US 12,441,638 B2
Treatment method of leachate of hazardous waste landfill site
Wenbiao Wu, Guangdong (CN); Wenbin Xu, Guangdong (CN); Menglan Xu, Guangdong (CN); and Weining Qin, Guangdong (CN)
Assigned to Dongjiang Environmental Company Limited, Shenzhen (CN)
Appl. No. 18/014,118
Filed by Dongjiang Environmental Company Limited, Guangdong (CN)
PCT Filed Dec. 29, 2021, PCT No. PCT/CN2021/142247
§ 371(c)(1), (2) Date Dec. 30, 2022,
PCT Pub. No. WO2023/103119, PCT Pub. Date Jun. 15, 2023.
Claims priority of application No. 202111502275.1 (CN), filed on Dec. 10, 2020.
Prior Publication US 2024/0092663 A1, Mar. 21, 2024
Int. Cl. C02F 1/04 (2023.01); C02F 1/38 (2023.01); C02F 1/52 (2023.01); C02F 1/66 (2023.01); C02F 103/06 (2006.01); C02F 101/12 (2006.01)
CPC C02F 1/66 (2013.01) [C02F 1/04 (2013.01); C02F 1/38 (2013.01); C02F 1/5245 (2013.01); C02F 2001/5218 (2013.01); C02F 2101/12 (2013.01); C02F 2103/06 (2013.01); C02F 2209/02 (2013.01); C02F 2209/06 (2013.01); C02F 2209/44 (2013.01)] 3 Claims
OG exemplary drawing
 
1. A treatment method of a leachate from hazardous waste landfill site, comprising the following steps:
at step 1, adding sodium carbonate for completely removing calcium ions in the leachate to the leachate for 30 min of reaction and then obtaining a calcium carbonate residue and a first waste liquid through filtration;
at step 2, adding hydrochloric acid to the first waste liquid and adjusting a pH value to obtain a first mixed solution;
at step 3, heating the first mixed solution to 80° C., and then introducing a given amount of chlorine gas to the first mixed solution while introducing air for performing blow-off reaction and then obtaining a second waste liquid and a first mixed gas;
at step 4, introducing the first mixed gas into an alkaline liquid absorption tower to obtain an absorption liquid and feeding the absorption liquid into a bromine recovery apparatus for recovering bromine;
at step 5, heating the second waste liquid to 100° C. to enable the second waste liquid to be evaporated so as to obtain an evaporation condensate water and a concentrated liquid;
at step 6, centrifuging the concentrated liquid to obtain a sodium chloride wet salt and a centrifuged liquid;
at step 7, pumping the centrifuged liquid into a cooling crystallization tank, such that, when the centrifuged liquid is cooled to 40° C., a potassium chloride wet salt and a final mother liquor are obtained by centrifugation;
at step 8, returning the final mother liquor to the first waste liquid or the second waste liquid for recycling.