i live in the midst of the city and i was wondering if anyone has some ideas on "filtering/removing/de-ponging" fumes being evacuated from a fume hood?

i dont use an aspirator for enviro reasons (plus i dont have one )-but-if you use an aspirator in a closed system(loop via a bucket/drum) how well does it 'de-pong'

You'll need an aspirator of some sort, this was posted on the Hive long ago:

Following is a description of a simple gastrap:

Simple Trap for Obnoxious Vapors

In many syntheses large volumes of HCI, HBr, oxides of nitrogen, etc. are evolved, and in crowded laboratories it is sometimes a problem to provide adequate hood space. The drawing illustrates a simple device which ecoomically answers the question of vapor disposal. It can be readily constructed from ordinary laboratory equipment. It dispenses with the usual alkali trap or specially made glass traps, and at the same time frees hood space for other experiments. A 500-ml.suction flask is provided with a 2 hole rubber stopper and two 8-mm. glass tubes are inserted. The bent one goes almost to the top of the inverted flask. and the other one projects about 4-5 cm. above the side-arm. Usually a condenser is employed in such experiments and a stopper provided with a short bent tube is inserted into the upper end of the condenser, this tube being connected with the bent glass tube of the trap by means of a short length of rubber tubing. The exit water from the condenser is led into the side-arm of the suction flask and the straight tube is connected to the sink. The current of water effectively removes the vapors. It is obvious that a large side-arm test tube, a distilling flask or a wide-mouth bottle provided with a 3-hole stopper can be substituted for the suction flask.
Additionally, it is also obvious that if one wished to trap a larger amount of gas, this device could be scaled up easily using a 5 gallon plastic jug with a  plastic tube attached to the side. Devices of this type have proven effective in concealing the most obnoxious reactions from observation.

I always liked Strikes idea of building a small fume hood;













A cheap exhaust fan could be bought and connected to either a purchased or home made carbon filter. One such as this could easily be mounted to the top of a fume hood (or underneath) and the excess vented straight out side. Nearly every 420 website has DIY carbon filter plans that would work well, also a custom one could be easily and cheaply made to fit the top of a home made fume hood.





There are also products from hydro shops that you can add to the carbon filter that can further mask smells. Like orange mate air freshners, ONA odour neutralizing agents. Using those with the gas traps or other types of traps that will capture some of the compound further reducing the smell produced.

hi folks i've been away for a few weeks and havent had the time /opportunity to reply etc--lugh please dont assume i 'cant be bothered/dont look etc' as i have mentioned before i cant open djvu files on the system am using 98% of the time  -but i do appreciate the ref's-- i am 'a newbie' in many ways, BUT i dont want to be 'spoon fed' --i thought the whole idea of forums like here ARE for sharing info/knowledge and i.e the stuff many wasps have shared with me HAVE saved me a LOT of time looking thru "piles of files" and consequently 'lots of time'guys i'm playing "catch up" BIGTIME and i figure its gonna take me most of this year to come 'up to speed' with my learning and understanding,,,but i'm pedalling as fast as i can
   (also the last four times i have tried to post something,,the system i am using has 'crashed' and i lost some rather long and comprehensive posts :'( ...hmmmm?)
 
as for the naf juan, as usual you provide "THE" goods, and as ALWAYS it is GREATLY appreciated

 and vesp a lot of my questions at the moment are basically 'hypothetical' coz i am trying to "look and learn" before i go and fuck things up,,,(which i am pretty confident i CAN do ) two of those posts were in reply to some of the questions yyou have asked me in other threads,,but sadly they were lost (its weird but EVERY time this has happened i was usine 'mozilla ff' hmmm?) so for now i am sticking with 'IE' but matey i will be trying again to ansa your q's as best i can,,thanx for being so patient,,you know i dig this site,,
  btw,,would you mind if i was able to copy the picture of the wasp nest in the funnel to screen print on some shirts? i would send you one for free and would make them available to other members for cost plus postage--i reckon it would look great,,and in a way,,anyone familiar with this nest,,would recognize a 'felllow wasp'
 so thanx again to all and any of the wasps who have been kind enough to take the time to help me,,you know who you are
 more coming now on other threads,,
cheers all,,hypno