SODIS in Winter - Lab Report Example

The plastic bottles were then shaken for a period of twenty seconds followed by filling the bottles completely. One bottle was directly taken to the lab for the initial E.Coli count of the available raw water sample. The remaining eight bottles were labelled as 1, 1F, 2, 2F, 3, 3F, 4, 4F with the numbers on the bottles corresponding to the number of days of heat and sunlight exposure. In this case, F was used to mean foil. Then the F bottles were all wrapped in a foil in ensuring that the samples were prevented from receiving sunlight and thus limited to receiving heat.

After being exposed in the heat in the first day, the one and 1F bottles were brought to the lab for purposes of carrying out a E.Coli analysis. This procedure was repeated for the second, third and fourth subsequent days of exposure. In this experimental set up the control experiments were water without the UV-A exposure or sunlight and water without heat or solar reflector. In essence, this was just but raw water sample Observations In this experiment the observation were noted following a certain chronological order.

In the first day in which the experiment was carried out outside for a period of 2 hours and thirteen minutes, starting at 12.17pm extending to 2.30 pm with the conditions of the day characterized by a cloudy sky with light snow furries along with a little sun shine, it was such that from 1pm to13:40pm, a cling wrap was inserted on the opening in helping prevent snow from interfering with the solar reflector. It was observed that the cling wrap inside surface steamed up necessitating the removal of the cling wrap.

In day two in which the experiment was carried out inside and behind glass given that snows were falling outside. In this second day of experiment, the experiment was carried out starting at 12.28 pm extending to 4.40 pm conditions being such that there was no direct sunlight or SNOWING. On day three of the experiment, the experiment was carried out behind glass. From 11 am extending to 1 pm, there was a cloudy sky. However, the experiment was not facing the sun’s direction since the direction of the sun could not be determined.

From 1 pm extending to 1:30 pm light rain was observed and the experiment was halted at 3.30pm following heavy downfall. On the last day of the experiment, which was on day four, the experiment was carried out from 12:30pm extending to 4:30pm and it was behind glass given that it was slightly snowing outside. As was observed on this day, the bottles had a green/brown colouring sediment and was not attached on the plastic bottle, though as observed it was somewhat denser than water. Results The data wereplotted in table 1 Table 1showing number of E.

Coli (in Colony-Forming Units or CFU) and the exposure time (sunlight and heat) for the SODIS Method Experiment E.Coli J+1 J+2 J+3 J+4 Traite UFC/100ml 202 95 96 18 Controle UFC/100ml 427 418 205 241 Discussion According to the graphical representation of the experimental results in F1 above, it was clear that the heat treatment group had fewer E. Coli relative to the raw water sample (control group). More evidently, the sunlight, as well as the treatment group h