Biomedical Engineering Reference
In-Depth Information
Microbes
Microbes
FIGURE 21.1
Schematic.illustrating.how.VOCs.are.converted.by.bacteria.into.CO
2
.and.H
2
O.
more.area.than.plastic.media.and.70.times.more.than.a.traditional.sand.ilter..Water.low.
through. the. porous. ceramic. media,. either. in. aggregrate. or. monolith. form,. is. more. than.
ive.times.higher.than.that.of.a.sand.ilter.for.a.given.pressure.drop.
Bioremediation.is.commonly.used.to.remove/convert:
•. Ammonia.in.aquaculture,.industrial,.and.on-site.wastewater
•. Nitrites.and.nitrates.commonly.found.in.industrial,.aquaculture,.agriculture,.and.
municipal.wastes
•. Hydrogen.sulide.and.volatile.organic.compounds.(VOCs).in.waste.gases.(Figure.
21.1).from.industrial.and.municipal.sources
High. surface. area. porous. ceramics. have. proven. more. effective. than. other. media. for.
these.applications,.requiring.fewer.media.for.equivalent.performance.
21.3 Nanotechnology
Nanotechnology.is.the.manipulation.of.individual.atoms.and.molecules.in.ways.that.cre-
ate. materials. and. devices. having. vastly. different. properties..
Nano
. means. 1. billionth,. in.
this. case. a. nanometer. (nm).. A. nanometer. particle. contains. only. a. few. atoms.. Typically.
nanomaterials.are.less.than.100.nm..For.comparison,.a.virus.is.typically.100.nm.in.size,.
and.a.human.hair.is.70,000.nm.thick.
Nanomaterials.are.available.today.in.the.form.of.activated.materials.like.carbon.or.alu-
mina.
4
.These.are.materials.with.high.surface.areas;.however,.because.of.the.ine.pores,.not.
all.of.the.water.can.easily.reach.the.active.surfaces.and.ine.pores.are.easily.plugged..This.
highlights.a.major.challenge.in.using.nanomaterials—their.small.size..These.ine.particles.
or.ibers.cannot.just.be.added.to.drinking.water,.but.rather,.they.must.be.incorporated.into.
iltration.media.in.ways.that.allow.for.the.contaminants.in.water.(or.waste.gases).to.readily.
