Hi there;
Maybe any sewage onsite disposal system experts out there? What options do you have if 2' of silty clay loam / massive over impervious layer (clay). 3 out of 4 perc tests show infinite perc time. According to the local practice manual this soil is unsuitable for onsite systems -...
to bimr,
I understand the systematic of waterhammer and what to do normally. And I agree that the upslope section of this forcemain can be subject to waterhammer that needs attention. But I was questioning the usage of the mentioned: (cit) "...spring-loaded valve at the end that would close...
hi gordini,
I don't understand the point of the valve in option 3. Why would you want to keep the pipe full at all times? Take option 2 and off you go. Instead of a air release valve you will need a combination air valve to allow air into the pipe after the pumps stop. This will allow draining...
Hi bimr,
I haven't seen the official results yet but the lab said that P would be in the 60 - 70 mg/l. That's a lot but could it cause the following problem: the plant does not build up any biomass - virtually clear of solids although reseeded a few times. pH and DO are ok and the plant used to...
Hi Eng's,
how can an unusual high P level in a treatment plant influent cause harm to the plant's operation? Can high P upset the plant? Which levels are critical for extended aeration plants with no advanced treatment? What's the solution? Pricipitation prior in the equalization tank? Thanks!
Hi out there,
I got a similar but yet different question than a few threads earlier here: I am looking at a proposed sewage forcemain which will convey the wwater about 8 km to the nearest municipal system. To about 4 km down of the pumpstation, the forcemain has a continuous rising grade...
Hi there,
Does anybody know about a table with chlorine concentrations in water (swim pool) and impacts on humans? Normal, max. allowed ... lethal...? Something down that line? Thanks!
won13,
I have recently done a waterhammer study on a 150 mm PVC SDR 26 pipe and its critical negative pressure was -313 kPa. I would assume that a C900 8" is at least this. Good luck!
Hi there!
Quick question: I am designing a water booster pumpstation, using multiple stage axial split centrifugal pumps (due to 500 ft head). How can I determine how close the suction pipes can be situated to each other if coming off a main suction header. Is there a rule of thumb or any fancy...
Pipe jacking:
There are several jacking systems available for smaller pipe sizes which usually utilize some kind of drill head to loosen the ground and a screw to transport the displaced soil to the start excavation. A pressing station in the start excavation pushes the jacking pipes gradually...
Hi Eng's;
Can you guys tell me a bit from your experience when you would prefer which of these two pump types when designing a new water system? Would topography/hydraulic have an impact on the decision?
Does anybody have the ACI 302.1R, 6.4.4 Chapter 7 available and would send it to me? I need that urgently until 13 June for a court case! Thanx a lot!
cmoch@umagroup.com
(250)475-6355
I wouldn't go smaller than 6" in size. Definitely you want to determine the more relevant average daily flow through the pipe and check the velocity at x% full status. This velocity should be min. 2'/sec if you want to avoid sedimentation and potential odour problems.
What number of fecal coliforms can one expect to be dicharged from a activated sludge - sewage treatment plant? Just a common number! Does 200 per 100ml sound alright?
Hi Eng's,
Is there an older engineer out there who can still handle a waterhammer analysis as described in John Parmakian 1963? I have tried to do the graphical solution starting with using the charts in paragraph 48, page 87-92. I calculated the two necessary parameter for the charts (2*rho...
Could anybody send me a list of symbols being used in Northamerica for generating Process and Instrumentation Diagrams (for wastewater treatment plant). Or could anybody confirm that the symbols are the same like in the european standards?
email: cmoch@umagroup.com
fax: (250) 475-6388
Thanks...
Hi Eng's!
Can somebody tell me or give me link to an accepted method of doing a waterhammer analysis by hand? The situation is a sewer forcemain of app. 800m lenght between two liftstations - cont. up-slope. Especially I would like to determine the low-pressure curve over the entire pipe! Is...