WASTEWATER PRE-TREATMENT

 

Separation of grit, grease and waste

Compact unit type EPM is designed to extract waste materials, sand and grease from wastewater for smaller capacities.

It is particularly suitable for pre-treatment of wastewater from septic tanks before get on the city's sewer system.

The waste water is pumped from the tanks or assembly shaft in roto screen (2) having a slot in the drum s = 2, 3 mm.

The water is filtered through the drum and transferred to the bowl (4).

Scrap isolated on a rotating drum is removed with a remover and go to the spiral compactor (3), where the waste material is washed, drained, pressed and cast out into the container.

Water with sand and fats are retained in the vessel with two chambers next 5-6 min.

Retaining and mixing there are the following effects:

- Separation of the sand in the conical section of the container is more than 95% of the grains of size more than 0.2 mm,

- Separation of the free fat is more than 75% of the fat in the chamber, from where it is vented via a valve from time to time in the barrel of the fat (6).

-Water free of sand and fat goes on to further treatment, and the sand is transported by screw conveyor (5) in the container for sand.

The efficiency of extraction of fat may increase using one of the following options:

b) Installing of aerator mixer below the inlet chamber pots and blowing air,

c) Installing aerators in the inlet chamber and blowing air without mixer

d) Installing of special mixers which draws air and floated mixing zone

Compact unit type ECSE

For larger capacities or when available space requires, compact unit can perform in a variant type ECSE

1-chamber, 2-roto screen, 3- compactor, 4.1-bowl, 4.2-aerator, 4.3-screw transporter, 4.4-scraper for fat, 5-screw transporter, 6-container

Q (m3/h) - Flow
V (m3) - Volume
t (min) - Time
Y(m/h) - Surface load
v (m/sec) - Speed
P (m2) - Surface area
B (m) - Width
L (m) - Lenght

The equipment is made of high quality materials: AISI 304, 316, 316L, 316Ti

 

SAND TRAP and GREASE TRAP

For separating sand and grease from municipal wastewater in use are longitudinal aerated sand traps as a concrete structure.
Sizing of elements of construction of the facility will be done according to the design criteria in the table attached.

For separating sand and grease from municipal wastewater for larger settlements are used longitudinal aerated sand traps in the concrete implementation.
Sizing of elements of construction of the facility will be done according to the project criteria in the table attached.
Depending on the capacity of the waste water and space requirements shoud be adopted sand trap with one or two chambers.
The most commonly adopted sand trap for higher capacities is with two chambers in version A or B.
There is solution for longitudinal accumulation or for suction of sand.
For the sand trap with longitudinal accumulation, sand precipitated in the channel lays in the sand pit, and by air pump (mammoth pump) or by submerged centrifugal pump, sand is tranfered to the claser for purpose of washing and dehydration.
For the suction sand, pump is installed on the bridge. Suction of mixed sand and water from the channel going to collecting chanel.
Collecting chanel could be made of steel or concrete and it is set over the entire length of the pool. The mixture of sand and water from the canal by gravity or pump drains to claser.

In order to achieve efficient separation of fat and sand from waste water, it is mandatory to blow the along the pool, which causes a circular movement of water and thus stimulates fat separation, but also maintains the organic materia in the water.

Separated grease finding its way to chamber for fats.

Materials:
Material for equipment above water: carbon steel or zinc-coated.

The material in contact with water: AISI 304 or on request.

 

LONGITUDINAL AERATED SAND TRAPS

 

Equipment for longitudinal aerated sand trap

 

Suction sand traps