Page 54 - demo

CURRENT STATUS OF TECHNOLOGY AND TRENDS

specific scheme suitable to the feed characteristics. There are however several reports of
demonstration plants for some of these feedstocks individually or co-processed with different
renewable feedstocks, and also sometimes with coal. Technologies for feed preparation
for incineration or power generation from all these types of biomass are available. The key
requirement is to make necessary adjustments to suit the gasification reactor for syngas
production.
Biogas from anaerobic digesters, refinery, steel or cement plant off gases, is often processed
along with other feedstocks, depending upon their composition. Sometimes specific
pretreatment or mixing ratio adjustments are required before feeding into the reactor [15 & 44].
As such there is not much challenge in the availability of these technologies, but for each case
a specific scheme has to be derived.
Dry reforming of methane with carbon dioxide is another route to produce syngas, although this
is especially suited for hydrogen production via shift reaction. The feed preparation requirement
for natural gas is only the removal of sulfur by hydro-treating and passing through Zinc Oxide
for complete sulfur removal. When higher hydrocarbons such as naphtha are used, a pre
reforming section is necessary and technology for this is available from many licensors [46].

3.8 Production of Syngas

Steam reforming of natural gas is a well-established route to make syngas and hydrogen.
Methane reforming reactors operate at above 800 C and at 1.5 – 3 MPa pressure. Typically
0
the hot methane and steam is passed through tubes filled with Nickel Oxide catalyst on support.
Several companies such as Haldor Topsøe, BASF, United Catalysts and ICI are suppliers of
these catalysts.
Technologies for partial oxidation and gasification of natural gas, and solid or liquid hydrocarbon
sources based on fossil fuels, are well established. Technology variations are in the gasifier
design, operating temperature, pressure, energy management system, oxygen separation,
carbon capture etc. Most of the commercial plants operate without any catalyst, and the
technologies are matured and can be easily sourced from many available options.

Complete technology stacks covering gasification, syngas production and shift reaction for gas
or coal based units for large scale IGCC plants are available from Lurgi, GE, Conoco Phillips,
Shell and a few other companies. There are several players who are developing new types of
gasifiers and other related processes. Many of them have been operating demonstration plants
or even small and medium size plants for commercial production of syngas. The most active
players in developing new gasifier designs are Kellogg Brown & Root (KBR), Future Energy,
Mitsubishi Heavy Industries (MHI), British Gas/Lurgi (BGL) etc. [48].
Production of syngas from biomass is receiving good attention in recent times. There are many
medium sized biomass based combustors and gasifiers operating today. There are several
power generation units based on renewable feedstocks producing syngas for burning. India
also has many small and medium size combustion units operating today. However, there are
very few operating plants in the world processing biomass for DME/Methanol manufacture:
Broomfield, CO – Range Fuels Inc. in Soperton Georgia, Haldor Topsøe’ technology in
Chemrec from paper mill waste in Sweden, Enerkem’s woody mass to methanol at Edmorton,
Alberta [33,36,39 &40] etc.

The most important part of syngas purification is tar removal. This is particularly necessary
for low grade carbon sources both from fossil and renewable origin. For both gas turbines
as well as for chemical synthesis this is very important. Envitech offers technologies for gas
cleaning systems [49]. Since special attention is required for syngas cleaning when using a
low grade source, which is the preferred feed stock, several organizations are working in this

54 Methanol and DME Production: Survey and Roadmap | 2017