Purchased toluene distillation residues (containing approximately 87% toluene and other organic solvents) are transported to the raw material oil tank farm for storage. They are then pumped into the still pot of the primary distillation tower via a raw material oil pump. The temperature is raised and controlled; under negative pressure, the primary distillation products within the temperature range of 70°C to 80°C are extracted as light components, and the primary distillation products within the temperature range of 110°C to 120°C are extracted as the finished toluene product. The primary distillation system operates under negative pressure, and a water-ring vacuum pump is used to create a vacuum for the primary distillation system.

A. The liquid from the top of the primary distillation tower is condensed and recovered through a condensation tower. During the recovery process, a small amount of non-condensable tail gas that cannot be condensed still contains residual toluene gas. This gas is collected under negative pressure and, together with the vacuum pump tail gas, sent to an activated carbon adsorption device for adsorption treatment, then discharged through an exhaust stack.B. Through the previous heating process, the finished product receiving tank contains water-bearing steam. This part of the steam is separated by a steam-water separator. During the separation process, toluene gas is generated. The volatile gas collected via the vacuum pump connection is sent to an activated carbon adsorption device for adsorption treatment, then discharged through an exhaust stack.C. The "large and small breathing" of solvent storage tanks (gas emissions caused by temperature/pressure changes and liquid level fluctuations) generates organic waste gas, which is discharged in an unorganized manner. The emission volume and pollutant concentration of this part of the waste gas are estimated uniformly.D. All heat supply for this project is provided by the industrial park's steam system.E. During the production process, equipment such as material transfer pumps and fans used for waste gas treatment will generate noise, with a sound source strength of approximately 65~95 dB(A).F. After primary distillation by the primary distillation unit, under negative pressure, the primary distillation products within the temperature range of 70°C to 80°C are extracted as light components. The light components mainly consist of water and other substances. After standing for stratification, the separated wastewater is sent to the wastewater treatment station for treatment, and the separated substances are sold externally as auxiliary materials.G. Condensed water is generated during the condensation process. This condensed water is recycled for reuse and not discharged externally.