Wastewater biological treatment

Magnesium ion poses no threat to the environment and in fact may have a beneficial impact as it is a minor nutrient essential for plant growth. Accidental spills of magnesium hydroxide will not create any significant damage since the material is not caustic. Spills of lime, hydrated lime, and sodium hydroxide are very caustic chemicals and can cause immediate environmental damage, both to plant and animal life. 

Many wastewater treatment plants use some form of biological treatment to reduce the levels of biodegradable organic substances. These biological 

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Ex situ bioremediation may use various biological wastewater treatment processes, soil piles, or land appHcation. With in situ bioremediation, the basic process is the same microbes, soil, and water working together as a bioreactor. Where the in situ techniques differ are in how contaminants and microbes are brought in contact and how oxygen, nutrients, and other chemical supplements ate distributed in the soil—water—air matrix. Typical in situ bioremediation techniques include natural or intrinsic attenuation, air sparging, and bioventing. 

U.S. Environmental Protection Agency, Process Control Manualfor Aerobic Biological Wastewater Treatment Facilities, Office of Water Program Operations, Washington, D.C., EPA-430/9—77—006, 1977. 

Biological wastewater treatment processes also affect solids characteristics and hence solids separation. Activated sludge solids have been found to have a distinct bimodal distribution with one mode in the supracolloidal to settleable range and another near the border between the colloidal and supracolloidal fractions. The concentrations and size limits in each range are affected by conditions in the... 

Henze M, van Loosdrecht MCM, Ekama GA, Brdjanovic D (2008) Biological wastewater treatment principles, modelling and design. IWA Publishing (ISBN 9781843391883), pp 528... 

Many studies have confirmed a complete biodegradation of ibuprofen to hydroxy-ibuprofen and carboxy-ibuprofen in biological wastewater treatment, whereas removals higher than 95% have been reached [17,49,50]. For diclofenac, contradictory results have been reported for its removal during CAS wastewater treatment. In some WWTPs, attenuation of 50-70% of diclofenac was reported [6, 10, 11, 51, 52], whereas some smdies showed extremely low efficiency of conventional treatment (only 10-30% removal) [49, 53]. 

Joss A, Keller E, Alder AC, Gobel A, McArdell CS, Temes T, Slegrlst H (2005) Removal of pharmaceuticals and fragrances in biological wastewater treatment. Water Res 39(14) 3139-3152... 

Model-based optimization of a sequencing batch reactor for advanced biological wastewater treatment... 

The application of a dynamic PCA strategy to a full-scale industrial wastewater treatment plant has demonstrated the feasibility and effectiveness of the proposed dynamic process monitoring approach. The methodology is relatively simple, only based on the historical operation data sets, and can easily be applied to most biological wastewater treatment processes. 

Although some of the examples used for illustration in Chapter 14 impinge on biological wastewater treatment technology, a systematic acconnt of these lies beyond the scope of this volume and the competence of the anthors. It is worth noting, however, that anaerobic reactors that are developed to treat wastewater with the object of producing methane may... 

Flow to the deep shaft biological wastewater treatment plant is screened and goes through a DAF unit for fiber removal prior to entry into the deep shaft. The Ohtsu plant consists of one shaft 2.79 m (110 in.) in diameter by 100 m (330 ft) deep. The shaft design incorporates one downcomer and one riser where the downcomer is located concentrically within the shaft with the resultant annular volume serving as the riser. Mixed liquor in the shaft is maintained at approximately 5000 mg/L and the hydraulic detention time in the shaft is 1 h. Mixed liquor enters the head tank at the top of the shaft where gas disengagement occurs. The head tank is 6mxl2mx3m... 

Section 27.8 summarizes the feasibility and advantages of an improved biological wastewater treatment system involving the use of secondary flotation clarification. 

Commercially Available DAF and DAFF Clarifiers for Biological Wastewater Treatment Systems... 

Table 26.1 provides a summary of the main features of biological wastewater treatment. 

Holbrook RD, Love NG, Novak JT (2004) Sorption of 17-beta-estradiol and 17 alpha-ethinylestradiol by colloidal organic carbon derived from biological wastewater treatment systems. Environ Sci Technol 38 3322-3329... 

Koh YKK, Chiu TY, Boobis AR, Scrimshaw MD, Bagnall JP, Soares A, Pollard S, Cartmell E, Lester JN (2009) Influence of operating parameters on the biodegradation of steroid estrogens and nonylphenolic compounds during biological wastewater treatment processes. Environ Sci Technol 43 6646-6654... 

Pharmaceuticals comprise one of the most common groups of organic microcontaminants present in biosolids, given that conventional biological wastewater treatment processes are inadequate for their complete removal [132],... 

Horan, N. J., Biological Wastewater Treatment Systems, John Wiley Sons, Chichester, England, 1990, 234. 

Microbial processes in terms of sludge (biomass) production, BOD and nutrient removal have been focused on when dealing with biological wastewater treatment. Therefore, and because the sewer is the system for input to the wastewater treatment plant, there is a basis as well as a perspective to establish a process concept for the sewer that can be integrated with the activated sludge processes. 

A new in situ probe [25] was presented for the continuous measurement of ammonium and nitrate in a biological wastewater treatment plant. Based on the use of electrochemical measurement, the sensor can be immersed and requires minimum maintenance. The tests carried out to compare its performance with those of other procedures (including UV for nitrate) showed that the results were rather close, with a detection limit of 0.1 mg L 1 for both analytes. 

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