AboutDavid L. Russell, PE Expertise I`m a Chemical,Civil and Environmental Engineer and have a number of projects in all phases of the environment.
I have worked in the chemical industry and am active in professional societies, and am currently on an industrial wastes committee for the Water Environment Federation, and have taught courses in remediation in the US and abroad.
I have written one book on Remediation of petroleum Contaminated Sites, and have a second book on PRACTICAL WASTEWATER TREATMENT to be published by John Wiley in September, 2006. I've also written over 30 articles on various elements of environmental problems and cleanup. Most Recently, I have addressed a NATO Scientific and Techical Conference on Ecoterrorism, and have worked with the same group on remediation of sites contaminated with Chemical Warfare Agent materials and othe materials as well. . I can answer q`s about Chemical and Environmental Engineering, land development, air pollution, water pollution, soil and water cleanup, combustion, international environmental problems, industrial processes chemical processes. Civil and Environmental and Chemical Engineering. Overall, I have over 35 years of experience in this area. Note: I do not answer homework questions
Experience I love work in the third world and developing areas
because it is challenging and one can get a sense of accomplishment.
Question What is the 1st priority treatment for sewerage water which must be done before any other treatments?
Answer The first two orders of the day in dealing with sewerage are removal of the coarse solids by a bar screen and grit removal. The bar screen is designed to remove large solids over about 10 mm diameter, including such things as logs, rocks, sofas (yes, there have been instances when sofas were stuffed down a sewer), and even parts of bodies (there was another instance where an artificial hip joint was found in a communitor (a device for grinding large solids down to managable size= 10mm or less, and that led to a murder conviction of the deceased's gay lover). So the first step is to remove the coarse solids larger than about 10 mm.
The second step is to remove the grit and the sand because it tears up the pumps. This is done in a grit chamber which is a quiet place with a fixed retention time, used to drop sand and grit (sg.=2.65) out of the sewerage.
After that the processes are dependent upon the overall treatment system selected. Some processes use clarification (sedimentation) as a next step to remove about 30% of the organic load. That is often followed with some type of aeration.
Other processes start with aeration and try and oxidize the entire organic load.
So there you have it. The initial processing steps in wastewater treatment.
