Diversified options for water treatment
Diversified options for water treatmentAs long as the steam cycle dominates the power production industry, the choice of water treatment process is crucial to the successful operation of the power pla...
Diversified options for water treatment
As long as the steam cycle dominates the power production industry, the choice of water treatment process is crucial to the successful operation of the power plant. To ensure the safe operation of boilers and steam turbines, power plant managers are required to strictly control problems such as corrosion, scaling, fouling, salt accumulation, etc.
However, due to some difficult requirements, it is more difficult to design an excellent water treatment scheme than before. Management has restricted the choice of chemicals and demanded a reduction in wastewater emissions; environmentalists have called for a reduction in the consumption of water resources; and, in addition to deteriorating water quality at raw water points, directors and shareholders of the power sector have also demanded a reduction in operating costs for their own benefit.
It is gratifying that new technologies can be used to meet these challenges, such:
· RO (Reverse Osmosis) and EDI (Electrodeionization) make the boiler water supply treatment reduce the storage and treatment of chemicals.
Oxygen treatment enables the boiler to prevent corrosion and salt accumulation without sewage discharge.
The improved shutdown protection process increases the flexibility of operation and reduces corrosion.
All these advanced technologies are relatively easy to obtain due to the provision of agents and water treatment professionals everywhere. Agents try to assign tasks and even autonomy to those in key positions (at least in theory) to optimize the design of water treatment solutions-because these companies have specialized talents and resources.
It should be noted that although the agents have maintained a short-term track service record for some power plants, the power plant managers are still not convinced of these benefits. Similarly, auditors are still hovering outside these emerging advanced technologies in the field of water treatment.
No matter what level of agency or technology an enterprise is provided, 1 thing is clear: a successful water treatment process requires sufficient attention to every detail as before.
Reduce the use of chemical regeneration agents
In the past ten years, electrodeionization (EDI) has been one of the two major advances in industrial water treatment technology. The reason is that power plants now produce pure water without the costs, space, and space caused by the use of chemical recycled agents. Safety and environmental protection issues.
The commercial operation of EDI has actually been more than ten years old, but according to Robert K Glegg, the founder and president of Glegg Water Treatment Company, the early systems can only operate at low flow rates, and there are still reliability issues. Today's EDI system has been able to meet the requirements of various flow rates and water purity in power plants, and its operation is reliable. This is largely because EDI has been combined with another important technology in the field of water treatment-reverse osmosis (RO).
Before RO and EDI were applied, the traditional production process of boiler feed water was an ion exchange device regenerated chemically. After pretreatment, the pump force is used to make the make-up water pass through several stages of desalination (usually positive bed, negative bed and mixed bed). In these stages, impurities are removed through the ion exchange process.
Because the resin bed must be regenerated frequently, it is necessary to store and treat chemical regenerated agents such as acid and alkali.
By the early 1980s, the idea of reducing the use of chemicals led to the industrial application of RO. During the operation of RO, the make-up water is pressurized to overcome the two types separated by the semi-permeable membrane.
The osmotic pressure generated by different concentrations of solutions, when the reverse pressure applied is sufficient, the water will move in the opposite direction, that is, from the thinner side to the higher concentration side, thereby producing pure water and leaving waste salt liquid on the concentrated side.
In order to meet the requirements of boiler make-up water quality, the outlet water of RO should be further desalted. By the 1980s, this process was completed through a mixed bed ion exchange device. In any case, this process reduces the consumption of chemical regeneration agents accordingly. With the development of new ion exchange processes such as countercurrent regeneration, full-chamber bed, special resin, etc., the operating cost and the use of chemicals have been further reduced, and the combination system of RO/mixed bed has also been widely used.