Waste water tratment plants
The importance of sand filtration in wastewater treatment
Overview
Sand filtration is an effective wastewater treatment step for your wastewater treatment system. Why? Discover it below!
Why use sand filtration in wastewater treatment?
The key features of the sand filtration wastewater treatment?
Sand polishing filters can be used for tertiary treatment when placed after a wastewater treatment plant. They can also be used as a secondary treatment when placed after a septic tank.
The tertiary treated effluent has been treated to a high enough standard following the overriding principles of the EPA Code of Practice that it may be discharged to groundwater.
The tertiary sand polishing filter will require discharge to a tertiary infiltration area designed and sized in accordance with Option 6 in Table 10.1. They are made up with stratified layers of sand (fine and coarse) and gravel. These layers remove the thinnest particles that can still be present in the effluent after secondary treatment.
Sand polishing filters must be compliant with the EPA Code of Practice. Tricel solution, the Tricel Sandcel has many advantages such as:
- A small footprint
- Easy to install
- Made in GRP impermeable panels, a resistant and waterproof material that avoid any leak
- High treatment quality as the final effluent quality of <1 mg/ltr BODs.
What is sand filtration wastewater treatment?
What is the tertiary treatment system?
A tertiary treatment system may be used when primary and secondary treatments are insufficient, for example, when discharging water to surface waters or reducing nutrients and pathogens in sensitive areas.
A tertiary treatment system can consist of sand filters, constructed wetlands, and packaged media filters, the same kinds of systems used for a secondary treatment, or be more specialised systems for disinfection or nitrogen removal.
Prefabricated tertiary treatment systems must comply with EN 12566 Part 7 as applicable, and should be certified. In Ireland, it must also be certified to SR66.
Focus on sand filtration wastewater treatment
A tertiary treatment system may be used when primary and secondary treatments are insufficient, for example, when discharging water to surface waters or reducing nutrients and pathogens in sensitive areas.
A tertiary treatment system can consist of sand filters, constructed wetlands, and packaged media filters, the same kinds of systems used for a secondary treatment, or be more specialised systems for disinfection or nitrogen removal.
Prefabricated tertiary treatment systems must comply with EN 12566 Part 7 as applicable, and should be certified. In Ireland, it must also be certified to SR66.
According to EPA Code of Practice, sand filters may be employed for tertiary treatment. These tertiary sand polishing filters can be monograde (single-layer) or stratified and must be at least 900 mm thick.
The hydraulic load must not exceed 60 l/m2 .d and the sandshine filter can be covered with topsoil and grassed to a maximum depth of 300 mm. In a typical stratified filter layout, three layers of sand, consisting of coarse sand in the top layer and fine sand in the middle and bottom layers, are separated by thin layers of washed pea gravel or crushed stone. Access to regular visual inspection of media should be guaranteed.
Regarding the monograde filter, please see below the criteria for sand grades suitable for sand polishing filter layers, according to the Environmental Protection Agency.
| Design factor | Design criteria |
|---|---|
| Pre-treatment | Minimum of secondary treatment |
| Top coarse sand layer | Effective size (D10) 0.25–0.75 mm; D60/D10 (Cu ) < 4 |
| Fine sand layers | Effective size (D10) 0.15–0.25 mm; D60/D10 (Cu ) < 4 |
Regarding sizing the area required for the Tertiary infiltration area underneath the sand polishing filter, please find below Table 10.1 referring to option 6 : according to the EPA Code of Practice 2021.
Which sand filtration wastewater treatment to choose?
Tricel Sandcel Wastewater Treatment
Sand polishing filters provide a dual function of polishing the effluent from a wastewater treatment system and disposing of the treated liquid into groundwater.
The Tricel sand filtration treatment system can be installed at varying heights on the site to suit all conditions, including under or overground.
Tricel offers Sandcel, which is an effective and high-quality sand polishing filter.
Tricel Sandcel provides you with an additional solution for your wastewater treatment process.
Tricel Sandcel is composed of certified sand and pea gravel layers according to the EPA Code of Practice. Our product is made with GRP panels, following the EPA Code of Practice, which ensures a resistant and effective tertiary treatment over the years.
Tricel Sandcel offers you quality treatment of your wastewater and many advantages as well.
A Tricel Sandcel wastewater system means:
- high performance
- a flexible design
- a small area required
- a system quick to install
- an aesthetic finish for your garden
- an impermeable and not deteriorating structure
Please look at our page to learn more about the Tricel Sandcel.
What do Tricel offer?
Both our sand polishing filter (Sandcel) and our packaged filter system (Puraflo) are performant. Depending on your project and the type of ground you have, one must be recommended to you over the other one. Both will provide Tertiary treatment to treat the effluent to a higher quality before discharging into a tertiary infiltration area
What is the difference between both?
Sand polishing filter as Tricel Sandcel is composed of sand and pea gravel. This system uses sand technology to remove the effluent’s dissolved particles. It is usually recommended for smaller sites with restricted areas.
A packaged filter system such as Tricel Puraflo is composed of coconut fibre. The packaged filter system collects the effluent from the septic tank or the wastewater treatment plant via a pump. The pumped effluent filters through the coco fibre media, which treats the effluent. The process combines biological, chemical and physical processes that remove high-level pathogens and nutrients.
The packaged filter system is usually recommended for environmentally sensitive sites that require a high level of treatment, i.e. water table protection areas.
Get in touch
HQ
Tricel (Killarney) Unlimited Company
Ballyspillane Industrial Estate, Killarney, Co. Kerry, V93 PN84, Ireland
Tel: 00353 (0)64 6632421