Low Grade Waste-to-Energy Conversion for Electricity, Water Desalination and Cooling using Gasification, MOF Adsorption and Reverse Osmosis in the Kingdom of Saudi Arabia

Summary

This is a joint project between the Department of Chemical Engineering at King Khalid University (KKU), Saudi Arabia, and the School of Engineering at University of Birmingham (UoB). The aim is to develop a waste-to-energy system that can accept a variety of feedstocks (ranging from municipal solid waste [MSW] to agricultural and forestry residues) to provide electricity, space cooling and water desalination.

The desalination processes will yield freshwater for drinking and high-purity water for high-tech industries. Unlike existing cooling and desalination, the system will not rely on fossil fuels. The novel technologies to be employed include adsorption cooling and desalination using Metal Organic Frameworks, and batch-reverse osmosis giving 80% recovery and specific energy consumption below 1 kWh/m3 with brackish water feed. Catalytic gasification will give reliable and clean processing of the mixed feedstocks, producing hydrogen-enriched syngas with steam reforming and then fuelling a combined heat and power engine to drive the desalination and cooling processes.

If uncontaminated biomass waste (e.g. date palm and livestock waste) is used as feedstock in the gasifier then an organic biochar (ash) by-product is also produced which is used for soil improvement by enriching the soil with organic carbon matter. This process will reduce the volume waste by >95% thus also tackling pollution and waste management issues in parallel. Total energy utilisation efficiency from waste gasification is predicted >70%.

Thus, concept will decouple the energy production, water desalination and cooling from reliance on conventional fossil fuels and thus will be ideal for rural and coastal remote locations with waste availability. A pilot plant will be constructed giving >100 m3/day water output from 10 kg/h of waste feedstock. The scientific findings will enable the plant to be constructed at a range of scales for decentralised applications close to the source of the waste feedstocks.

Project Objectives

  1. Develop a flexible and scalable waste to energy gasification process, achieving >70% conversion of energy into useful heat and electricity
  2. Develop an efficient adsorption cooling-desalination system based on MOFs, with coefficient of performance of >0.5, and yielding high-purity water with less than 1 ppm total dissolved solids
  3. Develop a high efficiency, high recovery desalination unit for brackish water based on batch-RO, with recovery 80% and specific energy consumption < 1 kWh/m3, proving scalability to outputs over 100 m3/day.
  4. Integrate the above into a pilot system to demonstrate its feasibility for use in KSA.

Publications

  1. I. Albaik, R. Al-Dadah, S. Mahmoud, M.K. Almesfer, M.A. Ismail, E. Elsayed, M. Saleh, A comparison between the packed and coated finned tube for adsorption system using aluminium fumarate: Numerical study, Therm. Sci. Eng. Prog. 22 (2021) 100859.
  2. I. Albaik, R. Al-Dadah, S. Mahmoud, M. Ismail, M. Almesfer. Coated, packed and combined wire finned tube adsorption cooling and desalination system using metal-organic framework: Numerical study. Energy 2022;247:123506. 
  3. K. Park, I. Albaik, P. A. Davies, R. Al-Dadah, S. Mahmoud, M. A. Ismail and M. K. Almesfer, Batch reverse osmosis (BRO)-adsorption desalination (AD) hybrid system for multipurpose desalination and minimal liquid discharge, Desalination, 2022