Baofeng Energy’s VOCs Ultra-Low Emission Project

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The project to upgrade the VOCs control system at the Second Coking Plant of Ningxia Baofeng Energy Group aims to achieve ultra-low emissions levels. It is one of the key initiatives for improving emission standards in the coking sector within the Ningdong Energy and Chemical Industry Base. The Ningdong Management Committee officially released a pre-planning announcement regarding this project on April 17, 2026; its objective is to raise the standards for VOCs, unpleasant odors, and unorganized exhaust gases throughout the entire process associated with chemical production at the Second Coking Plant (gas purification + chemical recovery), so as to meet the **latest ultra-ultra-low emission requirements for the coking industry. I. Basic Project Overview 1. Project owner: Ningxia Baofeng Energy Group Coking Plant No. 2 Co., Ltd. 2. Location of construction: Baofeng Circular Economy Industrial Park, Ningdong Energy and Chemical Industry Base, Ningxia (within the existing chemical production area of Coking Plant No. 2) 3. Nature of the project: Technical upgrades and capacity improvements to existing facilities (new construction + renovation of existing assets); no increase in coke production capacity ； Plant 2 for coking has an existing total coke production capacity of 7 million tons per year. 4. Publication date: April 17, 2026 (official publication by the Ningdong Management Committee). 5. Scope of the renovation: The entire VOCs-related system in the chemical processing workshop – including components such as cold blowers, desulfurization units, ammonium sulfate production facilities, crude benzene processing units, tar treatment systems, ammonia vaporization units, wastewater treatment plants, tank vents, water seal tanks, pump areas, and all points where odors and VOCs are generated or emitted. II. Background and necessity of the renovation: The chemical processing units in coking plants (for gas purification and recovery) are the areas where VOCs, benzene derivatives, hydrogen sulfide, ammonia, tar mist, and various unpleasant odors are most concentrated. The existing systems suffer from inadequate sealing for emission control, numerous leakage points, outdated treatment technologies, and insufficient efficiency in final purification processes; as a result, they fail to meet the requirements set out in the new “Emission Standards for Air Pollutants in the Coking Industry,” the “Ningxia Coking Plant Ultra-Low Emission Renovation Plan,” as well as the specific regulations regarding odor control in the Ningdong area ； **/Ningxia mandates that large coking enterprises with a production capacity of 7 million tons carry out upgrades to achieve ultra-low emissions across the entire process for chemical VOCs; this is a mandatory requirement for passing environmental inspections, obtaining emission permits, and maintaining operational continuity under Category A performance standards during periods of severe air pollution. III. Main construction and renovation contents (key information disclosed officially) (I) Comprehensive upgrade of the source sealing and collection system: 1. All tanks in the cold drum section, including those for tar-ammonia separation, ammonia clarification, excess ammonia storage, primary cooler water seals, blower water seals, and intermediate tar storage, will be fully sealed and covered; open-type vent valves will be replaced, and sealed collection pipes, control valves, and flame arresters will be installed ； 2. Conduct airtight renovations on the saturator, overflow tank, crystallizer, and ammonia distillation wastewater tank in the ammonium sulfate section; collect all exhaust gases under negative pressure to prevent any uncontrolled emissions ； 3. Closed recovery of breathing exhaust gases from crude benzene and tar storage tanks, benzene hydrogenation units, and chemical product intermediate tank areas ； All dynamic and static sealing points such as pump areas, flanges, and valves have been fully upgraded with the LDAR leakage detection and repair system ； 4. VOCs from the anoxic tank, sedimentation tank, and biological treatment tank in the sewage treatment plant are collected through enclosed systems with covers. (II) Modification of the intermediate-stage pretreatment and purification system: Construction/upgrade of a pretreatment unit consisting of an acid washing tower and an alkali washing tower – for ammonia removal and elimination of acidic malodorous gases through acid washing ； Alkaline washing for desulfurization and removal of acidic organic substances ； Removes tar mist, naphthalene, and particulate impurities to protect end-stage oxidation equipment ； A new gas-liquid separator, circulation liquid system, induced draft fan, automatic control system, online monitoring for combustible gases/oxygen, and an emergency quick-shut flame arrestor system have been added. (III) Advanced oxidation treatment system for end-stage VOCs (core ultra-low emission technology): All waste gases generated throughout the plant are collected together, and an efficient pre-treatment process combined with regenerative thermal oxidation (RTO) is used for thorough combustion of these gases: 1. Waste gases are preheated to temperatures above 850°C to ensure complete oxidation and decomposition of VOCs, benzene derivatives, polycyclic aromatic hydrocarbons, and malodorous substances ； 2. Recovery and utilization of waste heat to reduce operating energy consumption ； 3. End-mounted wet electrostatic dust removal system to remove fine particulates, white smoke, and mist droplets ； 4. Online continuous monitoring of flue gas (FID/VOCs, benzene, SO₂, NOₓ, particulate matter), connected to the environmental protection department’s supervision platform. (IV) Supporting utilities and environmental protection facilities: new main exhaust gas pipelines, explosion-proof fans, automatic control PLC systems, online monitoring systems, emergency venting systems, fire and explosion prevention measures, as well as environmental inspection and monitoring systems. IV. Overall process flow: Closed-negative-pressure collection at various stages in the chemical production process → Acid washing for ammonia removal → Alkali washing for desulfurization and impurity removal → Mist and water removal → Pressure stabilization and mixing → RTO high-temperature thermal oxidation → Waste heat recovery → Wet electrostatic mist and dust removal → Emission through a chimney that meets regulatory standards. V. Environmental benefits after the renovation (ultra-low emission indicators) 6. Renovation objectives: To achieve in-depth treatment of organized VOCs emissions, comprehensive enclosed collection of unorganized emissions, refined management and control through LDAR, and complete elimination of odors, thereby meeting the latest local ultra-low emission standards for the coking industry in Ningxia. 1. The overall removal efficiency of VOCs is ≥98%; benzene, non-methane total hydrocarbons, and polycyclic aromatic hydrocarbons (benzo[a]pyrene) all meet the ultra-low emission limits for coking industries ； 2. The concentrations of hydrogen sulfide, ammonia, and foul odors have decreased significantly, with all unpleasant smells in the factory area eliminated ； 3. Unorganized emissions have fully met the standards, with LDAR leakage rates significantly reduced ； 4. Complete the targeted treatment of odors from coking at the Ningdong facility, and upgrade its emission performance to Grade A, thereby achieving significant annual reductions in VOCs, benzene compounds, and other malodorous pollutants. VI. Project Progress: On April 17, 2026, the pre-approval public notice for the plan was completed ； The project has completed registration and conceptual design; it is now poised to enter the stages of construction drawing design, equipment bidding, and on-site construction ； The project is generally contracted and constructed by China Chemical Engineering Fourteenth Construction Company and other entities