Chillin' and Landfillin'

In the past three days since my last blog post, we have completed our first project and visited a sanitary landfill as another one of our technical visits!  Having the first project done is a huge relief and now I can continue to focus on the work ahead.  Overall I feel as though our group did well on the presentation and report and I'm totally stoked about it.  I loved my group but I'm also looking forward to working with new people and getting to know everyone a bit better.

On Tuesday the group and myself visited a sanitary landfill and co-generation plant operated by Ecoserdiana.  This was the first time that I have ever visited an operational landfill so it was extremely cool to see the work that was going on.  The area was comprised of six different landfills the majority of which had been closed and one of which was in use.  The one in use is specifically for designated waste as well as the fly ash and bottom ash from the waste to energy facility that we visited earlier in the trip.  The landfill no longer accepts municipal solid waste, only the designated waste and ash.  I found the magnitude of the total area to be immense; much larger than some of the examples I remember doing in class this past semester.  I also found it interesting to note that the leachate that they produce is sent to the waste water treatment plant that is operated by the same entity that operates the waste to energy facility (Of which the ash is sent to the landfill).  This is a very symbiotic relationship that seems to be somewhat sustainable, at the very least financially.  It was also interesting to note that the current landfill was being built upon an existing MSW landfill that had been closed.  This is an efficient use of space.  The landfill also utilizes horizontal biogas collection pipes as well as joint collection pipes located at the bottom.  The joint collection pipes collect both leachate and biogas by means of gravity and vacuum respectively.

When we went to the co-generation plant, we saw that the amount of methane that comprised the total biogas was roughly 55 percent.  This is a pretty good amount of biogas for a landfill, especially upon closer of the MSW section.  Beyond the biogas plant, there was also a solar farm.  It was interesting to note that the solar farm produced 1/4 the amount of electricity but only took up 1/20 the amount of space.  This fact only highlights that biogas generation should not be looked at as a means to an end, but a supplement to other forms of energy.  Beyond using the combustion of methane for electricity, the plant also used the heat from combustion, hence the term, "co-generation".  By doing this, the process of using methane is 90% efficient.  Overall, the visit was extremely informative and provided finer detail to accompany what I have learned in the classroom.  The trip also allowed me to see the co-generation plant and learn about how the methane is utilized as efficiently as possible.

Below are some pictures of the landfill:

Closed landfill used for designated waste.  The reason it is green as opposed to dried out is because of the impermeable layer on the top, through which water cannot percolate.  

 A shot showing various equipment as well as the working face of the open landfill used for the disposal of fly ash, bottom ash, and designated waste.

   Another shot of the landfill and the land being worked on next to it on the other side of the impermeable berm.