Kev rov ua dua tshiab tau dhau los ua qhov tseem ceeb hauv lub xyoo pua 21st kom tsis txhob pov tseg thiab khaws cia ib puag ncig. Ntau yam khoom siv sib txawv tuaj yeem rov ua dua tshiab rau lub zog, roj, cov ntaub ntawv rov qab, kev kho mob lom neeg thiab kev tsim cov cement, suav nrog cov khoom pov tseg hauv nroog, kev lag luam thiab kev lag luam pov tseg, kev tsim kho thiab rhuav tshem cov khib nyiab rov qab, slag recycling, yas thiab lub hnab qhib. , ntawv thiab cardboard recycling hlau, bulky pov tseg recycling thiab lwm yam ntau ntau hom pov tseg.