Landfill Gas Production Rate Quick Calculation Method

The Ready Reckoner or Rule of Thumb Estimate of Landfill Gas Production Rate/Yield

Quickly gain a VERY rough estimate of a landfill's Landfill Gas Production Rate!

For the first considerations of a potential landfill gas production rate, before carrying out a full yield evaluation, for landfill gas utilization projects, you can use the following rules (but always follow this up by doing a full model simulation calculation):

For a 1Mt landfill, filled over the last ten years:

• 1m3 MSW yields 5 – 10 m3/t/y in the first 10 years of emplacement (Environment Agency, 2002)

• 5 – 10 Mm3/y LFG will be generated, which equates to somewhere between 5 x 106/365/24 = 570 m3/hr (lower bound) and, 1 x 107/365/24 = 1140 m3/hr (upper bound)

Two other rules of thumb also apply:

• It takes 1Mt to run a 1MW gas engine.

• A 1MW gas engine needs 530 – 630 m3/hr (depending on its efficiency).

(Source: GasSim and PPC Permitting: Current Practice, Future Practice; Conference Proceedings, Waste 2004, Stratford-upon-Avon, UK, September 2004)

Finally, the smallest EfW schemes which are normally economically viable in the UK, with the benefit from ROCS (or ROSCS in Scotland) are usually 500kW, and based upon a 500kW gas engine. (December 2004)

(Update 2007 – with the availability now of 300kW engines and good prices paid for the power possibly including ROCs, the 500kW minimum has dropped for many sites to 300kW, using these new engines.)

However, this is ONLY a rule of thumb based upon UK MSW, and actual yields will vary greatly. Expert modelling and advice is recommended. Economic circumstances also continually vary. Smaller purpose-designed gas engines and the innovatory use of micro-turbines are among the recent and interesting developments which may reduce the minimum size of EfW schemes still further for some sites.

A further source of  landfill gas production rate information is, also available as follows:

“Theoretical landfill gas yields from complete degradation of the degradable organic matter in household wastes are typically ~370m3/tonne. However, lower yields from landfills are likely because of incomplete degradation in the sub-optimal conditions in most landfills and less than 100% gas recovery efficiency. It is generally thought unlikely that more than 200m3/tonne of methane rich landfill gas could be recovered and, from experiences at gas recovery plants in the USA as well as from other experimental systems, a yield closer to 100m3/tonne is increasingly accepted as the upper practical commercially recoverable yield. In no case, however, has gas recovery been carried out to exhaustion and the above suppositions remain hypothetical.”

The quotation above is taken from the paper; “Enhanced Landfill Gas Production At Large-Scale Test Cells”, D. Campbell*, M. Caine, M. Meadows And K. Knox, of the proceedings Vol1, of the Sardinia '95, 5th International Landfill Symposium, p593.

Related Landfill Gas Articles:

Three Other Methods to Assess Landfill Gas Production Many people have decided to assess landfill gas production Ever since the first gas was seen bubbling from landfills in the 1970s engineers have predicted landfill gas production and recently...

The Importance of LFG Recovery from LFG Production The Importance of Landfill Gas Recovery in Reducing Greenhouse Gas Emissions and the Proportion of Active Landfill Gas Recovery Achievable Over the Life of a Modern Sanitary Landfill Due to...

The Process in Which Landfill Gas is Created For those that ever wondered how the landfill gas to energy process also known as LFGTE works This article takes you through how waste management companies convert naturally occurring landfill...

In a rush? Want to download this page as a pdf file, for future reference? If so, just tell us below, where to send it. This is a free service for all our readers.

Tags: , , ,

2 Responses to “Landfill Gas Production Rate Quick Calculation Method”

  1. Und SonnetDecember 20, 2018 at 3:03 am #

    Cut through the complexity. Freedom from BS RULES! This is what I was looking for. A nice simple starting point for gas output. OK. Just ballpark, but that was all I wanted. Appreciated.

  2. Bert FogleMarch 9, 2019 at 3:00 pm #

    Great tip! Thanks for this quick calculation rule of thumb. Does it still work for commercial waste and for residual waste after the recyclables have been removed?

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: