Demand for coal is increasing with the world’s growing appetite for energy. However, depletion of the highest-quality deposits and stricter emissions legislation mean that operators need to use lower-quality coal in more environmentally acceptable ways.
The Shell Coal Gasification Process (SCGP) is a mature, efficient and reliable technology. It converts a wide range of coal to syngas that can be used:
- To generate power through the integrated gasification combined cycle (IGCC) with lower emissions than from burning coal or even natural gas, and a concentrated carbon dioxide stream for optional CCS;
- As an alternative feedstock for chemical manufacture;
- To produce high-value synthetic liquid fuels and lubricants; and
- To produce hydrogen via water–gas shift.
Our coal gasification technology is available in two line-ups designed to meet different user business objectives:
- The SCGP syngas cooler line-up offers high thermal efficiency and is especially suitable for large projects and IGCC power generation.
- The bottom water-quench line-up uses the same mature reactor membrane wall/burner technology but with a simplified syngas cooler configuration that reduces capital costs by up to 30% and increases feedstock flexibility.
We can support your project throughout the project lifecycle. Ask us about our business, operational-support and project-execution services, including:
- Design and engineering;
- Commissioning and start-up;
- Experience transfer;
- Master planning; and
Reliable and scalable. An inert carrier gas transports dry, pulverised coal into the gasifier, where it contacts oxygen and steam. Our gasifiers use a membrane wall of high-pressure water/steam tubes and multiple burners to separate the syngas from the slag. The slag flows down into a water bath, from where it can be extracted as a solid. Multiple burners provide the potential for easy scale-up.
In the SCGP syngas cooler line-up, recycled syngas is used to quench the syngas exiting the reactor, which is then cooled further in an external cooler to generate high- and medium-pressure steam as valuable by-products.
In the bottom water-quench line-up, the syngas is cooled directly in a proven water-quench system.
Why select SCGP technology?
- It is unique and proven. SCGP units use special membrane wall and multiple burner designs. Nearly 40 years [Link to timeline] has passed since our first pilot coal gasifier started. There are now more than 30 SCGP reactors operating [Link to map] or in the planning stages across the world. Over 100 coal types have been successfully processed, including blends of high-ash coal and petcoke.
- It works. SCGP technology can process a wide range of coals, from lignite to anthracite, and including petcoke and biomass blends. It also offers:
- Low coal consumption (510–615 kg per 1,000 Nm3 of effective syngas);
- Low oxygen consumption (310–350 Nm3 oxygen per 1,000 Nm3 of effective syngas);
- Low freshwater consumption; and
- High throughput and availability, and low maintenance costs by using proven reactor membrane wall and burner technology.
- The SCGP syngas cooler line-up:
- Has a higher thermal efficiency;
- Produces less waste water; and
- Generates high- and medium-pressure steam, which can help to reduce operating expenditure.
- Our bottom water-quench line-up:
- Requires up to 30% less capital expenditure and offers more stable operation through its simplified configuration; and
- Widens coal suitability by eliminating the fouling risk in the syngas cooler.
- It can reduce capital and operational costs. The multiple-burner design is easily scaled up to give larger units and is highly reliable, which removes the need to build a spare gasifier. This means fewer operatives, less maintenance and a smaller spare parts inventory are necessary. Units with a dry coal intake capacity of 3,200 t/d have already been designed.
- It keeps getting better. As an owner and operator, and through close partnerships with other users, Shell has the insight and experience to deliver. We record innovations and improvements in a lessons-learned database for the benefit of all licensees and to improve our master design. Focusing on continuous improvement through innovation and partnership helps us to achieve longer continuous runs and lower maintenance costs.
- It is supported. Our global SCGP technical service centre provides dedicated life-cycle support for lifetime assurance, including design, simulation, start-up assistance and training, and long-term operational assistance. Lessons learned are shared through regular user conferences. We facilitate global technology-user conferences that aim to build user communities and accelerate learning. Ask us about arranging a site visit.