We will introduce an example of iron removal　and manganese removal treatment in groundwater using our filter material.
In order to use the groundwater in Osaka Prefecture as drinking water, iron, manganese,　and chromaticity that exceed the tap water quality standards are removed by iron removal　and manganese removal towers.

● Raw water quality

item	unit	Numerical value	Tap water standard
Water species	–	Groundwater	–
place	–	Osaka prefecture	–
pH	–	7.2	5.8～8.6
iron	mg/L	1.0	0.3　or less

item	unit	Numerical value	Tap water standard
manganese	mg/L	0.24	0.05　or less
Turbidity	degree	1.3	2　or less
Saturation	degree	12	5以下
TOC	mg/L	Less than 0.5	3　or less

Iron in raw water is 1.0 mg / L　and manganese is 0.24 mg / L, which are higher than the tap water quality standard. The raw water also contains chromaticity, but the TOC of the raw water is low,　and the results of prior tests have revealed that it was colloidal iron hydroxide, so a flocculant was injected. It can be judged that the chromaticity can be removed to 5 degrees or less by performing physical filtration.
We examined the treatment method so that the target values of treated water were iron: 0.3 mg / L or less　and manganese: 0.05 mg / L or less,　and delivered the equipment for iron removal　and manganese removal towers.

The filter medium to be filled in the filter tower has a relatively small load on the filter medium because both iron　and manganese have low concentrations, but since a flocculant is injected, anthracite e.s 0.7 mm　and manganese-free filter medium ferro It was done with multiple layers of Light MC3. In addition, the main purpose of backwashing the filter is to discharge the turbidity accumulated in the filter tower, but when using a coagulant such as PAC, the purpose is also to loosen the filter material, so one day. It is once.

item	Iron removal / manganese removal tower
Filter	φ2000mm×SH1830mm
Filtration material filling amount (per tower)	Anthracite e.s0.7mm:1.0m3　FerroliteMC3:2.2m3
Filtration rate	LV12.7m/hr
Chemical injection amount	NaClO: Inject free chlorine into treated water so that 0.5 mg / L is detected. PAC: 5 mg / L injection at the inlet of the filtration tower
Backwash process	Backwash: LV 30m / hr x 10min Stand still: 3 minutes Filtration drainage: LV 19m / hr x 10min
Backwash frequency	Once a day

As a result of delivering the above iron　and manganese removal equipment, we were able to obtain extremely clear water as shown in the table below　and in the photo by removing iron　and manganese.
The chromaticity was also reduced to 1 degree by removing iron. In addition, the turbidity of the raw water was already below the tap water quality standard, but it could be removed to less than 0.2 degrees,　and it can be said that very good water was obtained.

item	unit	Filtration tower entrance	Filtration tower exit
pH	–	7.2	7.3
iron	mg/L	1.0	Less than 0.01
manganese	mg/L	0.24	0.01

item	unit	Filtration tower entrance	Filtration tower exit
Turbidity	degree	1.3	Less than 0.2
Saturation	degree	12	1
Free chlorine	mg/L	1.0	0.6