Regulatory and methodological documents are given that regulate the design of systems for the removal and cleaning of surface (rain, melt, watering) Wastewater With residential areas and sites of enterprises, as well as comments on the provisions of SP 32.13330.2012 “Sewerage. External networks and structures” and “Recommendations for the calculation of systems for collecting, diverting and treating surface runoff from residential areas and sites of enterprises and determining the conditions for its release into water bodies” (JSC “NII VODGEO”). These documents allow the disposal of the most polluted part of the surface runoff for treatment in the amount of at least 70% of the annual volume of runoff for residential areas and sites of enterprises that are close to them in terms of pollution, and the entire volume of runoff from the sites of enterprises, the territory of which may be contaminated with specific substances with toxic properties or significant content organic matter. Considered common design practice engineering structures separate and combined sewerage systems that allow short-term discharge of part of the wastewater when intense (rainstorm) rains of rare frequency fall through separation chambers (storm discharges) into a water body. The situations are considered related to the refusals of the territorial departments of the State Expertise and the Federal Agency for Fishery in coordinating the implementation of activities for the designed capital construction facilities on the basis of Article 60 of the Water Code of the Russian Federation, which prohibits the discharge of wastewater into water bodies that have not undergone sanitary treatment and neutralization.

Keywords

List of cited literature

1. Danilov O. L., Kostyuchenko P. A. A practical guide to the selection and development of energy-saving projects. - M., CJSC Tekhnopromstroy, 2006. S. 407–420.
2. Recommendations for the calculation of systems for collecting, diverting and treating surface runoff from residential areas, enterprise sites and determining the conditions for its release into water bodies. Addendum to SP 32.13330.2012 “Sewerage. External networks and structures” (updated version of SNiP 2.04.03-85). - M., OJSC "NII VODGEO", 2014. 89 p.
3. Vereshchagina L. M., Menshutin Yu. A., Shvetsov V. N. On the regulatory framework for the design of systems for the disposal and treatment of surface wastewater: IX scientific and technical conference "Yakovlevsky Readings". – M., MGSU, 2014. S. 166–170.
4. Molokov M. V., Shifrin V. N. Purification of surface runoff from the territories of cities and industrial sites. – M.: Stroyizdat, 1977. 104 p.
5. Alekseev M. I., Kurganov A. M. Organization of diversion of surface (rain and melt) runoff from urban areas. - M .: Publishing house ASV; SPb, SPbGASU, 2000. 352 p.

Introduction
1 area of ​​use
2. Regulatory references
3. Basic terms and definitions
4. General provisions
5. Qualitative characteristics of surface runoff from residential areas and enterprise sites
5.1. Selection of priority indicators of surface runoff pollution during design treatment facilities
5.2. Determination of the calculated concentrations of pollutants during the diversion of surface runoff for treatment and release into water bodies
6. Systems and facilities for diverting surface runoff from residential areas and enterprise sites
6.1. Systems and schemes for the disposal of surface wastewater
6.2. Determination of the estimated costs of rain, melt and drainage water in rainwater collectors
6.3. Determination of the estimated wastewater costs of a semi-separate sewerage system
6.4. Regulation of wastewater flow in the rainwater sewer network
6.5. Surface runoff pumping
7. Estimated volumes of surface wastewater from residential areas and enterprise sites
7.1. Determination of the average annual volumes of surface wastewater
7.2. Definition estimated volumes rainwater discharged for treatment
7.3. Determination of the estimated daily volumes of melt water discharged for treatment
8. Determination of the calculated performance of surface runoff treatment facilities
8.1. Estimated performance of storage type treatment facilities
8.2. Estimated performance of flow-type treatment facilities
9. Conditions for diverting surface runoff from residential areas and enterprise sites
9.1. General provisions
9.2. Determination of standards for permissible discharge (VAT) of substances and microorganisms during the release of surface wastewater into water bodies
10. Wastewater treatment plant
10.1. General provisions
10.2. Selection of the type of treatment facilities according to the principle of water flow control
10.3. Basic technological principles
10.4. Purification of surface runoff from large mechanical impurities and debris
10.5. Separation and regulation of flow in wastewater treatment plants
10.6. Wastewater treatment from heavy mineral impurities (sand trapping)
10.7. Accumulation and preliminary clarification of runoff by static settling
10.8. Reagent treatment of surface runoff
10.9. Cleaning of surface runoff by reagent sedimentation
10.10. Surface runoff treatment with reagent flotation
10.11. Surface runoff treatment by contact filtration
10.12. Post-treatment of surface runoff by filtration
10.13. Adsorption
10.14. Biological treatment
10.15. Ozonation
10.16. Ion exchange
10.17. Baromembrane processes
10.18. Disinfection of surface runoff
10.19. Waste management technological processes surface wastewater treatment
10.20. Basic requirements for the control and automation of technological processes for surface wastewater treatment
Bibliography
Appendix A. Terms and definitions
Appendix B. Meaning of rain intensity values
Appendix B. Parameter values ​​for determining the design flow rates in storm sewers
Annex D. Map of the zoning of the territory Russian Federation along the layer of melt runoff
Annex D. Map of the zoning of the territory of the Russian Federation by coefficient C
Annex E. Methodology for calculating the volume of a reservoir for regulating surface runoff in a storm sewer network
Appendix G. Performance Calculation Methodology pumping stations for pumping surface runoff
Appendix I. Methodology for determining the value of the maximum daily layer of rain debris for residential areas and enterprises of the first group
Appendix K. Methodology for calculating the maximum daily precipitation layer with a given probability of exceeding
Appendix K. Normalized deviations from the mean value of the ordinates of the logarithmically normal distribution curve Ф at different meanings security and asymmetry coefficient
Appendix M. Normalized deviations of the ordinates of the binomial distribution curve Ф for different values ​​of security and asymmetry
Appendix H. Mean daily precipitation layers Hav, coefficients of variation and asymmetry for various territorial regions of the Russian Federation
Appendix P. Methodology and example of calculating the daily volume of melt water discharged for treatment

FEDERAL AGENCY OF THE RUSSIAN FEDERATION FOR
CONSTRUCTION AND HOUSING AND UTILITIES
(ROSSTROY)

Introduction Section 3. General Provisions Section 4. Qualitative characteristics of surface runoff from residential areas and enterprise sites 4.1. Selection of priority indicators of surface runoff pollution in the design of treatment facilities 4.2. Determination of the calculated concentrations of pollutants during the diversion of surface runoff for treatment and release into water bodies Section 5. Quantitative characteristics of surface runoff from residential areas and enterprise sites 5.1. Determination of the average annual volumes of surface wastewater 5.2. Determination of the estimated volumes of surface wastewater when diverting them for treatment 5.3. Determination of the estimated flow rates of rain and melt water in storm sewer collectors 5.4. Determination of the estimated costs of surface runoff when discharged for treatment and into water bodies Section 6. Conditions for diverting surface runoff from residential areas and enterprise sites 6.1. General provisions 6.2. Determination of MPD standards for pollutants when discharging surface wastewater into water bodies Section 7. Systems and facilities for collecting and diverting surface runoff from residential areas and enterprise sites 7.1. Surface runoff collection and diversion schemes 7.2. Structures for regulating surface runoff during discharge for treatment and methods for their calculation 7.3. Surface runoff pumping 7.4. Definition design performance treatment facilities Section 8. Treatment of surface runoff from residential areas and enterprise sites 8.1. General provisions 8.2. mechanical cleaning 8.3. Wastewater treatment by flotation 8.4. Filtration 8.5. Reagent treatment of surface runoff 8.6. Biological treatment 8.7. Ion exchange 8.8. Adsorption 8.9. Ozonation 8.10. Sludge treatment 8.11. Disinfection of surface runoff Legend: BIBLIOGRAPHY Annex 1 Classification of regions of the Russian Federation depending on climatic conditions Annex 2 Values ​​of rain intensity q20 Annex 3 Values ​​of parameters n, mr, γ for determining the estimated flow rates in storm sewer collectors Annex 4 Average duration of rainfall per day with precipitation Appendix 5 Method for plotting the probability distribution function of daily rain layers and an example of calculating the daily rain layer with a given period of a single excess of Р< 1 года Appendix 6 Methodology for calculating the daily layer of precipitation with a given probability of exceeding Appendix 7 Schemes for regulating surface runoff and a methodology for calculating the flow of wastewater discharged for treatment and into water bodies Annex 8 Methodology for calculating the performance of pumping stations for pumping surface runoff

Introduction

3. Rules for the use of public water supply and sewerage systems in the Russian Federation.

The recommendations were developed by a team of specialists from the State Scientific Center of the Russian Federation FSUE "NII VODGEO" under the scientific supervision of a Doctor of Technical Sciences, consisting of: Candidates of Technical Sciences, Doctors of Technical Sciences, Engineers, Candidates of Technical Sciences, Doctors of Technical Sciences.

When developing the Recommendations, the data of field studies obtained by the specialists of the Leningrad Research Institute of Achievements of the Achievements of the Leningrad Region named after V.I. , VNIIVO and a number of industry research organizations at enterprises of various industries, as well as data from the experience of operating surface runoff treatment facilities from urban areas and industrial enterprises, designed and built over the past 30 years.

The recommended calculation of systems for the collection and disposal of surface wastewater is based on the method of limiting intensities, developed and later developed by an engineer, doctor of technical sciences, candidate of technical sciences, doctors of technical sciences and A. M. Kurganov.

The authors express their special gratitude to the chief specialist of the State Unitary Enterprise Soyuzvodokanalproekt, Candidate of Technical Sciences for their assistance in preparing the Recommendations, as well as to the participants of the seminar of the Scientific Research Institute of VODGEO "Systems for collecting, diverting and treating surface runoff from residential areas of cities and industrial enterprises" (April 6-7, 2005 Moscow) dedicated to new edition Recommendations, for the comments and suggestions.

1 With the release of these recommendations "Temporary recommendations for the design of facilities for the treatment of surface runoff from the territories of industrial enterprises and the calculation of the conditions for its release into water bodies", published by VNII VODGEO in 1983, become invalid.

Section 1 Legislative and Regulatory Documents

1. Water Code of the Russian Federation of November 16, 1995 .

3. Rules of protection surface water. - M., 1991.

4. SanPiN 2.1.5.980-00. Hygienic requirements for the protection of surface waters.

5. GOST 17.1.3.13-86. General requirements to the protection of surface waters from pollution.

6. Rules for the use of public water supply and sewerage systems in the Russian Federation. Approved by Decree of the Government of the Russian Federation of February 12, 1999 No. 000.

7. SNiP 2.04.03-85. Sewerage. External networks and structures.

8. SNiP 23-01-99. Building climatology.

9. GOST 17.1.1.01-77. Protection of Nature. Hydrosphere. Use and protection of waters. Basic terms and definitions.

10. GOST 17.1.3.13-86. Protection of Nature. Hydrosphere. Classification of water bodies.

11. SanPiN 2.2.1/2.1.1.1200-03. Sanitary and epidemiological rules and regulations.

12. GOST 27065-86. Water quality. Terms and Definitions.

13. GOST 19179-73. Land hydrology. Terms and Definitions.

14. List of fishery standards: maximum allowable concentrations (MAC) and indicative safe exposure levels (SLI) harmful substances for water of water bodies having a fishery purpose. Approved by order of Roskomrybolovstvo dated June 28, 1999 No. 96.

15. GN 2.1.5.1315-03. Maximum Permissible Concentrations (MPC) of chemicals in the water of water bodies for drinking and domestic water use. Hygienic standards. Approved and put into effect by the Decree of the Chief State Sanitary Doctor of the Russian Federation dated April 30, 2003 No. 78.

16. GN 2.1.5.1316-03. Approximately acceptable levels(ODU) of chemicals in the water of water bodies for drinking and domestic water use. Hygienic standards. Approved and put into effect by the Decree of the Chief State Sanitary Doctor of the Russian Federation dated 01.01.01 No. 78.

Section 2. Terms and definitions

For the purposes of this document, the following terms and definitions apply:

STORAGE CAPACITY(surface runoff accumulator) - a facility for receiving, collecting and averaging the flow rate and composition of surface wastewater from residential areas and enterprise sites for the purpose of their subsequent treatment.

Today we will analyze how to make a hydraulic calculation of the heating system. Indeed, to this day, the practice of designing heating systems on a whim is spreading. This is a fundamentally wrong approach: without preliminary calculation we raise the bar on material consumption, provoke abnormal modes of operation and lose the opportunity to achieve maximum efficiency.

Goals and objectives of hydraulic calculation

From an engineering point of view, a liquid heating system seems to be a rather complex complex, including devices for generating heat, transporting it and releasing it in heated rooms. Ideal mode of operation hydraulic system heating is considered to be one in which the coolant absorbs the maximum heat from the source and transfers it to the room atmosphere without loss during movement. Of course, such a task seems completely unattainable, but a more thoughtful approach allows us to predict the behavior of the system in various conditions and get as close to benchmarks as possible. This is the main goal of designing heating systems, the most important part of which is considered to be hydraulic calculation.

Practical Goals hydraulic calculation are:

1. To understand at what speed and in what volume the coolant moves in each node of the system.
2. Determine the impact that a change in the operating mode of each of the devices has on the entire complex as a whole.
3. Determine what performance and performance characteristics of individual components and devices will be sufficient for the heating system to perform its functions without a significant increase in cost and providing an unreasonably high safety margin.
4. Ultimately, it is necessary to ensure a strictly metered distribution of thermal energy over various heating zones and ensure that this distribution will be maintained with a high constancy.

You can say more: without at least basic calculations it is impossible to achieve acceptable stability and long-term use of equipment. Modeling the operation of a hydraulic system, in fact, is the basis on which all further design development is built.

Types of heating systems

The tasks of engineering calculations of this kind are complicated by the high diversity of heating systems, both in terms of scale and configuration. There are several types of heating interchanges, each of which has its own laws:

1. Two-pipe dead-end systems a - the most common version of the device, well suited for organizing both central and individual heating circuits.

The transition from heat engineering to hydraulic calculation is carried out by introducing the concept of mass flow, that is, a certain mass of coolant supplied to each section of the heating circuit. Mass flow is the ratio of the required heat output to the product of the specific heat capacity of the coolant and the temperature difference in the supply and return pipelines. So in the sketch heating system note the key points for which the nominal mass flow is indicated. For convenience, the volumetric flow is also determined in parallel, taking into account the density of the heat carrier used.

G \u003d Q / (c (t 2 - t 1))

• Q - required thermal power, W
• c - specific heat capacity of the coolant, for water accepted 4200 J / (kg ° С)
• ΔT \u003d (t 2 - t 1) - temperature difference between supply and return, ° С

The logic here is simple: to deliver required amount heat to the radiator, you must first determine the volume or mass of the coolant with a given heat capacity passing through the pipeline per unit time. To do this, it is required to determine the speed of movement of the coolant in the circuit, which is equal to the ratio of the volumetric flow to the cross-sectional area of ​​the internal passage of the pipe. If the velocity is calculated relative to the mass flow, the value of the coolant density must be added to the denominator:

V = G/(ρ f)

• V is the speed of the coolant, m/s
• G - coolant flow rate, kg / s
• ρ is the density of the coolant, for water you can take 1000 kg / m 3
• f is the cross-sectional area of ​​the pipe, is found by the formula π- r 2, where r is the inner diameter of the pipe, divided by two

Flow and speed data are needed to determine the nominal diameter of the decoupling pipes, as well as the flow and pressure circulation pumps. Devices forced circulation should create overpressure, which allows to overcome the hydrodynamic resistance of pipes and shut-off and control valves. The greatest difficulty is the hydraulic calculation of systems with natural (gravitational) circulation, for which the required overpressure is calculated from the rate and degree of volumetric expansion of the heated coolant.

Head and pressure losses

Calculation of parameters according to the relations described above would be sufficient for ideal models. AT real life both the volumetric flow and the coolant velocity will always differ from those calculated at different points in the system. The reason for this is the hydrodynamic resistance to the movement of the coolant. It is due to a number of factors:

1. The forces of friction of the coolant against the walls of the pipes.
2. Local resistance to flow formed by fittings, taps, filters, thermostatic valves and other fittings.
3. The presence of branches of connecting and branching types.
4. Turbulent swirls on turns, constrictions, expansions, etc.

The task of finding the pressure drop and velocity in different parts of the system is rightfully considered the most difficult, it lies in the field of calculations of hydrodynamic media. Thus, the forces of fluid friction on the inner surfaces of the pipe are described by a logarithmic function that takes into account the roughness of the material and the kinematic viscosity. Calculating turbulent eddies is even more difficult: the slightest change in the profile and shape of the channel makes each individual situation unique. To facilitate the calculations, two reference coefficients are introduced:

1. Kvs- characterizing the throughput of pipes, radiators, separators and other areas close to linear.
2. K ms- determining local resistance in various fittings.

These coefficients are indicated by the manufacturers of pipes, valves, taps, filters for each individual product. Using the coefficients is quite easy: to determine the pressure loss, Kms is multiplied by the ratio of the square of the coolant velocity to the double value of the acceleration free fall:

Δh ms = K ms (V 2 /2g) or Δp ms = K ms (ρV 2 /2)

• Δh ms - pressure loss at local resistances, m
• Δp ms - pressure loss at local resistances, Pa
• K ms - coefficient local resistance
• g - free fall acceleration, 9.8 m/s 2
• ρ is the density of the coolant, for water 1000 kg / m 3

The pressure loss in the linear sections is the ratio of the channel capacity to the known capacity factor, and the result of the division must be raised to the second power:

P \u003d (G / Kvs) 2

• P - head loss, bar
• G - the actual flow rate of the coolant, m 3 / hour
• Kvs - throughput, m 3 / hour

System pre-balancing

The most important final goal of the hydraulic calculation of the heating system is the calculation of such throughput values ​​at which a strictly metered amount of coolant with certain temperature, which ensures the normalized release of heat on heating devices. This task seems difficult at first glance. In reality, balancing is performed by control valves that restrict the flow. For each valve model, both the Kvs coefficient for the fully open state and the Kv coefficient change graph for different degrees of opening of the adjusting stem are indicated. By changing the capacity of the valves, which are usually installed at the connection points heating appliances, it is possible to achieve the desired distribution of the coolant, and hence the amount of heat transferred by it.

There is, however, a small nuance: when the throughput at one point of the system changes, not only the actual flow in the section under consideration changes. Due to a decrease or increase in flow, the balance in all other circuits changes to some extent. If we take for example two radiators with different thermal power, connected in parallel with the oncoming movement of the coolant, then with an increase in the throughput of the device that is the first in the circuit, the second one will receive less coolant due to an increase in the difference in hydrodynamic resistance. On the contrary, when the flow is reduced due to the control valve, all other radiators further down the chain will receive a larger volume of coolant automatically and will need additional calibration. Each type of wiring has its own balancing principles.

Software complexes for calculations

Obviously, manual calculations are justified only for small heating systems with a maximum of one or two circuits with 4-5 radiators in each. More complex systems heating with a thermal power of over 30 kW require an integrated approach to the calculation of hydraulics, which expands the range of tools used far beyond the limits of a pencil and a sheet of paper.

Today there are enough a large number of software provided the largest manufacturers heating technology such as Valtec, Danfoss or Herz. In such software systems for calculating the behavior of hydraulics, the same methodology is used, which was described in our review. First, an exact copy of the designed heating system is modeled in the visual editor, for which data on the heat output, type of coolant, length and height of pipeline drops, fittings used, radiators and underfloor heating coils are indicated. The program library contains a wide range of hydraulic devices and fittings, for each product the manufacturer has determined in advance the operating parameters and basic coefficients. If desired, third-party device samples can be added if the required list of characteristics is known for them.

At the end of the work, the program makes it possible to determine the appropriate conditional pass pipes, select sufficient flow and pressure of circulation pumps. The calculation is completed by balancing the system, while during the simulation of the operation of hydraulics, the dependences and the influence of changes in the throughput of one node of the system on all the others are taken into account. Practice shows that the development and use of even paid software products is cheaper than if the calculations were entrusted to contract specialists.