China
Africa
Biological Wastewater Treatment
By C. P. Leslie Grady, Jr., Glen T. Daigger, Nancy G. Love, Carlos D. M. Filipe
Following in the footsteps of previous highly successful and useful editions, Biological Wastewater Treatment, Third Edition presents the theoretical principles and design procedures for biochemical operations used in wastewater treatment processes. It reflects important changes and advancements in the field, such as a revised treatment of the microbiology and kinetics of nutrient removal and an update of the simulation of biological phosphorous removal with a more contemporary model.
See what’s new in the Third Edition:
- A chapter devoted to the description and simulation of anaerobic bioreactors
- Coverage of applications of submerged attached growth bioreactors
- Expanded discussion of modeling attached growth systems
- Increased information on the fate and effects of trace contaminants as they relate to xenobiotic organic chemicals
- A chapter on applying biochemical unit operations to design systems for greater sustainability
The book describes named biochemical operations in terms of treatment objectives, biochemical environment, and reactor configuration; introduces the format and notation used throughout the text; and presents the basic stoichiometry and kinetics of microbial reactions that are key to quantitative descriptions of biochemical operations. It then examines the stoichiometry and kinetics used to investigate the theoretical performance of biological reactors containing microorganisms suspended in the wastewater. The authors apply this theory to the operations introduced, taking care to highlight the practical constraints that ensure system functionality in the real world.
The authors focus on further biochemical operations in which microorganisms grow attached to solid surfaces, adding complexity to the analysis, even though the operations are often simpler in application. They conclude with a look to the future, introducing the fate and effects of xenobiotic and trace contaminants in wastewater treatment systems and examining how the application of biochemical operations can lead to a more sustainable world.
Practical Applications of Hydrogen Peroxide for Wastewater Treatment
The increased environmental awareness requires reviewing production technologies and waste treatment processes differently. Previously disposed of waste has to be looked at again to verify whether its disposal meets current regulations.
The chemical destruction of waste products shows that it can solve past, present and future problems. Chemical treatments based on hydrogen peroxide (H2O2) or other active oxygen (AO) products (e.g. sodium percarbonate, sodium chlorate, etc.) are environmentally safe, effective and do not create hazardous byproducts.
Wastewater treatment systems based on H2O2 or AO products can be grouped into three (3) categories.
Municipal Wastewater Treatment
H2S abatement, peak or emergency oxygen supply, algae, slime and filamentous control.
Industrial Wastewater Treatment
Destruction of cyanide, phenol, sulfide, sulfite, hypochlorite, formaldehyde, nitrite, etc.
Developmental Water Treatment
Ozone – H2O2 peroxidation of drinking water, UV/H2O2 or UV/H2O2/O3 for water detoxification and H2O2 for bioremediation. [13]
Activated Carbon Adsorption For Wastewater Treatment
in Activated Carbon Adsorption For Wastewater Treatment
This volume is a guide to the state of the art of activated carbon adsorption technology as applied to wastewater treatment. This book surveys this body of knowledge and is a detailed description of current technology.
1. Wastewater Characteristics and Treatment
2. Activated Carbon
3. Activated Carbon Adsorption
4A. Development of Design Parameters
4B.Development of Design Parameters
5. Contacting Systems
6A. Regeneration Systems
6B. Regeneration Systems
7. Total Process Design and Economics
8. Component Equipment Design
9. A Guideline to Operational Procedures and Design for Granular Carbon Systems Wastewater Applications
10. Safety Aspects of Activated Carbon Technology
Aerobic digestion of sewage sludge for waste treatment
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects
Although Saudi Arabia is producing high gross national income per year in the Jeddah city, the sewage treatment and disposal systems does not meet the needs of people sufficiently. The disposal and industrial solid waste treatment and the collection of municipal sewage have been creating problems for a long time in Jeddah. The predictions showed that only 25% of raw sewage has been treated and cesspool system usage is still very common which increases underground water level. Moreover, the investigations depicted that the current location is unsuitable for the sewage and industrial dumping. In this sense, the processes of aerobic digestion carry out the organics through the presence of oxygen. It is well known that as a biological process, aerobic sludge digestion occurs in the existence of oxygen and in this process the bacteria in activated sludge consumes organic matter with oxygen and converts them into carbon dioxide. The achievement of aerobic digestion depends on using diffuser systems or jet aerator for sludge oxidation. The bubble diffusing is a cost-efficient diffusion method, however plugging occurs problems mainly due to sediment trapped in smaller air holes. The positive displacement blowers provides air with high volumes two digesters to establish aerobic conditions. Under these conditions, the bacteria digest the organic substances in the mixture quickly and convert them into carbon dioxide and others. For the reduction of pathogen content, elimination of offensive odors, and reduction/elimination of the putrefaction, during the processing the sludge is stabilized. The stabilization technologies are the lime stabilization, heat treatment, aerobic digestion, anaerobic digestion and composting. The composting process includes the aerobic degradation of organic matters and aerobic microorganisms which converting the organic matters into carbon dioxide and leaving relatively stable odor free has value for fertilizer products.
Evaluation of optimal dose and mixing regime for alum treatment of Matthiesen Creek inflow to Jameson Lake, Washington
Published in Lake and Reservoir Management
Churchill, J.J., M.W. Beutel and P.S. Burgoon. 2009. Evaluation of optimal dose and mixing regime for alum treatment of Matthiesen Creek inflow to Jameson Lake, Washington. Lake Reserv. Manage. 25:102–110.
An innovative method of reducing external phosphorus (P) loading to lakes uses engineered systems to treat lake inflows with aluminum sulfate (alum). In this study we used a series of jar tests to examine the optimal alum dose and mixing regime to remove P from Matthiesen Creek, an important external source of P to Jameson Lake. Matthiesen Creek is a good candidate for alum treatment because the creek runs year round, and the majority of P in the spring-feed creek is in the form of bioavailable dissolved P that can be efficiently captured in alum floc. The mixing regimes in this study mimicked a range of possible treatment scenarios that relied on natural turbulence in the creek or conventional mechanical mixing, and presumed the discharge of alum floc either directly to the lake or to an on-shore settling basin. Jar tests showed that an alum dose of 5 mg-Al/L was sufficient to decrease P from around 0.13 mg-P/L to below 0.02 mg-P/L for most mixing regimes. For all mixing regimes, doses of up to 20 mg-Al/L did not depress pH below the recommended minimum pH of 6. Flash mixing prior to low-intensity mixing did not enhance P removal over low-intensity mixing alone, but flash mixing alone resulted in lower levels of P removal from creek water. Jar testing with a mixture of alum-treated creek water and lake water showed that lake waters tended to inhibit P uptake by alum floc. This, combined with the fact that high pH favors the formation of the aluminate ion which could exhibit chronic toxicity to aquatic biota, suggests that discharge of alum solids directly to the lake should be avoided. We recommend an engineered inflow treatment system on Matthiesen Creek that maintains an alum dose of 5–10 mg-Al/L under moderate mixing conditions (Gt of 1,000–3,000) with alum floc collected in an on-shore settling basin.
The design for wastewater treatment plant (WWTP) with GPS X modelling
Published in Cogent Engineering
Wastewater treatment is a process, which is being done on the wastewater to change its quality for drinking or other suitable purposes. Wastewater treatment takes place in wastewater treatment plants, which should be designed under different circumstances. The criteria are being considered in this design for wastewater treatment plant (WWTP) Al-Hay. Moreover, the characteristics of physical, chemical and biological wastewater also are described. Based on the population of Al-Hay city, the project is undertaken to design a wastewater treatment plant. The girt chamber, equalization basin, oil and grease removal, aeration tank and secondary settling tank have been designed, and then the values for mean cell residence time, volume of aeration tank, hydraulic retention time, F/M ratio, return sludge flow rate, sludge production and oxygen requirement have been calculated. Modelling using GPS X also has been done on this data. It is exhibited a typical diagram of WWTP staring with influent flow, aeration tank and settling (clarifier) tank. The simulation time is also illustrated. With increasing the time, the parameters such as TSS and solids are typically enhanced. This is as indicator to improve the fit of the model and the actual data for the secondary effluent TSS. The research shows the treatment process design of Al-Hay wastewater treatment plant (WWTP). The paper also described the equations process design for WWTP. Sludge age (θc) has been calculated and associated to the observed yield (Yobs). There is correlation between sludge age and the mixed liquor suspended solid (MLSS). The value of the observed yield has been noticed, with values ranging from 0.2 to 0.6 kgVSS/kg(BOD5). The sludge retention time is equal to 27.7 day and the sludge produce is 3339.18 Kg/day. These results are related to biological tank for Al-hay WWTP is worked during with high efficiency.