In March 2018, Jiangsu New Yangzi Shipbuilding Co., Ltd. signed an agreement with Jiangsu Nanfang Coating Environmental Protection Co., Ltd. to purchase coating exhaust gas treatment equipment (VOCs). The total investment of this set of equipment is 8.85 million yuan. At present, 12 sets of exhaust gas treatment equipment are installed in the painting workshop to ensure that the exhaust gas generated by painting meets the standards.

The annual maintenance cost of the enterprise is about 2.16 million yuan: each equipment works for about 3 hours a day, and and the air exchange rate of each set of equipment is 80000 cubic meters per hour, totaling 2.88 million cubic meters per day and about 1.05 million cubic meters per year. The power of the equipment is about 145KW/h, and a single equipment consumes about 435 KWH of electricity every day. The total annual power consumption of 12 sets is 1,905,300 KWH, with an average of 0.67 YUAN/KWH and an annual cost of about 1,276,600 yuan. The filling amount of activated carbon for each set of equipment is 10 square meters, the new purchase price is 5000 YUAN/square meter, the catalyst is 140kg, the new purchase price is 155 yuan/kg, the activated carbon is planned to be replaced once a year, the annual replacement cost of a single set is 51,550 yuan, the annual cost of 12 sets is 618,600 yuan; The waste carbon is about 4.8 tons, and the annual replacement volume is 57.6 tons. The treatment cost is 4,600 yuan/ton, or 265,000 yuan.