TVT-BIO

Basic Microbiology For Wastewater Treatment

Bacteria, Microorganisms, Micro-animals Bacteria are a diverse group of single-celled organisms, most of which are microscopic. Bacteria occur in soil, water, and air, and as symbionts, parasites or pathogens of man and other animals and plants.
Bacteria are either aerobes-growing in the presence of air or oxygen, or are anaerobes-growing without air or oxygen. Some bacteria are "switch-hitters" who can switch to grow from one environment (air or air-less) to the other.
Besides bacteria, other microorganisms such as fungi (yeasts), protozoa, and micro-animals such as rotifers work in concert to affect water quality.

Images © Wim van Egmond E-mail: egmond@tip.nl

BOD, COD & DO Water quality has a number of constituents including biological oxygen demand (BOD), chemical oxygen demand (COD).
Natural organic detritus and organic waste from wastewater treatment plants, failing septic systems, and agricultural and urban runoff, are a food source for water-borne bacteria. Bacteria consume these organic materials using dissolved oxygen, thus reducing the dissolved oxygen (DO) present for fish and other aquatic life. BOD is a measure of the amount of oxygen that bacteria will consume under aerobic conditions.
COD does not differentiate between biologically available and inert organic matter, and it is a measure of the total quantity of oxygen required to chemically break down (oxidize) all organic material into carbon dioxide and water. COD values are always greater than BOD values, but COD measurements can be made in a few hours while BOD measurements take five days.

Wastewater Treatment Plants The main focus of wastewater treatment plants is to reduce the BOD and COD in the effluent discharged to natural waters, meeting state and federal discharge criteria. Wastewater treatment plants are designed to function as "microbiology farms," where bacteria and other microorganisms are fed oxygen and organic waste.
Treatment of wastewater usually involves biological processes such as the activated sludge system in the secondary stage after preliminary screening to remove coarse particles and primary sedimentation that settles out suspended solids. These secondary treatment steps are generally considered environmental biotechnologies that harness natural self-purification processes contained in bioreactors for the biodegradation of organic matter and bioconversion of soluble nutrients in the wastewater.

Application Specific Microbiology Each wastewater stream is unique, and so too are the community of microorganisms that process it. This "application-specific microbiology" is the preferred methodology in wastewater treatment affecting the efficiency of biological nutrient removal. The right laboratory-prepared bugs are more efficient in organics removal-if they have the right growth environment. This efficiency is multiplied if microorganisms are allowed to grow as a layer-a biofilm-on specifically designed support media. In this way, optimized biological processing of a waste stream can occur. To reduce the start up phase for growing a mature biofilm one can also purchase "application specific bacterial cultures" from appropriate microbiology vendors.

Site Specific Bacteria Aeration and biofilm building are the key operational parameters that contribute to the efficient degradation of organic matter (BOD/COD removal). Over time the application specific bacteria become site specific as the biofilm develops and matures and is even more efficient in treating that site-specific waste stream.
Efficient processing of waste is therefore a cost saving opportunity in operations that will add to your bottom line.

For more Microbiology Click Here

For more Microbiology Click Here
BOD, COD & DO	Water quality has a number of constituents including biological oxygen demand (BOD), chemical oxygen demand (COD). Natural organic detritus and organic waste from wastewater treatment plants, failing septic systems, and agricultural and urban runoff, are a food source for water-borne bacteria. Bacteria consume these organic materials using dissolved oxygen, thus reducing the dissolved oxygen (DO) present for fish and other aquatic life. BOD is a measure of the amount of oxygen that bacteria will consume under aerobic conditions. COD does not differentiate between biologically available and inert organic matter, and it is a measure of the total quantity of oxygen required to chemically break down (oxidize) all organic material into carbon dioxide and water. COD values are always greater than BOD values, but COD measurements can be made in a few hours while BOD measurements take five days.
Wastewater Treatment Plants	The main focus of wastewater treatment plants is to reduce the BOD and COD in the effluent discharged to natural waters, meeting state and federal discharge criteria. Wastewater treatment plants are designed to function as "microbiology farms," where bacteria and other microorganisms are fed oxygen and organic waste. Treatment of wastewater usually involves biological processes such as the activated sludge system in the secondary stage after preliminary screening to remove coarse particles and primary sedimentation that settles out suspended solids. These secondary treatment steps are generally considered environmental biotechnologies that harness natural self-purification processes contained in bioreactors for the biodegradation of organic matter and bioconversion of soluble nutrients in the wastewater.
Application Specific Microbiology	Each wastewater stream is unique, and so too are the community of microorganisms that process it. This "application-specific microbiology" is the preferred methodology in wastewater treatment affecting the efficiency of biological nutrient removal. The right laboratory-prepared bugs are more efficient in organics removal-if they have the right growth environment. This efficiency is multiplied if microorganisms are allowed to grow as a layer-a biofilm-on specifically designed support media. In this way, optimized biological processing of a waste stream can occur. To reduce the start up phase for growing a mature biofilm one can also purchase "application specific bacterial cultures" from appropriate microbiology vendors.
Site Specific Bacteria	Aeration and biofilm building are the key operational parameters that contribute to the efficient degradation of organic matter (BOD/COD removal). Over time the application specific bacteria become site specific as the biofilm develops and matures and is even more efficient in treating that site-specific waste stream. Efficient processing of waste is therefore a cost saving opportunity in operations that will add to your bottom line.