Water & Wastewater Treatment Forum - Water and Wastewater.com Help Forums

Water & Wastewater Treatment Forum - Water and Wastewater.com Help Forums http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?board=general Water & Wastewater Treatment Forum - Water and Wastewater.com Help Forums en-us Water and Wastewater.com Help Forums Tue, 21 May 2013 11:36:07 +0000 http://blogs.law.harvard.edu/tech/rss 30 Sludge Bulking in Restaurant Aeration System http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369088212 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369088212 Mon, 20 May 2013 17:16:52 +0000 I "designed" a simple aeration tank for a small restaurant served by a very old and undersized leach field. The aeration tank consists of a 1 HP Tsurami submersible aerator in a 2500-gal septic tank, with the last 700 gals (separate compartment) used for sludge settlement and sludge return. There is no baffle on the outlet of the settling compartment. The aeration tank is preceeded by a 3,000-gal grease trap and 4,000-gal septic tank, and is followed by and existing 2,000-gal septic tank. The design data/assumptions are: Avg Daily Flow = 1000 gpd (metered) Peak Daily Flow = 1800 gpd (metered) BOD5 = Assumed to be 1,000 mg/l Oxygen applied = 1 lb O2 per 1b of BOD @ Peak Day Sludge Return Flowrate = 0.5x average daily flow Cost = $18,000 The intent of the aerator was first, to aid in grease removal (a similar system with zero sludge return has worked well at another restaurant). I added a simple sludge return pump to this design to help knock down the BOD and extend the life of the existing leach bed. Operation/setting adjustments to be done peroidically "by eye" (color, foam, etc.) per the owner's desire to minimize costs. Shortly after start-up, there was 2 feet of white foam on top of the aeration chamber which I'm told is common at start-up. Now, about 4 month laters the foam is gone and there is a 6" thick sludge (brown/black) blanket on the surface of the sludge compartment. There is no foam in the aeration tank at all. It was also discovered that the sludge return pump was not operating even though the run-time meter said indicated that it was. Also, the grease trap had clogged is such a way that the grease spilled into the aeration. Question: Do you feel that that grease overflow plus lack of sludge return created the sludge bulking issue? Will increasing the sludge return flowrate help if the problem persists. Recall that the other system had zero sludge return and has had no sludge bulking problem at all. Thanks for any input. labs anaerobic degradation http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369080913 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369080913 Mon, 20 May 2013 15:15:13 +0000 Hi, I am looking for labs in the US (preferably west coast) that can do anaerobic biodegradation tests on wastewater. I need to have an idea on COD reduction potential (and some ideas on kinetics of this aspect) as well on biogas production (& Biogas composition, if possible). who can provide me with a list of some 5 (or more) good labs that do this? thanks in advance! Centrifuge Replacment Recommendation http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1358820267 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1358820267 Mon, 20 May 2013 10:55:49 +0000 Many companies have mobile test units. Fournier, Prime Solutions and FKC all came to our plant for a small fee <$2,500. It was helpful to see the units in operation and the maintenance required. biodegradability of PTA wastewater http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368689444 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368689444 Mon, 20 May 2013 10:50:43 +0000 Touche grrun that is spot on. Another question is that if you have a COD limit in your discharge permit, does the lab method allow for filtering out suspended solids so you are only capturing the dissolved COD? if not then poor clarifier performance could give you heartache on TSS and COD limits at the outfall. Aeration basin getting too cold? http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368736255 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368736255 Mon, 20 May 2013 10:45:46 +0000 thanks for the replies.  Yes my AST's are above ground tanks that are insulated on the shell. Unfortunatley the mechanical aeration system does turn into a whole lot of cooling but the plant is not likely to spend the capital to convert them to fine bubble aeration (in spite of my insistence that they would be much better off and save significantly on steam in the winter) Thanks for the advice on running at a lower DO... I hadn't thought of that but will put that in the "crisis plan". Forgot your Password? or UserID? http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1176429871 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1176429871 Mon, 20 May 2013 08:51:17 +0000 How do I change my old password? Anaerobic Treatment Short classes http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369057705 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369057705 Mon, 20 May 2013 08:48:25 +0000 I'm looking for like a week long or less class on Anaerobic digesters.  I like in MS and all of the waste water classes are  for aerobic. I run a 35MG anaerobic digester and just want some extra training.   Thanks, Tucker Worm in anaerobic! http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369042158 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369042158 Mon, 20 May 2013 04:29:18 +0000 Hi all I `m operating a poultry wastewater plant (activated sludge). there are lots of worms in anaerobic basin by about 2-3 cm length and similar to earthworms. Are they good or bad? I don`t know what to do! Thanks for the help Regards Mina Alternative coagulant in water treatment http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369023665 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1369023665 Sun, 19 May 2013 23:21:05 +0000 In NZ, we mainly use Poly aluminium chloride as a coagulant in water treatment. Just wondering if any of you are aware of any alternative coagulant products which are not aluminium or other metal based? Dry Wells http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368952738 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368952738 Sun, 19 May 2013 03:38:58 +0000 i am trying to reason out why dampers should not be used on exhaust or fresh air ducts serving the dry wells? i look forward to your replies. Positive charge density test http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368927351 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368927351 Sat, 18 May 2013 20:35:51 +0000 Hi, Positive charge density is an important parameter of PAM, it relates to PAM cost and dewatering efficiency. I want to know how to test positive charge density? Regards Chen MLSS in Aeration tank!!!! http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368422438 Water and Wastewater.com Help Forums/Water & Wastewater Treatment Forum http://www.waterandwastewater.com/cgi-bin/yabb/YaBB.pl?num=1368422438 Fri, 17 May 2013 22:08:55 +0000 Hi You should give bit more detail about your process because it is not possible to give good advice according to the info you have given. For inlet you are talking about BOD but you limit is COD. what is your BOD. Check your nutrient levels, as has been commented on before. However I recommend you run according to sludge age and not F/M. The latter can be quite misleading if you have nonbiodegradable colloidal or solid organic matter in the influent. a microscopic analysis will also help you very much to find the correct sludge age.