Combustibility of biomass from wet fens in Belarus and its potential as a substitute for peat in fuel briquettes

Peatland drainage has caused enormous environmental problems at global scale; in particular, ongoing greenhouse gas emissions and soil degradation. In Belarus, which is rich in peatlands and a hotspot of emissions from drained peatlands, several thousand hectares have already been re-wetted but are not used productively. Moreover, vast areas of wet (undrained) peatland that are designated for nature conservation are in need of mowing and biomass removal. Plants such as common reed (Phragmites australis), reed canary grass (Phalaris arundinacea) and sedges (Carex spp.) which frequently dominate these areas could be harvested and used as fuel, potentially as a substitute for peat. In this study we analysed the yield and combustibility of late harvests in March/April 2009 and 2010. The yields of 3.7–11.7 t DM ha-1 were within the range reported from other studies on wetland plants. Concentrations of Cl, S, N, P, C, Ca, K, Mg and Na, as well as water and ash contents, indicated similar or better combustibility when compared to other straw-like (graminaceous) plants such as Miscanthus. The full replacement of peat fuel by biomass from wet peatlands in Belarus would require an area of 680,000 ha, i.e. 'only' half of the peatland that has been drained for agriculture

Life cycle assessment of biomass production from drained wetlands areas for composite briquettes fabrication

The area of wetlands after peat mining in Belarus is about 190,000 hectares and once peat harvesting has ceased it is impossible to grow any cultural plants for some years. One of the perspective directions is rewetting wetlands after peat extraction that stimulate vegetation of natural grass, like reed, rush and others which are growing in natural conditions. The grass biomass may be used for energy purpose, in particular for composite briquettes fabrication, which contents in 50 % from grass and 50 % from peat. The LCA method based on the standards series ISO 14040 was used for evaluation of environmental impact of growing and production of composite briquettes from wetland biomass. The goal of LCA was comparison two scenarios of biomass production for composite briquettes. Product system B (PSB) based on biomass harvesting with simultaneous shredding and product system A (PSA) based on biomass mowing, raking for drying and bailing. The basic LCA impact categories were: climate change, acidification, photo oxidant formation, eco toxicity and human toxicity. The product system A (mowing and baling biomass) achieved better results in 3 categories out of 5, and especially eco toxicity and human toxicity. And if for climate change the indicator results for both systems were close, for acidification, eco toxicity and human toxicity PSB systems impact was significantly higher to compare to PSA. It may be explained by peat using for biomass drying in product system B. The contents of SO2 and Hg in the peat in several times higher to compare to diesel and gas, while PCB and GCB are contained only in the peat

Production and Energetic Utilization of Biomass from Rewetted Peatlands

Among other biomass fuels, common reed (Phragmites australis) is considered as a promising source for Bioenergy. Within the project “ENIM” partners from science, industry and agriculture develops an integrated process to use common reed from rewetted peatlands for the combined heat and power generation in a biomass CHP plant. Ecologically compatible solutions of the reed production and harvesting will be investigated, the necessary logistic will be developed and finally the process of the power plant will be adapted for the commercial utilization of reed as fuel. The project is supported by the German Federal Environmental Foundation (DBU) and will contribute to a sustainable and ecological land use and an environment friendly energy economy

Towards large-scale paludiculture: addressing the challenges of biomass harvesting in wet and rewetted peatlands

Peatland drainage causes peat degradation, which results in high greenhouse gas emissions and ongoing subsidence of the ground surface. To avoid further land degradation, the rewetting of peatlands is essential. The new land use concept of paludiculture - the use of wet and rewetted peatlands for agriculture and forestry - now offers possibilities for landowners and land managers to continue using these sites under wet conditions. But new challenges arise due to the limited bearing capacity of wet soils, which restricts accessibility for machinery. Whilst many site-specific technical solutions for harvesting on wet peatland are available, it remains unclear whether current machinery is suitable for use in the large-scale implementation of paludiculture. Repeated crossings of the same ground can easily disturb the upper peat layer and cause serious problems for the removal of biomass. In this article we present available machinery and approaches to biomass harvesting; and explore how the number of transport runs required for biomass removal varies with productivity of the site, cargo capacity and working width of the harvesting machinery. The results are used in a discussion of logistics and infrastructure requirements to facilitate the implementation of paludiculture. Whilst there is still considerable scope for improvement of harvesting technologies, our results show that a peat-conserving harvest from wet and rewetted peatlands is possible with adjustments to harvesting technique, logistics and site infrastructure

Combustibility of biomass from perennial crops cultivated on a rewetted Mediterranean peatland

A paludicultural experiment was conducted in the Massaciuccoli Lake Basin (Tuscany, IT) to test this restoration strategy to reduce water eutrophication and subsidence phenomena of peat soils. The species tested were three perennial rhizomatous grasses (PRGs), Arundo donax, Miscanthus xgiganteus, Phragmites australis, and two woody crops managed as short-rotation coppice (SRC), Populus x canadensis 'Oudemberg' and Salix alba 'Dimitrios', each of these species promising high productivity under wet conditions. The study aimed to test the combustibility of their harvested biomass as a function of crop age and harvest date. Parameters important for combustion and exhaust gas emissions were analyzed: ash content, concentration of chlorine (Cl), sulfur (S), nitrogen (N), phosphorus (P), carbon (C), hydrogen (H), calcium (Ca), magnesium (Mg), potassium (K) and sodium (Na). Results indicated that the SRC crops appeared the most suitable for combustion. A general improvement in biomass quality with crop age was found for all crops tested, showing a significantly lower concentration of critical elements (Cl, N, S) and ash content in the 3rd year after planting. The biomass quality of PRGs was not significantly improved by a delayed harvest in February, as successfully practiced in northern Europe. In general, although concentrations of the most important critical elements were higher than expected for all crops, the calculated higher heating values were promising. Combustibility performances could be improved by finding an optimal mixture of SRC and PRG biomass. (C) 2016 Elsevier B.V. All rights reserved

Энергетическое использование биомассы из заболоченных торфяников / M. Барц, Г. Кабенгеле, A. Брандт, В. Вихтман, М. Венцель, С. Вихманн, К. Омке, Т. Дамс, Л. Борг

The global biomass demand for food and fodder as well as for energy production will continuously increase in the near future, leading to increasing pressure on land use. For example, agriculture and forestry on drained peatlands will substantially change the physical, biological and chemical soil properties and results in peat degradation, accompanied by huge emissions of greenhouse gases. Peatlands cover an estimated area of ca. 400 million ha, equivalent to 3 % of the Earth’s land surface [23]. According FAO only 15 % percent of peatlands are drained and used for agriculture, grazing, peat mining and forestry, especially for bioenergy plantations, but causing almost 6 percent of total anthropogenic CO2 emissions and almost 25 percent of the GHG emissions from the entire land use [10]. Since November 2018, HTW in collaboration with Greifswald University started a new and innovative research project, studying the production of biomass on wet peatland sites and the optimization of the thermal utilization of such biomass sources in small and medium scale applications, e.g. household systems and centralized heating plants for communities. The project is therefore focused on an alternative opportunity of using peatlands for bioenergy production, avoiding soil degradation and reducing fossil fuel based GHG emissions by replacing such fuels. Several peat forming plant species such as Common Reed, Reed Canary Grass Sedge species can be produced on rewetted peatlands. Common Reed (Phragmites australis) e.g. grows rapidly and the annual yields will reach under Central European conditions between 3.6 up to 43 t dry matter per ha and year (depending on water level, nutrient availability and pH values) [31]. The heating value of reed (17.7 MJ/kg) e.g. is remarkable and comparable with Miscanthus. Modified conventional agricultural technologies are suitable to harvest, compact, transport and store the reed and well established conversion technologies as e. g. boiler technologies for straw can be used for the utilization of the reed biomass. The presentation and the respective publication of the related paper will introduce the first results of this research project, including the results of measuring campaigns, carried out at a 800 kW heating plant for community heating in Malchin (Mecklenburg Western Pomerania) during February/March 2019.В ближайшем будущем мировой спрос на биомассу для призводства продуктов питания и корма, а также энергии будет непрерывно расти, что приведет к увеличению нагрузки на землепользование. Например, сельское и лесное хозяйство на осушенных торфяниках существенно изменит физические, биологические и химические свойства почвы и приведет к деградации торфа, сопровождаемой огромными выбросами парниковых газов. Торфяные угодья занимают около 400 млн га, что эквивалентно 3 % поверхности Земли [23]. По данным ФАО, только 15 % торфяников осушаются и используются для сельского и лесного хозяйства, выпаса скота, добычи торфа и особенно в качестве биоэнергетических плантаций. В результате этой деятельности количество выбросов составляет 6 % от общих антропогенных (CO2) и почти 25 % выбросов ПГ от землепользования [10]. С ноября 2018 г. HTW в сотрудничестве с Университетом Грайфсвальда начал новый инновационный исследовательский проект, посвященный изучению производства биомассы на заболоченных торфяниках и оптимизации термического использования источников биомассы в малых и средних проектах: бытовых системах и централизованных отопительных установках. Проект сфокусирован на альтернативной возможности использования торфяников для производства биоэнергии, предотвращения деградации почвы и сокращения выбросов парниковых газов на основе замены ископаемого топлива. На повторно заболоченных торфяниках можно выращивать несколько видов таких торфообразующих растений, как обыкновенный тростник, канареечник тростниковидный или осока. Тростник обыкновенный (Phragmites australis) быстро растет, а ежегодный урожай в среднеевропейских условиях может достигать от 3,6 до 43 т сухого вещества на гектар в год (в зависимости от уровня воды, наличия питательных веществ и значений pH) [31]. Теплотворная способность тростника (17,7 МДж/кг), например, сопоставима с мискантусом. Модифицированные традиционные сельскохозяйственные технологии подходят для сбора, уплотнения, транспортировки и хранения тростника. Хорошо зарекомендовавших себя технологии переработки, например, теплотехнику для соломы можно использовать для утилизации тростниковой биомассы. В отчете и соответствующих актах представлены итоги исследовательского проекта, включая результаты замеров, проведенных на теплоцентрали мощностью 800 кВт коммунального отопления в Мальхин (Мекленбург, Западная Померания), в феврале и марте 2019 г