Yao Zhiyi

Yao Zhiyi  

Personal Particulars
Research Fellow
Department of Chemical & Biomolecular Engineering,

National University of Singapore, 4 Engineering Drive 4,

Singapore, 117576

Office: E1A-04-01
Phone: (65) 9084 1445
Email: cheyaoz@nus.edu.sg

Education

Ph.D, Chemical & Biomolecular Engineering, National University of Singapore, Singapore, 2013-2018.

B.Eng., Mechanical Engineering, Shanghai Jiao Tong University, China, 2009-2013.

Research Interests

Numerical simulation and experimental study on fixed-bed downdraft gasifier;

Anaerobic digestion and gasification hybrid system for potential energy recovery from yard waste and woody biomass;

Monitoring and characterization of particulate emission from the gasification and pyrolysis of biomass;

Reutilization of carbon black waste.

Spin-off Company of NUS: https://www.cbeecosolutions.com/

Research highlights

Ø  Numerical simulation and experimental study on fixed-bed downdraft gasifier for syngas and biochar co-production
·         The gasification model has the capacity to predict the production rate and quality of both syngas and biochar.

·         Economic evaluation was conducted taking into account economic value of produced syngas and biochar.

·         A three-region approach was applied to simulate heat and mass transfer inside the reactor based on different gas velocity profiles.

·         Several factors were investigated for evaluation of gasification performance, including the moisture content of feed stock, equivalence ratio, and air inlet location.

 

Ø  Anaerobic digestion and gasification hybrid system for potential energy recovery from yard waste and woody biomass
·         The feasibility of the proposed two-stage hybrid system was validated experimentally and numerically.

·         The proposed hybrid system could effectively improve the quality of produced gas.

·         The operating parameters were optimized to improve the overall energy efficiency of the system.

·         Drying process was found to play an important role in determining overall energy efficiency.

·         Optimal moisture content of AD residue was investigated for maximizing energy efficiency.

 

Ø  Particulate Emission from the Gasification and Pyrolysis of biomass: Concentration, Size Distributions, Respiratory Deposition-based Control Measure Evaluation

·         PM emissions of gasification and pyrolysis are compared.

·         The particles emitted from gasification and pyrolysis are mainly PM0.25-1.0 and PM1.0-2.5

·         Particle respiratory deposition modelling shows that most particles penetrate deeply into the last stage of the human respiratory system

·         A particle respiratory deposition-based cyclone design scheme is proposed.

·         The cyclone vortex finder diameter is the most sensitive design parameter.

 

Patent:

 Wang CH (30%*), Babu CM (30%*), Yao Z(30%*),  Anbu MT (10%*). A Cost-effective Way of Converting Low-grade Carbon to Activated Carbon for Environmental Applications. SG Non-Provisional Application No. 10202003008X (* contribution percentage)

Journal publications:

1. Yao Z, He X, Hu Q, Cheng W, Yang H, & Wang CH. A Hybrid Peripheral Fragmentation and Shrinking-core Model for Fixed-bed Biomass Gasification. Chemical Engineering Journal, 2020: 124940.

2. Yao Z, You S, Dai Y, Wang CH. Particulate emission from the gasification and pyrolysis of biomass: Concentration, size distributions, respiratory deposition-based control measure evaluation. Environmental pollution. 2018 Nov 1;242:1108-18.

3. Yao Z, You S, Ge T, Wang CH. Biomass gasification for syngas and biochar co-production: Energy application and economic evaluation. Applied Energy. 2018 Jan 1;209:43-55.

4. Yao Z, Li W, Kan X, Dai Y, Tong YW, Wang CH. Anaerobic digestion and gasification hybrid system for potential energy recovery from yard waste and woody biomass. Energy. 2017 Apr 1;124:133-45.

5. You S, Yao Z, Dai Y, Wang CH. A comparison of PM exposure related to emission hotspots in a hot and humid urban environment: Concentrations, compositions, respiratory deposition, and potential health risks. Science of the Total Environment. 2017 Dec 1;599:464-73. († Authors contribute equally to this work.)

6. Zhan G, Yao Z, Ng WC, Li H, Lim MX, Zhi Y, Koh SN, Wang CH. Economic Production of Monoclinic Bismuth Vanadate from Waste Vanadium Ions: Process Design and Cost-Benefit Analysis. Journal of Cleaner Production. 2019 Dec 10;240:118188. († Authors contribute equally to this work.)

7. Li L, Yao Z, You S, Wang CH, Chong C, Wang X. Optimal design of negative emission hybrid renewable energy systems with biochar production. Applied Energy. 2019 Jun 1;243:233-49.

8. Tong H, Yao Z, Lim JW, Mao L, Zhang J, Ge TS, Peng YH, Wang CH, Tong YW. Harvest green energy through energy recovery from waste: A technology review and an assessment of Singapore. Renewable and Sustainable Energy Reviews. 2018 Dec 1;98:163-78.

9. Ramachandran S, Yao Z, You S, Massier T, Stimming U, Wang CH. Life cycle assessment of a sewage sludge and woody biomass co-gasification system. Energy. 2017 Oct 15;137:369-76.

10. Kan X, Yao Z, Zhang J, Tong YW, Yang W, Dai Y, Wang CH. Energy performance of an integrated bio-and-thermal hybrid system for lignocellulosic biomass waste treatment. Bioresource technology. 2017 Mar 1;228:77-88.

11. Shen Y, Li X, Yao Z, Cui X, Wang CH. CO2 gasification of woody biomass: Experimental study from a lab-scale reactor to a small-scale autothermal gasifier. Energy. 2019 Mar 1;170:497-506.

12. Cui X, Li H, Yao Z, Shen Y, He Z, Yang X, Ng HY, Wang CH. Removal of nitrate and phosphate by chitosan composited beads derived from crude oil refinery waste: Sorption and cost-benefit analysis. Journal of Cleaner Production. 2019 Jan 10;207:846-56.

13. Ong Z, Cheng Y, Maneerung T, Yao Z, Tong YW, Wang CH, Dai Y. Co‐gasification of woody biomass and sewage sludge in a fixed‐bed downdraft gasifier. AIChE Journal. 2015 Aug;61(8):2508-21.

Conference Publications/ Presentations:

1. Yao, Z., Prabhakar AK., Babu CM., Wang C. H.. Treatment and Utilization of Solid Residues from Waste Combustion Facilities and Carbon Black Waste for a Sustainable Environment. PRES’19, 20 – 23 October, Agios Nikolaos, Crete, Greece.

2. Yao, Z., Uzi, A., Ge T.S., Wang C. H.. Multi-Scale Modelling of Biomass Gasification: The Effects of Intraparticle Transfer on Syngas and Biochar Production. AIChE Annual Meeting, Pittsburgh, Pennsylvania, USA, 28 October-02 November 2018.

3. Yao, Z., Li, H., Koh, S. N., Wang C. H.. Experimental Investigation and Process Design for the Conversion of Carbon Black Waste into Valuable Resources. AIChE Annual Meeting, Pittsburgh, Pennsylvania, USA, 28 October-02 November 2018.

4. Yao, Z., You, S., Yan W.C., Dai Y., Tong, Y. W., Wang C. H.. Biomass gasification in a fixed bed downdraft gasifier: experimental study & comprehensive reactor and particle modelling. AIChE Annual Meeting, San Francisco, California, USA, 13-18 November 2016.

5. Yao, Z., Li, W., Kan, X., Dai, Y., Tong, Y. W., Wang, C. H.. Experimental and numerical study on combining anaerobic digestion and gasification for potential energy recovery from biomass and sewage sludge. AIChE Annual Meeting, San Francisco, California, USA, 13-18 November 2016.

6. Yao, Z., Li, W., Kan, X., Dai, Y., Tong, Y. W., and Wang, C. H.. Experimental and numerical study on combining anaerobic digestion and gasification for potential energy recovery from biomass and sewage sludge. 15th International Conference on Sustainable Energy Technologies (SET2016), Singapore, 20-22 July 2016.

7. Kan, X., Yao, Z., Zhang, J., Tong Y. W., and Wang, C. H.. Energy performance of a two-stage treatment for waste lignocellulosic biomass: Effects of organic loading rate, hydraulic residence time and carrier gas. 15th International Conference on Sustainable Energy Technologies (SET2016), Singapore, 20-22 July 2016.