What happens to yard waste and biowaste in Germany? This Sankey diagram from a 2014 PowerPoint presentation titled ‘Flächendeckender Ausbau der Biotonne in Deutschland’ by Peter Krause and Rüdiger Oetjen-Dehne (u.e.c. Berlin) shows how these flows were distributed.

In 2012 there were 14.5 mio. tonnes of yard waste andd 6.6 mi. tonnes of bio waste (kitchen/food waste) were disposed of in Germany. Much of it was collected and treated or – such as in the case of yard waste – composted (7.8 mio. tonnes).

In addition to the absolute quantities the labels along the Sankey arrows show the average per inhabitant (kg/E, a).

A large potential is still in bio waste (orange-coloured arrow) being disposed of in regular household waste (“Restabfall”). Calls for separate collection of bio waste for energy recovery are being made.

Rytec, a Swiss-based consulting firm, is the author of a 2011 report that compares 29 waste incinerators in Switzerland in regard to their energy flows.

The report ‘Einheitliche Heizwert- und Energiekennzahlenberechnung der Schweizer KVA nach europäischem Standardverfahren’ (translation: Uniform heating value and energy indicators calculation for Swiss waste incinerators according to European standard method) was comissioned by Swiss Environment Agency (BFU) and Swiss Energy Agency (BFE).

The annex contains 29 Sankey diagrams like the following:

All waste incinerator Sankey diagrams are structured similarly, allowing direct comparison of efficiency and energy output mix. Data is for 2009.

The first diagram is for KVA Basel (waste incinerator Basel), the second for KVA Oftringen (waste incinerator Oftringen, Aargau). Basel is much larger (incinerated waste with energy content of 710 GWh in 2009) and serves an urban area. Oftringen is smaller and seems to be more of a regional waste incinerator (incinerated waste with energy content of 237 GWh in 2009).

Basel apparently sells off the heat to the district heating system or neighbouring industry (yellow arrow ‘Wäremexport’) and converts only a small fraction to electricity. Oftringen on the other hand sells off electric energy (43 GWh) with apparent losses (grey arrow 122,5 GWh).

A lot more to discover when comparing these two (and the other 27) Sankey diagrams.

Yesterday it became known that the European Commission would shelve their circular economy package of waste, recycling and incineration laws for now, in favour of an even more ambitious legislation to be presented by end-2015 (read here or here).

That led me to browse tweets using the hashtag #circulareconomy, and I ended up unearthing two nice Sankey diagrams…

The first one is by WRAP UK, showing the EU-27 material flows estimated in 2020. This is not for a specific type of material, but all material.

Flows are in million tonnes, with the 2020 values in blue, and the current (2010) figures in brackets below for comparison. There are three nodes: ‘Direct Material Input’, ‘Domestic Material Consumption’ and ‘Waste’. Unfortunately the size of the node icons is too large, and the flows are difficult to see. But still, this is a nice idea!

The main message is that in comparison to 2010, Europe could have 350 million tonnes of recycled material in 2020. Check out these Sankey diagrams by WRAP UK that basically convey the same messsage, but are less infographic.

Another Sankey diagram I found when browsing through the tweets was this one below. The title of the diagram is “How circular is th UK?”.

I found it in a blog post ‘Designing Out Waste Consortium’ by Ramon Arratia on Interface’s Cut The Fluff blog on sustainability, but it is originally from this Green Alliance blog post by Julie Hill.

No values shown along the flows in this Sankey diagram, but neatly shaped circular flows. The question raised in the title is answered prominently with the message that 19% of the material in the UK is led in a loop (pink flow).

Energy flows in a waste incinerator facility of MVR-HH (‘Mullverwertung Rugenberger Damm’) in Germany are depicted as Sankey diagram on their website.

Flows are for 2013 in MWh per year (MWh/a). The hot red area is the boiler (‘Kessel’), followed by the turbine. Almost half of the energy is used as process steam and for district heating (‘Warmwasser Neugraben’). Losses branch out vertically.

Consulting firm Rytec analyzes energy and heat utilization level of Swiss waste incineration plants and visualizes the processes using Sankey diagrams.

This Sankey diagram from their website is a simplified view and offers no details as to the actual figures. More detail can be found in this project summary (PDF).

Diagram labeled in German, but thanks to my friend Google Translate, I can identify ‘heating’, ‘boiler’, ‘energy conversion’ and ‘flue gas losses’. Orange streams to the top are losses.

From this presentation by Berlin-based consulting firm UEC comes the below Sankey diagrams on sorting of waste in a waste treatment facility in 2003.

No absolute values are given, only a percentage breakdown of the waste that is being treated.

After the first steps, the drum sieve (‘Siebtrommel’) splits the waste flow in three main fractions based on the size of the shreddered waste. The blue arrow are unsorted remains, the colored ones are recovered materials.

Only apparent flaw of this Sankey diagram is that the arrow labels show ranges for values. An accompanying table in the presentation has the minimum and maximum sorting quotas. Not clear which value was used for determining the arrow widths.

Yale School of Forestry & Environmental Studies and The Connecticut Energy & Environmental Protection Agency have conducted a study on waste flows titled ‘Unlocking the Value: Transforming the Connecticut Materials Economy’.

The study features two Sankey diagrams that show the present situation (2010) and a an alternative scenario, where much of the materials are recovered.

This is the current situation in which only 25% of the 3.16 Mt of waste (Building C&D Waste not considered) are recycled.

The authors explain that

“Each year Connecticut residents and businesses generate more than three million tons of munici pal solid waste (MSW, or “regular trash”). Currently existing recycling and reuse programs capture a portion of the value of Connecticut’s waste, while waste-to-energy facilities process and recover energy from most of the MSW that is not recycled. With our recycling infrastructure underutilized, and resource recovery facilities at capacity, there is vast potential to transform our management and processing systems to further unlock the economic potential of waste.”

The optimized scenario with much increased recycling of materials (almost 80%) is shown in this diagram:

Connecticut is looking into the environmental and economic benefit of a recycled materials econonmy.

via Talismark blog

While some of you might think of their favourite lunch time snack, in the UK the term WRAP refers tp the ‘Waste & Resources Action Programme’, an independent not-for-profit company.

WRAP now presented their vision for a circular economy in the United Kingdom by 2020, using Sankey diagrams:

The material flows for the baseline year 2000 are shown in a first diagram here:

In that year, apparently, 212 Mt of material were disposed of as waste (orange arrow), while only 47 Mt were recycled.

The situation in 2010…

… and the vision for 2020 (from this page):

The goal is to use less input materials, to reduce waste output and to recycle 3/4 of the materials.

See diagrams in high resoultion directly on their website.