Advantages of Conical Tanks for Effluent & Sludge over flat bottom storage tanks for wastewater treatment often start with the ability to fully drain the tank which makes washing and decanting easier. When setting up storage tanks for wastewater storage there are often constraints on budgets which can sometimes result in a flat base tank being selected over the more expensive conical tank.
Conical Tank has many advantages over flat base tanks for effluent and sludge storage in the storage of primary treatment wastewater. The conical tanks advantages are also seen later in the processes where cleaner water may still have particles that need settling out. Bellow, we compare both options and explain how to make this decision right the first time. A cone bottom storage tank is a round cylinder structure with a conical base allowing a full drain of the contents. There is a choice of different sloped cones for different applications such as sludge, however, in settlement & clarification, a steep cone is required for processes they are used for. More details here.
| Tank Type | Pros | Cons |
| Cone Bottom Tanks | 1) Sloped base = 100% drainage
2) Easy to bottom drain sludge 3) Can be used for settlement applications. |
1) Extra cost. Must purchase a stand and hardware.
2) Not as easy to move. |
| Flat Bottom Tanks | 1) Quick to install.
2) Can be moved easily. 3) Less cost (no stand needed) |
1) Some liquid will stay in the tank and not drain.
2) Build-up of sediment in the tank over time |
| Range of Capacities Available | 50 Litre – 30,000 Litres | |
Cone-bottom tanks are used in wastewater applications where 100% drainage of the tank is required and to reduce sludge from exiting the tank to processes downstream. Dewatering is the further reduction of the sludge amount after the thickening as the liquid still must be dewatered to a dry and porous form. Dewatering is generally by machine processes using a filter press and centrifuge to treat wastewater. Enduramaxx works with many industrial wastewater treatment companies who offer advice on wastewater and sludge treatment processes covering coagulation, chemical treatment flocculation, biological treatment, sludge digestion, sludge drying, pH control and dewatering.
Sludge treatment is necessary to reduce and ameliorate the sludges produced within the biological wastewater treatment. Sludge generally has fewer dried solids in it than it looks like it has as a typical DAF plant sludge will be approximately 5% solid or 95% water equating to 19 tonnes of water and 1 tonne of solids from a 20-tonne load of sludge. By thickening the sludge there is a lot of potential for costs savings on the plant as sludge can be expensive to dispose of and is priced by volume.
Sludge thickening is the treatment the sludge undergoes and is possible to reach a volume reduction of up to 80% by thickening before further treatment is required in the wastewater treatment system. This is where wastewater treatment
Sludge Tank Decant Valves, BSP or flanged for sludge tanks, racking, decanting. For draining off liquid from sludge in tanks. Over time sludge settles and the water on top can be drained off.
The slope of the cone tank impacts the efficiency at which stored liquids can exit the tank and the efficiency at which the materials stored will settle in the tank. Heavy liquids and sludge require a steeper tank slope design to facilitate settling when in a silent or clarification tank, however for bulk storage sludge tanks a shallow 5- or 15-degree cone will suffice. View our full range of conical tanks here.
Enduramaxx manufacture tanks for effluent & sludge storage from either Polypropylene or High-Density Polyethylene which is selected to suit your specific application. Sludge is a thick, soft mud or other viscous liquids that is typically the by-product of wastewater treatment, industrial wastewater solids and settled suspension from potable water treatment. It often contains various types of pathogens as well as heavy contaminants, in the case of industrial waste, chemical pollutants. Sludge contaminated by chemical pollutants or heavy metals, demands complex treatment with these tanks having a number of applications on small sewage treatment plants, the concentration of food and agricultural waste for anaerobic digestion, and concentration of apple mulch after cider fermentation in the drinks industry.
For more information about cone-bottom settlement tanks, please refer to the contact us, email us at sales@enduramaxx.co.uk to speak to an Enduramaxx storage tank specialist. Follow Enduramaxx on Linkedin here.
