Lead smelting industry has been facing environmental protection
regulatory pressure for a long time due to the high sulfur content
of flue gas and complex heavy metal composition. The traditional
manual sampling and monitoring has problems such as data lag
and blind zones, and the fluctuation of SO₂ emission concentration
of some enterprises is as high as ±30%, and the fines due to
exceeding the emission standards can reach millions of dollars
every year. The automatic emission monitoring system reduces
the risk of pollutant emission exceeding the standard by 90%
through the technology of real-time sensing, intelligent analysis
and closed-loop control, and promotes the lead smelting
industry to enter a new stage of “ultra-low emission”.
I. Technical architecture: millimeter-level
sensing of pollution factors in the whole process
The lead smelting emission automatic monitoring system builds
a pollution prevention and control digital network through three
types of technical modules:
1. Multi-dimensional sensing matrix
Flue gas monitoring layer: Laser gas analyzer (TDLAS) and UV
differential absorption spectroscopy (DOAS) equipment are
deployed at key nodes such as sintering machine, blast furnace
and flue gasifier to monitor SO₂, NOx and particulate concentration
in real time, with a detection accuracy of ±1% F.S. and a data
refreshing frequency of 1 second/time;
Heavy metal capture layer: using X-ray fluorescence spectroscopy
(XRF) + inductively coupled plasma (ICP) coupling technology,
on-line analysis of lead, arsenic, cadmium and other heavy metals
in the flue gas, the detection limit is as low as 0.01mg/m³;
Wastewater monitoring layer: installing pH/ORP sensors and
heavy metal ion selective electrodes in wastewater treatment stations,
dynamically tracking 12 indicators of wastewater such as total
lead, total zinc, COD, etc., with a data deviation of <2%.
2. Edge intelligent gateway
Deploying industrial-grade edge computing equipment to
pre-process monitoring data (excluding noise, temperature
compensation), with an arithmetic power of 15TOPS, ensuring
that 95% of abnormal data are diagnosed locally;
Built-in “Lead and Zinc Industry Pollutant Emission Standard” and
other 23 regulations threshold library, exceeding the standard
data trigger alarm response time <3 seconds.
3. Cloud-side Collaboration Platform
Construct a three-level data interoperability network of plant-park-regulatory
agencies, supporting the automatic generation of multi-dimensional
reports such as hourly average value, daily average value and monthly
cumulative value;
Utilizing digital twin technology to simulate the emission diffusion path
under different working conditions, and warning the pollution risk of
surrounding residential areas 12 hours in advance.
Measured data from a lead smelter shows that after deploying the
system, the number of times the hourly average value of SO₂ emissions
exceeded the standard was reduced from 27 to 2 times per month,
and the annual environmental protection fine was reduced by 3.8 million yuan.
Second, the core function: from monitoring
to governance of the closed-loop control
1. Intelligent joint control of flue gas purification
When the concentration of SO₂ in the flue gas of the sintering machine
exceeds 800mg/m³, the amount of ammonia sprayed in the acid
system is automatically adjusted to stabilize the efficiency of
desulfurization at over 99.2%;
Dynamically control the voltage of the electric precipitator according
to the change of flue gas flow, so as to reduce the particle
emission concentration from 50mg/m³ to below 10mg/m³;
The heavy metal trapping module works in concert with the
bag filter to increase the lead dust removal rate from 92% to 99.5%.
2. Precise dosing for wastewater treatment
Based on the real-time data of heavy metal ion concentration in
wastewater, it automatically calculates the optimal dosage of
sodium sulfide, PAC and other pharmaceuticals, saving 15% of
pharmaceutical costs;
Through the membrane filtration system permeable membrane
differential pressure prediction, 8 hours in advance warning of
membrane contamination, backwash cycle extended from 48
hours to 72 hours.
3. Grid monitoring of disorganized emissions
Arrange 100×100 meters miniature air quality monitoring station in
the material yard and transportation channel to capture PM2.5 and
lead vapor concentration in real time;
Linking fog cannons and dry mist dust suppression equipment, the
unorganized emission of dust is reduced by 70%, and the
compliance rate of particulate matter concentration at the
plant boundary is increased to 98%.
4. Trusted Data Depository
Blockchain technology is used to encrypt and chain the monitoring
data to prevent human tampering and meet the requirements of the
Ministry of Ecology and Environment for “installation, tree and linkage”;
Automatically generate automatic monitoring data ledgers of
pollution sources in compliance with HJ 75-2017 standards,
and increase the efficiency of data retrieval for environmental protection audits by 90%.
Third, the application value: environmental
compliance and production optimization of
a win-win situation
1. Risk prevention and control upgrade
24-hour uninterrupted monitoring shortens the time to detect
excessive emissions from 2-6 hours of manual inspection to within
10 seconds;
Historical data traceability function helps enterprises provide a
complete chain of evidence in environmental protection litigation,
reducing legal disputes by 80%.
2. Reduced operating costs
By optimizing the dosage of desulfurizer and the operating parameters
of dust collector, the energy consumption of environmental protection
facilities for ton of lead production is reduced by 12%;
The predictive maintenance module reduces sudden equipment failure
downtime, saving more than 2 million yuan in annual maintenance costs.
3. Resource recovery and efficiency increase
Precise control of acid mist capturing efficiency has resulted in the
recovery of 12,000 tons of additional concentrated sulfuric acid per
year, generating income of 6 million yuan;
The automated collection system of leaded fume increases the lead
recovery rate from 94% to 97.5%, which increases the annual profit
by more than 8 million yuan.
4. Highlighted social benefits
The number of good air quality days around the plant increased by
45 days year-on-year, and the number of complaints from residents
decreased by 90%;
Obtaining A-class environmental performance rating, enjoying policy
dividends such as preferential tariffs and tax reductions, and
increasing annual comprehensive income by 5%.
IV. Technology evolution: AI-driven
next-generation monitoring system
1. Pollutant migration prediction
Integrate meteorological data with CFD fluid simulation to build
an atmospheric dispersion model for heavy metals, and warn the
risk of contamination of neighboring farmland 6 hours in advance;
Simulate the leakage path of lead-containing wastewater under
heavy rainfall scenarios, guide the expansion and transformation
of emergency pools, and prevent and control groundwater pollution.
2. Multi-pollutant synergistic management
Develop SO₂-heavy metal-dioxin joint control algorithm to inhibit
dioxin generation by adjusting the combustion temperature,
with emission concentration below 0.1ng TEQ/m³;
Using microwave catalytic oxidation technology to treat
arsenic-containing flue gas, the operating cost is 40% lower
than the traditional process.
3. Digital twin optimization
Construct plant-wide emission digital twins to simulate the best
combination of environmental protection parameters under
different production loads and guide the formulation of
technical reform programs;
Through the virtual reality (VR) training system, operators master
emergency regulation skills under complex working conditions,
and human error is reduced by 70%.
V. Industry change: reshaping the lead
smelting sustainable development ecology
According to the prediction of the International Cleaner Production
Organization, by 2028, the global lead smelting industry will have the
following changes due to the automatic monitoring system:
Upgrade of regulatory model: Ecological and environmental
departments will directly access real-time emission data of enterprises,
and the frequency of on-site inspections will be reduced by 50%;
Iteration of technical standards: ISO releases certification standards
for smelter intelligent monitoring systems, and enterprises that fail
to meet the standards will be restricted from participating in international bidding;
Optimization of production capacity structure: backward production
capacity accelerates its exit because it cannot afford the cost of
intelligent transformation, and industry concentration increases to over 75%;
Green financial empowerment: enterprises accessing the monitoring
system can obtain priority capital injection from ESG investment
funds, reducing financing costs by 2-3 percentage points.
Conclusion
The automatic lead smelting emission monitoring system is redefining
the boundaries of heavy metal pollution management. It is not only
an “electronic sentinel” for environmental protection, but also
promotes the lead smelting industry to move towards the sustainable
development path of clean production and efficient resource recovery
through the deep coupling of data flow and material flow. Driven
by the “double carbon” goal and digital transformation, this
technology will become the core pillar of the heavy metal
pollution prevention system, and build a solid scientific and
technological barrier to safeguard green water and
green mountains.