In the operation of power plants - be it PLTU, PLTG, PLTGU, or PLTA - the role ofchemical treatment is crucial to maintain efficiency, equipment life, and environmental compliance. This article descriptively explains the various power plant chemical solutions, their respective functions, and their benefits to system performance.
1. Raw Water Treatment (Pretreatment)
Raw water is the primary source for cooling systems and boilers. The pretreatment stage aims to remove dirt, sludge, and ions that cause scale and corrosion.
Chemicals used include:
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Coagulants and flocculants such as PAC and polymers to settle suspended solids.
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Phosphonate-basedRO antiscalants to prevent membrane scaling.
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Biocide such as isothiazolinone and sodium hypochlorite to inhibit the growth of microorganisms.
By controlling parameters such as turbidity < 1 NTU and SDI < 5, the RO system can work optimally and the membrane life becomes longer.
2. RO System and EDI: Maintaining Demineralized Water Quality
At this stage, chemicals are used to prevent scaling and biofouling on the RO membranes.
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Antiscalants and dispersants prevent scale formation.
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CIP chemicals (acidic & alkaline) remove foulants from the membrane surface.
High quality RO produced water maintains conductivity < 10 µS/cm and reduces the risk of turbine damage due to ionic contaminants.
3. Boiler and Steam Cycle Protection
One of the most critical points in a plant is the boiler. Scale, corrosion, and carryover can reduce steam generation efficiency.
Chemical solutions applied include:
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Oxygen scavenger such as sodium sulfite or carbohydrazide to remove dissolved oxygen.
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Phosphate treatment (TSP, DSP) to control alkalinity and prevent scaling.
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Volatile amines (morpholine, cyclohexylamine) maintain the pH of the condensate so that it is not corrosive.
With a pH setting of 9-11 and O₂ < 7 ppb, the system remains stable and corrosion-free.
4. Cooling Tower: The Key to Cooling Efficiency
Cooling systems require a combination of chemicals to prevent scaling, corrosion, and algae growth.
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Antiscalants and dispersants (HEDP, ATMP) prevent calcium scale.
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Corrosion inhibitors (molybdate, azole) protect metals from oxidation.
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Oxidative and non-oxidative biocides keep cooling water clean.
Controlling ORP 650-750 mV and pH 7-8.5 ensures heat exchange efficiency remains high.
5. Wastewater Treatment (WWTP)
Effluent water from the generating system needs to be treated to meet environmental quality standards.
Chemical solutions include:
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Coagulants/flocculants to settle solids.
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pH neutralizers using NaOH or H₂SO₄.
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Defoamer and odor control to keep the biological process stable.
With regulatory TSS and COD control, the power plant remains environmentally friendly.
6. Fuel Additives and Emission Control
For coal or oil-based plants, chemicals are also used on the combustion side:
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Fuel additives reduce slagging and fouling in the furnace.
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FGD sorbents (lime, NaHCO₃) bind SO₂ gas.
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Activated carbon (PAC) captures mercury emissions.
As a result, combustion efficiency increases and harmful emissions decrease significantly.
7. Support Programs: Cleaning, Passivation, and Defoamer
In addition to the main process, the plant also uses additional chemicals such as:
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Silicone defoamers to treat foam.
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Chemical cleaning for condenser and heat exchanger pipes.
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Passivation protects new metal surfaces from initial corrosion.
Conclusion
The use of power plant chemical solutions is not only to keep the system clean, but also to improve energy efficiency, extend equipment life, and maintain environmental compliance.
Each type of plant - PLTU, PLTG, PLTGU, and PLTA - requires a different combination of chemicals according to operating pressure, water quality, and fuel type. With the right chemical selection, the generation system will be more reliable, cost-effective and sustainable.
