Roy Posmanik

Agricultural Research Organization (ARO), Neve Yaar, Israel · Institute of Soil, Water and Environmental Science

To address the grand challenge of increasing the sustainability of wastewater treatment plants, hydrothermal carbonization was studied as a nutrient recovery platform, transforming sludge into a valuable hydrochar. Carbonization was achieved at different temperatures (200-300 °C) and durations (30-120 min). The highest mass recovery (73%) was obser...

Accumulation of plastic waste is harming eco-systems and it is time to move towards a circular plastic economy. Sustainable production and recycling processes for plastics are challenged mostly by the lack of renewable building blocks. This study investigates hydrothermal processing (HTP) as a platform for depolymerization of two commonly used plas...

Throughout history, the first and foremost role of urban water management has been the protection of human health and the local aquatic environment. To this end, the practice of (waste-)water treatment has maintained a central focus on the removal of pollutants through dissipative pathways. Approaches like – in the case of wastewater treatment – th...

Global population growth is creating severe pressure on wastewater treatment plants, and specifically on sludge management. Meanwhile, the global challenge of achieving food-security requires the development of green pest control practices that maximize crop productivity. The hydrothermal technology, using subcritical water as the conversion media...

Hydrothermal carbonization (HTC) of raw and anaerobically digested (AD) manure with either water or whey was studied, with the goal of recovering energy and nutrients. Specifically, the impacts of HTC reaction temperature (180–240 °C), solid feedstock, and type of liquid on hydrochar quality and aqueous phase properties were tested. Of the hydrocha...

Sewage sludge management is a major operational task that challenges sustainability in municipal wastewater treatment plants. On the other hand, the high level of organic carbon in sewage sludge suggests its utilization potential for renewable energy applications. This study investigates hydrothermal carbonization (HTC) of anaerobic sludge at incre...

Recovery of nutrients, such as ammonia, from wastewater offers an attractive approach to increase the overall sustainability of waste management practices. Conventional wastewater treatment processes require significant energy input, and the useful form of nitrogen (ammonia), is usually lost. Ammonia, a major component of fertilizers, is convetiona...

The biochemical methane potential (BMP) assay is a standard method for characterizing biomethane potential and anaerobic biodegradability organic waste streams. Therefore, the BMP protocol must be standardized to reliably compare these parameters for various substrates. Here, the effect of inoculum selection on biomethane potential was investigated...

Manure conversion into energy products via hydrothermal liquefaction was studied. Hydrothermal reactions, conducted at different temperatures (200–300°C), were compared on the basis of conversion yields, carbon and energy recoveries and products' quality. The results demonstrate how reaction temperatures affect the relative production of biocrude o...

There is increasing global interest and policies being enacted to lower greenhouse gas emissions, especially from the agricultural sector. In the U.S. for example, states with large dairy operations may combine proven manure valorization technologies, such as anaerobic digestion and hydrothermal liquefaction. Sustainable manure treatment would incr...

Anaerobic digestion coupled with combined heat and power production on dairy farms is environmentally advantageous; however, high capital and operating costs have limited its adoption, especially in the United States, where renewable electricity and heat production are under-incentivized. Biogas is also at a disadvantage because it has to compete w...

Increased demand for water, energy and food requires new ways to produce fertilizers, fuels and reusable water. Recovery of resources from wastes could lead to an additional source of energy and nutrients, and also reduce the waste to be disposed. In this work, we used hydrothermal liquefaction to produce a biocrude oil product, followed by membran...

Anaerobic digestion systems on dairy farms in New York State rely on gate-fee revenues from co-digestion to ensure economic viability. Yet, because gate fees are paid on a volumetric (or weight) basis, farmers have been compelled to accept large waste volumes. When these wastes are co-digested at rates exceeding the design capacity of the digester,...

The objective of this study was to elucidate the effect of adding acid and alkali to hydrothermal liquefaction (HTL) of two waste biomass feedstocks—manure digestate and carbohydrate-rich food waste. HTL reactions were conducted at 300 °C for 60 min, with and without the addition of acid or base. We measured the quantity and characterized the quali...

Anaerobic digestion (AD) is a mature biotechnology-production platform with millions of installations at homes, farms, and industrial/municipal settings. Large-scale industrial, agricultural, and municipal waste-treatment systems may observe novel integration with electrochemical, biological, physical, and thermochemical process units to make AD mo...

This study characterized the hydro-char by-product from hydrothermal liquefaction (HTL) of waste feedstocks at two operating temperatures (250 and 300 ○C) and times (5 and 60 minutes). The feedstocks were a selection of wastes from: dairy industries (manure and yogurt whey), municipal wastewater treatment plant, dining halls, fruit and alcohol manu...

Expansion of dryland agriculture requires intensive supplement of organic fertilizers to improve the fertility of nutrient-poor desert soils. The environmental impact of organic supplements in hot desert climates is not well understood. We report on seasonal emissions of nitrous oxide (N2O) from sand and loess soils, amended with limed and non-lime...

Hydrothermal liquefaction converts food waste into oil and a carbon-rich hydrothermal aqueous phase. The hydrothermal aqueous phase may be converted to biomethane via anaerobic digestion. Here, the feasibility of coupling hydrothermal liquefaction and anaerobic digestion for the conversion of food waste into energy products was examined. A mixture...

Thermochemical and biological processes represent promising technologies for converting wet biomasses, such as animal manure, organic waste, or algae, to energy. To convert biomass to energy and bio-chemicals in an economical manner, internal energy recovery should be maximized to reduce the use of external heat and power. In this study, two conver...

The hydrothermal conversions of three model compounds—starch, bovine serum albumin and linoleic acid—and their binary and ternary mixtures were evaluated. Batch experiments were operated at 250–350 °C, 5–20 MPa for 10–60 minutes. Bio-oil produced from sugars, proteins and their mixtures contained ∼70% carbon and ∼15% oxygen (w/w) with higher heatin...

Ammonia emissions from poultry-manure disposal and agricultural applications pose a global environ-mental challenge that requires the development of proper management practices. Recently, a schemecomprised of a compost-based biofilter for the treatment of high loads of ammonia emitted from poultry-manure digestion (up to 500 g NH3m−3biofilter day−1...

Commonly used management practices of manure involve anaerobic digestion followed by land application of the digested manure. Lime treatment has been suggested as a further disinfection step, to eliminate residual pathogens. Recently, we suggested a combined treatment in which ammonia (NH3) from manure digestion is diverted into a compost nitrifyin...

A novel system for organic waste stabilization and reuse, combined with production of nitrate-rich liquid fertilizer was developed by manure digestion followed by volatilization of ammonia-rich gas (originating in manure extract) and its nitrification and recovery. This approach has several advantages, including biowaste stabilization and high reco...

The effect of fertigation with half-strength Hoagland-based media with different N sources on the appearance of lettuce plants after 40 days of irrigation. The average N concentration used was 60 mg L−1. The N sources were: a KNO3, b N-free, c end product of the new device (LOFPS), d guano extract

Release of gaseous ammonia from guano extract as continuously measured by gaseous ammonia-specific electrode: a with addition of Ca(OH)2 to raise the pH on day 11, b without addition of Ca

A major input in intensive organic agriculture is nutrient-rich liquid fertilizers. Guano and other fowl manure are frequently digested in water extracts, and the supernatant is supplied as fertilizer. The resultant manure biowaste (MBW) is commonly disposed of to the environment, posing potential pollution and health risks. The study aims were to...

Agro bio-waste such as fowl manure creates a global environmental challenge and the development of proper management schemes, allowing its safe disposal, is of importance. The concept of the LOFPS (liquid organic fertilizer production system), was suggested, based on laboratory scale studies, as N-rich bio-waste management scheme which combines its...