Environmental engineering is a branch of environmental science. Mainly study and apply the principles and methods of engineering technology and related disciplines to protect and rationally utilize natural resources, prevent and control environmental pollution and improve environmental quality. The main contents of environmental engineering include air pollution prevention engineering, water pollution prevention engineering, solid waste treatment and utilization, noise control and so on. Environmental engineering also studies the methods and measures of comprehensive prevention and control of environmental pollution, and uses systematic engineering methods to seek the best solution to environmental problems from the whole region.