Environmental Engineering Reference
In-Depth Information
tABle 12.2 (continued)
jsA/jhA on cleaning a small chemical reactor by experienced and
trained Personnel
Potential Accidents
or hazards
recommended safe
job Procedure
sequence of Basic job steps
.11.. After.1.hour.at.relux,.inert.
the system.and.cool.the.batch.
to.20-25°C.
.11a..If.oxygen.gets.into.system,.
a.ire.can.occur,.sparked.by.
heat.from.the.mechanical.
seal.or.the.agitator.
.11b..Glass.will.break.if.
temperature.extreme.across.
system.is.too.great.
.11a..Close.the.reactor.vent.valve.
and.apply.3.psig.continuous.
nitrogen.pressure.
.11b..Use.city.water.to.cool.
batch..Do.not.use.
refrigerated.water.or.
refrigeration.
.12.. Ground.and.bond.empty.drum.
in.front.of.reactor.
.12.. Static.electricity.can.ignite.
acetone.in.drums.
.12.. Grounding.of.drums.will.
give.zero.static.charge.to.
drum..Bonding.the.drum.to.
the.reactor.will.ensure.that.
the.drum.and.the.reactor.are.
at.the.same.static.charge.
.13.. Drain.material.from.reactor.
into.drum.
.13a..Material.can.spray.out.
of drum.
.13b..Vapors.can.be.present.
.13c..When.reactor.is.drained,.
reactor.pressure.will.be.
relieved.into.drum,.causing.
spraying.of.material.
.13d..Material.being.removed.
can be.contaminated.with.
previously.loaded.material,.
causing.health.risk.
.13a..Material.is.drained.out.
slowly..Protective.shielding.
is.placed.around.bung.to.
protect.operator.
.13b..Local.ventilation.is.brought.
to.drum.bung.to.remove.
any.vapors.
.13c..Once.the.draining.has.
started,.stop.the.nitrogen.
pressure..The.loss.in.reactor.
volume.will.reduce.the.
pressure.to.almost.
atmospheric.by.the.time.the.
reactor.is.almost.empty.
.13d..Check.with.lab.supervisor.
for.proper.PPE.
.14.. Close.drum.and.reactor.
.14a..If.drum.is.too.hot.when.
closed,.drum.will.implode,.
causing.possible.leakage..
lf drum.is.too.cold,.it.will.
warm.up.and.expand,.
causing.possible.leakage.
.14b..Material.can.drain.from.
reactor.to.loor,.causing.
exposure.issues.
.14a..Using.local.ventilation,.let.
drum.equilibrate.with.room.
temperature,.usually.about.
1.hour,.before.capping.
.14b..Close.bottom-out.valve.on.
reactor.
