Is it necessary to reuse wastewater: the experience of other countries
Savings of household resources – a rather difficult task. Particularly acute is the need to introduce a policy of “adjusting costs” for water supply. In this material, we will consider in detail the problem of reuse of wastewater. What is this practice, how much it allows you to save and as expedient as possible?
The process of regeneration
Regeneration of water – cleaning and refurbishment of spent liquid and precipitation. Purification involves the transformation of the sewage runoff into the water supply. The spent liquid is subject to the following stages of treatment:
· removal of mechanical particles;
· return of transparency;
The practice of reuse of water came to us from arid countries, where a litre of drinking water costs more than a litre of fuel. It seems strange for many compatriots to drink regenerated water (purified sewage liquid), but in most arid countries this is the only opportunity to offset the shortage of water resources. Regeneration can return more than 50% of wastewater, saving lives to hundreds of millions of people.
However, even developed countries that do not have an obvious shortage of water resources, today also pay attention to the process of regeneration of wastewater. The sewage can not only be drunk but also used for technical purposes. Regeneration to the state of technical water is much cheaper than the state of drinking.
Technical water is a liquid that can not be used in the food industry. You can not drink or use it for cooking. But it is great for watering the ground, washing and wash off in the toilet.
Regeneration of water is not necessarily a global event, as in central urban or district treatment plants. There are compact systems for the recycling of household or industrial water, which, with the permission of the city authorities, are installed at a specific facility.
In many countries of Europe, private systems for the regeneration of atmospheric precipitation and drainage fluids from the soil have become widespread. Buildings of this type allow reducing the load on the city collector system during the storms and spring floods.
City stations use budget technologies for water preparation, which require large-scale and long-time treatment facilities:
Object (private) treatment facilities are compact filtering stations, which instead of separation, defending and other measures listed above apply the following technologies:
· membrane cleaning;
· reverse osmosis
· multi-barrier filtration.
The degree of filtration in regeneration systems depends entirely on the requirements of consumers. That is, cleaning the waste liquid for food needs and watering the land has different degrees.
The role of technical water is suitable for the liquid with the presence of sodium salt, phosphates and other aggressive solutions. Such water is used for subsoil watering. That is, the technical water does not process the crown of bushes and trees. The technical fluid is fed immediately to the root system. Water for nutritional needs is subject to more qualitative cleaning.
In countries that do not have a clear shortage of drinking water, sewage is regenerated only to the state of the technical fluid.