News and Trends

The Portland City Council has approved the development of a facility at the Columbia Boulevard Wastewater Treatment Plant that will convert biogas into compressed natural gas vehicle fuel. The facility, which is expected to be operational by 2017, would allow the plant to re-use nearly all of the 600 million cubic feet of biogas it produces annually.

An Environmental Services study of re-use alternatives found that the vehicle fuel option is the most economical and has the greatest environmental benefit as it will reduce diesel fuel use and cut greenhouse gas emissions. Environmental Services is also thinking of several possible uses for fuel, including selling it to a utility company as well as fueling city vehicles.

"Biogas is a sustainable, renewable energy source," said Portland City Commissioner Nick Fish. "This project will reduce our reliance on fossil fuels, reduce greenhouse gas emissions and save money for our sewer ratepayers."

Scania together with Swedfund, the development financier of the Swedish state, are forming a partnership to develop the production of biogas as an vehicle fuel in Nagpur in India. The biogas will be produced from digested sludge from one of the city's wastewater treatment plants.

"This is a Swedish venture, which in a sustainable and profitable manner can create many new jobs and contribute to India's shift towards renewable fuels. Biogas is the fuel of the future, which will contribute to solving India's huge pollution problems while taking a comprehensive approach to the major environmental challenges," says Swedfund's CEO Anna Ryott.

Research and Development

A new study of the University of East Anglia (UEA) specifies five strains of yeast capable of turning agricultural by-products, such as straw, sawdust, and corncobs, into bioethanol. Approximately more than 400 billion liters of bioethanol could be produced each year from crop by-products.

Breaking down agricultural waste has been difficult because many yeast strains necessary for fermentation are inhibited by compounds in the straw. Their toxic effects lead to reduced ethanol production. The team investigated more than 70 strains of yeast to find the most tolerant to furfural. They found five strains that showed resistance and produced the highest ethanol yield.

Of the five strains, Saccharomyces cerevisiae NCYC 3451 showed the greatest resistance. The strain is linked to the yeast used in Japanese rice wine Sake production.

"These strains represent good candidates for further research, development and use in bioethanol production," said Lead Researcher Dr. Tom Clarke of UEA's School of Biological Sciences.

Propane is a hydrocarbon used in a wide range of applications and is a target in research for developing new renewable fuels. Patrik R. Jones and Nigel S. Scrutton from University of Turku in Finland and University of Manchester in UK, respectively, constructed and evaluated alternative microbial pathways for propane production. The new pathways were derived from butanol pathways.

Four different synthetic pathways for the production of propane and butanol were assembled and evaluated. The highest butanol titres were achieved with the atoB-adhE2 and atoB-TPC7 routes. When aldehyde deformylating oxygenase (ADO) was co-expressed with these 2 pathways, they also produced propane. The atoB-TPC7-ADO pathway was the most effective in producing propane.

This study expands the metabolic toolbox for renewable propane production and provides insight and understanding on the development of next-generation biofuel pathways.

In Washington, scientists have refined a strategy known as consolidated bioprocessing (CPB) to reduce costs of producing ethanol from plant biomass. Now, scientists try to engineer a strain of a CBP bacterium called Caldicellulosiruptor bescii that can break down biomass without pretreatment and produce ethanol as well.

Caldicellulosiruptor bescii has been shown to ferment untreated switchgrass, but it lacked the genes to make ethanol. Researchers identified a gene in Clostridium thermocellum and cloned it into C. bescii. The engineered strain of C. bescii was then able to produce ethanol from cellobiose, Avicel, and switchgrass. 

This study is an important step in realizing the potential of CBP and provides a platform for engineering the production of advanced biofuels and other bioproducts directly from cellulosic biomass.

Water-borne algal blooms from farm fertilizer runoff can destroy aquatic life and clog rivers. However, scientists are now working on a way to clean up these algal blooms and turn them into feedstock for biofuels through a nutrient bio-remediation system.

Currently, the research team is exploring different substrates to optimize algae growth in water bodies. They are testing these first in the laboratory before analyzing them out in the field. They are also investigating different options for collection techniques.

John B. Miller, a research lead for the study, points out that the algae can be used for biofuel feedstock, making a profit for the farmers. Meanwhile, the waste left over after the biofuel's fermentation and distillation steps is high in nutrients and carbohydrates, which can be recycled back to farm fields as organic fertilizer.

Miller acknowledges funding from the Department of Energy, the Smithsonian Institution, Western Michigan University and StatoilHydro.

Biofuels Processing

Researchers try to genetically modify tobacco to produce enzymes for breaking down biomass from forest raw materials. This may lead to a more effective, economic, and sustainable production of biofuels.

A Norwegian-based research project now aims to develop low cost production of industrial enzymes using tobacco plants as a "green factory". Such enzymes may be used in the production of second generation biofuels, and to produce biochemicals that can replace various oil-based products.

"Plants can use CO2 and energy from the sun for free. The whole production process of making the enzymes in plants is cheap, and environmentally friendly," explains Dr. Jihong Liu Clarke from Bioforsk. Tobacco is ideal for this purpose, because it has a good biomass, grows quickly, and can be harvested several times a year.

In California, researchers at the DOE's Molecular Foundry nanoscience research center designed a new material that could pave the way for the adoption of cheaper, cleaner-burning fuels.

Ethanol, the liquid form of the natural gas ethane, is an attractive form of liquid fuel because it burns cleaner and provides greater energy. Unfortunately, making ethanol from ethane requires extreme heat, making it a very expensive fuel. To lower the temperature, the research team created a metal-organic framework (MOF) which speeds up the chemical reaction that turns ethane into ethanol.

In addition to their catalyzing ability, MOFs can also act as a chemical filter. With a specially designed MOF, they were able to produce ethanol at just 167F.