Large pores and high turbidity capture capacity

In single-layer filtration using only filter sand, fine sand particles stratify in the upper layer. This results in turbidity
capture occurring primarily near the surface layer, known as surface filtration, leading to limited turbidity removal.
Anthracite has a lower density than filter sand and due to its characteristic of stratifying in the upper layer even at large particle sizes, can be combined with filter sand to achieve ideal [multi-layer filtration], significantly increasing turbidity capture. It is widely used in water treatment plants nationwide.

Furthermore, anthracite’s angular shape creates large voids and a high specific surface area. This allows for effective utilization of the entire filter bed in [deep bed filtration]. It is also used in [anthracite deep bed filtration], where a single layer forms a thick filter bed.

Using anthracite provides the following benefits due to these characteristics:
● Reduced waste water volume through extended filtration duration (improved water recovery rate)
● Accelerated filtration speed, enabling space-saving equipment
● Prevention of filtration blockage caused by diatoms (Synedra) and cyanobacteria (Microcystin)
● Prevention of mud ball formation on the surface layer of filter sand, etc.

Microflocs grow easily

The complex, angular shape of anthracite particles creates numerous diverse pores between them. Even when untreated water is fed into the filter bed without sufficient agitation after flocculant injection, it undergoes agitation as it passes through the anthracite’s diverse pores, enabling the formation of good microflocs. This contributes to improved treated water quality.
● Improved treated water quality

Easy modification from single-layer sand filtration ponds

The cleaning method for anthracite is identical to the process for filter sand. This means that when converting an existing single-layer filter sand tank to a dual-layer system incorporating anthracite, no new cleaning equipment is required. Simply removing part of the filter sand from the tank and replacing it with anthracite allows for an easy upgrade that improves filtration performance.
● Improved filtration performance at low cost

Excellent chemical resistance

High-quality anthracite contains few impurities and a high carbon content, making it insoluble in both acidic and alkaline water. This property allows it to be effectively used in chemical plants, such as soda ash manufacturers.
● Suitable for use with all types of chemical solutions

Can be used as a biological carrier

Anthracite possesses characteristics that make it highly susceptible to biofilm formation due to its high porosity and large surface area. This means it is not only ideal for physical filtration but also serves as an optimal carrier for biological treatment.
● Highly efficient biological carrier

Anthracite Quality Specifications

	Our products(1)	Our products(2)	Quality regulation (physical properties) (JWWA A 103-2:2006-2)
density	1.42g/cm3	1.46g/cm3	1.40～1.69g/cm3
Abrasion rate	0.9%	1.2%	≤3.0% less
Hydrochloric acid solubility	0.7%	0.8%	≤6.0% less

Anthracite Standard Product

Effective Size	0.7mm	0.8mm	1.0mm	1.2mm	1.5mm	2.0mm	2.5mm	3.0mm	4.0mm
Uniformity Coefficient	1.5 _or less, _or 1.4 _or less
Appearance	Granular
Raw Coal	Hong Gai Coal

We can also manufacture products with the specified effective size and uniformity coefficient upon request.
Please be aware that the effective size includes an error margin.

30 L PE bag, 1,000 L flexible container bag
*Pallet loading available upon request.

When placing your order, please specify the [Effective Size] _and [Uniformity Coefficient].

For the first time in Japan, Tohkemy products have received quality certification for all filter media (filter sand, anthracite, manganese sand, filter gravel) specified in theJWWA Standard “JWWA A103:2006-2” for water supply filter media.

●The quality of filter media is specified in the Ministry of Health and Welfare Ordinance and the Japan Water Works Association(JWWA) Standards.

●Previously, we have had business entities visit our factory
for inspections to verify quality. However, given the current labor shortages and the COVID-19 pandemic, we recommend JWWA-certified products that you can use with confidence without needing to verify them yourself.

●If your pipes and fittings are certified, make sure your filtration media—the heart of water purification—is certified too!

About Vietnam Hong Gai Coal

Main Properties of Hong Gai Anthracite

	Moisture(%)	Ash Content(%)	Volatile content (%)	Sulfur Content (%)	Fixed Carbon(%)	Calories（kcal/kg）
Hong Gai Coal	≤5	≤5～7	≤5～7	≤0.65	≥86	≥7,900～8,100