Zero　emission　of　wastewater　from　coal-fired　power　plants　(CFPPs)　is　one　of　the　pathways　for　cleaner　electricity　production.　It　is　expected　that　low-cost　and　reliable　zero　liquid　discharge　(ZLD)　of　flue　gas　desulphurization　(FGD)　wastewater　will　be　achieved　by　applying　the　forced　circulation　multi-effect　distillation　and　crystallization　(FC-MEDC)　technology.　In　the　present　work,　different　FGD　wastewater　ZLD　processes　were　compared　in　terms　of　energy　consumption,　economic　cost　and　environmental　impact.　The　results　suggest　that　the　levelized　cost　of　water　(LCOW)　could　be　reduced　by　the　integration　of　pre-concentration　and　waste　heat　utilization　with　FC-MEDC.　Typically,　the　LCOW　could　be　reduced　by　9.5%　and　28.8%　in　reverse　osmosis　(RO)　and　flue　evaporation　(FE)　incorporation　scenarios,　respectively.　The　implementation　of　crystal　seed　technology　in　the　FE-assisted　FC-MEDC　system　significantly　decreased　the　LCOW　by　45.4%　for　chemical　pretreatment　cost　reduction.　A　further　parametric　study　was　performed　to　examine　the　influence　of　key　variables　on　the　LCOW.　Overall,　a　comprehensive　investigation　of　FC-MEDC　treatment　of　FGD　wastewater　was　performed,　resulting　in　cost-effective　design　of　a　thermal　ZLD　process　with　a　minimum　LCOW　of　5.60　$/m3.　Sensitivity　analysis　was　conducted,　revealing　the　influence　of　market　factors　on　the　economic　viability　of　different　schemes.　In　addition,　environmental　analysis　indicates　that　the　greenhouse　gas　(GHG)　emissions　from　the　FGD　wastewater　ZLD　processes　ranged　from　38.1　to　86.8　kg　CO2-eq/m3　in　different　scenarios　and　representative　regions,　and　could　be　notably　reduced　by　51.7%.　The　methodology　and　results　are　useful　for　wastewater　ZLD　process　screening　to　minimize　costs　and　environmental　impacts.　©　2020　Elsevier　Ltd