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Energy Saving

Effects of Waterkeeper Addition to Waste Water Treatment Facility Based on the Activated Sludge Method and Its Energy Effect

By the addition of Waterkeeper (WK hereafter) to the aquatic environment, effective microorganisms and bacteria living only in the aerobic area but also in the anaerobic area can be activated. In the conventional activated sludge process, the decomposition of organic compounds is executed only by aerobic microorganisms and bacteria. The ecosystem in the activated sludge basin normally reduces to the distorted one much different from the natural ecosystem because of the selection caused by the struggle for existence of microorganisms and bacteria abnormally grown under the violent aeration. By the addition of WK, on the other hand, the decomposition of organic compounds is actively executed in the anaerobic region, suspended sludge particles and the sedimentary sludge layer in the thickening tank as well as in the aerobic region. That is, the decomposition of organic compounds can be taken place in the anaerobic region, suspended particles and the sedimentary sludge layer as well. Thereby, the decomposition of organic compounds executed in the aerobic region can be reduced. When WK is continuously added to the activated sludge basin, the artificial buildup of anaerobic region by rather slowing down the aeration operation, seems to be favorable for the realization of suppressed decomposition of organic compounds in the aerobic region.

The reduction of aeration operation implies the saving of electricity required for the aeration operation. Thus, the WK addition based on Waterkeeper Technology results in the realization of energy saving.

Summary:
1. Effects exerted on the aerobic region
Activation of effective microorganisms and bacteria
- Promotion of oxygen consumption
- Promoted decomposition of organic compounds
- Promoted formation of nitrate, sulfate and phosphate ions

Activation of sulfur oxidation bacteria, thiobacillus thiooxidans
- Promotion of hydrogen sulfide (H2S) consumption

Activation of nitrification bacteria
- Promotion of organic compound decomposition, ammonia (NH3) consumption and nitrate ion formation Activation of phosphorous (P) assimilation microorganism and bacteria
- Promotion of phosphate consumption
Deactivation of corruptive and miscellaneous bacteria
- Decrease in oxygen consumption

2. Effects exerted on the region where DO≒0
Activation of denitrification bacteria
- Promotion of nitrate consumption, nitrogen gas formation, but no DO consumption  

3. Effects exerted on the anaerobic region
Activation of effective microorganisms and bacteria → no DO consumption
Activation of organics partial decomposition bacteria
- Promotion of partial decomposition of organic compounds
- Promoted formation of carbon dioxide (CO2), methane (CH4), NH3 and H2S

Activation of phototrophic bacteria:
Activation of green sulfur and purple sulfur bacteria
- Promotion of photosynthesis
- Promotion of H2S consumption (as the electron donor)

Activation of purple non-sulfur bacteria
- Promotion of photosynthesis
- Promoted consumption of organic compounds (as the electron donor)

In the activated sludge process, however, there exists no anaerobic area because of the vigorous agitation in the aeration basin, and accordingly, the above-mentioned effects exerted on the anaerobic region, cannot be expected by WK addition into the aeration basin. It is rather recommended under the continuous addition of WK that the anaerobic region should artificially be incorporated into the aeration basin by suppressing the aeration operation.

The anaerobic condition, however, can be kept inside the suspended solid particle-like sludge (MLSS), and accordingly, the similar effect can be expected to that exerted on the sedimentary sludge layer (located in the thickening tank) as mentioned below.

4. Effects exerted on the sedimentary sludge layer (located on the bottom of thickening tank)
Activation of effective microorganisms and bacteria → no DO consumption
Activation of anaerobic organics partial oxidation bacteria
- Promotion of partial decomposition of organic compounds
- Promoted formation of CO2, CH4, NH3 and H2S

Practical Application Results:
・Sewage treatment facility
- About 50 percents of energy (electricity) saving can be realized.
・Industrial waste water treatment facility
- About 30 percents of energy (electricity) saving can be realized
.

Energy Saving Effect Accompanied by the Continuous Addition of Waterkeeper to Waste Water Treatment Facility Based on the Activated Sludge Method.

Conventional waste water treatment facility based the activated sludge method

Aeration Basin (under the aerobic condition)
In the conventional activated sludge process, the decomposition of organic compounds is allotted only by microorganisms and bacteria living in the aeration basin where the aerobic condition prevails. The ecosystem there is normally changed to the distorted one much different from the natural ecosystem because of the selection caused by the struggle for existence of microorganisms and bacteria abnormally grown under the violent aeration. The operation of aeration essentially has no selectivity that effective microorganisms are activated, whereas bacteria leading to the putrefaction and contamination are deactivated. Thereby, the aeration operation activates both effective and non-effective microorganisms and bacteria equally. Or rather, a certain kinds of effective microorganisms and bacteria are possibly selected because of struggle for existence (leading to the buildup of distorted ecosystem). Accordingly, sufficient decomposition of organic compounds cannot be realized in spite of enormous energy input. Besides, corpses of microorganisms build up the sludge. In order to keep high dissolved oxygen concentration, the energy input, i.e., the electricity required for the aeration operation is increased. Since the aerobic condition prevails in the aeration basin, nitrate cannot be converted to nitrogen gas because of inactive denitrification bacteria.

Thickening Tank (under the anaerobic condition)
In the effluent from the aeration basin (which is transferred to the thickening tank), undecomposed organic compounds, corpses of microorganisms and so on, which are normally called sludge, are contained. Through the settling of solid-like substances, the sedimentary sludge layer is formed. The environment in the thickening tank, is not suitable for effective microorganisms and bacteria, and accordingly, they are in a low activity state. Phototrophic bacteria such as green sulfur and purple sulfur bacteria are also in a low activity state because of the high turbidity there.

In summary, in both aerobic and anaerobic regions, i.e., in both the aeration basin and the thickening tank, the activation of sound microorganisms and bacteria like those in the natural ecosystem, hardly occurs.

Waste water treatment facility modified by the addition of Waterkeeper (WK)

Aeration basin
The aeration can be reduced and shortened because of the synergetic effect caused by the addition of WK;
・Activation of effective microorganisms → Promotion of dissolved oxygen (DO) consumption

・Promotion of decomposition of organic compounds
- Promoted formation of nitrate, sulfate and phosphate ions

・Activation of sulfur oxidation bacteria, thiobaccillus thiooxidans
- Promotion of hydrogen sulfide (H2S) consumption

・Activation of nitrification bacteria
- Promotion of decomposition of organic compounds
- Promotion of ammonia consumption and nitrate formation

・Activation of phosphorous (P) assimilation microorganisms and bacteria
- Promotion of phosphate consumption

・Deactivation of corruptive and miscellaneous bacteria (bacteria leading to putrefaction and
contamination) → Decrease in DO consumption

Effects exerted on the region where DO≒0
・Activation of denitrification bacteria
- Promotion of nitrate consumption and nitrogen gas formation

・Reduced and shortened aeration operation
- Saving of energy, i.e., electricity required for the aeration operation

Thickening Tank (under the anaerobic condition)
・Activation of organics partial decomposition bacteria
- Promotion of partial decomposition of organic compounds
- Reduction and shortening of aeration operation

Extended effect of WK addition:
・Activation of effective microorganisms and bacteria, but no DO consumption

・Activation of organics partial decomposition bacteria
- Promotion of partial decomposition of organic compounds
- Promoted formation of carbon dioxide (CO2), methane (CH4), ammonia (NH3) and hydrogen sulfide (H2S)

Activation of phototrophic bacteria:
・Activation of green sulfur and purple sulfur bacteria
- Promotion of photosynthesis
- Promotion of H2S consumption (as the electron donor)

・Activation of non-purple sulfur bacteria
- Promotion of photosynthesis
- Promoted consumption of organic compounds (as the electron donor)

In the sedimentary sludge layer located on the bottom of thickening tank
・Activation of effective microorganisms and bacteria, but no DO consumption

・Activation of anaerobic bacteria leading to partial decomposition of organic compounds
- Promoted partial decomposition of organic compounds
- Promoted formation of CO2, CH4, NH3 and H2S