HJ 915-2017Technical specifications for automatic monitoring of surface water (Trial) (English PDF)

4.1 General requirements

The construction of automatic water quality monitoring system mainly includes.

the construction of selection of site, construction of station building, water

station units and data platform. Among them, the instrument's performance

indicators shall meet the requirements of Appendix A.2, the construction of

system refers to the requirements of Appendix B.

4.2 Selection of site

The principles for site selection include feasibility of station construction,

representation of water quality, long-term monitoring, system safety and

operational economy.

In order to ensure the long-term stable operation of the automatic water quality

monitoring system, the selected site shall have good traffic, electricity, clean

water, communication, distance of water collection point, water collection head,

feasibility of water collection in dry season, operation and maintenance safety,

and other basic conditions for the construction of station building.

The monitoring results of the selected sites can represent the water quality

status and changing trends of the monitored water bodies. The river monitoring

section is generally selected in a straight river section where the water quality

is uniformly distributed and the flow rate is relatively stable, more than 1 km

away from the upstream estuary or sewage outlet. In principle, it is consistent

with or similar to the original conventional monitoring section, to ensure

continuity of the monitoring data. The lake reservoir section shall have a good

hydraulic exchange, the location can fully reflect the true state of the water

quality of the lake reservoir in the monitored area, avoid setting it in the

backwater zone, the stagnant water zone, or the place where sedimentation

and watergrass growth are likely to occur.

4.3 Construction of station building

For the construction of the station building, according to the actual situation of

the site environment, construction period, installation conditions of monitoring

instrument & equipment, and so on of the station site, it adopts the fixed station,

simple station, small station, water fixed platform station, water buoy (ship)

station, etc., for system construction. The design and construction of the station

building is combined with the surrounding environment conditions such as

geological structure, water level and climate. At the same time, it shall take

measures such as lightning protection, earthquake resistance, flood control,

low-temperature resistance, rodent prevention, fire prevention, anti-theft, anti-

power failure, video surveillance, and so on. The station building is designed

with the facilities for waste liquid treatment and domestic sewage collection.

The construction of the fixed station building includes the main building for

carrying the system equipment and the external supporting conditions. The

main building consists of the instrument room, the quality control room, the

living room of the duty guard. External supporting conditions refer to the

introduction of clean water, electricity, communications, building access roads,

flattening, greening, solidifying the land covered.

The simple station building and the small station building are suitable for the

construction of water stations which have limited floor space, complicated

geographical conditions, short project construction period, the need to relocate

or adjust the monitoring section. The design dimensions of the station building

shall meet the installation requirements of the instrument and system integrated

device. The material of the station building should be made of light materials,

which have functions such as constant temperature, heat insulation, rain proof

and alarm, etc.

The water fixed platform station and the water buoy (ship) station are a

monitoring system that integrates monitoring instruments on the platform and

is equipped with power supply equipment such as solar energy and wind energy,

has functions such as warning against collision and alarming, etc.

4.4 Construction of each unit of water station

4.4.1 Water collection & distribution unit

The water distribution & distribution unit is the key part to ensure the normal

operation of the whole system and to obtain the correct data. It must ensure

that the water samples provided are reliable and effective, including the water

collection unit, the pretreatment unit and the water distribution unit. The water

collection unit includes the water collection method, the water collection pump,

the laying of water collection pipeline. The pretreatment unit provides

pretreatment device for different monitoring items, to meet the requirements of

the analytical instrument for the settling time and filtration accuracy of the water

sample. The water distribution unit supplies water directly to the automatic

monitoring instrument, the water quality, water pressure and water quantity

provided by the water distribution unit must meet the requirements of the

automatic monitoring instrument.

4.4.2 Control unit

The control unit is the command center that controls the coordination of the

various units within the system.

4.4.3 Detection unit

The detection unit is the core part of the automatic water quality monitoring

system. It consists of automatic monitoring instruments that meet the

requirements of each detection item. The principles for selecting the instrument

is that the instrument's measurement accuracy meets the requirements of water

quality analysis and meets the requirements of the analytical methods specified

by the state. The selected instrument has reasonable configuration and stable

performance; the operation and maintenance cost are reasonable, the

maintenance work amount is small, the secondary pollution is small.

4.4.4 Data acquisition and transmission unit

Data acquisition and transmission are required to be automatically executed in

accordance with the analytical cycle, and to enable remote control, automatic

encryption and backup. The acquisition device adopts a unified communication

protocol according to national standards, to realizes transmission of data and

main state parameters in a wired or wireless manner.

4.5 Construction of data platform

The data platform is an operating system that integrates data and state

collection, processing and generation of various types of statements. It has the

collection of field data and main state parameters, conditional back control of

field systems and instruments, data analysis and management, generation and

reporting of statements, alarming, and other business functions. The data

platform software adopts a safe and stable data transmission mode, has

functions such as regular automatic backup, automatic classification alarming,

remote monitoring, and so on, and has expandability.

5.1 General requirements

The acceptance of automatic water quality monitoring system includes the

acceptance of the construction of station building and external supporting

facilities, the acceptance of instrument and equipment, the acceptance of data

transmission and data platform. See Appendix C for details of the acceptance

and corresponding forms.

5.2 Acceptance procedures

a) Carry out instrument performance test and laboratory comparison, entrust

qualified organizations to verify the infrastructure such as station power

supply and lightning protection, conduct trial operation according to the

specified time;

b) Prepare an acceptance report, submit an application for acceptance;

c) Check the completion of the site, organize an acceptance meeting, form

an acceptance opinion;

d) Organize the acceptance data and archive it.

5.3 Basic conditions for acceptance

The acceptance of automatic water quality monitoring system shall meet the

following conditions.

a) The power supply, communication, water supply, traffic, lightning

protection, fire prevention, anti-theft and other infrastructure of the station

building meet the requirements;

b) The monitoring instrument, equipment and accessories are supplied in

accordance with the contract, the appearance is not damaged;

c) Complete the instrument's performance test, comparison test, the

technical indicators meet the relevant national technical specifications and

contract requirements;

d) Complete the communication test of the automatic water quality

monitoring system, upload the water station's data to the data platform;

e) Complete the operation of automatic water quality monitoring system for

at least 30 consecutive days;

f) Establish a file for the automatic water quality monitoring system, prepare

an acceptance report.

5.4 Acceptance content

5.4.1 Acceptance of station building and external supporting facilities

The completion acceptance of the station building and external supporting

facilities shall comply with the requirements of national standards, current

quality inspection and evaluation standards, construction acceptance

specifications, design documents approved and relevant laws, regulations,

rules and regulatory documents. Check the entity quality of the project, check

the completion data as provided by the parties involved in the construction,

conduct random inspections and tests on the use functions of the construction

project. If problems are found during the acceptance process and the

completion acceptance criteria are not met, it shall instruct the construction

party to immediately rectify it, meanwhile re-determine the time to organize the

completion acceptance. The technical requirements for the construction of the

station building are as shown in Appendix B and the contract.

5.4.2 Acceptance of instruments and equipment

5.4.2.1 Arrival acceptance

According to the contract, make an inventory of each automatic monitoring

equipment, system integration equipment, data platform hardware system, data

acquisition control system, etc.; check the exit-factory number and quantity of

specific equipment and spare parts according to the packing list; check the

appearance of equipment and spare parts. Take pictures of the parts with

appearance damage and deal with them according to the contract.

5.4.2.2 Acceptance of instrument and equipment performance

The acceptance of instrument and equipment performance is mainly for testing

the performance indicators of the instrument and equipment as specified in this

standard. Each equipment shall be accepted in an environment that meets the

requirements. The inspection indicators and judgment criteria meet the relevant

indicators in Table A.2 of Appendix A, the requirements of relevant standards

and contracts. The main contents of the acceptance include, but are not limited

to, the following items. instrument installation, power-on, preheating test,

instrument initialization test, checking of instrument's basic function, detection

limit, accuracy, precision, checking of standard curve, zero drift, span drift,

checking of response time, checking of repeatability or repeatability error,

comparison of actual water sample. Record the results and make summary.

5.4.3 Acceptance of data transmission and data platform

Under the premise that the automatic monitoring instrument's performance is

accepted, check whether such indicators as the data transmission of the

automatic monitoring system, the data platform function, the software

performance and so on meet the requirements of national standards and

related technical indicators of the contract.

6.1 General requirements

The operational maintenance of the automatic water quality monitoring system

includes routine maintenance of water station at regular interval, maintenance

and repair, troubleshooting, downtime maintenance, daily management and

recording of the data platform, etc.

6.2 Technical requirements for operational maintenance of water station

6.2.1 Routine maintenance

Routine maintenance includes station building's surrounding inspection,

inspection of instrument and system, replacement of consumables,

replacement of reagent, pipeline cleaning, and so on. The operational

maintenance organization shall conduct regular patrol inspections of the water

station, the frequency of patrol inspection shall not be less than once a week,

the conditions of patrol inspection shall be recorded. The following work is

performed each time performing patrol inspection of the water station.

a) Check the operating status and main technical parameters of each

analytical instrument and auxiliary equipment, to determine whether the

operation is normal; check whether the power supply, process

temperature, stirring motor, sensor, electrode and working sequence are

normal; check whether there is liquid leakage, whether there is air bubble

in the pipeline; regularly clean the conventional five parameters,

chlorophyll and blue-green algae electrodes;

b) According to the operation of the instrument, the water quality of the

section and the environmental conditions of the water station, determine

the replacement cycle of consumables (such as pump tubes, joints,

seals, etc.), ensure finishing replacement before the expiration of the

consumables; if it is necessary to replace the spare parts (such as

electrodes), it shall have inventory to ensure timely replacement;

c) Check the reagent status, add and replace reagents regularly. The pure

water and reagents used must meet the relevant technical requirements.

The replacement period shall not exceed the shelf life of the reagents as

specified in the operating procedures or instrument specifications. It shall

shorten the replacement period when the indoor temperature is high. Each

time the primary reagent is replaced, it shall recalibrate the instrument

according to the appropriate operating procedures or instrument

instructions. Reagent shall be prepared by a qualified laboratory, providing

proof of reagent source and labeling;

d) Timely organize the station building and instrument, complete the

collection of waste liquid, do well in the processing and disposal according

to the relevant requirements, keep the file for future reference; keep the

water station building and all instruments clean and tidy, close the doors

and windows in time, to avoid all kinds of analytical instruments from

exposure to direct sunlight;

e) Check whether the water collection system and the water distribution

system are normal, such as the fixed condition of the water collection buoy,

the operation of the self-priming pump, etc.; regularly clean the water

collection & distribution system, including the water collecting head, the

bucket, the pump body, the grit chamber, the filter head, the water sample

cup, the valves, the related pipelines, etc., it shall timely replace those

which cannot be cleaned;

f) Check whether the power circuit system of the water station is normal,

whether the grounding circuit is reliable; check whether the sampling and

draining pipelines are leaking or blocked, whether the drainage and

exhausting device work normally;

g) Check the air conditioning and thermal insulation measures of the station

building, to keep the temperature stable; check the fixing conditions of the

pump and the air compressor, to avoid vibration of the instrument; check

the operation status of auxiliary facilities such as air compressor,

uninterruptible power supply (UPS), algae removal device, pure water

machine, etc.; replace consumables in time, empty the air compressors;

h) Check the operation status of the industrial personal computer, whether it

is poisoned or not, back up the field data and control software at least

once every quarter; check whether the communication line between the

instrument and the system is normal, whether the data deviation of the

analog transmission meets the requirements;

i) It shall remove timely the weeds and accumulated water around the station

building, check whether the lightning protection facilities are reliable,

whether there is rain leakage in the station, whether other facilities outside

the station are damaged or flooded; if any of the above problems are found,

they shall be handled in time to ensure the safe operation of the system.

Do well in the maintenance of thermal insulation of water collection

pipelines and station before the freezing period comes;

j) Make the work records of daily routine maintenance; take photos for

important work for archiving.

6.2.2 Maintenance and overhauling

According to the environmental conditions of the system operation, overhaul

the instrument and equipment of the system which are in operation within the

specified time to prevent the occurrence of faults. When there is a backup

instrument as a guarantee, it shall use the standby instrument to replace the

monitoring analysis equipment that is running in the water station, send it to the

laboratory for maintenance and overhauling; if there is no backup instrument as

a guarantee, it may carry out maintenance & overhauling at site. The

maintenance & overhauling plan shall be established based on the

configuration of the system instrument and equipment and the requirements of

the equipment manual.

a) The monitoring instrument and equipment of the water station shall be

maintained and overhauled at least once a year;

b) According to the requirements specified by the manufacturer's use and

maintenance manual, based on the service life, replace the key

components such as light source, electrode, peristaltic pump and sensor

in the monitoring instrument;

c) Perform inspection of the leakage and pressure of the liquid path of the

instrument; inspect and clean the optical path, liquid path, circuit board,

various connectors and sockets, etc.;

d) Check and calibrate the output zero and full scale of the instrument, check

the output linearity of the instrument;

e) After completing each overall maintenance and overhauling, or after

replacing the key components such as light source, electrode, peristaltic

pump, sensor, etc. in the instrument, it must calibrate and check the

instruments again, record the overhauling and calibration information.

6.2.3 Troubleshooting

Troubleshooting refers to the targeted inspection and repair of faulty instrument

and equipment. Troubleshooting shall be done as such.

a) According to the characteristics of the instrument used and the

maintenance manual provided by the manufacturer, prepare the work

instructions for judging and repairing common faults;

b) For problems that can be clearly diagnosed at site and can be solved by

replacing spare parts (such as the control failure of solenoid valve, the

rupture of pump tube, the blockage of liquid path, the aging of light source,

etc.), it shall be troubleshooted at site;

c) For other faults that are difficult to diagnose and repair, it shall use the

standby instruments to replace the faulty instruments; send the faulty

instruments or spare parts to the laboratory or the instrument

manufacturer for inspection and maintenance;

d) After each troubleshooting, according to the troubleshooting items and the

replaced parts, calibrate the instruments. For maintenance of the common

consumables (such as replacement of pump tube, cooling fans, fluid path

joints or connectors), it shall perform at least calibration of standard liquid.

For maintenance of critical components (such as maintenance of moving

mechanical parts, optical components, testing components and signal

processing components), follow the requirements of the instrument

standards and specifications to check the standard curve and precision.

All troubleshooting results shall be recorded as required for reference.

6.2.4 Downtime maintenance

Short-term shutdown (downtime less than 24 h). Normal shutdown, the

instrument must be recalibrated when running again.

Long-term downtime (continuous downtime more than 24 h). When the

analyzer needs to be shut down for 24 h or more, turn off the analytical

instrument and injection valve, turn off the power; use pure water to clean the

peristaltic pump and reagent pipeline of the analytical instrument; clean the

measuring chamber and empty it; be sure to remove the measuring electrode

and immerse the electrode tip in the protective solution for preservation. It shall

calibrate the instrument again before running it again.

6.3 Daily management of data platform

For the data platform, it must arrange personnel to understand the equipment

operation and water quality. At every morning and afternoon, remotely observe

the monitoring data of the water station at least once through the data platform

software. Based on actual conditions, organize performing such work as patrol

inspection, verification, maintenance, and so on, to ensure the normal and safe

operation of the water station. The daily management work of the data platform

includes.

a) Check the data transmission, instrument and related system parameter

data of each water station, any problem found shall be handled in time;

b) When the data is found to have persistent outliers, it shall immediately

arrange the technicians to go to the site for investigation; if necessary,

collect the actual water samples for manual analysis;

c) Retrieve and analyze the monitoring data of the water station;

d) Report the monitoring results;

e) Ensure that the hardware and software of the used and backup computer

systems are running normally; regularly update the system software,

water quality's monitoring software, anti-virus software; back up the

system monitoring data once every quarter...

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