| Coal fly ash, t he coal burni ng solid waste of a power plant, can betreated appropriatel y and synthetized i nt o ze ol i t e for wat er puri fi c at i on.As for synthetized zeolite, the conventional research mainly focuses oncation exchange per for mance and re moval of heavy metal ions fr om water,and the synthetized zeolite is r arely used for si multa ne ous re moval ofammo nium and phosphate from waste water, besi des, t he effect that t hesynthetized zeolite is directly used for the treatment of low-concentrationphosphate-cont aini ng waste water is not good, there for e, a ppr opriatemodification treatment of zeolite and strengthening the capacity that thezeolite is used for the removal of ammonium and phosphate are necessaryto be c arr ied out.The research prov es that such rare-ear th elements as La, Ce and thelike are provided with strong adsor ption char act eristic, but the cost thatonly rare-earth elements are used to t reat wast e wat er is high, a nd the i oncontents of rare-earth elements in t he treated wast e wat er commo nly ishigh or even superstandard, the above restricts the application of zeoliteto the pr actical water treat ment. The rare-ear th elements are used formodi fic at ion of c oal fl y ash z eol i te, whi ch not onl y i mpr ove theadsorption performance of coal fl y ash zeolite, but also reduce economycost, and enables the large-scale application of coal fl y ash zeolite to bepos sible.The l o w-cost z eoli te was s y nthe size d fr om c o al fl y a s h of powerplant s t hr ough the modi fie d hydr other mal proc ess, a nd further tr eate dthrough the tombarthite La modi fic at ion t o i mprove its a mmoni um a ndphosphate re moval e fficie nc y. The e xperi me nt s foc use d on t esti ng t hei mpact of modi fie d la ntha num c onc e ntration, pH on a mmoni um andphosphate re moval, modi fic a tion ti me, and soli d-to-li qui d ratio on themodi fic at ion e ffe c t. X-r ay di ffracti o n (XRD) a nd sc a nning ele ctroni cmic r osc op e (SE M) w e r e a ppl i e d t o o bser ve t he p h ysic a l-c he mic alcharacteristics of synthesized zeolite. Besides, the synthesized zeolite isused for s ti multane ous re mo val of ammo nium and phosphate on simu latethe the effl ue nt of a second ary treat ment process of a wast ewat ertreat ment pl ant, di scuss the infl uence of mo dified lanthanumconc entra tion,us age, re action ti me, modi fic ation PH, mo dification time and solid-to-liquid ratio on its Application Effect, a n d a i ms t o e x p l o r eremoval of ammonium and phosphate by coal fly ash synthesized zeolite,and to broaden coal fl y ash synthesized ze olite application field, therebyachieving the purpose of treating waste-wate r wit h wast es.Res ult s h ows that Cati on e x change ca peity (CEC) was hi gh under t heSynthesis Conditions of solid-to liquid ration at1:5, the concentration o falkali at3mol/L,re action temperat ure at100℃,reacti on ti me at24h. Toimprove its a mmonium and phosphate removal effi ciency t hrough thetombart hi te La modi fic ation.The ph osphate removal effi ciency wasi mproved under the conditi ons of la ntha num conc entra tion at0.5%, p H10,r eacti o n ti me24h.soli d-t o-liquid r ation at1:5. Re sults showe d t hatre moval r ate of a mmoniu m a nd phos phate were90%,95%res pect ivelyunder the pH4~8, and t he dosa ge of10g/L. The adsor p tion proc ess o fammo nium and phosphate was in accord wit h ps eudo-se cond-order kineti cmodel. The equili br ium a dsorption data were fitted t o La ngmuir isot her msand the maximum adsorption capacity of ammonium and phosphate were3.94,1.65mg/g re s pectively. |
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