Final answer:
A dishwasher should be connected to the drainage system through secure plumbing methods such as a high loop or air gap. Devices in sinks can increase water flow rate, and greywater from dishwashing can be reused if separated from blackwater.
Step-by-step explanation:
A domestic dishwashing machine should be connected to the drainage system using appropriate plumbing techniques, which may involve a high loop to the sink drain or an air gap fitting. This is to ensure the waste water is properly expelled from the machine without the risk of backflow containing harmful contaminants into the machine or dwelling. It's important to use special detergents designed for dishwasher use, and to pre-scrape leftover food from dishes before washing.
The devices found in many sink drains, often shown in diagrams like Figure 12.28, are designed to significantly increase the flow rate of water. These can be simple design features like a smooth curve in the pipes, a venting system to negate vacuum effects, or special attachments that prevent clogs and promote smoother water flow. Chemical drain cleaners, which can be alkaline or acidic, are used to clear obstructions and are available in various forms.
Domestic activities that generate greywater, like laundry and dishwashing, can have their output reused if properly separated from blackwater, which contains human waste. In terms of the dishwashing process, using detergents with surfactants helps to reduce surface tension allowing faster drying and minimizes soap residue.