In environmental protection,humic acid plays an important role in the treatment of polluted water contends metals like lead, zinc, cadmium, mercury, nickel, chromium and other heavy metal . Shanghai East China Institute of Chemical Engineering test wastewater contend cadmium treatmentr, after one year continuous operation got the following result : saturated Ni2 + (2 * 2 mm), 0.92 eq / g (1.5 x 2 mm); the regeneration efficiency is about 95% and the eluent contains 1.5 to 10 milliequivalents per gram; Ni2 + 15 ~ 20 g / l, long-term immersion in water without humic acid dissolution. This test passed the Shanghai city identification and award. In addition, there are the use of humic acid ammonia absorption capacity for fecal deodorization, fishing port in addition to fishy, etc .In the waste gas desulfurization, deoxidation also has application. Also for polluted soil can recovered completely and thoroughly,without side effect.Not like other chemicals,if you want to cure one polluted problem you will have to take another one inside.