Recent content by ch81pc

Can anyone recommend a good low maintenance on line DS meter for use in sewage sludges 0-10% typical range? Many thanks

Diquat is not a good idea as will remain active through your final effleunt and will get into the river and kill that too. Your duck weed will double roughly every 24 hours, so skimming will control but not eliminate your problem. If the weed is staying in the tank and not contaminating your...

We have used a live floor loading hopper taking 2x 30 tonne tippers at a time, which feeds into a twin covered auger. We do get some leaching from the belt, so be sure to have adequate draiange and wash down facilites. We dose quick lime into the twin augers and then pass into a plough shere...

Off gasing and airlocks can be a major problem, especially if your plant is in an area with warmer temperatures, in which case you may need to chill your hypo to reduce the gasing. Normally I would do everything I can to prevent negative suction pressure with hypo. Are you using diaphragm dosing...

We use ion exchange No sludge.

We operate on softened carrier water on plants up to 160 Mg/d. Scale will form at the point where hypo meets unsoftened water forming calcium or magnesium carbonates due to the pH of the hypo - If your total hardness is <40ppm you shouldbe able to use un softerned carrier water without too many...

I've used up to 100ppm, but that was in a known problem main with a history of quality issues. In 98% of cases there is no need to go above the 25ppm.

Approximation is 2 cubic feet per person per day. But depends on freshness of the sludge. It's a good starting point though.

Usually in the region 0.2mgl. If you don't have dilution water you need to approximate the polymer viscosity to that of the sludge to aid mixing. If your are dosing to raw water your batches should be in the around 0.05mgl

Medcalf and eddy is a good start

If circular clarifiers I use round road sweeper brushes sized to fit the channel. The bridge pulls them round. If you cut them in half to they can be sized to fit over the tops of the weirs and clean those too. Cheap and simple.

Does the wet well operate at a higher level in the wet weather? If so higher suction head solves the problem. Maybe your problem is suction head rather than delivery? You can modify the suction pipework to reduce head loss, trim impellers on a couple of pumps or fit car's to over come the issue.

3pg + I +e where p is population equivalent g is water use per head I is infiltration (ground water leaking into old sewers) and e is industrial input. Typical values for each can be found on the web. diurnal flow typically varies 1.5 to 1.8 times the value over the day. Night time 3 am being...

Honour oak works well on a 25% turnover each week. Might want to think about chloramination rather than super/de.

Without over engineering - 3 ft or 1 meter per second is the rule of thumb generally used.