It is unlawful to impose on enterprises that discharge wastewater into the city sewerage system the obligation to keep records of wastewater in the manner prescribed for water users.
Maintaining, in accordance with the established procedure, records of the volume of discharge of waste and (or) drainage waters, their quality, as well as providing the results of such records to the federal executive body authorized by the Government of the Russian Federation is one of the responsibilities of the owners of water bodies and water users, provided for in clause 5, part 2, art. . 39 of the Water Code of the Russian Federation.
Keeping records of the volume of waste and (or) drainage water discharges and their quality by owners of water bodies and water users is carried out in the manner determined by the Ministry of Natural Resources of Russia; accounting results are provided to Rosvodresursy (clause 16 of the Regulations on the implementation of state monitoring of water bodies).
In pursuance of this norm, the Order of the Ministry of Natural Resources of Russia dated July 8, 2009 No. 205 approved the Procedure.
The obligation to keep records of the discharge of waste and (or) drainage water, their quality in accordance with clause 2 of the Procedure is assigned to individuals or legal entities who are granted the right to use a water body for the purpose of discharge.
In this case, water users are understood as persons who are granted the right to use a water body (Article 1 of the Water Code of the Russian Federation).
The right to use a water body for discharge Wastewater provided by interested parties receiving a decision to provide a water body for use (Clause 2, Part 2, Article 11 of the Water Code of the Russian Federation) or on the basis of a water use license issued before 01/01/2007 and an agreement concluded in accordance with it (Part 1, Art. 5 of the Federal Law “On the entry into force of the Water Code Russian Federation» ).
In addition, in order to discharge wastewater into a water body, the water user must develop a VAT, subject to approval by Rosvodresursy in agreement with the authorized federal executive authorities, and also obtain permits for discharge.
At the same time, clause 10 of the Procedure states that the composition and properties of discharged wastewater and (or) drainage water are determined separately at each release into water bodies, as well as at the points where wastewater is transferred to the sewerage system(forms 2.1, 2.2 appendices to the Order).
Form 2.2 “Logbook for recording the quality of discharged wastewater and (or) drainage water” is to be used by all water users who discharge wastewater and (or) drainage water, as well as transfer water to the city sewerage system in accordance with clause 2 of the notes to this form, approved in the appendix to Order.
From these norms of the Procedure it follows that, provided for by the Water Code of the Russian Federation, the Regulations on the implementation of state monitoring of water bodies, the obligation of water users to keep records of wastewater is extended to persons who do not discharge wastewater directly into a water body, but transfer it to the city sewerage system.
In addition, in accordance with paragraph 4 of the notes to form 2.2, the logbook for recording the quality of discharged wastewater and (or) drainage water is filled out based on the results of water analysis in accordance with the agreed program specified in clause 13 of the Procedure. According to this paragraph, the program for measuring the quality of waste and (or) drainage waters (frequency, sampling location, volume and list of ingredients to be determined) is agreed upon by the territorial body of Rosvodresursy within 30 days.
Consequently, mandatory wastewater accounting in accordance with the Procedure entails for persons transferring wastewater to the city sewerage system the need to coordinate the accounting program with Rosvodresursy and provide accounting results to Rosvodresursy.
At the same time, it should be noted that relations regarding the use of public sewerage systems for the discharge of industrial wastewater are regulated by the relevant Rules.
An agreement is concluded between the person discharging wastewater into the city sewer system (subscriber) and the water and wastewater services organization, which also provides for the subscriber to keep records of discharged wastewater (clause 13 of the Rules).
In this case, the procedure for carrying out this accounting is regulated by a special section of the Rules (Section IV). In addition, the subscriber is obliged to monitor the composition and properties of wastewater discharged into the sewerage system, including wastewater from sub-subscribers, and provide the water and wastewater services organization with information on the results of such control (clause 88 of the Rules).
Thus, the obligation for the subscriber to account for wastewater transferred to the city sewerage system is provided for by current legislation, but in the manner determined by the Rules, with the provision of a report to the water and wastewater services organization.
Another condition of the agreement between the subscriber and the water and wastewater services organization is the establishment of regulatory requirements for the subscriber on the composition of wastewater.
It should be noted that regulatory requirements for the composition of wastewater are integral part sewerage standards, which are established by local governments and ensure the normal functioning of sewerage systems. Water disposal standards are established for the subscriber taking into account the conditions of compliance with the norms of maximum permissible discharges of wastewater into water bodies, approved for water and wastewater organizations by environmental authorities (clause 1 and clause 61 of the Rules).
Thus, when discharging wastewater into the city sewerage system, the subscriber is not a water user - the water user is the water and wastewater services organization, which sets VAT and issues a decision to provide a water body for use, as well as a discharge permit.
In this regard, the extension in clause 10 of the Procedure, in clause 2 of form 2.2 of the appendix to the Procedure of the obligations of water users for keeping records of wastewater to persons who are not water users (transferring wastewater to the city sewerage system), is unlawful and contradicts the Water Code of the Russian Federation, and also the Regulations on the implementation of state monitoring of water bodies, the Rules, clause 2 of the Procedure.
It should be noted that if a normative legal act contradicts acts of greater legal force, the court, including the arbitration court, makes a decision in accordance with the latter (part 2 of article 11 of the Civil Procedure Code of the Russian Federation, part 2 of article 13 of the Arbitration Procedural Code RF).
Thus, clause 10 of the Procedure, clause 2 of form 2.2 of the appendix to the Procedure, in the part that provides for the obligation to keep records of wastewater by persons transferring wastewater to the city sewerage system, should not be applied.
In addition, the specified provisions of the Procedure can be declared invalid as they contradict higher legislative acts by persons whose rights are violated by these norms, by challenging them in the Supreme Court of the Russian Federation in the manner prescribed by Chapter. 24 of the Civil Procedure Code of the Russian Federation.
Normative legal acts
1. Water Code of the Russian Federation dated June 3, 2006 No. 74-FZ.
2. Regulations on the implementation of state monitoring of water bodies, approved
Decree of the Government of the Russian Federation dated April 10, 2007 No. 219.
3. The procedure for keeping volume records by owners of water bodies and water users
fence (seizure) water resources from water bodies and the volume of wastewater discharge
and (or) drainage waters, their quality, approved by order of the Ministry of Natural Resources of Russia
dated 07/08/2009 No. 205.
4. Federal Law dated June 3, 2006 No. 73-FZ “On the introduction into force of the Water Code of the Russian
Federation".
5. Rules for using public water supply and sewerage systems in the Russian Federation
The subscriber wants to oblige the water and waste management organization to recalculate in connection with the supply cold water poor quality
The water utility organization wants to collect payment for cold water consumed in the absence of an agreement
The water utility organization wants to collect debt for unaccounted for cold water consumed
The subscriber has not paid the fee accrued to him for sewerage services in relation to general house needs, for which charging is not allowed, and wants to oblige the water and wastewater services organization to recalculate
The subscriber wants to oblige the water and waste management organization to recalculate the payment for supplied cold water, since the water and waste management organization incorrectly determined its volume
1. The following quantities are subject to commercial accounting:
1) water supplied (received) for a certain period to subscribers under water supply contracts;
2) water transported by the organization operating water supply networks under a water transportation agreement;
3) water for which water treatment measures have been carried out under a water treatment agreement;
4) wastewater received from subscribers under water disposal contracts;
5) wastewater transported by an organization transporting wastewater under a wastewater transportation agreement;
6) wastewater that has been treated in accordance with the wastewater treatment agreement.
2. Commercial accounting of water and wastewater is carried out in accordance with the rules for organizing commercial accounting of water and wastewater, approved by the Government of the Russian Federation.
3. Commercial accounting of thermal energy that is supplied (received) for a certain period to subscribers in the hot water under hot water supply contracts, is carried out in accordance with the Federal Law “On Heat Supply”.
4. Commercial metering is carried out at metering stations by measuring the amount of water and wastewater using water and wastewater metering devices or, in the cases provided for in this article, by calculation method.
5. Water and wastewater metering devices are placed by the subscriber, the organization operating the water supply or sewer networks, at the border of the balance sheet ownership of the networks, the border of the operational responsibility of the subscriber, the specified organizations or in another place in accordance with the agreements specified in Part 1 of Article 7, Part 1 of Article 11, Part 5 of Article 12 of this Federal Law, connection agreements (technological connection) . Water and wastewater metering devices installed to determine the amount of water supplied to the subscriber under a water supply agreement, wastewater discharged by the subscriber under a water disposal agreement, are sealed by organizations that provide hot water supply, cold water supply and (or) wastewater disposal and with which the specified agreements have been concluded, without charging fees from the subscriber, except for cases when the sealing of the relevant metering devices is carried out by such an organization again due to the violation of the seal due to the fault of the subscriber or third parties.
(see text in the previous edition)
6. Connection (technological connection) of subscribers to a centralized hot water supply system, centralized cold water supply system without equipping a metering unit with water metering devices is not allowed.
(see text in the previous edition)
7. Subscribers and organizations operating sewer networks are required to equip their sewer outlets into the centralized drainage system with wastewater metering devices in cases determined by the rules of cold water supply and wastewater disposal approved by the Government of the Russian Federation.
8. Installation, replacement, operation, verification of water and wastewater meters are carried out in accordance with the legislation of the Russian Federation.
9. Subscribers, organizations operating water supply and sewerage networks are obliged to provide access to representatives of the organization providing hot water supply, cold water supply and (or) wastewater disposal, with which the agreements specified in
11. If the subscriber does not have a wastewater meter, the volume of wastewater discharged by the subscriber is assumed to be equal to the volume of water supplied to this subscriber from all sources centralized water supply, this takes into account the volume of surface wastewater if the reception of such wastewater into the drainage system is provided for in the drainage agreement.
The organization of commercial accounting of wastewater at pumping stations of settlements and enterprises is becoming increasingly important. When designing wastewater metering units, it is necessary to analyze the design, technological and operational conditions of a specific pumping station and know the operating features of flow meters various types. RANET ENERGO LLC is a company that has already achieved success in this difficult matter.
LLC "RANET ENERGO", Korolev
LLC "RANET ENERGO" was created in 1990 and is located in the town of Korolev near Moscow. Areas of activity of the enterprise: energy saving, ecology and automation. A distinctive feature of the company since its inception has been the performance of work at remote sites throughout the country. RANET ENERGO LLC was the first in the country to install metering devices on non-pressure pipelines and open channels. In total, more than 420 metering units for wastewater, storm water, and circulation water on non-pressure pipelines and open canals have been designed and implemented. The company has designed water monitoring stations at industrial wastewater outlets industrial enterprises. The station includes a wastewater flow meter, automatic analyzers of oil products in water, pH and temperature values.
Rice. 1. Scheme water balance enterprises
The company has successfully organized commercial water metering at many facilities. Electromagnetic (EM) and ultrasonic (US) flow meters from different manufacturers are used as metering devices. Depending on the operating conditions, full-bore EM and ultrasonic flowmeters are used; Ultrasonic flowmeters with embedded primary transducers (PP) and ultrasonic flowmeters with overhead PP. The main tasks when designing metering units for pumping stations(NS) – organize straight-line measuring sections inside the PS building. In cases where this cannot be achieved, measuring chambers are built outside the NS.
An analysis of the enterprise water balance diagram (Fig. 1) shows that an integral part of the task of integrated energy accounting, along with taking into account thermal energy and coolant, cold water, is the organization of commercial accounting of waste and storm water in free-flow pipelines and at sewerage pumping stations (SPS).
Some general issues problems that arise when creating wastewater accounting systems, and the features of wastewater accounting in non-pressure pipelines, were discussed earlier in.
This material is devoted to the design features of wastewater metering units at water pumping stations.
Most of the previously built and currently under construction pumping stations are not equipped with wastewater metering units. Meanwhile, the organization of commercial accounting of wastewater at the pumping stations of settlements, enterprises, and cottage settlements is becoming increasingly important.
When organizing commercial accounting of wastewater at the design stage of metering units, it is necessary to resolve two main issues:
Select installation locations for metering devices (flow meters);
Select the type of metering devices.
There are no standard solutions for wastewater metering units at water pumping stations, since water pumping stations differ quite significantly from each other in architecture and layout technological equipment, location and diameters of pipelines and shut-off valves; type, number and performance of pumping units, etc.
Therefore, when conducting a pre-design survey of a pumping station, the totality of all initial data on the technical characteristics and location of process equipment, and operational features are analyzed. To select the type of flow meters and their installation locations, it is necessary to know the types and performance of pumps, the operating time of the pump after switching on (duration of pumping out the receiving tank).
Metering units must be installed on the outlet pipelines (outlets) of the pumping station.
However, at many pump stations it is impossible to place measuring sections of pipelines with flow meters inside the pump station building. In these cases, special measuring chambers are built outside the KNS building.
The larger the diameters of the pipelines, the more difficult it is to place measuring sections in the pumping station building without significant reinstallation of pipelines and shut-off valves.
Low-capacity pumping stations have other problems.
Nowadays, pumping stations are being built in which all the equipment is located underground. Submersible pumps are used; there is no machine room or heated pavilion. At such pump stations, the measuring sections may be partially below the water level in the receiving tank, and the flow meters may be installed directly above or below the water.
Typically, a pumping station has one or two outlets (working and backup), on which metering devices are installed.
Rice. Primary transducers of ultrasonic correlation flowmeters installed on existing pipelines without dismantling them
But it doesn't always work out that way. For example, at the industrial storm sewer pumping station of one of the Moscow region enterprises there is one outlet - a collector with a diameter of DN 600 mm. There are five pumping units of different capacities installed in the machine room, which are connected to the manifold by pipelines with a diameter of DN from 150 to 250 mm.
The customer was offered two options for implementing commercial wastewater metering:
The measuring section is installed in the machine room parallel to the existing manifold DN 600 mm;
A measuring chamber is being built outside the KNS building.
Both options were rejected by the customer due to the complexity of implementation (cramped conditions and large volume installation work in the engine room, wetland).
Then the project implemented the third option, which was optimal for this case. Flow meters of the electromagnetic type, since the lengths of the measuring sections are limited, are installed in vertical sections after each of the five pumps. Wastewater accounting is carried out by summing the readings of all flow meters.
The necessary conditions for the correct operation of most types of flow meters are: water supply at the measuring sections with a full cross-section, the absence of a gas phase (air) in the measured liquid, and the absence of counterflow at the measuring sections.
Rice. Installation of clamp-on ultrasonic flow meter sensors
For pumping stations, all these conditions are of particular importance, since pumps operate in start-stop mode and problems with the formation of air bubbles, water-air mixture, and reverse flow of water arise quite often.
Now about the types of flow meters used to account for wastewater at a pumping station.
Electromagnetic and ultrasonic flowmeters with surface-mounted or mortise sensors, as well as ultrasonic correlation ones, can be used at SPS. In our opinion, tachometer and vortex flowmeters should not be used for wastewater metering.
Among the advantages of electromagnetic flowmeters in relation to the conditions of pumping stations, there remains, perhaps, only one thing - short measuring sections.
The wide measurement range of electromagnetic devices in this case, as a rule, does not matter.
But there are exceptions. Sometimes it is necessary to provide flow measurements over a very wide range. This happens in cases where frequency converters (FCs) are used that are capable of changing the water flow at the outlet of the SPS in a wide range.
For example, we installed ultrasonic correlation flowmeters on two DN 500 pipelines of one of the Moscow pumping stations. After several months of successful operation of the metering units, we received a signal that the flow meters were malfunctioning during operation - periodically zero flow readings appeared on their displays while the pumps were running. Studying the situation made it possible to find the reason for the “failure” of the metering devices. It turns out that after the commissioning of metering units at the pumping station, emergency situations were installed, which, under certain operating modes of the pumping station, created a flow rate in the pipes below the minimum measured flow rate of 45 m3/hour.
Therefore, further adjustment of wastewater accounting at the pumping station was carried out by appropriately adjusting the frequency converter system.
In addition, if there are frequency converters at the SPS, it is necessary to pay attention to the fact that emergency situations can create powerful interference that can disrupt the operation of metering devices.
It is also impractical to use full-bore electromagnetic flowmeters on pipelines with a diameter of over 200–300 mm due to the high cost of such devices.
Therefore, our company more often uses ultrasonic flow meters in projects of wastewater metering units at sewage pumping stations.
Ultrasonic flowmeters can be installed on pipes of almost any diameter.
Where possible and appropriate, ultrasonic transducers are inserted into existing pipelines without dismantling them. In this case, existing pipes are used as measuring sections, which is certainly an important advantage of the ultrasonic measurement method.
Another significant advantage of ultrasonic devices is the ability to verify them using a simulation method without dismantling the primary transducers and without spilling.
It can be argued that the implementation of the last two advantages of ultrasonic flow meters inevitably leads to a decrease in the accuracy characteristics of metering units. And indeed it is. However, such stringent requirements are not imposed on water metering units (for example, there are no restrictions on the error of metering devices) as on thermal energy and coolant metering units.
Therefore, both the insertion of ultrasonic transducers into existing pipes and the use of flow meters with clamp-on sensors when metering wastewater, in our opinion, are justified and appropriate.
Customers are especially attracted to flow meters with clamp-on sensors due to the minimal costs of their installation, which, of course, is an absolute advantage over flow meters with embedded sensors. It is convenient to install flow meters with clamp-on sensors on plastic pipelines.
However, flow meters with clamp-on sensors also have their drawbacks.
Firstly, even if you use flow meters with clamp-on sensors, it is not always possible to do without rewiring the pipelines, because in any case, it is necessary to organize measuring sections of certain lengths and diameters.
Secondly, during operation of flowmeters of these types, adjustment and maintenance are often required.
And most importantly, the reliability of the readings of such flow meters depends on the professionalism of the adjuster, and representatives of the operating or controlling organizations often do not have sufficient technical training to check whether the flow meter has been adjusted correctly.
It should be noted that from the accepted design solutions The cost of organizing wastewater accounting depends on the cost. Moreover, the cost of implementing different solutions can differ significantly.
Thus, when designing wastewater metering units at a pumping station, it is necessary to analyze the design, technological and operational conditions of a specific pumping station, as well as knowledge of the operating features of flow meters of various types and manufacturers.
Literature
Popov A.G. Commercial accounting of wastewater - problems and features. "EnergoSovet" energy saving portal
A.G. Popov, Ph.D., director
LLC "RANET ENERGO", Korolev,
Providing residential development with utilities is important aspect increasing the comfort of living. Living in an individual house is characterized by high water consumption for household needs without subsequent disposal: watering the garden, water consumption by people and animals, etc. In order not to pay for sewerage services for consumed water, the installation of wastewater meters is required. The meter will show that much of it actually goes down the drain. less water than what comes into the house.
The wastewater flow meter is a high-tech device that has electronic components in its design and ensures accurate and reliable measurements. The design of the instrument base and components of the device allows you to work in chemically aggressive environments, without losing the reliability and accuracy of the measurements.
How they work
Sewage meters are divided into the following types depending on the operating principle underlying their operation:
- ultrasonic;
- electromagnetic;
- lever-pendulum.
According to the measurement method, wastewater metering devices are divided into two types:
- Accounting for the level of waste flow in a pipe. The number of drains is determined depending on the size of the channel.
- Taking into account the flow rate together with the level of waste flow in the pipe. The number of drains is determined according to the “area-velocity” principle.
Ultrasonic meters
High-precision instruments designed to measure the amount of liquid sewage. Measurements are made using area-velocity sensors, which are easily installed in the collector. They are used in open channels, gravity systems, non-pressure pipelines, and in the industrial field for commercial accounting. When equipment is equipped with hydrostatic sensors, in addition to monitoring discharge volumes, the filling of the sewer network is monitored.
Installation is carried out inside the pipeline or channels without additional construction work.
The operation of ultrasonic sensors is based on measuring the difference in the travel time of ultrasonic vibration pulses in the direction of fluid flow and against it. Sensors (piezoelectric transducers) are installed at the measuring section, which initiate the excitation of these pulses.
The ultrasonic sensor is installed at an angle relative to the flow cross-section. Velocity can be measured using one or two beams of ultrasonic vibrations. The sensors work alternately, first as an emitter, then as a receiver. The movement of the fluid causes a change in the time of complete propagation of signals along and against the flow. Based on the received signals, the speed and volume of wastewater in the pipeline is determined.
The advantages of devices of this type lie in their versatility, the ability to be installed in pipelines of any geometry with a diameter of up to 9 m. Measurements take place in any direction of flow. The construction of additional wells or measuring chambers is not required to install the device.
The disadvantages of the devices include the need to constantly clean the sensors. The heterogeneity of the effluent, the presence of bubbles, and suspended matter reduce the reliability of the indicators. The measurement error reaches 5%.
Electromagnetic principle
These are simple but reliable instruments for measuring the volume of wastewater, including untreated wastewater. Used on gravity and pressure sewer systems, provided that the pressure in the pressure drains does not exceed 40 bar.
The operating principle of wastewater volume meters is based on measuring the electromotive force (EMF) that occurs in wastewater when passing through an artificial magnetic field. The fluid flow rate is directly proportional to the emerging EMF, which is converted into a signal sent to the display of the controller device. Measuring wastewater volumes is only possible if they carry out electricity, since the operation of the devices is based on Faraday’s law (magnetic induction). The liquid that passes through the magnetic field acts as a moving core. It initiates an electric current depending on the speed of movement of the wastewater.
The advantage of electromagnetic devices is their versatility; they allow you to measure any type of liquid waste that conducts electric current, including untreated waste. The devices consistently show high-precision data provided that they have a self-cleaning system for the electrodes.
Note! The disadvantages include unstable operation in the presence of strong electromagnetic interference. The cost of flow meters depends on the diameter of the pipe or channel, since the design of the primary converter must always be full bore.
Lever-pendulum wastewater meters
The scope of application of the devices is non-pressure open and closed sewer channels. The operating principle is to measure the level and average flow rate. Measurements are carried out continuously. The dimensions of the channel and information about the current value of the flow level make it possible to calculate the current value of the cross-sectional area of the wastewater. The volume of wastewater is determined as the product of the flow rate of passing sewage per unit of measurement time. The performance of the device is defined as the product of the flow cross section and its speed.
The device is a device with a lever mounted on an axis, to which a spherical float is rigidly attached. At the other end of the lever there is a sensor for the angle of deflection of the lever relative to the vertical to the horizontal line. If there are no drains, the lever is in a vertical position. If there is drainage, the float rises or falls, changing the angle of inclination depending on the level of drainage in the pipe. The level of sewage is determined by reading the angle of inclination.
To measure speed, another unit is used, which is a rotating blade made of stainless steel. The blade is fixed to the axis. One end of the blade drops freely into the liquid waste. A sensor is attached to the axis, which shows the flow speed based on the angle of deflection of the blade depending on the strength of the current.
These devices provide high accuracy of the measured parameters of wastewater metering, regardless of the presence of contaminants in the pipe and other factors.
Before choosing a flow meter model, you need to know what requirements apply to the sewerage system and what type of water pipelines are used.
Sewage networks can be divided into open and closed. Closed networks are divided into pressure and non-pressure. Non-pressure channels also include open channels. In pressure channels, wastewater moves under the influence of pumps; in non-pressure and open channels, it moves by gravity due to the inclination of the pipeline.
For measurements in pressure pipelines, instruments with sensors are used. Electromagnetic or ultrasonic flow meters are selected based on the estimated waste flow rates.
Establishing wastewater metering in gravity pipelines is a more difficult task. Open or closed channels are characterized by the movement of sewage by gravity under the influence of gravity at low speed.
Instruments that measure only the liquid level provide readings for further calculation of waste volumes, taking into account the channel cross-section data. For open channels, lever-pendulum flowmeters are used.
More accurate results are provided by devices of the second type, measuring according to the “area-velocity” principle. The liquid level in free-flow channels does not have a constant value. In a private house, drainage can occur periodically, where the drainage will be unloaded most of the time, so data on the flow area and its speed over a period of time is used.
Ultrasonic and electromagnetic flowmeters are used to measure velocity in non-pressure closed channels. Specific models are selected depending on the diameter of the pipeline.
Wastewater metering unit
A wastewater metering unit is a set of means for measuring wastewater flow rates, a well, for placing metering devices and their Maintenance, and the section of pipe on which measurements are taken. Measuring instruments consist of a primary transducer (sensor) and a secondary transducer, in which the measured information is processed, stored and displayed. The well is constructed specifically on this section of the pipeline. The pipeline must be straight in the drainage measurement section.
Before choosing the type of flow meter, it is necessary to assess the need and feasibility of installing a metering device and select a location for installing the device.
When installing a metering station in an individual building, the location should be selected before the connection point with the public sewer system.
When choosing measuring instruments, the device must record wastewater flow rates over the entire flow range for the existing pipeline diameter. The measurement accuracy must be high, an error of no more than 5% is allowed. The accounting system must accumulate all information, provide information about the total accumulative volume, periods of measurements and downtime. The power supply to the flowmeter must be uninterrupted with a backup power supply.
The section of the pipeline where the meter is installed must be straight. The flow meter should be located at the very bottom of the individual sewer network, where the maximum filling of the pipeline is located.
Each node requires a project, which is coordinated with departments and organizations servicing sewer networks. After receiving all permits and completing the project, a subscription service agreement is concluded.
Video
Ultrasonic wastewater flow meter in action:
Down the drain every day settlements tons of wastewater are drained - water polluted by industrial, household waste, precipitation.
Sewage is removed through a complex of equipment and structures. At the same time, the liquid is purified. To ensure the processing of liquid waste, enterprises carry out wastewater accounting.
Energy conservation is an important aspect of the company's work. It helps reduce energy consumption, conserve natural resources, and increase net profit.
Organizations can use installations to control the volume of liquid waste discharge (drainage water). Accounting is carried out using measuring instruments installed on the pipeline of existing underground communications.
Complexes of structures for draining wastewater are not always suitable for installing meters due to their dilapidation, so the pipeline is being modernized. Reconstruction is required in cases not related to the age of communications:
- it is impossible to access the pipes due to their location (under a building, road, embankment);
- ground sediments in the system;
- the slope is less than the required level;
- the pipeline design does not include straight sections;
- back-up from the city collector;
- relatively small amount of waste.
In addition to the fact that enterprises install meters, services that control the supply and removal of liquid additionally control the amount of liquid waste.
Commercial accounting of water and wastewater by enterprises is carried out in accordance with Federal Law No. 416 of December 7, 2011, and Decree of the Government of the Russian Federation No. 776 of September 4, 2013.
Why are wastewater meters installed?
Flow meters are a measure necessary to control and account for water disposal. The service fee (without meters) is calculated based on the volume of liquid supplied. But there is less waste than incoming raw materials, since some of the liquid is “wasted” at the enterprises. In order not to pay for unused resources, it is necessary to install wastewater meters.
Enterprise buildings may house several legal entities. Each organization produces different amounts of liquid waste, which must be taken into account. Another factor that led to the installation of liquid waste meters is storm water - the only indicator of industrial emissions into the environment.
For accurate measurements, the equipment must be designed to work with an aggressive environment (liquid contaminated with chemicals).
Why is commercial wastewater metering necessary?
Wastewater is not an energy resource, but measurement ensures rational use of water at an industrial facility. Enterprise management, having information about the amount of waste discharged into the sewer, reduces its volume or reuses it (cleaning the area, cooling).
The rules for commercial accounting of water and wastewater establish a list of resources, the volume of which is subject to control:
- water supplied by the supplier for the specified period in accordance with the water supply agreement;
- liquid transported by the enterprise operating the pipes;
- wastewater transported by the enterprise operating communications;
- sewage from utility users;
- liquid that has undergone water treatment;
- purified sewage.
In Decree of the Government of the Russian Federation No. 776 of September 4, 2013. “On approval of the rules for organizing commercial metering of water and wastewater” outlines the principles for installing measuring instruments to control the discharge of liquid waste. The types of installations used, measurement methods and rules for verifying readings are indicated.
Types of devices by operating principle
The equipment installed in metering units is developed and installed in accordance with the legislation of the Russian Federation. Each wastewater meter undergoes mandatory certification and metrological verification. Control of the amount of waste discharged is acceptable without meters, but is based on standard tariffs (the volume of waste is equal to the amount of liquid supplied).
The procedure for commercial accounting of wastewater provides for the installation of several types of control:
- the level of waste flow is measured;
- the level and flow speed are determined.
In both cases, the data read from the equipment provides a more accurate picture than control without a flow meter.
Wastewater flow measurement
Devices record the level of liquid waste. An organization that has installed such equipment at its communication node determines the amount of drains through additional calculations using graduated tables.
Such meters are inexpensive and have both advantages and disadvantages. Flow meter advantages:
- measurements are performed with small amounts of waste;
- the flow of “aggressive” liquid containing chemicals is monitored.
Flaws:
- the margin of error is three percent;
- can be installed if the measurement area is sloped;
- reverse flow and stop are taken into account by the equipment as an expense;
- installation requires the construction of a well;
- strict compliance with the requirements regarding the length of straight sections.
Wastewater velocity measurement
The operating principle of the devices follows the “speed-area” rule. The flow meter measures the speed and level of liquid discharged into the sewer.
Compared to the previous type of equipment, this gives a smaller error, but its price is higher. Among the advantages of the flow meter, the following are noted:
- the direction of flow does not affect the measurements;
- equipment is installed on pipes of different sections and shapes;
- installation does not require additional structures.
Types of wastewater metering devices
Meters installed at the wastewater metering unit are classified depending on technical characteristics and way of working:
- ultrasonic;
- electromagnetic;
- lever-pendulum.
The equipment is stationary, and the accuracy of measurements is determined by the method of operation. Each of the flow meters is operated under the conditions specified in the technical documentation. Before purchasing a meter, you need to determine the installation location and study the territory. Find out whether it is possible to install a flow meter, since some objects may not be accessible for installation.
Ultrasonic
Universal devices installed on pipelines of any diameter (up to 9 meters) and geometry. They do not require additional structures or equipment. Ultrasonic meters are designed for measurements in an open ditch, free-flow pipe, autonomous sewer, gravity pipeline, and industrial-scale wastewater treatment plants.
Among the advantages are:
- different types of power (battery, mains);
- large amount of memory;
- versatility;
- durability;
- accuracy of results;
- work in any direction of flow.
Ultrasound equipment has disadvantages:
- difficulty in maintenance;
- rapid contamination requiring regular cleaning.
Electromagnetic
The action is based on magnetic induction. The equipment is easy to use and highly accurate.
Electromagnetic sewer meters, like any devices for monitoring discharged waste, have advantages and disadvantages. Among the advantages are noted:
- work in pressure and free-flow sewerage;
- counting of untreated waste;
- ease of installation and maintenance;
- vibration resistance.
The disadvantages of the equipment are:
- counting only drains that conduct electric current;
- disruption caused by electromagnetic interference;
- measurement error up to two percent.
Lever-pendulum
A simple device consisting of levers, a float, a power supply protection unit, a rotating blade, a suspension axis and sensors. Can only be used in a free-flow pipeline or open channel.
The advantage of the flow meter over those discussed above is its high accuracy of readings, regardless of the degree of waste contamination. The equipment is not influenced by external factors (vibration, magnetic field, flow direction).
The accounting of sewage by industrial, environmental enterprises and water utilities is just beginning to be carried out, despite the fact that the process is enshrined in law. An insufficiently developed system for monitoring liquid waste discharges does not prevent organizations that have installed metering devices from saving resources and avoiding unnecessary costs.
