Influences of feedstock sources and pyrolysis temperature on the properties of biochar and functionality as adsorbents: A meta-analysis.

A review of China’s municipal solid waste (MSW) and comparison with international regions: Management and technologies in treatment and resource utilization

A critical review on biochar for enhancing biogas production from anaerobic digestion of food waste and sludge

Towards transparent valorization of food surplus, waste and loss: Clarifying definitions, food waste hierarchy, and role in the circular economy.

Review on biomass feedstocks, pyrolysis mechanism and physicochemical properties of biochar: State-of-the-art framework to speed up vision of circular bioeconomy

Waste generated from anthropogenic activities contributes toward stresses on our natural systems through impacts associated with both production and disposal. Sustainable waste management necessitates that industries shift from the current linear model to a circular based economy, utilizing wastes as raw materials for the production of new products, eg. fuels and chemicals. Biomass and associated waste materials can be converted into value-added products using thermochemical processes. The pyrolysis process is a convenient thermochemical method, whereby biomass is efficiently converted into biofuels, biochars and BBQ briquettes; and further processing yields additional value added products, such as activated carbons, carbon black and printing ink. This paper reviews current development work and evaluates potential opportunities for food waste pyrolysis focusing on the conversion of food waste to biochar products. Overall, it was found that the constituents of the food waste together with the process conditions play a major role in the yield and composition of the produced chars. Moreover, more research work needs to be conducted on food waste to biochar and on mixed food blends in particular.

Food waste to biochars through pyrolysis: A review

The future of the global environment is at threat due to global warming and climate change primarily driven by greenhouse gas emissions. Bioenergy with carbon dioxide capture and storage/utilisation (BECCS/U) through its CO2 negative emission capacity is considered a principal component of global mitigation strategies as agreed in the Paris climate change agreement. In this study, the current global status and efforts to implement BECCS systems are comprehensively reviewed. The potential for thermochemical conversion processes (combustion, gasification, pyrolysis, and liquefaction) to manifest within BECCS systems is analysed, in addition to their integration potential with carbon dioxide capture methods. Outcomes suggest that gasification and combustion processes when integrated with CO2 capture and storage (CCS), within combine heat and power (CHP) configurations, biomass integrated gasification combine cycle (BIGCC) and chemical looping cycle (CLC) are mature technologies. Furthermore, this review indicates that pyrolysis and liquefaction process are commercial and lab-scale respectively. When integrated within BECCS systems, pyrolysis systems are at the pilot level and liquefaction processes are at lab scale. Moreover, a comprehensive discussion on the negative emission potential from various BECCS configurations is provided, highlighting their role in advancing bio-refineries through waste management and conversion to value-added products such as biochar, ethanol, bio diesel etc. The pyrolysis process has CO2 mitigation potential of 2.2 GtCO2/year by 2020-2050. Finally, an insight into the commercial barriers and future perspectives of BECCS technologies, role of international supply chains therein, and the need for effective stakeholder management to facilitate BECCS systems within global trade.

A comprehensive review of biomass based thermochemical conversion technologies integrated with CO2 capture and utilisation within BECCS networks

One-third of the edible parts of food produced for human consumption is lost or wasted globally, amounting to 1.3 billion tonnes per year. Food waste contains many constituents, which makes it a promising source for fuels and chemicals production. Moreover, the State of Qatar, which is situated in a hyper arid region is characterized by a disproportionate distribution of resources. It is rich in natural energy resources, but suffers from water scarcity and its natural environment does not encourage food production. Qatar’s economy continues to expand rapidly and faces a number of environmental challenges which include the management and disposal of wastes that are generated by industrial and domestic activities. As such, the pyrolysis of biomass waste and food waste specifically is a viable option to transform waste, which would have otherwise been disposed into the natural environment, into value-added products which can be utilized to enhance resource efficiency, especially water. In this work, the pyrolysis of different food waste has been simulated using Aspen Plus software to produce value-added biochar products. The pyrolysis of food waste in steady-state mode has been studied using a yield reactor, in the 300–600 °C temperature range, by feeding five types of food waste with different ultimate and proximate properties. In addition, the optimum feedstock is identified in which the objective is to optimize food waste blends for maximizing solids to syngas ratio. The optimization results indicated an increase in the yield of the solid biochar product from 36.56% to 41.81%, while both the ash and carbon content decreased slightly. These findings open the doors to the transformation of food waste into value-added biochar via pyrolysis. Furthermore, the produced chars can be utilized in carbon sequestration when applied as soil amendment and as precursors for higher value-added products such as adsorbents.

Simulation of Food Waste Pyrolysis for the Production of Biochar: A Qatar Case Study

As effects of climate change and resource scarcity disturb the modern world, there is an urgent need to shift from the traditional fossil fuel-based economy towards a more sustainable future. Transitioning towards a bio-economy can serve waste reduction and energy diversification objectives. Whilst technologies continue to develop that are capable of processing a wide array of wastes as feedstock, it is necessary to devise methodologies that optimise strategic decisions within bio-economies and increase the competitiveness with traditional fossil fuel-based industries. As such, the objective of this study is to develop an integrated framework that can inform optimal technological pathways for the conversion of various biomass waste into value-added products. The biomass feedstock include: date seeds, municipal solid waste, food waste, camel manure, and sludge. To achieve this objective, a two stage optimisation framework is developed based on three technologies; gasification, pyrolysis, hydrothermal liquefaction. Outputs of process specific models are used in a multi-objective mathematical formulation model to identify optimal pathways that encompass technology pathways and corresponding value-added product for each waste type. The mathematical model maximises the total revenue and minimises total emissions within the waste to value added product pathways. The simulation results demonstrate that the process yield of syngas production using gasification is higher than the pyrolysis for the date seeds, MSW, food wastes, and camel manure by about 58.67%, 69.81%, 60.38%, and 58.32% respectively. The results of the optimisation indicate the need to improve the efficiency of the hydrothermal liquefaction process, which is the optimal pathway to produce bio-oil from date seeds alone. However, for the other waste types, the gasification process is the preferred technology discarding bio-oil quality.

Optimising Multi Biomass Feedstock Utilisation Considering a Multi Technology Approach

The continuing increase in population means an increasing demand for products and services, resulting in huge amounts of waste being discharged into the environment. Therefore, waste management requires the application of new and innovative solutions. One new approach involves converting waste into value-added chemicals and products for use directly or after further processing into higher value-added products. These processes include biological, thermochemical, and physiochemical methods. Furthermore, biosolids, including treated sewage sludge (SS), represent one of the major by-products of human activities, constituting a major environmental hazard and requiring the treatment of contaminated wastewater with associated health hazards. Sustainable solutions to manage and dispose of this type of waste are required. In this review, pyrolysis, a thermochemical conversion technology, is explored to convert biosolids to biochars. The review addresses previous studies, by providing a critical discussion on the present status of biosolids processing, the potential for energy recovery from the pyrolysis bio-oil and biogas, and finally some benefits of the production of biochars from biosolids.

/pdf/pyrolysis-of-biosolids-to-produce-biochars-a-review-17m5ysui.pdf

Samar Elkhalifa

Papers

Food waste to biochars through pyrolysis: A review

A comprehensive review of biomass based thermochemical conversion technologies integrated with CO2 capture and utilisation within BECCS networks

Simulation of Food Waste Pyrolysis for the Production of Biochar: A Qatar Case Study

Optimising Multi Biomass Feedstock Utilisation Considering a Multi Technology Approach

Pyrolysis of Biosolids to Produce Biochars: A Review