I. Project Overview
Project Name: Internal Adjustment of Annual Production Capacity for Specialty Fine Chemicals (Class B) and Changes in Raw Material Transfer Methods, Safety and Environmental Protection Improvement Project;
Industry Category: Specialty Chemical Manufacturing (C2662);
Project Nature: Technological Upgrading;
Construction Location: Existing Acetic Acid Chemical Plant Area, No. 968 Jiangshan Road, Nantong Economic and Technological Development Zone;
Total Investment: RMB 30 million, of which RMB 500,000 is for environmental protection, accounting for 1.7% of the total investment;
Construction Period: December 2023 - January 2024;
Working Hours: 330 working days per year, 24-hour production (three shifts per day).
II. Construction Content and Scale
This technical upgrade will adjust the existing product plan for diethylaniline series of special fine chemicals. The total production capacity and production process will remain unchanged, and the core production equipment will not be increased. Relying on existing structures, there will be no increase in energy consumption or pollutant emissions. At the same time, the automation level of solid material feeding and packaging will be improved, and measures such as remote liquid level transmission and interlocking regulation, and shut-off valves will be added to enhance the overall automation level of production.
III. Potential Environmental Impacts of the Project and Mitigation Measures
(1) Wastewater
The technical upgrade project involves wastewater including drainage from the circulating cooling system, workshop floor cleaning wastewater, waste gas spray tower wastewater, and equipment cleaning wastewater. The amount and quality of each type of wastewater will remain basically unchanged before and after the upgrade. The drainage from the circulating cooling system will be used as floor washing water, with a total annual generation of approximately 22,480 m3 (approximately 68.1 m3/d). Relying on the company's existing wastewater biochemical treatment facility with a treatment capacity of 5,000 m3/d, a UASB + facultative + aerobic treatment process will be adopted. After treatment to meet standards, the wastewater will be discharged into the park's chemical wastewater treatment plant for further treatment. (2) Exhaust Gas
The exhaust gas from the diethylaniline and o-diethylaniline reaction and centrifuge sections in Workshop 811 is pretreated by condensation, then treated by water spraying and activated carbon adsorption before being discharged through a 20-meter-high exhaust stack DA035. The non-condensable exhaust gas from ethanol distillation is treated by condensation, water spraying, and activated carbon adsorption before being discharged through a 20-meter-high exhaust stack DA035. The exhaust gas from diethylaniline drying is treated by dust removal and water spraying before being discharged through a 30-meter-high exhaust stack DA034. The exhaust gas from o-diethylaniline drying is treated by dust removal and water spraying before being discharged through a 30-meter-high exhaust stack DA036. The waste gas from the reaction, centrifugation, and refining sections of diethylaniline products in Workshop 812 is pretreated by condensation, then treated by water spraying and activated carbon adsorption before being discharged through a 20-meter-high exhaust stack DA031. The non-condensable waste gas from ethanol distillation is treated by condensation, water spraying, and activated carbon adsorption before being discharged through a 20-meter-high exhaust stack DA033. The waste gas from the drying of diethylaniline products is treated by three sets of dust removal and water spraying devices before being combined and discharged through a 30-meter-high exhaust stack DA032.
The waste gas pollutant treatment measures and exhaust stacks for the technical renovation project are all based on existing facilities. According to predictions, the impact of the new pollution sources from the project on the surrounding environment is relatively small.
(3) Solid Waste
The solid waste disposal measures adopted in this project can achieve the reduction and harmlessness of solid waste, and it is expected that it will not have an adverse impact on the surrounding environment.
(4) Noise
The production equipment of this project is basically based on existing facilities. The main new noise source comes from the packaging line. Sound insulation and vibration reduction measures can effectively reduce the noise level at the plant boundary. It is expected that after the project is completed and put into operation, it will not change the current status of the acoustic environment at the plant boundary, and the impact on the surrounding acoustic environment will be minimal.
IV. Environmental Impact Assessment Conclusion
The comprehensive evaluation of all aspects in this report indicates that: this project complies with national industrial policies and will have high social and economic benefits after completion; the plant site is well-aligned with the regional overall plan and environmental plan; the various pollution prevention and control measures adopted are reasonable, reliable, and effective; water, air pollutants, and noise can all achieve standard emissions, and the pollutant emissions can be balanced within the company's existing permitted total amount; after the project is completed, the pollution impact on the surrounding environment will be insignificant, and the probability of environmental risk accidents is low; environmental protection investment can basically meet the needs of pollution control, achieving a balance between economic and social benefits. Therefore, in the next stage of engineering design and construction, if the pollution prevention and control measures established by the construction unit and the various environmental protection countermeasures and suggestions put forward in this report can be strictly implemented, from an environmental protection perspective, the "Nantong Acetic Acid Chemical Co., Ltd. Annual Production Capacity Internal Adjustment and Partial Raw Material Transfer Method Change Safety and Environmental Protection Improvement Project for 19,000 Tons of Special Fine Chemicals (Class B)" can be constructed in the existing plant area.
