In the daily operations of a new materials laboratory, wastewater and exhaust containing pollutants such as organic solvents, acids and bases, and heavy metals are generated. With stricter environmental law enforcement, treating lab wastewater and exhaust has shifted from being "optional" to "mandatory"—if environmental reviews fail, the entire lab could be ordered to shut down.

Wastewater treatment should be carried out in layers: the first layer is source classification and collection—organic and inorganic waste liquids must be stored separately to avoid heat generation or toxic gas formation when mixed; the second layer is pretreatment—waste liquids containing heavy metals or high concentrations of organics need simple pretreatment in the lab (such as pH adjustment or activated carbon adsorption) before entering the collection system; the third layer is centralized treatment—small labs can hire qualified hazardous waste disposal companies for regular pickup, while medium to large labs can install integrated wastewater treatment systems (neutralization + flocculation + filtration + activated carbon adsorption).

For exhaust treatment, fume hoods and the exhaust from atomic absorption/ICP instruments contain acid mist, organic vapors, and particles. Solutions include a combination of activated carbon adsorption and scrubbers, and the treated emissions must meet the Integrated Emission Standard of Air Pollutants (GB 16297). Labs should incorporate wastewater and exhaust treatment plans into the overall design from the start, rather than trying to fix issues after construction—the cost of "build first, fix later" is 2-3 times that of "planning right from the start."

Dehui Science & Instruments (www.dehuisci.com) provides environmental compliance solutions for wastewater and exhaust as part of their complete laboratory delivery services. Phone: 0512-67071902.