Primary (mechanical) treatment
For the treatment of sanitary wastewater from:
- Barracks, etc.
Available are compact plants capacity of 1,000-10,000 ES.
The plant is integrated mechanical and biological treatment and was added as needed to tertiary treatment.
|Effluent parameters||Average (mg/lit)||Maximum (mg/lit)|
Depending on the requirements, building requirements requires the recipient, maintenance and other possible choice of treatment, one of the technologies is available:
- elimination of organic pollution and the simultaneous stabilization of sludge
- elimination of organic pollution, nitrification, de nitrification and simultaneous stabilization of sludge and
- SBR technology
The choice of technology should always be left to a specialist who evaluates all conditions including the construction and cost of construction, the complexity of handling and maintenance.
Optimum running of the process, the plant operates without unpleasant smell.
Plant could be: buried, partly buried or surface and in that respect, plant can be easily fit into any environment.
Lamella or rotary piston compressor with protective hood will provide work without noise.
Fine bubble aeration with one of the type of diffusers (piston, plate or panel) will guarantees high efficiency aeration.
Installing modern equipment measuring and control process can be automated in the desired extent, lead and maintain the optimal mode.
Device-handling equipment by trained personnel is simple.
Our staff is always available for expert advice.
For capacities up to 10,000 ES typical mechanical treatment includes:
- Elimination of major material on an automatic screen or channel sieve
- Elimination of sand on sand trap type of “pista”
Lifting of water is done:
- Screw pumps (capacity above than 20 l / sec) or
- Centrifugal pumps
If you raise the water by submersible pumps, upstream is necessary to install automatic screen, a space about 20 mm, while the raises water by screw pumps require to install automatic screen behind the pump.
Material extracted on a grid at the plant to 10,000 ES generally immediately inserted into the container. A possible solution is previous pressing of material.
Sand extraction takes place in sand trap type of PISTA. Sand is evacuated by vacuum pump into:
- concrete chamber next to sand trap
- silos for sand or
- in classier
Surface water always returns to sand trap.
After primary treatment water goes to the secondary, biological treatment usually by gravity.
SECONDARY (BIOLOGICAL) TREATMENT
For the biological treatment is possible to choose one of the technologies:
- SBR process
- Process for removing carbon, nitrogen and phosphorous compounds and the simultaneous stabilization of sludge or
- Process for removing organic (carbon) compounds with nitrification and sludge stabilization
The choice of technology is not a simple question. Only an experienced specialist on investor requirements, conditions of construction and exploitation, and comparative analysis can suggest the optimum solution.
For the purposes of the case and requires recipient, after the biological tertiary treatment could be added.
Tertiary treatment including filtration on sand filters, the elimination of phosphorus chemical treatment and disinfection.
Disinfection could be performed by:
- Dosage sodium hypochlorite
- Chlorination by chlorine gas or
- UV disinfection
UV disinfection is superior by technical terms, but limited by cost of construction and maintenance cost.
For capacities up to 1,000 ES surplus stabilized sludge is dumped in a silo-pool for the excess sludge with occasional treatment of decantation. Thickened sludge has up to 5% dry solids.
Surface water always takes the beginning of the process. Sludge is treated from time to time on the following:
- transport to the nearest waste water treatment plant or
- dispose to dry on the field for further dehydration
Dehydration of sludge to 20-30% dry solids can be performed on the belt or centrifugal press. Because of the cost of building this procedure applies only in the capacity above the 5000 ES.
Equipment for the treatment of stabilized and thickened sludge is:
- screw pumps for handling sludge
- thickener for sludge with mixing
- equipment for preparation and dosage of polyelectrolyte
- decanter (centrifuge or belt)
- screw or belt conveyors for transport of sludge cake
- measuring and control equipment
Common practice for the plant capacity of 10,000 EC is that such plant to build a mechanical treatment unit, and for secondary treatment two parallel units. This is especially meaningful for tourist spots, which during the season have increased capacity.
Phase construction of the secondary, biological treatment, is practical and take place with the aim of accelerating the development of a simple capacity.