In large utility systems, which type of wastewater discharge is usually an intermittent discharge?

In large utility systems, intermittent discharges are often associated with processes that generate wastewater only under specific operational conditions or during certain times. The demineralization system is a key component in many utility operations, particularly in power plants, where it is used to remove minerals from water to avoid scaling and other issues in boilers and turbines.

The demineralization process typically operates in cycles. Depending on the water quality and the demands of the system, it may produce wastewater intermittently when the ion exchange resins reach exhaustion and need regeneration. This regeneration process results in an occasional discharge of spent regenerant solutions, which is not continuous.

In contrast, sewage systems usually experience a more or less constant flow as they handle residential and industrial waste continuously. Cooling water discharges often occur on a continuous basis during operations, as they are necessary for heat exchange processes. Stormwater runoff can be intermittent depending on weather conditions, but it is not specifically categorized as a deliberate discharge process like that of the demineralization system. Therefore, the nature of wastewater from demineralization processes aligns with the characteristics of intermittent discharges in large utility systems.