Combining with the production practice in the particular consortium of the paper mill, power plant and calcium carbonate fines factory, a new kind of united treatment technology is designed. The technology is mixing the waste pulp and waste scum with coal to finish the in-furnace desulphurization, spraying waste water to the flue gas to finished flue gas desulphurization and using waste hydrogen of calcium as absorb material. This method can comprehensive use of resource to reach a better economic effective and social benefit. It reduces the processing cost and avoids city environment pollution. The three factories have mutually pleasant business. The technology opens up a new effective approach of desulphurization and can be good example to the same enterprises. An economical benefit is analyzed.