Properties of Poultry-Manure-Derived Biochar for Peat Substitution in Growing Media.

Peat is considered a contentious input in horticulture. Therefore, there is a search for suitable alternatives with similar properties that can be used for partial or complete peat substitution in growing media. Poultry-manure-derived biochar (PMB) is considered such an alternative. This study aimed at determining the properties of PMBs obtained through pyrolysis at selected temperatures and assessing their potentials to substitute peat in growing media based on the selected properties. The scope included the laboratory-scale pyrolysis of poultry manure at the temperatures of 425-725 °C; the determination of selected physico-chemical and physical properties of the obtained biochars, including the contaminants; and the assessment of the potentials of produced biochars to be used as peat substitutes. PMBs contained less than 36% of total organic carbon (TOC). The contents of P and K were about 2.03-3.91% and 2.74-5.13%, respectively. PMBs did not retain N. They can be safely used as the concentrations of heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinatd biphenyls (PCBs), dioxins, and furans are within the permissible values (except for Cr). Due to high pH (9.24-12.35), they can have a liming effect. High water holding capacity (WHC) in the range of 158-232% w/w could allow for the maintenance of moisture in the growing media. PMBs obtained at 525 °C, 625 °C, and 725 °C showed required stability (H/Corg < 0.7).

The Influence of Poultry Manure-Derived Biochar and Compost on Soil Properties and Plant Biomass Growth.

Promising methods for managing poultry manure (PM) include converting poultry manure through pyrolysis to biochar, which can be used for soil applications. The overall goal of this study was to determine the effects of poultry manure-derived biochar and compost on the soil and growth of cherry tomatoes. The biochar obtained at 475 °C was characterized by a relatively high organic matter content of 39.47% and nitrogen content of 3.73%, while it had the lowest C/N ratio of 8.18. According to the recommendations of the EBC, the biochar obtained at 475 °C demonstrated the most beneficial effects in terms of fertilizing potential. The composting of poultry manure with the straw was successful, and the limit of 60 °C was exceeded, which allowed for the hygienization of the compost. The produced compost and biochar are sanitary safe and do not exceed the limits of heavy metal content. The lowest plant biomass was obtained from growing medium A with 3.6 g wet weight (0.24 g dry weight). The measurements of the height of cherry tomatoes showed that growing media D, E, and F allowed the plants to obtain from 602 to 654 mm in height.

Comparison of Physical and Thermal Properties of Mulching Films Made of Different Polymeric Materials.

The development of polymer materials causes their huge expansion into various areas of everyday life, as well as plant and animal production. Their chemical resistance, good physical properties, and ease of processing result in an increasing use of this group of materials. Outdoor plant production both in open plantations and greenhouses requires various types of materials supporting the vegetation process as well as protecting against pests and weeds. A large group here are various types of materials used for covers of field crops, the main role of which is to prevent uncontrolled and excessive growth of weeds and thus reduce the use of herbicides as plant protection products. Cover films also have other important functions, such as reducing direct water evaporation, better moisture retention around the root system, increasing soil temperature (faster vegetation), etc. However, as always, the problem of introducing new material into agriculture production and the difficulty of its disposal arises. In recent times, farmers' interest in various forms of mulch to protect crops and increase yields has grown significantly. In the publication, the authors attempted to analyze selected commercial properties, but also mulch produced on a laboratory scale, based on biodegradable and petroleum-derived materials.

Performance of Biodegradable Biochar-Added and Bio-Based Plastic Clips for Growing Tomatoes.

Increasing quantities of waste from using conventional plastic in agriculture and horticulture is one of the most pressing issues nowadays. Conventional plastic accessories (e.g., mulching films, clips, pots, strings, etc.) are typically fossil-derived, non-biodegradable and difficult to recycle after their use. Therefore, there is a need for biodegradable and bio-based alternatives with similar properties to conventional plastics, which can be disposed of through degradation in water, soil or compost under specific conditions. This work investigated the properties and the performance of biodegradable biochar-added and bio-based stem and arch support clips. In addition, the investigated clips were composted with tomato residues during 16 week laboratory composting. The scope of this work included: (1) the production of stem and arch support clips in a pilot installation using injection molding technology, (2) an analysis of their chemical composition, biodegradability, disintegration and phytotoxicity, (3) an evaluation of their performance in the greenhouse cultivation of tomatoes and (4) an evaluation of the composting of the clips with on-farm organic waste as an end-of-waste management method. The stem support clips during industrial composting (58 °C) degraded at 100% after 20 weeks, whereas during home composting (30 °C) the degradation was slow, and after 48 weeks the maximum weight loss was 5.43%. Disintegration during industrial composting resulted in 100% fragmentation into particles with sizes less than 2 mm. Phytotoxicity tests demonstrated that the substrates after industrial and home composting did not have a negative effect on the growth of the test plants (i.e., mustard, wheat, cuckooflower). The biochar-added stem support clips proved to be satisfactory alternatives to conventional non-biodegradable, fossil-derived clips and can be disposed of through composting. However, more work is needed to determine the optimal conditions for composting to ensure rapid degradation of the clips in relevant environments.

End-of-Life Management of Biodegradable Plastic Dog Poop Bags through Composting of Green Waste.

Plastic waste derived from plastic dog poop bags (DPBs) could be considered a negligible source of plastic waste. However, it is estimated that this kind of waste contributes to 0.6% of the total plastic waste generated worldwide, and it is expected to increase in the following years. Plastic dog poop bags can be replaced with biodegradable and bio-based alternatives. These alternatives can biodegrade in various environments such as composting, soil, or water and thus allow for end-of-life management without the risk of contaminating the environment with microplastics. However, not all biodegradable bags are always compostable. In this study, we tested composting as the end-of-life management of selected biodegradable dog poop bags (i.e., prototypes of bags and commercially available bags). We analyzed the biodegradation of selected biodegradable plastic dog poop bags during the composting of green waste in laboratory composting reactors after 4 weeks and 90 days of composting. All the investigated DPBs decomposed 100% after 90 days of composting. However, the fresh compost obtained after the 90-day composting of green waste mixed with the investigated bags containing dog poop did not demonstrate high quality.

Influence of Pyrolysis Temperature on the Heavy Metal Sorption Capacity of Biochar from Poultry Manure.

Sorption properties of various biochars have been extensively investigated by many researchers. One of the parameters that have a significant impact on sorption properties is pyrolysis temperature. This paper presents a study on the effect of pyrolysis temperature (425, 575, 725 °C) on the sorption properties of poultry-manure-derived biochar (BPM). The produced biochars, i.e., BPM425, BPM575 and BPM725, demonstrated specific properties at 425, 525 and 752 °C such as high pH (10.40, 10.65 and 12.45), high ash contents (52.07, 61.74 and 78.38%) and relatively low BET (Brunauer, Emmett and Teller) surface area (11, 17 and 19 m2·g-1). The analysis of the mineral phases of the BPMs confirmed the buffering capacity. The investigated biochars were tested for sorption of Zn, Cd and Pb in mono-, double- and triple-metal batch sorption tests. According to the obtained results, biochar produced at a temperature of 575 °C (BPM575) can function as a sufficient sorbent for the removal of Zn, Cd and Pb from a water solution. The presented results do not confirm the effect of competing metal ions on the sorption efficiency of the selected metals by the investigated biochars. Based on that, the studied biochar sorbents can be used in environments contaminated with many metals.

Management of poultry manure in Poland - Current state and future perspectives.

This review aimed to analyse the current state of management practices for poultry manure in Poland and present future perspectives in terms of technologies allowing closing the loops for circular economy, and thus recovery of nutrients and energy. The scope of the review focused primarily on: (1) the analysis of poultry production and generation of poultry manure with special references to quantities, properties (e.g. fertilizing properties), seasonality, etc.; (2) the overview of current practices and methods for managing poultry manure including advantages and limitations; (3) the analysis of potential and realistic threats and risk related to managing poultry manure, and also (4) the analysis of promising technologies for converting poultry manure into added value products and energy. The review addressed the following technologies: composting of poultry manure to obtain fertilizers and soil improvers, anaerobic digestion of poultry manure for energy recovery, and also pyrolysis of poultry manure into different types of biochar that can be applied in agriculture, horticulture and industry. Poultry manure is rich in macro- and micronutrients but also can contain various contaminants such as antibiotics or pesticides, and thus posing a realistic threat to soil and living organisms when applied to soil directly or after biological treatment. The main challenge in poultry manure processing is to assure sufficient closing of carbon, nitrogen and phosphorous loops and safe application to soil.

Nitrification within composting: A review.

Composting could be regarded as a process of processes because it entails a number of complex chemical and microbiological reactions and transformations. Nitrification is one of such processes that normally takes place during the curing phase. This process has been studied in detail for wastewater treatment, and it is becoming an extensively studied topic within composting. In the past, nitrate presence in compost has been clearly perceived as a maturation indicator; however, nowadays, nitrate formation is also conceived as a way of conserving nitrogen in compost. Nitrification is a process closely linked to other processes such as ammonification and the possible loss of ammonia (NH3). Nitrification is defined as conversion of the most reduced form of nitrogen (NH3) to its most oxidized form (i.e. nitrate) and it is performed in two steps which are carried out by two different groups of microorganisms: the ammonia-oxidizing bacteria or archaea (AOB/AOA) and the nitrite-oxidizing bacteria (NOB). The objectives of this review are: a) to gather relevant information on nitrification, which can specifically occur during composting, b) to outline ultimate findings described by the literature in order to increase the understanding and the application of nitrification within composting, and c) to outline future research direction.

Biochar to reduce ammonia emissions in gaseous and liquid phase during composting of poultry manure with wheat straw.

Composting of poultry manure which is high in N and dense in structure can cause several problems including significant N losses in the form of NH3 through volatilization. Biochar due to its recalcitrance and sorption properties can be used in composting as a bulking agent and/or amendment. The addition of a bulking agent to high moisture raw materials can assure optimal moisture content and enough air-filled porosity but not necessarily the C/N ratio. Therefore, amendment of low C/N composting mixtures with biochar at low rates can have a positive effect on composting dynamics. This work aimed at evaluating the effect of selected doses of wood derived biochar amendment (0%, 5% and 10%, wet weight) to poultry manure (P) mixed with wheat straw (S) (in the ratio of 1:0.4 on wet weight) on the total ammonia emissions (including gaseous emissions of ammonia and liquid emissions of ammonium in the collected condensate and leachate) during composting. The process was performed in 165L laboratory scale composting reactors for 42days. The addition of 5% and 10% of biochar reduced gaseous ammonia emission by 30% and 44%, respectively. According to the obtained results, the measure of emission through the condensate would be necessary to assess the impact of the total ammonia emission during the composting process.

Biochar amendment for integrated composting and vermicomposting of sewage sludge - The effect of biochar on the activity of Eisenia fetida and the obtained vermicompost.

Sewage sludge derived biochar (SSDB) was used as a supplementary material for municipal sewage sludge (SS) and wood chips mixtures (WC) treated by combined composting and vermicomposting. SSDB added to the mixture before composting resulted in significantly higher reproduction rate: on week 4 the number of cocoons increased by 213% when compared to the mixture with no biochar. On week 6 the average number of juveniles increased 11-fold in the mixture with biochar added before composting and 5-fold in the mixtures with biochar added after composting when compared to the mixture with no biochar. Biochar added before composting reduced bioavailability of Cd and Zn to E. fetida. The biochar-added vermicomposts showed good fertilizing properties except for elevated concentrations of Cr. The pH of all vermicomposts was in the range of 5.27-5.61. The obtained vermicomposts can be used as a growing medium for horticultural purposes or as an amendment in calcareous soils.

Nitrification during extended co-composting of extreme mixtures of green waste and solid fraction of cattle slurry to obtain growing media.

Next generation of waste management systems should apply product-oriented bioconversion processes that produce composts or biofertilisers of desired quality that can be sold in high priced markets such as horticulture. Natural acidification linked to nitrification can be promoted during composting. If nitrification is enhanced, suitable compost in terms of pH can be obtained for use in horticultural substrates. Green waste compost (GW) represents a potential suitable product for use in growing medium mixtures. However its low N provides very limited slow-release nitrogen fertilization for suitable plant growth; and GW should be composted with a complementary N-rich raw material such as the solid fraction of cattle slurry (SFCS). Therefore, it is important to determine how very different or extreme proportions of the two materials in the mixture can limit or otherwise affect the nitrification process. The objectives of this work were two-fold: (a) To assess the changes in chemical and physicochemical parameters during the prolonged composting of extreme mixtures of green waste (GW) and separated cattle slurry (SFCS) and the feasibility of using the composts as growing media. (b) To check for nitrification during composting in two different extreme mixtures of GW and SFCS and to describe the conditions under which this process can be maintained and its consequences. The physical and physicochemical properties of both composts obtained indicated that they were appropriate for use as ingredients in horticultural substrates. The nitrification process occurred in both mixtures in the medium-late thermophilic stage of the composting process. In particular, its feasibility has been demonstrated in the mixtures with a low N content. Nitrification led to the inversion of each mixture's initial pH.

Co-composting of poultry manure mixtures amended with biochar - The effect of biochar on temperature and C-CO2 emission.

Biochar as an amendment could have an impact on composting dynamics. This study investigated the effect of the addition of biochar (B) to poultry manure (P) mixed with wheat straw (S) (i.e. P:S, P:S+5%B and P:S+10%B) on temperature and carbon dioxide emission. For temperature studies a modified equation for net degree-hour parameter DHnet (°Chday(-1)) was proposed. The modified equation takes into account ambient temperature. The highest daily temperatures DHnet were observed on day 2 and the mixture with the highest addition of biochar (P:S+10%) reached the max temperature. The period of thermophilic temperatures (40°C>) was shorter for mixtures amended with biochar. The addition of biochar increased C-CO2 emission and the total C-CO2 emission were higher about 6.9% and 7.4% for P:S+5%B and P:S+10%B, respectively.

Evolution of process control parameters during extended co-composting of green waste and solid fraction of cattle slurry to obtain growing media.

This study aimed to monitor process parameters when two by-products (green waste - GW, and the solid fraction of cattle slurry - SFCS) were composted to obtain growing media. Using compost in growing medium mixtures involves prolonged composting processes that can last at least half a year. It is therefore crucial to study the parameters that affect compost stability as measured in the field in order to shorten the composting process at composting facilities. Two mixtures were prepared: GW25 (25% GW and 75% SFCS, v/v) and GW75 (75% GW and 25% SFCS, v/v). The different raw mixtures resulted in the production of two different growing media, and the evolution of process management parameters was different. A new parameter has been proposed to deal with attaining the thermophilic temperature range and maintaining it during composting, not only it would be useful to optimize composting processes, but also to assess the hygienization degree.