Ground & Surface Water Treatment

Improve the Production of Drinking Water withNatural and High Efficient Calcium Carbonate Products

Ground and Surface Water – Main Source of Drinking Water

Out of all the water on earth, salt water in oceans, seas

and saline groundwater make up about 97% of it. Only

2.5–2.75% is fresh water, including 1.75–2% frozen in

glaciers, ice and snow, 0.7–0.8% as fresh groundwater

and soil moisture, and less than 0.01% of it as surface

water in lakes, swamps and rivers. Fresh and unpolluted

water accounts for 0.003% of total water available

globally.

Fresh water is naturally occurring water on the earth‘s

surface in ice sheets, ice caps, glaciers, icebergs, bogs,

ponds, lakes, rivers and streams, and underground as

groundwater in aquifers and underground streams.

Fresh water can be defined as water with less than 500

parts per million (ppm) of dissolved salts.

Surface and ground water are two separate entities,

so they must be regarded as such. However, there

is an ever-increasing need for management of the

two as they are part of an interrelated system that is

paramount when the demand for water exceeds the

available supply.

Surface water is water on the surface of

the planet such as in a stream, river, lake,

wetland, or ocean. It can be contrasted

with groundwater and atmospheric water.

Non-saline surface water is replenished

by precipitation and by recruitment from

ground-water. It is lost through evaporation,

seepage into the ground where it becomes

ground-water.

As water runs off along the surface, it stirs

up and suspends particles of sand and soil,

creating silt in the surface water. In addition,

the streaming action erodes rocky surfaces,

producing more sand. As the surface water cascades over rocks, it is aerated. The combination of oxygen, inorganic

nutrients leached from the terrain, and sunlight supports a wide variety of life forms in the water, including algae,

fungi, bacteria, small crustaceans, and fish.

Surface Water

Water salinity based on dissolved salts

Fresh water Brackish water Saline water Brine

< 0.05% 0.05–3% 3–5% > 5%

Surface water and Groundwater characteristics

Characteristic Surface Water Ground Water

Turbidity high low

Dissolved minerals low-moderate high

Biological content high low

Temporal variability very high low

Other sources give higher upper salinity limits for fresh water, up to 3000 ppm.

Groundwater

Groundwater is the water located beneath the earth‘s

surface in soil pore spaces and in the fractures of

rock formations. A unit of rock or an unconsolidated

deposit is called an aquifer when it can yield a usable

quantity of water. Groundwater is recharged from,

and eventually flows to, the surface naturally; natural

discharge often occurs at springs and seeps, and can

form oases or wetlands. Groundwater is also often

withdrawn for agricultural, municipal, and industrial

use by constructing and operating extraction wells.

As groundwater encounters different minerals,

it dissolves them according to their solubility

characteristics. A good example is the reaction of

groundwater with limestone. Limestone is a mixture of

calcium and magnesium carbonate which is only slightly

soluble in neutral water. The acidic groundwater reacts

with basic limestone in a neutralization reaction that

forms a mixture of calcium and magnesium bicarbonate,

both which are quite soluble in water. Unfortunately,

the water can be very hard, due to the neutralization/

dissolution reactions described above.

Omya has over 40 years’ experience in the water

treatment market, mainly for pH control and soft

water hardening. Calcium carbonate granules

such as Filtracarb and Juraperle are used in the

remineralization filter bed process. These products

comply with international standards e.g. European

Standard EN 1018 for such uses. New developments

in products and application solutions expand Omya’s

existing know-how in water treatment using Calcium

Carbonate.

Omyaqua is a micronized Calcium Carbonate for pH

adjustment of acidic ground and surface water. Good

pH control is essential to stabilize the water and for

effective control of deposition and corrosion in many

water systems. Therefore, it is important to have a good

understanding of the meaning of pH and the factors

that affect it. Carbon dioxide, CO2, is usually present in

ground & surface water. CO2 reacts with the water to

form carbonic acid, H2CO3(1). When Omyaqua is added

to CO2-acidified water, it reacts and dissolves with the

carbonic acid to produce calcium hydrogen carbonate,

Ca(HCO3)2 (2). This chemical ability drives the treated

water towards the equilibrium pH and avoids major

shifts of pH in case of dosing troubles (buffering effect).

• (1) CO2 + H2O <---> H2CO3

• (2) H2CO3 + CaCO3 <---> Ca(HCO3)2

The three species carbonic acid, bicarbonate, and

carbonate can be converted from one to another by

means of changing the pH of the water. Variations in pH

are reduced through the „buffering“ effect provided by

the addition of Omyaqua with the consequence that

the pH of the system does not change as quickly as it

does in unbalanced water.

Consequently Omyaqua provides the required alkalinity

by its ability to neutralize the acidic (soft) ground

or surface water through the buffering mechanism

mentioned above.

Water Treatment Products & Solutions by Omya

Omyaqua for the buffered pH Control of Ground and Surface

Raw Water

Sludges

FlashMixer

Flocculator LamellaSeparator

ClearWell

Sand Filters

OmyaquapH djustment

Omyalime precipitation

Omyafloc flocculation

Treated Water

Ch

lori

nat

ion

M M

M

Omyalime precipitation

Omyafloc flocculation

©2014 Omya International AG | P.O. Box 335 | CH-4665 Oftringen | www.omya.com

Omya has taken every possible care to ensure that the information herein is correct in all aspects. However, Omya cannot be held responsible for any errors or omissions which may be found herein, nor will it accept responsibility for any use which may be of the information, the same having been given in good faith, but without legal responsibility. This information does not give rise to any warranties of any kind, expressed or implied, including fitness for purpose and non-infringement of intellectual property. The technical information presented comprises typical data and should not be taken as representing a specification. Omya reserves the right to change any of the data without notice.

Because of its chemical purity and quick dissolution

kinetics, our fine dispersed Omyalime is an optimal

product used for water and also waste water treatment

applications.

Drinking Water treatment normally requires different

physical and chemical treatment methods of the raw

water as this contains germs, bacteria, metal compounds

and is it too soft or too hard. In the drinking water

treatment process, the addition of lime may play an

important role. Omyalime can consequently be used

in 3 different drinking water treatment applications to

provide a stable and high quality of drinking water.

• Softening (decarbonization) – Precipitation of the

hardness components Calcium and Magnesium

• Hardness increase (remineralization) – Formation of

carbonate hardness using carbon dioxide and lime

• Neutralization – Adjustment of the pH-Value and

binding of free carbonic acid

•

In Europe most of the drinking water is made out of

ground- and surface water. In many regions such

groundwater is contaminated with higher levels of iron

and manganese. The public water supply made out of

ground water can therefore only be secured by using

the appropriate and functioning treatment processes

and whereas Omyalime is an excellent, natural and

sustainable product to precipitate and remove unwanted

water constituents such as iron and manganese.

Omyafloc™ is an inorganic flocculent which has

been developed due to the increasing demand in

environmental friendly „greener“ chemistry in water

and waste water treatment as well as to reduce the

negative environmental, health and safety implications

stemming from the extensive use of chemicals in this

industry. Omyafloc coagulants/flocculants have been

developed to provide a more sustainable and eco-

sensitive alternative to traditional polymer chemistry.

Omyafloc are highly efficient and cost-effective

inorganic coagulants/flocculants which are designed

for a wide variety of mainly mineral based liquid/

solid separation processes in water and waste water

treatment. Omyafloc facilitates the agglomeration

of destabilized particles into large size flocs which

can be effectively removed by sedimentation, or

mechanically assisted separation processes. Omyafloc

often provides superior efficiency in liquids/solids

separation processes without the use of conventional

coagulants, but where Omyafloc alone does not deliver

the specific performance required it may be co-fed with

a conventional coagulant.

Omyafloc can be used in the purification of surface

and ground water providing the following benefits:

• Improves environmental compliance

• Improves operational efficiency

• Improved equipment capacity

• Improved TSS (Turbidity) removal

• Minimizes sludge volume

• Enhanced TOC removal

• Improved color removal

• Non hazardous

Omyalime - The optimal Solution for Water and Wastewater Treatment

Omyafloc a New High Performance Environmental Friendly „Green“ Flocculent