BMP testingEnergy crops and whole-crop plants (WCS)single study (5 samples)

Energy dock — BMP: 5 studies, weighted mean 271 m³ CH₄/t VS

Energy sorrel (Rumex, variety Uteusha) is a perennial plant grown for biomass, considered as a biogas substrate. In the dataset it appears in several records from one study.

CH₄ ≈ 52 % (estimate)

Published 10 April 2020Updated 29 October 20263 min readFeedstockData Editorial Team

Illustration: FeedstockData (AI, Google Gemini)

Weighted mean: 271m³ CH₄/t VS
Range: 187–297m³ CH₄/t VS
Records: 5single study (5 samples)
Publications: 1source
Temperatures: 37 °Cof the test

Methane in biogas

≈51–54% CH₄

Medium methane content · ≈ 5.2 kWh/m³ of biogas

estimate from the substrate type The collected studies contain no measurement. The interval follows from the approximate composition (carbohydrate-dominated (no protein or fat characteristics)) and the yields of compound groups according to FNR.

How we calculate it and what the zones mean

Rating for biogas plants

not rated — editorial rating for biogas plants

Not rated: no dry matter or volatile solids in the data. We calculate the rating when the dry matter and volatile solids of the material are known.

Editorial rating per the methodology

Add to the co-digestion calculator CSV data

BMP curves from 5 studies

Weighted mean Individual records

Dashed lines are a model curve (first-order kinetics, B(t) = B₀·(1 − e^−kt)); the end point comes from the publication. All curves are model curves.

Cumulative methane production over the test [m³ CH₄/t VS]. The thick line is the weighted mean of all records (271); dots mark the end values given in the publications. Point at the chart to read values; click a legend item to hide or show a record.

Records and sources

Download CSV

Source	BMP m³ CH₄/t VS	Temperature	Sample	Curve
Mast et al. (2014) · 1 DOI	187	37 °C · mesophilic	energy dock	end point (model curve)
Mast et al. (2014) · 2 DOI	289	37 °C · mesophilic	energy dock	end point (model curve)
Mast et al. (2014) · 3 DOI	290	37 °C · mesophilic	energy dock	end point (model curve)
Mast et al. (2014) · 4 DOI	294	37 °C · mesophilic	energy dock	end point (model curve)
Mast et al. (2014) · 5 DOI	297	37 °C · mesophilic	energy dock	end point (model curve)
Weighted mean	271	arithmetic mean 271, SD 47

Typical composition

Dry matter (DM): 15% (range 9–28)

Median and range of the determinations reported in the publications behind this substrate's BMP records (read from: MY-D); dry matter: 5 determinations, volatile solids: 0 determinations.

Sources: Mast et al. (2014).

The composition of the raw material varies between batches — for plant calculations use an analysis of your own sample. The calculator inserts typical values automatically.

Process properties

seasonal
fibrous
editorial classification

Advantages

Methane potential in the database: weighted mean 271 m³ CH₄/t VS (median 290; range 187–297; 5 records from 1 sources).
Sorrel (Rumex schavnat) in a field experiment: SMY fell during the season from 0.297 to 0.187 Nm3/kg VS (Mast 2014).

Drawbacks and risks

Yield depends strongly on the harvest date (Mast 2014).

Co-digestion — what to combine it with, what to watch out for

combines well
group: Animal excreta (slurry, manure, poultry litter)
Co-digestion with excreta (slurry/solid manure) is the standard arrangement for plant biomass: they supply alkalinity and microflora.^[1][2]

Dosing

No source-based dose limits.

Sources of the process data

The co-digestion calculator will assess a specific mixture containing this substrate.

What it is and where it comes from

Energy sorrel (Rumex patientia × R. tianschanicus), variety Uteusha, was bred in Ukraine and is sometimes grown in Poland as a perennial energy crop. It gives several cuts per season, and the biomass yield can be large. The dataset contains several records from one study in which material harvested at different dates was examined, under mesophilic conditions.

Properties relevant to digestion

Sorrel biomass is succulent, with a high water content in the young stage, and as it matures the share of lignified stalks rises. Plants of the genus Rumex contain oxalates, which can bind calcium and in large quantities affect the course of digestion, although at typical shares in a mixture the effect is not considered key. Ensiling is possible, and the material requires chopping. There is more protein than in typical grasses, which lowers the C/N ratio, but increases the risk of ammonia release at a large dose.

How to read the spread of results

Several records come from one study, and their variation mainly reflects harvest date and year. They therefore do not capture differences between laboratories, plantations and soil conditions. The result is also affected by plantation age, fertilisation, the form of the material (green forage, silage) and chopping. A common test protocol across the whole series means that the records are internally consistent, but may be difficult to transfer to other conditions.

In biogas plant practice

Energy sorrel is a niche crop, of interest to farms looking for perennial plants to supplement their feedstock base. It is harvested with a forage harvester and ensiled, and in the mix treated like other plant silages, with control of ammonia and process stability. Profitability depends on yield at local sites and on the costs of establishing the plantation. Before deciding, your own BMP test and a dosing trial are recommended. Because the dataset contains one study, and the plant is not widely grown, the data should be treated as a preliminary reconnaissance. Only your own BMP test and a trial crop will show how the material behaves in a specific plant and how it yields at local sites. It is also good to record cutting dates and yields from the start.

Methodology in brief

BMP is the amount of methane obtained from volatile solids (VS) in a batch test, given in m³ CH₄ per tonne of VS (numerically the same as NmL CH₄/g VS in the publications) and converted to normal conditions (0 °C, 101.325 kPa). The weighted mean gives each publication a total weight of 1, split equally between its results for the substrate — a paper testing twenty varieties does not outweigh a paper with a single sample. In inter-laboratory programmes the unit is the laboratory (total weight 1), and within it the weight of a test grows with the number of bottles (replicates). Results after pretreatment (e.g. thermal, chemical, enzymatic) are shown separately and are not included in the mean.

Solid lines are curves measured in the tests. Where a publication gives only the final result, we draw a first-order kinetic model, B(t) = B₀·(1 − e^−kt): only the end point comes from the publication, and the shape of the curve serves purely as visualisation — do not read the production on a particular day from it. For this substrate k = 0.085 d⁻¹ was assumed (median of rate constants k reported in the sources and/or fitted to the mean measured curves).

The statistics describe the spread of published results — a descriptive compilation, not a meta-analysis or a guarantee of plant yield.

Full methodology and correction policy

Bibliography

Mast, B.; Lemmer, A.; Oechsner, H.; Reinhardt-Hanisch, A.; Claupein, W.; Graeff-Hönninger, S. (2014). Methane yield potential of novel perennial biogas crops influenced by harvest date. Industrial Crops and Products 58, 194–203. DOI: 10.1016/j.indcrop.2014.04.017 DOI

All sources of the site: bibliography.