Chemical agent capable of completely recycling power plant wastewater into circulating cooling water and preparation method of chemical agent

The invention discloses a chemical agent capable of completely recycling power plant wastewater into circulating cooling water. The chemical agent is characterized by comprising the following components in percentage by mass: 20-50% of a scale inhibitor, 15-60% of a dispersant, 10-40% of a sludge modifier, 5-10% of a pre-filming agent, 5-10% of a corrosion inhibitor, 5-10% of an anti-settling agent and the balance of water. The chemical agent meets the standard specified by DL/T806-2002 Corrosion Inhibitor for Power Plant Circulating Cooling water. Compared with the prior art, the circulating cooling water is directly injected into a circulating water system with no addition of facilities, no need of investment and no energy consumption, the circulating water system is not scaled or corroded for many years, inorganic solids and sludge formed in the running process can be cleared in the overhaul or pumped by a sludge pump and dried in air for filling pit or paving the road and thus the zero emission of the power plant circulating water system is achieved.