, rapid, do not require pre-treatment of the biological material (which they are designed to analyse), and use small quantities (0.01-0.1 mL) of body fluids. Their principal drawback is low specificity. 

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