Power | Industries

In thermal power plants, steam generated in the boiler is sent to the turbine to generate electricity, and the steam used for power generation is returned to water in the condenser and then fed back to the boiler. Water treatment in boilers and condensers is essential because impurities in the boiler feedwater can cause scale to adhere to boilers and turbines. Oxygenated treatment (OT) is also performed on boilers at thermal power plants to reduce the frequency of cleaning, thus making it more difficult for scale to adhere. Therefore, while OT-applied boilers have the advantage of not having to be cleaned for a long period of time, adhered scale is difficult to dissolve with chemicals and difficult to remove.

The chemical cleaning service for OT-applied boilers at thermal power plants first analyzes the composition of scale and conducts dissolution tests and then selects chemicals that are highly effective in cleaning persistent and insoluble scale. Then, sludge removal equipment, such as sludge catchers and filters, are installed in the boiler cleaning system to clean the scale using selected chemicals and prevent the sludge generated from returning to the boiler, ensuring to remove sludge. In addition to contributing to the stable supply of electricity by realizing stable boiler operation, the system also contributes to water conservation by reducing the amount of cleaning water used compared to conventional chemical cleaning.

Biogas is a methane-based gas produced by the fermentation of organic matter in industrial and general waste through the power of microorganisms. In wet methane fermentation, one of the methods of biogas generation, where raw materials with high water content, is when digestion liquid containing high concentrations of nitrogen compounds is generated when methane gas is produced. The nitrification-denitrification method commonly used to treat wastewater from this digestion liquid is a two-step process. The nitrification process carries out oxidation from ammonia to nitrous acid and then to nitric acid. The second step is denitrification process to reduce nitric acid to nitrogen gas. The nitrification process requires a lot of aeration power to activate bacterial activity, and the denitrification process requires a denitrification carbon source (such as methanol), so the growth of bacteria also creates excess sludge.

In wastewater treatment of digestion liquid, the introduction of a process utilizing ANAMMOX bacteria can s ignificantly reduce the amount of energy used for aeration, the amount of methanol and other substances injected, and the amount of sludge generated compared to the general nitrification-denitrification method. In addition, the overall installation space of the equipment can be significantly reduced due to the smaller capacity of the water tank required for the treatment. This process can be applied to a wide range of fields, including digestion liquid discharged from methane fermentation, semiconductors, urban sewage, and livestock production.

At geothermal power plants, steam generated deep underground is extracted to rotate turbines and generate electricity. Hot water is extracted along with the steam, and the conditions of the hot water, such as water temperature and pH, can cause corrosion and scale damage to the underground piping and aboveground equipment. This damage can result in deterioration of stable operation and power generation efficiency, so power generation facilities must be periodically shut down for cleaning and maintenance.

The Kurita Group identifies the substances that cause this damage and selects and applies appropriate water treatment chemicals to prevent corrosion and scale. This contributes to stable operations and improves the efficiency of power generation by reducing the downtime of power generation facilities. This contributes to higher productivity.

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