Biochar from food waste

I have a few Qs here...

• where does food waste best fit in a waste hierarchy? does it have better utility as animal feed or in a localised BSF industry
• what sort of H&MB numbers are going to work at scale, with all that water to remove? is hydrothermal carbonisation a better path for this type of waste stream
• recovering P from our industrial food and sewage systems is important... is biochar production going to become a key player?

Properties of Biochar from Anaerobically Digested Food Waste and Its Potential Use in Phosphorus Recovery and Soil Amendment

Shakib Alghashm ¹, Shiying Qian ¹, Yinfeng Hua ², Jian Wu ², Haitao Zhang ², Weihua Chen ² and Guoqing Shen ^1,*

¹School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China

²Shanghai Liming Resources Reuse Co. Ltd., Shanghai 201209, China

^*Author to whom correspondence should be addressed.

Received: 14 November 2018 / Accepted: 5 December 2018 / Published: 10 December 2018

Abstract

The disposal of a large amount of biogas residue from anaerobically digested food waste is a burden for biogas production. The aim of this work was to investigate biogas residue as a potential feedstock, by preparing biochar at a broad pyrolysis temperature range of 400–900 °C. The properties required for phosphorus recovery and soil amendment application were evaluated. Biogas residue collected from an urban food waste treatment plant was pyrolyzed in a laboratory scale reactor. It was found that by increasing the pyrolysis temperature, the yield of biochar decreased and the pH, electrical conductivity and Brunauer–Emmett–Teller surface area increased. The amount of phosphorus adsorbed onto the biogas residue-derived biochar (BRB) at 900 °C was larger than that of other kinds of biochar. The kinetics of phosphorus (P) adsorption on BRB could be described by the pseudo-second-order equation. The pot experiments showed that the resulting biochar is beneficial for the growth of cabbage. Overall, turning solid residue from the anaerobic digestion of food waste for biogas production into biochar shows good prospects as a means of solving the disposal problem, while creating new markets for food waste biogas residue.

More on Biochar & AD @BiomassMagazine

Biochar could benefit anaerobic digestion of animal manure @BiomassMagazine: New research by Texas A&M AgriLife Research scientists shows biochar has potential to make anaerobic digestion of animal manure a more efficient method to rid farms of waste while producing methane for energy.

see also: https://sea-biochar.blogspot.my/2017/10/ibi-webinar-anaerobic-digestion-and.html

IBI Webinar: Anaerobic Digestion and Biochar

Register Now for the IBI Webinar: Synergies Between Anaerobic Digestion & Biochar October 30, 2017 3:30-5:00 pm EDT

Research has shown that there are many synergies to be found integrating pyrolysis and gasification with anaerobic digestion (AD) systems. Carbonizing the anaerobic digested fibers could be a viable way to create adsorbent for the removal of soluble phosphorous from Anaerobic digesters effluents. Using biochar in the AD substrate can boost not only the quantity but the quality of the methane (CH4) produced. It can also reduce the H2S generated during the AD process thereby reducing wear and tear on equipment. In the webinar we will discuss the possibilities to integrate acidic biochars with dissolved air flotation systems for ammonia removal. The focus of this webinar is on pyrolysis and gasification, two technologies that are capable of converting the digested fibers into a bio-char, and that can be integrated with AD. During the presentation Dr. Garcia-Perez will also discuss some of the potential uses of these chars in anaerobic digestion systems. Cost? Free to IBI Members or $40 for non-members When? Date: October 30, 2017 Time: 3:30 - 5:00 pm EDT To Register: Registration includes access to the slides and a recording of the webinar. IBI Members register here (go to the upcoming webinars section). Your event link will be emailed to you after successful confirmation about your membership status. *** Link will be working soon – we are experiencing some difficulties with updating the IBI website. Non-IBI members register here.

Dr. Manuel Garcia-Perez Washington State University

Dr. Manuel Garcia-Perez is an Adjunct Professor at Washington State University’ Chemical Engineering and BioEngineering Department. His focus is on biomass thermochemical conversion (torrefaction, pyrolysis, gasification and combustion); development and testing of new bio-oil refineries to produce advanced bio-fuels and bio-chemicals; environmental impact of thermochemical processes research addresses the environmental burden associated with the world’s declining petroleum resources.

http://myemail.constantcontact.com/IBI-Webinar-Anerobic-Digestion-and-Biochar.html?soid=1124199130091&aid=fnA1qNYjg_8

Biochar increases biogas production in a batch digester charged with cattle manure (Lao PDR)

Abstract
"Two in vitro incubation experiments were conducted to test the hypothesis that biochar would serve as support media for biofilm development in a biodigester and would as a result increase the yield of biogas whether added separately or enclosed in a nylon bag The treatments in experiment 1 were: control (no biochar), biochar added at 1% of the substrate DM in the biodigester, biochar added at 3% of the substrate DM in the biodigester. The substrate was fresh manure from cattle fed dried cassava root, fresh cassava foliage and urea. Proportions of water and manure were arranged so that the manure provided 5% of the solids in the biodigester. Gas production was measured daily over the fermentation period of 30 days; methane in the gas was measured after 21 and 28 days. In experiment 2, a 2*2 factorial arrangement with 4 replications was used to compare level of biochar: 1% of solids in the digester or none; and presence or absence of a cloth bag in the biodigester. The fermentation was followed over 21 days with daily measurement of gas production and content of methane in the gas at the end of the fermentation.

In experiment 1, incorporation of 1% (DM basis) of biochar in the biodigester increased gas production by 31% after 30 days of continuous fermentation; there were no benefits from increasing the biochar to 3% of the substrate DM. The methane content of the gas increased with the duration of the fermentation (24% higher at 28 compared with 21 days) but was not affected by the presence of biochar in the incubation medium. In experiment 2, adding 1% of biochar (DM basis) to the substrate increased gas production by 35%, reduced methane content of the gas by 8%, increased the DM solubilized (by 2%) and increased methane production per unit substrate solubilized by 25%. Presence of the cloth bag increased gas production when it also contained biochar but decreased it when added to the biodigester without biochar. There was a similar interaction for methane produced per unit substrate solubilized."
http://www.lrrd.org/lrrd24/12/sang24212.htm?goback=.gde_2446475_member_243421682