When purchasing private housing, it is imperative to delve into the question of what water supply and sanitation should be like according to SNiP, because water consumption is necessary for human household, drinking and communal needs. And the Building Codes and Rules regulate their arrangement.
The water consumption rate is the permissible maximum amount of water of appropriate quality that is necessary to meet the needs of people living in a certain housing. Water consumption rates are also determined by the rules adopted by executive authorities.
Dependence of water consumption
The amount of water consumption depends on the level and quality of life of people. Turning to history, we can note that in 1890, one resident of the capital used 11 liters of water every day. After 20 years, the Muscovite already needed 66 liters per day. On this moment According to SNiP standards, water consumption by Moscow residents has increased greatly and amounts to about 700 liters per day.
Water consumption directly depends on the climate where a person lives and the work he does. Doctors assure us that a person needs to consume up to 2 liters of fluid per day.
Plus, in different climatic conditions, the need for water is different. For example, in the southern regions it is required large quantity liquids than in the northern ones.
Difference in water consumption
Fluctuations depend on technology and on the habits of mankind. As we said earlier, the difference in fluid consumption is related to the climate of a person’s residence, but also to working conditions, more precisely on weekends. This affects the annual water consumption specified in SNiP. Diurnal fluctuations vary depending on the daily routine, in general, on sleep and wakefulness. In apartments, water consumption increases in winter due to central heating, compared to private houses or countryside. Partially, according to SNiP, water consumption per week depends on weekends and is 30%, these are always Saturdays and Sundays.
It has been proven that daily fluctuations in water consumption are associated not only with the time of day, but also with the organization of leisure time for household members, in particular this television programs, movies, holidays and others interesting events that take place at home. There is also a colossal difference in the consumption of cold and hot water.
On average, a family living in Russia with two children uses about 7,000 liters of hot water and 10,000 liters of cold water.
Daily water consumption standards
Water consumption standards SNiP according to the documentation are used for drinking and domestic needs. This includes cooking, daily hygiene, and much more. And for a private house, we also add washing the vehicle, watering the house area and flower beds, filling the pool, etc. Let's consider the daily water consumption standards of SNiP:
- Cooking – 3 liters;
- Drinking water – up to 2 liters;
- Hand washing (without stopping the water) – up to 8 liters;
- Oral hygiene (without stopping the water) – up to 7 liters;
- Toilet flushing – up to 12 liters at a time;
- Taking a shower – 20 liters/minute;
- Taking a bath – 150 liters;
- Washing – up to 100 liters;
- Washing dishes – up to 10 liters at a time.
In total, we get from 300 to 570 liters per day. From the calculation it is clear that water consumption by SNiP differs significantly from actual indicators. Therefore, it is logical to think about saving water consumption.
Standards for drainage in private houses
Drainage, like water supply, is an essential element of modern comfortable human life.
Living in a private house, the necessary amenities, such as a kitchen and a bathroom, also require the collection of used water, and not just water supply. And the SNiP water disposal for private houses per day per person is given below:
- With water supply and sewerage (without bath) - 120 liters;
- With running water and bathrooms – 225 liters;
- From the center hot water supply – 300 liters;
- From the center hot water supply (structure height more than 12 meters) - 400 liters.
Daily water drainage is uneven within 1 hour, but this difference is usually not taken into account when calculating costs, because water drainage takes into account the minimum and maximum coefficients per day, hours with general unevenness. According to the data, we see that water supply and sanitation SNiP do not even meet the planned indicators. For example, if a person lives in a house with running water, sewerage, and a bathroom and uses 500 liters of water, whereas according to the standards he is required to drain only 225 liters.
Estimated standards have long been exceeded by actual water consumption, so residents of private houses are trying to save money.
With the help of various filtering installations, you can use process water for other needs; of course, you should not drink it, but it is quite suitable for watering and washing your car.
The main types of water consumption are: household and drinking water consumption by residents of populated areas; water consumption industrial enterprises; water consumption associated with landscaping (watering streets, green spaces, etc.); use of water for fire extinguishing; own needs of the water supply system.
Domestic and drinking water consumption. Standards for household and drinking water consumption in populated areas are adopted according to SNiP 2.04.02 - 84 (Table 1.1).
For areas with buildings using water from standpipes, the specific average daily (per year) water consumption per inhabitant should be 30...50 l/day.
Specific water consumption includes water consumption for drinking and domestic needs in public buildings, excluding water consumption for holiday homes, sanatorium-tourist complexes and health camps.
The choice of specific water consumption within the limits specified in table. 1.1, should be carried out depending on climatic conditions, the power of the water supply source and water quality, the degree of improvement, the number of floors of the building and local conditions.
The amount of water for the needs of industry that provides the population with food, and unaccounted expenses, with appropriate justification, may be taken additionally in the amount of 10...20% of the total water consumption for household and drinking needs settlement.
Specific water consumption in settlements with a population of over 1 million people may be increased upon justification in each special case and coordination with State supervisory authorities.
The average daily (per year) volume of water consumption, m 3 /day, for household and drinking needs is determined by the formula
where q Ж1 is the rate of specific water consumption, l/(day per person), corresponding ith the degree of sanitary and technical improvement of residential buildings and taken according to table. 1.1; Ni - the estimated number of residents living in residential areas with the i-th degree of improvement, at the end of the construction phase under consideration.
The estimated number of inhabitants can be determined by the formula
Where Rj - j-th population density, people/ha; Fij, - area of residential development area with i-th degree of sanitary and technical improvement of buildings and j-th population density, hectares.
To correctly calculate water supply systems, it is necessary to know the order of their development and the water consumption corresponding to these orders. The increase in water consumption during the development of the system is due to an increase in population and an increase in the degree of sanitary and technical improvement of buildings. Accounting for the growth of water consumption is carried out by determining the estimated water consumption at the end of the corresponding development phase.
Water consumption for household and drinking needs in a populated area is uneven throughout the year. There are fluctuations in daily flow: seasonal, associated with changes in temperature and humidity at certain times of the year, A also weekly and daily allowances, due to the characteristics of water consumption on different days of the week (weekdays, weekends, pre-holidays and public holidays). Water supply systems must be designed to handle a maximum daily water flow, m3/day, equal to
where Ksut max = 1.1...1.3 - the maximum coefficient of daily unevenness of water consumption, taking into account the lifestyle of the population, the operating mode of enterprises, the degree of improvement of buildings, changes in water consumption by seasons of the year and days of the week, Qdaym - the estimated (average for the year) daily water consumption, m 3 /day, determined by formula (1.1).
In some cases, it is necessary to check the operation of the water supply system at a minimum daily water flow, m 3 / day, determined by the formula
Where TOdaysmin= 0.7...0.9 minimum coefficient of daily unevenness of water consumption.
Water consumption of industrial enterprises. At industrial enterprises (including agricultural production enterprises), water is spent on the technological needs of production, the household and drinking needs of workers, as well as for their use of showers.
Water consumption standards for technological needs depend on the adopted technological process, type of water supply system, water quality, etc.
Average volumes of water consumption are determined by the types of water used (recirculation, make-up) by multiplying the corresponding specific costs by the productivity of the technological process in accepted units (1 t, 1000 kW, etc.).
In accordance with SNiP 2.04.01-85, water consumption standards for household and drinking needs of workers of industrial enterprises are assumed to be equal for those working in workshops with a heat release of more than 84 kJ per 1 m 3 / h (hot shops) qr = 45 liters per shift per person; for other workshops qX = = 25 l.
The volume of water consumption per shift, m 3 /cm, is determined by the formula
Qx/n = qrnr + qxnx, (1.5)
Where Pr, PX - the number of workers, respectively, in workshops with a heat release of more than 84 kJ per 1 m 3 / h and in other workshops for the shift in question.
Water consumption for using a shower is determined based on hourly water consumption
for one shower net 500 l with a shower duration of 45 minutes. In this case, the water consumption for taking a shower after the end of the shift, m 3 / h, is determined by the formula
where N shower- the number of people using the shower in a given shift; A - number of people per shower net.
Water consumption associated with the improvement of urban areas and industrial sites. Water consumption standards for watering green spaces, as well as washing the streets of populated areas and territories of industrial enterprises are adopted according to SNiP 2.04.02--84, depending on the type of coverage of the territory, the method of watering it, the type of plantings, climatic and other local conditions (Table 1.2) .
The daily volume of water consumption, m 3 /day, for watering streets and green spaces is determined by the formula
where Qpol is water consumption for irrigation, l/m 2, taken according to the table. 1.2; F - gross area of the settlement (including streets, squares, etc.), hectares; a is the share of the irrigated area of the settlement, %.
In the absence of data on areas by type of improvement (green spaces, driveways, etc.), the average daily water consumption for irrigation during the irrigation season, m 3 /day, can be determined by the formula
Where qf p - specific rate of water consumption for irrigation per one resident of a settlement, taken equal to 50.. 90 l/day per person, depending on climatic conditions, power, source of water supply, degree of improvement of the settlement and other local conditions; N- estimated number of inhabitants in a locality.
Total daily water consumption determined by individual groups of consumers supplied with water by the calculated water supply system.
For a unified water supply system serving all of the listed consumer groups, determine: average daily water consumption, m 3 /day,
maximum daily water consumption, m 3 days,
In formulas (1.9) And (1.10) Qtech is the daily water consumption for the technological needs of industrial enterprises.
Water supply systems are calculated for the maximum daily water flow and are checked to ensure that they do not miss the calculated fire flow.
Use of water for fire extinguishing. In accordance with SNiP 2.04.02-84, water consumption for external fire extinguishing (per fire) and the number of simultaneous fires in a populated area for calculating the main (calculated ring) lines of the water supply network should be taken from the table. 1.3.
With zone water supply, water consumption for external fire extinguishing and the number of simultaneous fires in each zone should be taken depending on the number of residents living in the zone.
The number of simultaneous fires and water consumption per fire in populated areas with more than 1 million inhabitants. a person should be accepted in accordance with the requirements of the State Fire Supervision authorities.
For a group water supply, the number of simultaneous fires is taken depending on total number residents in populated areas connected to water supply.
Water consumption for external fire extinguishing of housing and industrial buildings for the calculation of connecting and distributed lines of the water supply network, as well as the water supply network within a microdistrict or block, should be taken for the building that requires the highest water consumption, according to table. 1.4.
Water consumption per fire for external fire extinguishing at industrial and agricultural enterprises should be taken for the building that requires the highest water consumption, according to Table. 1.5 and 1.6. The estimated number of fires depends on the area they occupy: one fire - with an area of up to 150 hectares, two fires - more than 150 hectares.
The estimated duration of fire extinguishing is 3 hours; for buildings of I and II degrees of fire resistance with fireproof load-bearing structures and insulation with production categories G and D - 2 hours.
The determination of the total fire-fighting water flow in a populated area is carried out depending on the location of industrial or agricultural enterprises.
Table 1.6 Water consumption standards for external fire extinguishing of industrial buildings with a width of 60 m or more
If the enterprise is located within the city, the calculated number of simultaneous fires (Table 1.3) includes fires from this enterprise. At the same time, the calculated water consumption should include the corresponding water consumption for fire extinguishing at these enterprises, if they are more than those indicated in the table. 1.3.
When the enterprise is located outside a populated area, the estimated number of simultaneous fires should be taken as follows:
with an enterprise area of up to 150 hectares and the number of residents in a settlement up to 10 thousand people - one fire (at the enterprise or in the settlement according to the highest water consumption); the same, when the number of residents in a settlement is over 10 to 25 thousand people - two fires (one at an enterprise and one in a settlement);
with a territory area of over 150 hectares and with the number of inhabitants in a settlement up to 25 thousand people, there are two fires (two at an enterprise or two in a settlement, depending on the highest fire rate).
when the number of residents in a settlement is more than 25 thousand people, water consumption should be determined as the sum of the required higher flow (at an enterprise or in a populated area) and 50% of the required lower flow (at an enterprise or in a populated area).
In all cases, the water consumption for external fire extinguishing in a populated area must be no less than the water consumption for fire extinguishing of residential and public buildings indicated in Table. 1.4.
Own needs of the water supply system. The water supply system should be considered as an industrial enterprise that consumes water for the household needs of workers, in technological processes and for fire fighting. The largest consumer of water used for its own needs in the water supply system is treatment facilities.
In accordance with SNiP 2.04.02-84, approximately average daily (per year) water consumption for the own needs of clarification and disinfection stations should be taken: when reusing wash water in the amount of 3...4% of the amount of water supplied to consumers; without reuse - 10...14%, for softening stations - 20...30%;
The volume of water consumption for the own needs of the water supply system affects the calculated productivity, m 3 /day, of water intake and treatment facilities (Fig. 1.1)
Where
- maximum daily water flow, m/day; α - coefficient taking into account the own needs of treatment facilities; for water intake structures a is taken equal to 1.03...1.04 at reuse water and 1.1...1.14 without reuse at clarification and iron removal stations, at softening stations 1.2...1.3; for treatment facilities, both with and without water reuse, 1.10...1.14 at softening and iron removal stations and 1.2...1.3 at softening stations.
Coursework assignment
The degree of fire resistance of the production building is II.
The width of buildings is up to 60 m.
The area of the enterprise is up to 150 hectares.
Volume of buildings:
I production building 100 thousand m 3
II production building up to 200 thousand m 3
Number of working shifts 3.
The number of workers per shift is 600 people.
Water consumption for production needs is 700 m 3 /cm.
The number of workers per shift taking a shower is 80%.
Initial data for the locality
The number of residents in the locality is 21 thousand people.
The building has 5 storeys.
The degree of improvement of residential areas: internal water supply, sewerage and centralized hot water supply
Type of public building: factory-kitchen (type “b”) with a volume of up to 2500 m 3 Meter for 5000 dishes.
Material of pipes of the main sections of the water supply network and water supply systems: cast iron with a polymer coating applied by centrifugation.
The length of water pipelines from NSII to the water tower is 700 m.
1. Determination of water consumers and calculation of the required water consumption for drinking, industrial and fire needs of the village and enterprise
1.1 Determination of water consumers
The combined utility, drinking and fire-fighting water supply system must ensure the flow of water for the utility and drinking needs of the village, the utility and drinking needs of the enterprise, the utility and household needs of public buildings, the production needs of the enterprise, and extinguishing possible fires in the village and at the enterprise.
1.2 Calculation of required water consumption for household, drinking and production needs
Water consumption standards for household and drinking needs for populated areas are determined according to SNiP 2.04.02-84, clause 2.1, table 1, note 4 and depend on the degree of improvement of residential areas. We take the water consumption rate per person to be 300 l/day.
Estimated (average for the year) daily water consumption, m 3 / day for household and drinking needs
q - specific water consumption per inhabitant, taken according to Table 1 of SNiP 2.04-84; Nf – estimated number of inhabitants.
, m 3 / day.
Daily consumption, taking into account water consumption for the needs of industry providing food to the population, and unaccounted expenses increases by 10-20% (clause 2.1, note 4).
Estimated water consumption per day of greatest water consumption
K sum.max – coefficient of daily unevenness of water consumption;
To sum.max – takes into account the lifestyle of the population, the operating mode of the enterprise, the degree of improvement of buildings, changes in water consumption by season of the year and days of the week.
For buildings equipped with internal water supply, sewerage and centralized hot water supply, we accept K sum.max = 1.1.
Estimated hourly maximum water flow
Kh.max – coefficient of hourly unevenness of water consumption;
where a max is a coefficient that takes into account the degree of improvement of buildings, the operating mode of enterprises and other local conditions, adopted according to clause 2.2.
b max – coefficient taking into account the number of residents in a locality, is taken according to Table 2, clause 2.2.
, m 3 /day
Water consumption for domestic and drinking needs in public buildings
q general building – the rate of water consumption by consumers per day for a public building is adopted according to Appendix 3;
N total building – number of meters.
Water consumption for household and drinking needs of the factory-kitchen
m 3 /day
Total water consumption in the village.
M 3 /day
Industrial enterprise.
In accordance with clause 2.4. , Appendix 3 and according to the assignment, we accept the norm of water consumption for household and drinking needs per person per shift 
Water consumption per shift
N cm – number of workers per shift.
m 3 /cm
Daily water consumption
Where
n cm – number of shifts.
m 3 /day
Number of shower nets
where N cm is the number of workers taking a shower.
PC.
Water consumption per shift
0.5 m 3 / h – water consumption rate per shower net (Appendix 3);
Daily water consumption per shower
where n cm is the number of shifts; n cm =3.
m 3 /day
Water consumption for the production needs of the enterprise as specified by m 3 /cm, which is distributed evenly over the hours of the shift (an eight-hour shift with a one-hour lunch break, during which production does not stop). Eight hour shifts accepted
Hourly water consumption
m 3 / h
Daily water consumption for production needs
Thus, the estimated daily water consumption for the enterprise will be
The total water consumption per day for the village and enterprise is equal to
In the village and enterprise, the greatest water consumption occurs from 8 to 9 o'clock, at this time 574.3 m 3 / h or
l/s
Estimated consumption for the enterprise
l/s
Estimated consumption of a public building (hospital).
l/s
The village spends
We plot the water consumption of the combined water supply system by hour of the day (Fig. 1).
Fig. 1 - Determination of estimated water consumption for fire extinguishing
Estimated water consumption for external fire extinguishing in populated areas and at an industrial enterprise is determined according to SNiP 2.04.02-84, paragraphs 2.12-2.23, and for internal fire extinguishing according to SNiP 2.04.01-85, paragraphs 6.1-6.6.
Since the water supply system in the village is designed to be integrated, then according to SNiP 2.04.02-84, clause 2.23, with a population of 21,000 people, we accept 1 fire. With a five-story building, water consumption is 15 l/s per fire.
Water consumption for internal fire extinguishing in a village in the presence of a kitchen factory with a volume of up to 2500 m 3, according to SNiP 2.04.01-85, clause 61, table 1, we accept 1 jet with a capacity of 2.5 l/s
According to SNiP 2.04.02-84, clause 2.22, the enterprise accepts one fire, because enterprise area up to 150 hectares.
According to clause 2.14, table 8, note 1, the estimated water consumption for the building is accepted
According to SNiP 2.04.01-85, clause 61, table 2, the estimated flow rate for internal fire extinguishing in an industrial building is taken at the rate of 2 jets of 5 l/s each:
l/s
2. Hydraulic calculation of the water supply network
Total water consumption per hour of maximum water consumption, i.e. from 8-9 o'clock, is 159.53 l/s, including the concentrated consumption of the enterprise is 34.83 l/s, and the concentrated consumption of a public building is 0.58 l/s.
Figure 2 – Design diagram of the water supply network.
1. Let's determine the uniformly distributed flow rate:
2. Determine the specific consumption:
l/s
where is the length of the section;
m – number of sections;
j – section number.
3. Let’s determine the route selections:
The results are shown in Table 1.
Table 1 – Travel expenses
| Plot number | Section length, m | Track selection, l/s |
| 1-2 | 1000 | 12,412 |
| 2-3 | 1500 | 18,618 |
| 3-4 | 1000 | 12,412 |
| 4-5 | 1500 | 18,618 |
| 5-6 | 1500 | 18,618 |
| 6-7 | 500 | 6,206 |
| 7-1 | 1000 | 12,412 |
| 7-4 | 2000 | 24,824 |
| 10000 | 124,12 |
4. Let's determine the nodal costs:
,
where is the sum of track selections in areas adjacent to a given node;
Table 2 - Nodal costs
5. Let's add concentrated costs to the nodal costs. The concentrated flow rate of the enterprise is added to the nodal flow rate at point 5, and the concentrated flow rate of a public building at point 3.
Then q 3 =15.515+0.58=16.095 l/s, q 5 =18.618+34.83=53.448 l/s
The values of nodal flow rates are shown in Fig. 3 including concentrated costs
Figure 3 – Design diagram of the water supply network with nodal flow rates.
6. Let's perform a preliminary distribution of water flows across network sections. Let's do this first for the water supply network at maximum economic and industrial water consumption (without fire).
The dictating point is point 5. We have previously outlined the direction of water movement from point 1 to point 5 (the direction is shown in Fig. 3). water flows can approach point 5 in three directions: the first is 1-2-3-4-5, the second is 1-7-4-5, the third is 1-7-6-5. For node 1 the relation must be satisfied 
. Values l/s and 
.
, .
The result will be:
Check l/s.
In the event of a fire, the water supply network must ensure the supply of water for fire extinguishing at a maximum hourly water consumption for other needs, with the exception of expenses at an industrial enterprise for showers, watering the territory, etc. (clause 2.21), if these costs are included in the consumption during the hour of maximum water consumption. For the water supply network shown in Fig. 2, the water flow for fire extinguishing should be added to the nodal flow at point 5, where water is taken to the industrial enterprise and which is the most distant from the input point (from point 1), i.e.
A diagram of a water supply network with pre-allocated flow rates during normal times is shown in Fig. 4.
Figure 4 - Design diagram of the water supply network with pre-allocated costs for domestic and industrial water consumption
In the event of a fire, the water supply network must ensure the supply of water for fire extinguishing at the maximum hourly water consumption for other needs, with the exception of expenses at an industrial enterprise for showers, watering the territory, etc. (clause 2.21 SNiP 2.04.02-84), if these costs were included in the hour of maximum water consumption.
Hydraulic calculation of the network in case of fire.
Since , the nodal costs during a fire will be different than during the hour of maximum water consumption without a fire, we will determine the nodal costs as they were calculated without a fire
For node 1 the relation must be satisfied . Values l/s and 
l/s are known and unknown. We set arbitrarily one of these quantities. Let's take, for example, l/s. Then,
For point 7 the following relationship must be observed
.
The values of l/s and l/s are known and unknown. We set arbitrarily one of these values and accept, for example, l/s. Then,
Water consumption in other areas can be determined from the following ratios:
, .
The result will be:
Check l/s.
Figure 5 - Design diagram of the water supply network with nodal and pre-distributed costs in case of fire.
7. Determine the diameters of the pipes of the network sections.
For cast iron pipes.
By economic factor and pre-distributed water flow across network sections in case of fire, according to Table 3, cast iron pipes GOST 9583-75 and GOST 21053-75, we determine the diameters of the pipes of sections of the water supply network:
Linking the water supply network with maximum economic and industrial water consumption.
Linking is carried out until ∆h ≤ 0.5 m
∆q ’ = ∆h / 2∑(h/q)
For section 4–7, which is common to both rings, two corrections are introduced - from the first ring and from the second. The sign of the correction flow when transferred from one ring to another should be preserved.
Determination of pressure losses at maximum household and industrial water consumption.
Where , 
, 
The pressure loss in the network at maximum economic and industrial water consumption is: h c = 10.9596 m.
Determination of pressure losses at maximum household and industrial water consumption and fire.
Water flows from point 1 to point 5 (dictating point), as can be seen from the directions of the arrows, can go in 3 directions: the first - 1-2-3-4-5, the second - 1-7-4-5
Water flows from point 1 to point 5 (dictating point), as can be seen from the directions of the arrows, can go in 3 directions: the first - 1-2-3-4-5, the second - 1-7-4-5, the third - 1-7-6-5. The average pressure loss in the network can be determined by the formula
Where , ,
The pressure loss in the network at maximum economic and industrial water consumption (without shower costs at the enterprise) and in case of fire is
h 1 = 2.715+6.2313+6.6521+11.9979=27.5927 m
h 2 = 2.5818+12.8434+11.9970=27.4722 m
h 3 = 2.5818+3.6455+21.1979= 27.4234 m
3. Determination of the operating mode of the NS- II
The choice of operating mode of the second lift pumping station is determined by the water consumption schedule. During those hours when the supply of NS-II is more than the water consumption of the village, excess water flows into the water tower tank, and during the hours when the supply is less than the water consumption of the village, a shortage of water comes from the water tower tank. To ensure a minimum tank capacity, the water supply schedule by pumps is sought to be brought closer to the water consumption schedule. However, frequent switching on and off of pumps complicates the operation of the pumping station and negatively affects the electrical control equipment of the pumping units. Installation large group pumps with low flow leads to an increase in the area of NS-II and the efficiency of pumps with low flow is lower than with higher flow. Therefore, a two or three-stage operating mode of NS-II is adopted.
In any mode of operation of NS-II, the supply of pumps must fully (100%) ensure the water consumption of the village. We accept a two-stage operating mode of NS-II with each pump supplying 2.5% per hour of daily water consumption. Then one pump will supply 2.5*24 = 60% of the daily water consumption per day. The second pump must supply 100-60 = 40% of the daily water flow and must be turned on for 40/2.5 = 16 hours.
In accordance with the water consumption schedule, it is proposed to turn on the second pump at 5 o’clock and turn it off at 21. This mode is shown with a dotted line.
To determine the regulating capacity of the water tower tank, let's draw up Table 3.
Table 3 - Water consumption and pump operating mode
| Times of Day | Hourly water consumption | 1 option | Option 2 | ||||||
| Pump supply | Receipt into the tank | Flow from tank | Remaining in tank | Pump supply | Receipt into the tank | Flow from tank | Remaining in tank | ||
| 0-1 | 2,820 | 2,5 | 0 | 0,32 | -0,32 | 3 | 0,18 | 0 | 0,18 |
| 1-2 | 2,530 | 2,5 | 0 | 0,03 | -0,35 | 3 | 0,47 | 0 | 0,65 |
| 2-3 | 2,330 | 2,5 | 0,17 | 0 | -0,18 | 3 | 0,67 | 0 | 1,32 |
| 3-4 | 2,370 | 2,5 | 0,13 | 0 | -0,05 | 3 | 0,63 | 0 | 1,95 |
| 4-5 | 3,120 | 2,5 | 0 | 0,62 | -0,67 | 3 | 0 | 0,12 | 1,83 |
| 5-6 | 3,800 | 2,5 | 0 | 1,3 | -1,97 | 3 | 0 | 0,8 | 1,03 |
| 6-7 | 4,370 | 5 | 0,63 | 0 | -1,34 | 3 | 0 | 1,37 | -0,34 |
| 7-8 | 4,980 | 5 | 0,02 | 0 | -1,32 | 3 | 0 | 1,98 | -2,32 |
| 8-9 | 5,730 | 5 | 0 | 0,73 | -2,05 | 6 | 0,27 | 0 | -2,05 |
| 9-10 | 5,560 | 5 | 0 | 0,56 | -2,61 | 6 | 0,44 | 0 | -1,61 |
| 10-11 | 5,370 | 5 | 0 | 0,37 | -2,98 | 6 | 0,63 | 0 | -0,98 |
| 11-12 | 5,290 | 5 | 0 | 0,29 | -3,27 | 6 | 0,71 | 0 | -0,27 |
| 12-13 | 4,620 | 5 | 0,38 | 0 | -2,89 | 6 | 1,38 | 0 | 1,11 |
| 13-14 | 4,570 | 5 | 0,43 | 0 | -2,46 | 6 | 1,43 | 0 | 2,54 |
| 14-15 | 4,800 | 5 | 0,2 | 0 | -2,26 | 6 | 1,2 | 0 | 3,74 |
| 15-16 | 4,980 | 5 | 0,02 | 0 | -2,24 | 6 | 1,02 | 0 | 4,76 |
| 16-17 | 5,470 | 5 | 0 | 0,47 | -2,71 | 6 | 0,53 | 0 | 5,29 |
| 17-18 | 4,790 | 5 | 0,21 | 0 | -2,5 | 4 | 0 | 0,79 | 4,5 |
| 18-19 | 4,640 | 5 | 0,36 | 0 | -2,14 | 3 | 0 | 1,64 | 2,86 |
| 19-20 | 4,370 | 5 | 0,63 | 0 | -1,51 | 3 | 0 | 1,37 | 1,49 |
| 20-21 | 4,160 | 5 | 0,84 | 0 | -0,67 | 3 | 0 | 1,16 | 0,33 |
| 21-22 | 3,720 | 5 | 1,28 | 0 | 0,61 | 3 | 0 | 0,72 | -0,39 |
| 22-23 | 3,110 | 2,5 | 0 | 0,61 | 0,00 | 3 | 0 | 0,11 | -0,5 |
| 23-24 | 2,520 | 2,5 | 0 | 0,02 | -0,02 | 3 | 0,48 | 0 | -0,02 |
| V tank = | 3,88 | V tank = | 7,61 | ||||||
Column 1 shows hourly intervals, and column 2 shows hourly water consumption as a percentage of daily water consumption in accordance with column 11 of table 1. Column 3 shows the supply of pumps in accordance with the proposed operating mode of NS-II.
If the pump supply is higher than the water consumption of the village, then the difference between these values is recorded in column 4 (flow into the tank), and if lower - in column 5 (tank flow).
The remaining water in the tank (column 6) at the end of a certain interval is determined as the algebraic sum of two columns 4 and 5 (positive when entering the tank and negative when flowing out of it).
The regulating capacity of the tank will be equal to the sum of the absolute values of the largest positive and smallest negative value in column 6. In the example considered, the capacity of the tower tank turned out to be equal to 3.88% of the daily water consumption.
Let's try to analyze another mode of operation of NS-II. By setting the pump flow to 3% of the daily water consumption of each pump. One pump will supply 24*3 = 72% of the daily flow in 24 hours. The other will share 28% and must work 28/3 = 9.33 hours. The second pump must be turned on from 8 to 17 hours 20 minutes. This mode of operation of the NS-II is shown on the graph by a dash-dot line. The regulating capacity of the tank is equal to
7.61%, i.e. in this mode, the tank capacity will be greater. We choose the first option with a pump supply of 2.5% of the daily one.
4. Hydraulic calculation of water pipelines
The purpose of the hydraulic calculation of water pipelines is to determine the pressure loss when the calculated water flow is passed through. Water pipelines, like the water supply network, are designed for two modes of operation: for the passage of utility, drinking and production expenses in accordance with the operating mode of NS-II and for the passage of maximum utility, drinking, production and fire expenses, taking into account the requirements of clause 2.21 of SNiP 2.04. 02-84. The method for determining the diameter of water pipeline pipes is the same as the diameter of water supply network pipes.
In this course project it is given that the water pipelines are made of asbestos-cement pipes, the distance from NS-II to the water tower is m.
Considering that the project adopted an uneven operating mode of PS-II with a maximum pump flow P = 2.5 + 2.5 = 5% per hour of daily water consumption, the water flow that will pass through the water pipelines will be equal to:
Since water pipelines should be laid in at least two threads, the water flow through one water pipeline is equal to:
l/s
From Appendix II of the guidelines, we determine the diameter of the water pipelines: d = 0.280 m, d p = 0.229 m.
The speed of water in the water pipeline is determined from the expression:
At water flow rate Q = 69.63 l/s, the speed of water movement in a water pipeline with a design diameter of 0.229 m. will be equal to:
m/s
The pressure loss in the water pipeline is determined by the formula:
h water =0.012 700=8.4 m
The total water consumption in fire extinguishing conditions is equal to
l/s
The water flow in one line of water pipelines under fire extinguishing conditions will be equal to:
In this case, the speed of water movement in the pipeline will be equal to:
m/s
h water =0.028 700=19.6 m
Pressure losses in water pipelines at (h water, h water.fire) will be taken into account when determining the required pressure of utility and fire pumps.
5. Calculation of the water tower
The water tower is intended to regulate uneven water consumption, store an emergency fire-fighting water supply and create the required pressure in the water supply network.
5.1 Determination of the height of the water tower
The height of the water tower is determined by the formula:
where 1.1 is a coefficient that takes into account pressure losses in local resistances (clause 4, appendix 10);
h с – pressure loss of the water supply network when it operates at normal times;
Z AT, Z V.B. – geodetic marks at the dictating point and at the location of the tower, respectively. The minimum pressure H St at the dictating point of the network with maximum domestic and drinking water consumption at the entrance to the building in accordance with clause 2.26 of SNiP 2.04.02-84 should be equal to:
where n is the number of floors
5.2 Determination of water tower tank capacity
The capacity of the water tower tank must be equal (clause 9.1. SNiP 2.04.02-84).
where W speech is the regulating capacity of the tank;
W N.Z. – the volume of emergency water reserve, the value of which is determined in accordance with clause 9.5 of SNiP 2.04.02-84 from the expression:
where is the supply of water required for a 10-minute duration of extinguishing one external and one internal fire;
Water supply for 10 minutes, determined by the maximum water consumption for household, drinking and production needs.
The regulating volume of water in containers (reservoirs, tanks, water towers) should be determined based on the schedules of water intake and withdrawal, and in their absence, according to the formula given in clause 9.2. SNiP 2.04.02-84. In this course work a water consumption schedule was determined and the operating mode of NS-II was proposed, for which the regulating volume of the water tower tank was K = 3.88 of the daily water consumption in the village (section 4)
Where 
m 3 /day.
Since the largest estimated water consumption is required to extinguish one fire at an enterprise, then
m 3
Thus
According to Appendix III of the guidelines, we accept a typical water tower with a height of 32.5 m with a tank with a capacity of W B = 800 m 3.
Knowing the capacity of the tank, we determine its diameter and height
m
6. Calculation of tanks clean water
Clean water reservoirs are designed to regulate the uneven operation of the pumping station on lifts I and II and to store an emergency supply of water for the entire fire extinguishing period.
The regulating capacity of clean water reservoirs can be determined based on an analysis of the operation of pumping stations of the first and second rises.
The operating mode of NS-I is usually assumed to be uniform, since this mode is most favorable for NS-I equipment and water treatment facilities. In this case, NS-I, as well as NS-II, must supply 100% of the daily water consumption in the village. Consequently, the hourly water supply of NS-I will be 100/24 = 4.167% of the daily water consumption in the village. The operating mode of NS-II is given in section 3.
Fig.7. - Operating mode of NS-I and NS-II
To determine W reg. Let's use the graphic-analytical method. To do this, we combine the operating schedules of NS-I and NS-II (Fig. 8). The regulating volume as a percentage of the daily water flow is equal to area “a” or an equal sum of areas “b”.
W reg = (5-4.167)*16 = 13.33% or
W reg = (4.167-2.5)*6 + (4.167-2.5)*2 = 13.33%
The daily water consumption is 10026.85 m3 and the regulating volume of the clean water reservoir will be equal to:
Emergency water supply W n.c. in accordance with clause 9.4. SNiP 2.04.02.-84 is determined from the condition of ensuring fire extinguishing from external hydrants and internal fire hydrants (clauses 2.12.-2.17., 2.20., 2.22.-2.24. SNiP 2.04.02.-84 and clauses 6.1.-6.4. SNiP 2.04.01.-85), as well as special fire extinguishing means (sprinklers, deluges and others that do not have their own tanks) in accordance with paragraph 2.18. and 2.19. SNiP 2.04.02.-84 and ensuring maximum drinking and production needs for the entire fire extinguishing period, taking into account the requirements of clause 2.21.
Thus:
When determining the volume of emergency water reserves in tanks, it is allowed to take into account their replenishment with water during fire extinguishing, if water supply to the tanks is carried out by water supply systems of categories I and II according to the degree of water supply, i.e.:
where t t =3 hours is the estimated duration of fire extinguishing (clause 2.24 of SNiP 2.04.02.-84).
When determining Q pos.pr, water consumption for watering the area, taking a shower, washing floors and washing technological equipment at an industrial enterprise is not taken into account.
In this example, Q¢ pos.pr -Q shower = 764.96-0 = 764.96 m 3 / h
Q¢ pos.pr = 764.96 m 3 /h or 212.49 l/s.
W n.z.x-p = Q¢ pos.pr . t t = 764.96 . 3 = 2294.88 m3.
During fire extinguishing, NS-I pumps supply 4.167% of the daily flow per hour, and during time t t will be supplied
Thus, the volume of the emergency water supply will be equal to:
Full volume of clean water tanks
According to clause 9.21. SNiP 2.04.02-84 the total number of tanks must be at the same levels, when one tank is turned off, at least 50% of the NC must be stored in the others, and the equipment of the tanks must provide the ability to turn on and empty each tank. We accept two standard tanks with a volume of 1600 m 3 (Appendix IV of the guidelines).
7. Selection of pumps for the second lift pumping station
From the calculation it follows that NS-II operates in an uneven mode with the installation of two main utility pumps, the flow of which will be equal to:
The required pressure of household pumps is determined by the formula:
where h water – pressure loss in water pipelines, m;
H N.B. – height of the water tower, m;
Z V.B. and Z N.S. – geodetic marks, respectively, of the installation site of the tower and PS-II;
1.1 – coefficient taking into account pressure losses due to local resistance (clause 4, appendix 10).
The pressure of pumps when operating during a fire is determined by the formula:
where h water.fire and h s.fire are, respectively, pressure losses in water pipelines and the water supply network during fire fighting, m;
H St – free pressure at the hydrant located at the dictating point, m. For low pressure water supply systems H St = 10 m;
Z AT – geodetic mark at the dictating point, m.
We build the pumping station on the low pressure principle. During normal times, one or a group of utility pumps are running. In the event of a fire, an additional pump is activated with the same pressure as the household pumps and ensures the supply of water for fire extinguishing. The design of the switching chamber depends on the type of pumping station (Fig. 9).
The selection of pump brands can be carried out according to the summary graph of the Q-H fields (Appendix XI and XII). On the graph, the pump flow is plotted along the abscissa axis, the pressure is plotted along the ordinate axis, and for each brand of pump the fields within which these values can change are shown. The fields are formed as follows. The upper and lower limits are characteristics, respectively.
Q-H for a given brand of pump with the largest and smallest impeller diameters of the produced series. The side borders of the fields limit the area optimal mode pump operation, i.e. area corresponding to the maximum values of the coefficient useful action. When choosing a pump brand, it is necessary to take into account that the calculated values of the pump’s flow and pressure must lie within its Q-H field.
The proposed pumping unit must ensure the minimum amount of excess pressure developed by the pumps in all operating modes, through the use of control tanks, regulation of the speed, changing the number and type of pumps, replacing impellers in accordance with changes in their operating conditions during the design period (clause. 7.2.SNiP 2.04.02-84).
The calculated values of supply and pressure, accepted brands and number of pumps, category of the pumping station are given in Table 4.
Table 4 - Calculated values of supply and pressure, accepted brands and number of pumps, category of pumping station
Bibliography:
1. SNiP 2.04.02-84 “Water supply. External networks and structures.” – M.: Stroyizdat, 1985.
2. SNiP 2.04.01-85 “Internal water supply and sewerage of buildings.” – M.: Stroyizdat, 1986.
3. Shevelev F.A., Shevelev A.F. “Tables for hydraulic calculation of water pipes.” / Reference manual. – M.: Stroyizdat, 1984.
4. Lobachev P.V. “Pumps and pumping stations”, M.: Stroyizdat, 1983.
(household and drinking needs).
The annual volume of water consumption for household and drinking needs of the enterprise Ukrainian State Center for the Operation of Specialized Cars (Ukrspetsvagon) is determined by the formula:
W xp = W p + W d + W st + W pr + W m + W fri, m³/year
5.3.1. Volume of water consumption for drinking needs of workers and employees.
The company currently employs 1,848 people, of which 992 are workers, 266 are office workers, 590 are workers in workshops with heat generation over 84 kJ.
The annual volume of water consumption for drinking needs of workers and employees is determined by the formula:
W p = ∑q n n n N 0.001
W p = ((25 972 + 45 590 + 15 266) 252 + 20 25 365)) 0.001 =
14002.2 m³/year.
W bp p = W p 0.015 = 14002.2 0.015 = 210.0 m³/year.
Then, the volume of water disposal will be:
W in p = 14002.2 – 210.0 = 13792.2 m³/year.
5.3.2. Volume of water consumption for shower installations.
The annual volume of water consumption for shower installations is determined by the formula:
W d = q n N k
W d = 0.5 248 2 252 = 62496.0 m³/year.
The volume of irrecoverable losses is 2.5%, i.e.
W bp d = W d 0.025 = 62496.0 0.025 = 1562.4 m³/year.
W water = 62496.0 – 1562.4 = 60933.6 m³/year.
5.3.3. Volume of water consumption for canteen needs.
In canteens, fresh water is used for cooking, washing and rinsing dishes. A washing machine is used to wash and rinse dishes. Water consumption for operating a dishwasher is determined by the formula:
W st = n t T
W st = 0.38 5 252 = 478.8 m³/year.
Water consumption for cooking is determined by the formula:
W p = q m T
W p = 0.012 1460.0 252 = 4415.0 m³/year.
The total annual water consumption for the needs of the canteen will be:
W st = 478.8 + 4415.0 = 4893.8 m³/year.
The volume of irrecoverable losses is 2%, i.e.
W bp st = W st 0.02 = 4893.8 0.02 = 97.9 m³/year.
The volume of water disposal will be:
W in st = 4893.8 – 97.9 = 4795.9 m³/year.
5.3.4. Amount of water consumption for laundry.
The laundry is used for washing industrial clothes.
The annual volume of water consumption of a laundry is determined by the formula:
W pr = q n N
W pr = 0.075 220 252 = 4158.0 m³/year.
The volume of irrecoverable losses is 30%, i.e.
W bp pr = W pr 0.3 = 4158.0 0.3 = 1247.4 m³/year.
Then the volume of water disposal will be:
W in pr = 4158.0 – 1247.4 = 2910.6 m³/year.
4.3.5. Volume of water consumption for medical posts.
In first-aid posts, patients are received and medical procedures are performed. Medical posts are visited by 37,296 people per year (or 148 people/day).
The annual volume of water consumption of medical posts is determined by the formula:
W m = 0.015 37296.0 = 559.4 m³/year.
The volume of irrecoverable losses is 1.5%, i.e.
W bp m = W m 0.015 = 559.4 0.015 = 8.4 m³/year.
Then the volume of water disposal will be:
W in m = 559.4 – 8.4 = 551.0 m³/year.
5.3.6. Watering the territory
The volume of water consumption for watering the territory is calculated using the formula:
W pt = ∑q i S i n 0.001
W fri = (5 72000 + 0.5 27000) 50 0.001 = 18675.0 m³/year
The volume of irreversible water consumption is equal to the volume of water consumption, i.e.
W bw fri = 18675.0 m³/year
Thus, the total volume of water consumption for household and drinking needs of the enterprise Ukrainian State Center for the Operation of Specialized Cars (Ukrspetsvagon) will be:
W xp = W p + W d + W st + W pr + W m + W pt
W xn = 14002.2 + 62496.0 + 4893.8 + 4158.0 + 559.4 + 18675.0 =
104784.4 m³/year.
The volume of irreversible water consumption will be:
W bw xp = 18675.0 m³/year.
The volume of irrecoverable losses will be:
W bp xp = W bp p + W bp d + W bp st + W bp pr + W bp m
W bp xp = 210.0 + 1562.4 + 97.9 + 1247.4 + 8.4 = 3126.1 m³/year.
Hence the volume of water disposal will be:
W in xp = W in p + W in d + W in st + W in pr + W in m
W in HP = 13792.2 + 60933.6 + 4795.9 + 2910.6 +551.0 =
82983.3 m³/year.
The water balance data of the enterprise Ukrainian State Center for the Operation of Specialized Cars (Ukrspetsvagon) are summarized in Table 5.2.
Table 5.2.
Water balance of the enterprise Ukrainian State Center for the Operation of Specialized Cars (Ukrspetsvagon).
| Water use | Annual volume (m³/year) | Daily volume (m³/day) |
| Water consumption | ||
| TOTAL: including: for technological needs for auxiliary needs for household and drinking needs | 334553,9 175921,3 53848,2 104784,4 | 1327,5 698,0 213,7 415,8 |
| Irrevocable losses | ||
| 14574,4 4895,0 6553,3 3126,1 | 57,8 19,4 26,0 12,4 | |
| Irreversible water consumption | ||
| TOTAL: including: in technological processes in auxiliary processes for domestic and drinking water use | 86295,7 62072,7 5548,0 18675,0 | 342,4 246,3 22,0 74,1 |
| Water disposal | ||
| TOTAL: including: from technological processes from auxiliary processes from household and drinking water use | 233683,8 108953,6 41746,9 82983,3 | 927,3 432,3 165,7 329,3 |
5.4. Calculation of specific balance standards for water consumption and wastewater disposal.
5.4.1. The value of the specific balance norm of water consumption (N b. s) is determined by the formula:
N b. s = N b.tech + N b.vsp + N b.khp
where: N b.tech = W tech / Q s; N b.vsp = Wvsp / Q s; N b.hp = W xp / Q s.
Accepted for calculation: W tech = 175921.3 m³/year; Wsp = 53848.2 m³/year; W hp = 104784.4 m³/year; Q s = 190,000 thousand UAH.
N b.tech = 175921.3 / 190000 = 0.926 m³/thous. UAH;
N b.vsp = 53848.2 / 190000 = 0.283 m³/thousand. UAH;
N b.x = 104784.4 / 190000 = 0.551 m³/thous. UAH,
N b. s = 0.926 + 0.283 + 0.551 = 1.76 m³/thousand. UAH
5.4.2. The value of the specific balance rate of circulating water (H about s) is determined by the formula:
N about s = N about those + N about vsp
where: N about vsp = W about those / Q s; N about vsp = W about vsp / Q s .
Accepted for calculation: W about those = 112670.0 m³/year; Wvsp = 274176.0 m³/year.
N about those = 112670.0 / 190000 = 0.593 m³/thous. UAH;
N about vsp = 274176.0 / 190000 = 1.443 m³/thous. UAH;
N about s = 0.547 + 1.443 = 2.036 m³/thousand. UAH
5.4.3. The value of the specific balance norm of irrecoverable water consumption (N bw s) is determined by the formula:
N bv s = N bv tech + N bv vsp + N bv x
where: N bv tech = W bv tech / Q s; N bv vsp = W bv vsp / Q s; N bv x = W bv xp / Q s.
Accepted for calculation: W bw tech = 62072.7 m³/year; W bvsp = 5548.0 m³/year;
W bw xp = 18675.0 m³/year;
N bw tech = 62072.7 / 190000 = 0.327 m³/thous. UAH;
N bv vsp = 5548.0 / 190000 = 0.029 m³/thous. UAH;
N bv xp = 18675.0 / 190000 = 0.098 m³/thous. UAH;
N bv s = 0.327 + 0.029 + 0.098 = 0.454 m³/thous. UAH
5.4.4. The value of the specific balance rate of irrecoverable losses (N bp s) is determined by the formula:
N bp s = N bp tech + N bp vsp + N bp x
where: N bp tech = W bp tech / Q s; N bp vsp = W bp vsp / Q s; N bp x = W bp xp / Q s.
Accepted for calculation: W bp tech = 4895.0 m³/year; W bp vsp = 6553.3 m³/year; W bp xp = 3126.1 m³/year.
N bp tech = 4895.0 / 190000 = 0.026 m³/thous. UAH;
N bp vsp = 6553.3 / 190000 = 0.034 m³/thous. UAH;
N bp x = 3126.1 / 190000 = 0.016 m³/thous. UAH,
N bp s = 0.026 + 0.034 + 0.016 = 0.076 m³/thous. UAH
5.4.5. The value of the specific balance norm of water disposal (N bv s) is determined by the formula:
N in s = N in those + N in vsp + N in x
where: Н in those = W in those / Q s; N in vsp = W in vsp / Q s; N in x = W in xn / Q s.
Accepted for calculation: W in those = 108953.6 m³/year; W in vsp = 41746.9 m³/year; W in HP = 82983.3 m³/year.
N in those = 108953.6 / 190000 = 0.573 m³/thousand. UAH;
Nvsp = 41746.9 / 190000 = 0.220 m³/thous. UAH;
N in x = 82983.3 / 190000 = 0.437 m³/thous. UAH,
N in s = 0.573 + 0.220 + 0.437 = 1.23 m³/thous. UAH
The results of calculations of specific balance standards of water consumption, irrecoverable water consumption, irrecoverable losses and water disposal are presented in Tables 5.3; 5.4; and 5.5.
7. Calculation of water consumption and wastewater disposal limits
For operational control over the amount of water consumed and discharged, enterprises are set limits on water consumption and disposal.
Water consumption limits are the estimated amount of design water, determined taking into account their production program, water consumption standards, measures to reduce water consumption and the coefficient of unevenness of its consumption.
The water consumption limit is calculated using the formula:
L = K n N i.s.s Q s - E + W pr,
The initial data for calculating water consumption and wastewater disposal limits are as follows:
Q s = 190,000 thousand UAH
N tech = 0.926 m³/thous. UAH
Nsp = 0.283 m³/thous. UAH
N b.h.p. = 0.551 m³/thous. UAH
The consumption limit for fresh drinking water will be:
L n = 1 (0.926 + 0.283 + 0.551) 190000 = 334.4 thousand m 3 /year.
The drainage limit is calculated:
L in \u003d K n N in and.st. s Q s – E in + W in pr,
N in those = 0.573 m³/thous. UAH
N in vsp = 0.220 m³/thous. UAH
N in b.h.p. = 0.437 m³/thous. UAH
N in b.pr. = 174.06 m³/thous. UAH
Lvo = 1 (0.573 + 0.220 + 0.437) 190000 + 174.06 = 407.76 thousand m 3 /year.
LIST OF REFERENCES USED
1. Methodology for determining the balance standards of water supply and water supply at the enterprises of the health transport sector of Ukraine. Kiev 1997.
2. Water Code of Ukraine. Kyiv, 1995
3. Rules for the use of public water supply and sanitation systems in cities and towns of Ukraine. Kyiv, 1994
4. Sewerage of populated areas and industrial enterprises. Designer's Handbook. M:, Stroyizdat, 1987
5. Instructions for rationing water consumption at motor transport enterprises of the Ministry of Motor Transport of the Ukrainian SSR. RD 200 Ukrainian SSR 91-82
6. SNiP 2.04.02-84. Water supply. External networks and structures. Gosstroy USSR.- M.: Stroyizdat, 1984.
7. SNiP 2.04.01-85. Internal water supply and sewerage of buildings. Gosstroy USSR. - M.: CITP Gosstroy USSR, 1985.
8. SNiP 2.04.03-84. Sewerage. External networks and structures. Gosstroy USSR. - M.: CITP Gosstroy USSR, 1984.
9. Steam boilers, vessels and steam pipelines (collection of official materials). "Technique", Kyiv, 1972
10. V.A.Vorobiev, A.G.Komar. Construction Materials. Publishing house of literature on construction. M.:, 1971
11. A.I. Zhukov et al. Sewerage of industrial enterprises. Publishing house of literature on construction. M.:, 1969
13. Scientific and applied reference book on the climate of the USSR. Series 3 Long-term data. Parts 1-6. Vol. 10. Ukrainian SSR. Book 1. L., 1990
14. Hydrosphere. Rules for monitoring the drainage of rain and snow Wastewater from the territories of cities and industrial enterprises /Gosstandart of Ukraine, DSTU 3013-95. - Kyiv, 1995
15. Marzeev A.N., Zhabotinsky V.N., Communal hygiene. M. Medicine, 1979, 576 p.
16. Trakhtman N.N., Izmerov N.F., municipal hygiene. M. Medicine, 1974, 328 p.
Water use refers to the process of consuming water, its source being natural objects or water supply systems.
It is customary to normalize water consumption, that is, to determine its measure established according to the plan. This is done with quality in mind. natural resource. As well as those standards that are approved for the production of a unit of industrial products.
Why is rationing needed?
Its main task is to guarantee such volumes of use in production and in everyday life water resources which will be most effective.
Rationing in the public utilities sector is carried out on the basis of the relevant SNiPs; at industrial enterprises, specially developed guidelines. What exactly is subject to it?
It is customary to standardize the total amount of water consumed during production (per unit), fresh drinking water, as well as technical water. In addition, water that is reused and recycled is taken into account. As well as wastewater, i.e. sewage water (both discharged from the consumer and industrial).
What data does SNiP “Water Consumption Standards” use?
The basis for such rationing is the so-called specific value. What is this water consumption rate? This unit is equal to the maximum permissible water volume accepted according to the plan (with appropriate quality), which is required for the production of a unit of standard product under certain production conditions or for consumption for drinking or economic purposes.
The formation of specific norms is carried out by using their element-by-element components. What is contained in them? Basically we are talking about the specific water consumption for production (for each unit) or for the volume (area) of the enterprise. The same standard of water consumption for an enterprise exists for each separate process, which includes her drinking and household needs.
Another calculated value regulates those losses in the production cycle that are considered irrecoverable. It's about about leakage, evaporation, entrainment, filtration, etc. These are usually classified as factory, industry and inter-industry. It is customary to measure standards in natural units (liters, cubic meters, etc.).
On rationing of water disposal
But experts are interested not only in water consumption rates. It turns out that the exact opposite procedure is also subject to accounting. Water disposal, that is, water discharge, is the process of removing wastewater outside the places where the primary use of the resource occurs (enterprise, settlement). They are removed into natural sources or transferred to specialized organizations for cleaning.
Water disposal standards mean the planned maximum amount of wastewater, also taken per unit of output. In this case, water can belong to one of two degrees of pollution - conditionally (normatively) clean and requiring purification.
Due to the constant improvement of technology, water consumption and wastewater disposal standards are subject to mandatory review after five years. They are calculated directly in production upon approval by management.
How is water quality taken into account?
Requirements for the quality and composition of drinking water in centralized water supply systems are set out on the pages of SanPiN, published in 2001.
Divide by 4 separate categories with its own requirements for each.
I - coolant water for thermal power plants, nuclear power plants, etc. The presence of mechanical impurities, hardness and aggressiveness is excluded. The effluent of such water does not need to be treated, but can be hot.
II - water for washing products, containers, raw materials. Drains can be heavily polluted.
III - raw water (for food products, in the construction industry, etc.).
IV - water for complex use.
Taking into account this division, production technology is selected as rationally as possible while minimizing damage to the environment.
What is a water consumption limit
This is accepted based on the results of the calculation, the basis of which is the water consumption rate, the amount of drinking and technical water for each enterprise in accordance with production conditions, planned losses, and a resource saving program.
The water disposal limit is the amount of consumed wastewater sent to a natural object, taking into account its condition and standard standards.
Both of these limits, calculated and accepted directly at the enterprise, must be approved by the water use agency. They are accepted into general case for a period of a year, but in difficult situations with water resources - monthly or even daily.
Water in municipal services
Providing for the population drinking water- the most important matter of national scale, one of the first responsibilities of the authorities of any locality. In the absence of clean water for drinking, diseases immediately arise - even epidemics. The world is still full of places where access to water of acceptable quality is an unaffordable luxury.
In our country, the Water Code proclaims the priority of public water supply. First of all, regardless of the conditions, the population must be provided clean water. Its supply should not be below 97% (this means that only three days out of a hundred are interruptions in water supply possible).
Of course, this area also has its own water consumption norm. water supply looks like this:
Household and drinking water supply is allocated 56%, public buildings - 17%, industry - 16%. The rest goes to other needs (firefighters - 3%, city - fountains, watering, etc. - 1%, the same amount for all others).
Household water is consumed in the following percentages: for drinking and food purposes (cooking) - 30%, for washing - 10%, for bathing - 30%, for flushing toilet tanks - 30%.
Water consumption standards - daily in a big city
Residents big cities Up to 600 l/day of water is allocated for all domestic and municipal needs. This is the norm of water consumption per person. Its consumption structure looks like this:
For personal needs - 200 l;
To utility companies - 100 l;
To maintain city cleanliness - 100 l;
Local enterprises - 200 l.
The following is typical for municipal water supply.
The quality of water must be exceptionally high in terms of both physical (color, transparency, taste, smell) and chemical (hardness, mineralization, acidity, composition of impurities) properties.
The best water
Quality standards (the first of them in our country dates back to 1937) tend to become stricter from year to year.
What is this connected with? Science does not stand still; every year new facts appear about the effects of certain substances on humans. Accordingly, quality requirements for water composition are subject to revision.
In order for water to meet quality standards, it is subjected to filtration, coagulation (precipitation of impurities), chlorination, removal of unwanted impurities and introduction of desired impurities.
About uneven consumption
Another property of water consumption in the housing and communal services sector is the combination of the relative uniformity of water consumption throughout the year with the unevenness of daily consumption. If the percentage is no more than 15-20, then the difference per day is much greater (we spend about 70% of water in daytime). Therefore, a special unevenness coefficient (hourly and daily) has been developed. Thanks to it, fluctuations in water consumption by hour and month are taken into account, which is required when designing supply systems. After all, their task is to ensure a guaranteed supply even in the mode of maximum water consumption.
