Solution for a printing company
Player: Printing company
Issue: After an expansion of factory production equipment, exhaust gas containing volatile organic compounds (VOCs) became subject to the Air Pollution Control Act
Properties contributing to the solution: BAC, the bead-shaped activated carbon used in exhaust gas treatment equipment for VOCs, offers outstanding flowability and high wear resistance with excellent adsorption capabilities, strength, and durability
To address harmful substances emitted from factories and plants amid worsening air pollution, focus on ESG and SDGs has resulted in demands becoming stronger than ever for VOC emissions control based on laws, regulations, and ordinances for environmental protection and emissions management. The company, which is in the printing industry, also needed to explore solutions to deal with these circumstances.
Following the improvement and expansion of its production equipment, the company’s exhaust gases contained VOCs and became subject to the Air Pollution Control Act. Accordingly, the company needed exhaust gas treatment equipment to eliminate the VOCs. After discussing solutions, they decided to explore the introduction of exhaust gas treatment equipment using adsorbents instead of combustion treatment, as they considered that the levels of VOC components in its exhaust gas were very low and could be recovered and reused.
However, several problems arose. The matter of adsorbents was particularly important. As an adsorbent, many treatment systems use activated carbon made from coconut shell or coal in either granular or fiber form. Moreover, exhaust gas treatment equipment using this material involves not only the initial cost, but also higher operating expenses than we had envisioned, including the cost of replacing and disposing of the activated carbon.
BAC, the petroleum pitch-based, bead-shaped activated carbon used in a fluidized bed, excels in wear resistance and flowability and offers high adsorption capability, high strength, and high durability. It is also reusable and has a long lifetime, thereby lowering operating expenses. Unlike other equipment, our exhaust gas treatment system, GASTAK, repeatedly performs adsorption and desorption as the activated carbon moves between the adsorption tower and the desorption tower, enabling the efficient recovery of highly pure VOC solvent.*
*“Reusability,” “long lifetime,” and “efficient recovery of highly pure VOC solvent” vary with the specific type, concentration, and other conditions of the VOC exhaust gases subject to adsorption and desorption.
The use of fluidized bed adsorption means the bead-shaped activated carbon forms a multiple-level fluidized layer in the adsorption tower and successively adsorbs and eliminates VOCs. The activated carbon is indirectly heated in the desorption tower to desorb VOCs, which are then cooled, liquefied, and recovered. Accordingly, only cleaned gas is released into the atmosphere, meeting the regulatory values of the Air Pollution Control Act. Compared with combustion-based treatment, the system emits little CO2 and seems to contribute considerably to reducing environmental impacts. Moreover, as the system can liquefy and recover about 95% of the VOCs, it can distill and purify these for reuse as highly pure recovered solvents, which also reduces operating expenses. According to cost simulations based on current VOC emission amounts, the initial cost could be recovered within 42 months (about 3.5 years).