Specific water consumption

During the designing of water-supply systems it’s necessary to know water volume, that has to be given by water-plumbing, types and number of water consumers, taking into account the perspective plan of object development, calculation norms of water consumption by each type of consumer and water consumption mode during the day.

Water consumption norm is a volume of water that is spent on certain needs during time unit, or for the unit of products that is produced. In settlements norms of economic-drinkable water consumption are appointed on the basis of study of actual water consuming volume and mode in analogical conditions, or, if it’s impossible, than by СНіП 2.04.02-84.

Average daily norms of economic-drinkable water consumption in settlements for one habitant (during year) with construction by houses, which are equipped with internal water-plumbing and sewage system, are the next: without baths – 125-160l/day; with baths and local water heaters – 160-230l/day; with centralized hot water-supply – 230-350l/day. In the settlements, where water consumption is carried out with the help of water intake geysers, specific expenses are equal to 30-50l/day. Needs of local industry and unforeseen expenses are taken into account by rising of specific water expenses on 5-10%.

Specific water expenses for industrial enterprises needs are depend on products’ type, that are produced, acceptable technology, installed equipment. These data are determined by a technological passport of enterprise. Water consumption norms by products’ unit are used for reference counts of water expenses. In such way, for example, it’s needed 7.5-12m³ of water for processing of 1t of milk at milk factory; 1.8-4.8m³ of water for production of 1t of bread at bread-baking plant; 10-40m³ of water for production of 1t of products at meat-packing plant; 18-25m³ of water for 1t of sugar at sugar-refinery; 8-28m³ of water for 1thousand of jars at fruit and vegetable cannery; 1.3-1.8m³ of water for 1thousand of bricks at brickwork. Besides industrial expenses at industrial enterprises, it’s needed to take into account economic-drinkable needs and water expenses by shower. Economic-drinkable needs are determined by the norm: 45l during shift for one person at workshops with heat emision more than 23.2Wt/m³; 25l in other workshops. Expenses are taken into account at the end of working shift from the calculation 500l/hour for one shower net during 45 minutes.

Specific water expenses on watering depend on natural and local conditions and are presented: for mechanical cleaning of passages and squares with improved coverage – 1.2-1.5 l/m² per one watering, mechanized watering of passages and squares – 0.3-0.4 l/m² per one watering, watering from hoses of the same passages – 0.4-0.5 l/m², watering of lawns, flower-gardens – 4-6 l/m² per one watering, watering of green planting and small holdings – 3-4 l/m² per day.

In default of data about the area of passages and green planting, which are watered, the specific expenses on watering are determined from calculation 50-90 l/day for one habitant in accordance with climate conditions (more at the south), providing the source with water (less at poorly provided source), degree of equipping with modern amenities of houses, and other local conditions.

Besides the regular providing economic-drinkable and industrial needs, the water-supply system should give water for fire extinguishing, if it is necessary. Water expenses on fire extinguishing are necessary only when fire takes place and, that’s why, they are taken into account only during checking calculations of water-plumbing network and while determination of spare reservoirs volumes (RCW, water-towers, fire-prevention reservoirs).

Water expends for external fire extinguishing at settlement and the calculation amount are given at the table 1.1

Table 1.1

Дата добавления: 2015-11-14