The Morning after the night before

Tuesday 27th November

In the morning we went back to site and surveyed the situation.  The tanks now had had the following volumes of sludge put into them:

1 – Filter bed with metal roof: 580L

2 – Filter bed with plastic roof: 510L

3 – Filter bed with thatch roof: 560L

4 – Flat bed with metal roof: 490L

5 – Flat bed with plastic roof: 490L

6 – Flat bed with thatch roof: 490L

The reason for the differences is the assortment of containers the material was delivered in.

We took the roofs off while I prepared the sampling materials.  We had screw top plastic jars, plastic spoons, and gloves.  I labelled up each of the jars and set them out on the sides of each of the tanks.  Suman and I put some plastic gloves on, and started spooning in the sludge into each jar.  The spoons were discarded after use and Opel collected them all in a rubbish bag.  At this point the smell really wasn’t too bad, it was more a revulsion at the collecting part!  The sampling process took about an hour.

Me at the laboratory desk preparing the sampling equipment

Setting out the jars - three samples were taken from each bed

Hopefully this will be enough to test

Taking a sample from the drainage pipe

 We wiped down all the jars with antiseptic wipes just to clean off any traces of spills or splashes, and packed them with ice in a coolbox and bag, making sure they would remain upright for the journey into Dhaka.

Packing the samples on ice to take to Dhaka

Before the roofs went back on, I scurried around with my laptop, and downloaded information from the sensors.  I also tried to use the moisture sensor I’d brought, but the batteries had run down, and we had to get some replacements from town.  I wasn’t very convinced by the readings I got – one bed may have been clearly more liquidy than another, but the sensor was saying that it had a lower VWC (volumetric water content).  I suspect this may be because they are all >85% moisture and it’s confusing the sensor.  Once they dry out a bit, I’ll re-try.

I spent the remainder of the afternoon creating some pretty graphs of the initial results and trying to send a few emails on the rather limited internet connection here.