1. Background

With the continuous deepening of the action plan for air pollution prevention and control, carrying out comprehensive pollution control in the local area has become a key focus of governments at all levels to achieve regional pollution reduction and environmental quality improvement goals. Dust pollution caused by numerous coal yards, material yards, and slag yards has also become one of the main sources of pollution in the urban area. The dust pollution from industrial material storage yards has the characteristics of dispersed point sources and fast changing speed; Traditional monitoring networks are difficult to meet the current demand for dust monitoring. Moreover, traditional dust control measures are mainly based on management methods, focusing on whether the construction site is watered, ground hardened, covered, and other management measures. However, the actual trend of pollution data changes has not been fully explored.

In order to implement the dust control of industrial material yards and carry out pilot monitoring of dust in material yards, the construction of a dust online monitoring system in material yards is an effective means of comprehensive management of material yards. The dust online monitoring system adopts light scattering method, which can reflect the trend of particle concentration changes in real time, and the monitoring data is accurate, meeting the purpose of trial monitoring of material yards at present.

Our company has many years of experience in producing environmental air quality monitoring equipment. Our online particulate matter monitoring device for dust has a market share of over 30%. In response to the technical needs of the dust monitoring market, our company has developed a series of beta ray dust monitoring devices and light scattering dust monitoring devices, which can be used in combination to meet different market demands for dust monitoring and solve the problem of excessive one-time investment.

2. System objectives

Firstly, install an online dust monitoring system in the material yard of industrial enterprises to achieve comprehensive monitoring of the dust pollution situation in the material yard.

Secondly, with the completion of infrastructure construction, we will improve the construction of the dust video monitoring system, adopt environmental IoT smart gateway, IoT data exchange and joint prevention and control support technology, establish a material yard monitoring center platform, build a server virtualization platform and IoT cloud platform, and basically complete networked dust monitoring to achieve the goal of self-monitoring by industrial enterprises. Through the monitoring network, we will monitor the dust emissions in the region, evaluate the contribution rate of dust emissions to environmental pollution, determine the charging standards and basis for dust emissions and pollution, and complete the construction of corresponding laws and regulations.

The monitoring parameters of the online dust monitoring system for the stacking yard are usually: inhalable particulate matter PM10, PM2.5 noise, and video monitoring.

By monitoring the inhalable particulate matter PM10, the dust generation at the construction site can be monitored.

Noise data can be used to monitor the on-site noise situation. Construction sites usually generate significant noise, causing significant pollution to the urban acoustic environment, especially during nighttime construction, which has a significant impact on urban residents;

The dust quality is relatively light and easily spreads rapidly under the action of wind; Dust in the air is also easily washed away by rainwater and falls back to the ground, but the dust that falls back to the ground will still enter the air for circulation after the moisture evaporates, forming pollution again.

Video surveillance is an important component of the online dust monitoring system for material storage yards. The on-site particle concentration obtained by the particle monitoring instrument and the on-site noise data obtained by the sound level meter cannot intuitively display the specific dust pollution situation of the construction site. By collecting on-site images and video data through a video surveillance system, the dust emission situation can be clearly understood, and it can also serve as a law enforcement basis for administrative supervision.

When the dust in the stacking yard exceeds the standard, the linkage fog cannon or spray system can be used to automatically or manually start the spray system and control the dust in real time.

3. System design ideas

3.1.1 Design concept of online dust monitoring system for material yard

The overall design concept of the online dust monitoring system for the stacking yard is shown in the following figure.

Figure 1 System Design Concept Diagram

3.1.2 Design of particulate matter monitoring instruments

The particulate matter monitoring instrument can monitor the concentrations of PM2.5 and PM10 in the air of the material storage yard in real time. The monitoring results can be used to evaluate the effectiveness of dust reduction measures in industrial material storage yards, evaluate the dust control of industrial material storage yards, and analyze the contribution rate of dust to PM2.5 and PM10 in the air based on the monitoring data of reference points.

3.1.3 Data Collection and Transmission Unit

The data acquisition and transmission unit mainly realizes the data acquisition, storage, and transmission of various monitoring instruments, as well as instrument control functions. Through system software, real-time display of current monitoring data, data query, instrument status query, alarm query and other functions can be achieved. The data collection software can implement pollution over limit alarm and capture on-site images through video surveillance system, uploading them to the management platform. At the same time, data collection can fully record the video information on site, making it convenient to review the recorded footage.

Construction of Online Monitoring Network Platform for Dust in Material Storage Yard 3.1.4

After the determination of dust monitoring points in the stacking yard, a large number of online dust monitoring systems in the stacking yard can form a complete dust online monitoring network of all monitoring systems in the urban area, realizing real-time viewing, data recording, statistical analysis and other functions of dust monitoring data, and forming regional dust monitoring maps, etc., to achieve comprehensive and efficient monitoring of dust pollution in the entire area.

Figure 3: Homepage of the Dust Automatic Monitoring Platform System

The networked management system of the automatic dust monitoring station in the stacking yard defaults to loading a map centered on the area, which is divided into ordinary map and mixed map types. Above the map is the system function navigation menu, and on the left is the surrounding city and station navigation menu tree. By using the left navigation tree, you can visually view the status of all stations in the current area. Clicking on the area or site name can zoom the map to the corresponding area or site, and you can intuitively see the site and information it belongs to. The automatic monitoring platform for dust in the stacking yard can realize the warning and capture function of the central station after the sub station parameters (particle concentration or noise) exceed the standard.

Figure 4: Warning for Excessive Particulate Matter Data

Figure 5: On site capture of particulate matter data exceeding the standard

The automatic dust monitoring platform for the stacking yard can achieve simultaneous uploading and concurrent processing of data from multiple sites, classify and summarize central data, customize query and comparison with multiple conditions, visually display lists and curves, and directly retrieve real-time videos and recordings from the site through the central station, with intelligent video query function.

4. System construction content

The monitoring parameters of the online dust monitoring system for the stacking yard include inhalable particulate matter PM2.5 PM10、 The video surveillance and online monitoring system for dust in the stacking yard mainly monitors inhalable particulate matter PM2.5 and PM10. The particulate matter monitoring instrument can monitor the concentration of PM10 in the air within the range of the stacking yard in real time. The monitoring results can be used to evaluate the effectiveness of dust reduction measures in industrial enterprises, conduct civilized production assessments of industrial enterprises, and analyze the contribution rate of dust in the stacking yard to air PM10, combined with monitoring data from reference points.

5. Implementation of system construction

The system construction includes five parts: on-site equipment installation, video system installation, power and network construction, linkage fog cannon, and overall system debugging.

5.1 Equipment Installation

The installation of system equipment includes the installation of particulate matter monitoring equipment and the installation of video systems. When installing the system, a suitable distance from the construction site should be selected to effectively monitor the dust situation in the material yard. The particle monitoring equipment and video equipment should be installed together. At the same time, the video device should be able to monitor the overall situation of the enterprise's material stacking site.

Schematic diagram of equipment installation location

5.2 Power and Network Connections

The dust monitoring system for the stacking yard requires 220V mains power, and the stacking yard can usually meet the power requirements of the system with a power consumption of 0.5KW. Network transmission can choose between wired or wireless transmission, and can work in areas covered by mobile public networks. Both power lines and network lines should be buried in pipes or laid overhead.

5.3 Overall System Debugging

After the system installation and connection are completed, it is necessary to conduct system debugging to determine whether the dust monitoring system in the material yard can work properly. Through on-site dust monitoring and testing software, the actual operation of the dust monitoring system can be visually observed.

The dust online monitoring system can observe real-time information such as particle concentration, fog cannon operation, and on-site video at the material yard.

6. Technical specification requirements for instruments

6.1 System Configuration Checklist

number	Procurement content	unit	quantity
1	Particle monitoring device	cover	1
2	Video surveillance (with protective cover and pan tilt zoom)	cover	1
3	Fog cannon controller	cover	1
4	Data acquisition instrument and acquisition control software	cover	1
5	Chassis (with temperature control, metal pole or base)	cover	1
6	Monitoring platform computer and monitoring software	cover	1
7	Central Station Software	cover	1

6.2 Requirements for each component of the monitoring system

6.2.1 Technical requirements for online monitoring equipment

6.2.1.1 AML-YC particle monitoring instrument

Monitoring method: laser scattering method

Detection parameters: PM10、PM2.5

Range: 0~500ug/m3 0~1000ug/m3

Light source: laser diode

Repetitive error: relative standard error less than 20%

Detection sensitivity: 1ug

Measurement accuracy: ± 20%

Concentration unit: micrograms per cubic meter

Working environment: 5~45 ℃ ≤ 90% RH

Storage environment:- 20~60℃ ≤90%RH

Power supply: pilot (220V) or solar power supply;

Communication method: GPRS、WIFI、 Bluetooth

Battery type: Lead acid battery

6.2.2 Technical requirements for data collection and central station software

6.2.2.1 Data acquisition device

Adopting a highly reliable universal industrial control system;

Chinese operation interface, easy for users to operate;

Real time data collection can be refreshed at a set frequency and displayed graphically. Communication ports with various monitoring instruments can be freely set, providing strong flexibility;

Automatic startup and operation function for incoming calls;

Automatic timing can achieve synchronization between time and the time of the data acquisition device;

Automatic calibration and manual calibration functions;

The parameter display unit can be switched according to user needs;

Data query function, capable of querying hourly mean, daily average, monthly mean, value, and annual mean, with visual graphical display, making it easy for users to understand the trend of various parameters over time;

The data import and export function can export historical data from a certain period of time using USB interfaces and other methods, and import this data into the central station software to achieve data transfer and storage;

Multi serial port card: expands 4 standard RS232 serial ports;

6.2.2.2 Central Station Software

Real time data and historical data query function: Users can query pollutant and meteorological monitoring data of a certain site and time at any time;

Data processing and reporting functions: The central station software processes the collected monitoring data, organizes it into mean data formats including hourly, daily, monthly, quarterly, annual, and corresponding curves, and can print and output them;

Air Quality Daily and Weekly Report Function: The central station software generates the Air Pollution Index (AQI) and pollution index history for a certain day or week;

Query function of instrument status: The central station software can real-time query the working status of each substation monitoring instrument, and record the power outage records, calibration records, instrument alarms and other status information of each substation for reference by operators;

Remote control timing function: Sub station time calibration can be performed through remote control at the central station, keeping the sub station time consistent with the central station time;

Remote control calibration: In the central control room, the monitoring instrument of a certain substation can be remotely calibrated to automatically perform zero and calibration operations;

Conversion function for multiple data formats: Monitoring data can be converted into text, EXCEL, DBASE and other file formats for output;

Beautiful interface: With a fully Chinese user interface, all tasks can be completed with just a click of the mouse;

Operation logging function: Record the operator's operation process on the central station software in chronological order.

6.3 Technical requirements for video surveillance system

6.3.1 Front end camera for video surveillance

24/7 real-time camera monitoring;

Video output supports 1280 × 960@30fps ，1280× 720@30fps ；

Supports 20x optical zoom;

Supports a minimum illumination of 0.05Lux for color, 0.01Lux for black and white, and 0 Lux with IR;

Infrared distance not less than 150 meters, supporting Smart IR anti infrared overexposure technology;

Built in heat treatment device to reduce the temperature inside the ball machine and prevent fogging of the inner cover of the ball machine;

Signal to noise ratio ≥ 52dB;

Support fog penetration, backlight compensation, digital wide dynamic, and 3D digital noise reduction functions;

Support privacy masking function;

Support horizontal manual control speed not less than 160 °/S, with a pan tilt positioning accuracy of ± 0.1 °;

Vertical manual control speed not less than 120 °/S;

Support wiper function;

Supports 7 alarm input interfaces, 2 alarm output interfaces, and 1 audio input and output interface;

Support using the mouse to select any area in the image and move it to zoom in or out to the center of the screen;

Supports 256 preset positions, supports 8 cruise scans, supports more than 4 mode path settings, and supports preset point video freezing function;

Support PTZ priority control, 485 and network can set different priorities;

Support watch function, when the standby time of the ball machine reaches the set value, it can automatically run functions such as preset adjustment, automatic cruise control, automatic scanning, mode path, etc;

Support screen character display function, up to 8 lines of character display, font size and color can be set;

Support power-off memory function;

Support timed capture and event capture upload FTP function;

The ball machine should have local storage function, support SD card hot plugging, and support up to 64GB;

Support setting the coding of the area of interest through the menu;

Supports H.264 and MJPEG video encoding standards, and supports G.711/G.722/G.726/MP2L2 audio encoding;

Support GB28181 protocol;

Support standard Onvif protocol;

Supports TCP/IP, UDP protocols, and extends support for SIP RTSP、RTP、RTCP、IPv4/IPv6、HTTP、HTTPS、802.1x、QoS、FTP、SMTP、UPnP、SNMP、DNS、DDNS、NTP、IGMP、ICMP、DHCP、PPPoE Waiting for network protocols;

Support IP address filtering function;

Support intelligent alarms such as audio anomaly detection, motion detection, video occlusion, network cable disconnection, IP address conflict, memory full, memory error, illegal access, etc;

The outdoor ball machine should have good protection performance, supporting IP66, TVS 4000V lightning protection, surge protection, and surge protection;

Has good environmental adaptability, with a working temperature range of -30 ℃ -65 ℃;

6.3.2 Hard Disk Video Recorder

Support access, storage, local preview, and playback of 200W high-definition network videos;

The device supports 4-channel 1080p (4M) high-definition network video access;

Supports 1 HDMI output and 1 VGA output; HDMI and VGA interfaces support output resolution of 1920x1080p;

The device supports one SATA interface;

Supports 4 alarm inputs and 1 alarm output interface;

Supports 1 Gigabit Ethernet port;

Support voice intercom input and enable voice intercom between PC and network camera through NVR;

Support access to network cameras that comply with standard ONVIF and PSIA protocols, and support access to third-party cameras through private protocols;

Support configuration of parameters such as resolution, frame rate, and bitrate for network cameras, as well as program upgrades, import and export of configuration parameters for network cameras through NVR;

Support automatic video continuation function, which can transmit the video recorded on the SD card (depending on the storage space of the IPC) to the NVR during the period when the front-end camera is disconnected from the network;

Support Hikvision SMART IPC intelligent cross-border intrusion detection, regional intrusion detection, audio anomaly detection, virtual focus detection, motion detection, face detection, and other intelligent detection access and related alarm linkage functions;

Support optional main stream and sub stream for recording; Support multiple recording methods such as timed, motion detection recording, alarm recording, etc; The timing and event recording parameters can be independently set, including bitrate, frame rate, and other parameters; Support setting of scheduled and alarm capture plans;

For different channels, corresponding storage capacities can be configured separately, or different storage disks can be set up;

Support retrieval and playback of video recordings in multiple ways, such as by time and event; Support event retrieval, playback, and backup functions based on intelligent detection; Support post recording retrieval based on cross-border intrusion detection and regional intrusion detection, with customizable rules for playback of critical recordings;

Support multi-level fast forward, fast rewind, single frame forward/backward, rewind, etc; Support intelligent playback, automatic playback at double speed for recordings without any events, and normal playback speed for event recordings;

Support real-time playback of any channel's recording in preview mode, without affecting the preview of other channels; Support important video file tag marking and locking function, and can perform fuzzy retrieval according to tags;

Support 4-channel 4CIF synchronous playback;

Support pan tilt control for network cameras, including automatic scanning, preset point calling, and cruise control functions;

The device supports standard ONVIF, PSIA, and GB28181 protocols; Supports IPv6 and network protocols such as TCP, UDP, RTP, RTSP, UPnP, SNMP, SADP, NFS, and SCSI;

Support SMART detection and warning technology for hard drives, and support logging of hard drive working status information;

Support the recording and querying of device operation logs, alarm logs, and system logs. The log information should include time, type, user, host address, parameter type, channel number, and event description to facilitate the analysis and statistics of device working status, alarm records, and abnormal situations;

6.4 Technical requirements for temperature control cabinet

The protection level of the cabinet is IP55;

The cabinet adopts outdoor spray coating, which has the ability to resist corrosion and electrochemical reactions with salt spray;

The cabinet adopts lightning protection and grounding treatment, with high reliability;

The bottom of the cabinet adopts a roller design to enhance its mobility;

Working temperature range: -20 ℃ to+55 ℃, relative humidity<95%;