Grain Based Ethanol and its Growth in India !

Grain based ethanol or Grain alcohol is a purified form of ethanol made from the distillation of fermented grain. The ethanol is produced by fermenting sugars in the grain by yeast prior to repeated distillation or rectification. It is also used to refer to any ethanol produced from grain or other agricultural origin.

Grain based ethanol is used for the production of white spirits such as gin and vodka but also as a base for a wide range of flavoured alcoholic beverages. It is a colorless liquid addressed as a ‘neutral spirit’ i.e. bereft of added flavor. The chemical composition of C2H5OH makes it a flammable liquid.

Grain alcohols are known to act as depressants and a neurotoxin to the central nervous system. They find their application in alcoholic beverages, recreational drugs, solvents, antiseptics, fuels, and various industrial purposes.

The Growing Demand for Grain Based Ethanols

One of the factors responsible for the growing acceptance of grain-based alcohol in india is the inconsistency in Molasses’ prices. Until now, Molasses have been traditionally dominant in the production of alcohol in the Indian Made Foreign Liquor (IMFL) market. Now, however, the trend of using grain-based alcohol is exponentially growing. According to Praj industries - one of the leading Ethanol plant manufacturers in Asia, the grain-based variety of all potable alcohol produced in India has grown to 10% from a meager 2% to 3%. It is expected to further reach 22% in the next 5 years. (1)

Is Grain Alcohol 100% Pure?

Grain alcohol is commonly bottled in two versions, 75.5 percent ABV and 95 percent ABV. There is no 100 percent ABV grain alcohol for human consumption because of azeotropic effects during the distillation process. Such concentration is considered too easy for people to get alcohol poisoning.

Abundant Availability of Grains in India Makes it A Popular Choice

Alcohol from grains is found to be better in quality, but more expensive than the ones made from molasses. However, grain-based ethanol plants can find additional income source in one of the byproducts of grain-based distilleries - the animal feed. This has prompted more companies to set grain ethanol plants. This will also mean that we can get better quality alcohol.

As oil companies increase the use of ethanol for blending with petrol, prices of molasses-based ethanol have increased. As a result, the IMFL manufacturers frequently switch between grain-based and molasses-based alcohol depending upon its prices.

The government plans to allow food grains during surplus production years to be used for the production of ethanol that can be blended with petrol, in an attempt to broaden the availability of raw materials needed for Bioethanol production.

Pune-based Praj Industries, leaders in Industrial production of ethanol, have covered 80% of the dryer market in the past few years. The dryer technology, used for drying the wet waste generated by the grain-based distilleries has made it possible for the distilleries to cross-subsidize the production cost of grain alcohol.

How Enogen and Cellerate can boost ethanol production?

With the growing significance of ethanol plants, newer and competitive ways are being explored to facilitate ethanol processes, making it more productive. Enogen Corn Enzyme is one of the latest in-seed techniques that is specifically designed to enhance the overall ethanol production. The modern biotechnology is directed towards infusing top-grade alpha amylase enzyme directly in the grain, eliminating the need to add liquid alpha amylase. This results in reduced production costs and improved process efficiency, thus adding value to ethanol plants and yielding desirable benefits to the corn ethanol producers.

How does Alpha-amylase enzyme work?

Alpha-amylase enzyme is a key ingredient in ethanol production. Corn seeds rich in this enzyme can be highly beneficial for ethanol plants.

The enzymes help ethanol plants reduce the viscosity of corn mash and eliminate the requirement of adding a liquid form of the enzyme. This yields incredibly high levels of solids loading in liquefaction and fermentation tanks, leading to increased throughput and yield. Use of Enogen technology with alpha-amylase enzyme also ensures a significant reduction in natural gas, electricity and water usage.

Cellerate Process Technology and Cellulosic ethanol

Cellerate process technology is a revolutionary procedure that helps ethanol producers to extract increased amount of ethanol from the same kernel of corn. It employs innovative procedure to convert corn kernel fiber into cellulosic ethanol. With cellerate technology installed in ethanol plant infrastructure, the biofuel industry can witness multifold increase in their produce.

The technique does not require any changes to be made in the conventional process of obtaining ethanol from molasses. It leverages the existing infrastructure and offers significant advantages to your plant. It allows pre-treatment in the fiber that facilitates whole stillage processing, eliminating the need to separate all the fiber and starch.

Benefits of Cellerate

Cellerate is a diverse process technology which significantly increases total production by utilizing pre-existing assets like feedstock receiving and storage, product separation and product storage. Besides enabling additional throughput from a dry grind ethanol facility, the process also offers the following benefits:

lAdds value to protein; feed co-products with higher protein content

lIncreases distillers corn oil production

lCreates cellulosic ethanol

lProduces low carbon intense ethanol

Cellerate and Enogen corn when used together can offer optimum benefits to Industrial production of ethanol, including increased throughput and yield with reduction in production cost.

In light of increased fuel prices, dependency on other countries for fuel needs and detrimental impact on the environment due to harmful emissions, ethanol industry needs a tremendous boost. Employing modern and innovative techniques like Cellerate and Enogen in ethanol plants can play an important role in addressing these issues.

Production of Ethanol using Dry Milling .

Ethanol is produced from biomass, primarily by fermenting the glucose derived from sugars obtained from sugar cane, sugar beet, and molasses, or starches obtained from corn, wheat, grains or using cellulose as raw materials. Industrial production of ethanol is majorly carried on using either the wet mill or dry mill process. Wet milling process involves separating the grain kernel into its constituents of germ, fiber, protein, and starch, before fermentation. Whereas in the dry mill process, the entire grain kernel is directly ground into flour. The starch in the flour is converted to ethanol during the fermentation process, creating carbon dioxide and distillers’ grain. In the USA, around 67% of ethanol is produced by the ethanol industry using the dry-grinding process. The various procedure involved in the ‘dry-milling’ process is discussed below.

Mash Formation

Screening is used to remove debris from the grains mass. These filtered kernels are then ground and mixed with water to form a slurry called ‘mash’.

Cooking

The mash is cooked, followed by the addition of enzyme which converts the starch into sugar. Yeast is then added to ferment the sugar which results in a mixture of ethanol and solids. The ethanol is extracted using the distillation & dehydration process. The solid which remains is dried to find its application as a distiller’s dried grain soluble or DDGS. DDGS is popularly used as a high-protein supplement in cattle, swine, poultry, and fish diets. Starch usually comprises of 25-30% amylose and rest is amylopectin. In order to metabolize this starch, yeast is used break it down into glucose, prior to fermentation.

Liquefaction

The slurry is then pumped through a pressurized jet cooker at high temperatures and held for a few minutes. The mixture is then cooled using a condenser. After the condensation cooling, the mixture is held for a few hours at a predefined temperature to give the alpha-amylase enzyme time to break down the starch. The slurry is then heated to reduce viscosity and to provide mechanical shearing to rupture starch molecule, especially of high molecular weight. The mash is further liquefied for at least 30 min to reduce the size of the starch polymer. This dextrinized mash is further cooked to facilitate the addition of glucoamylase to convert liquefied starch into glucose. To accomplish the saccharification of starch to glucose, glucoamylase is added in enough quantity.

Saccharification

Once inside the fermentation tanks, the dextrins are broken down to form simple sugars. Yeast is then added to convert the sugar to ethanol and carbon dioxide. The mash is afterward allowed to ferment for 48–72 hours, resulting in a mixture that contains about 10% ethanol as well as the solids from the grain and added yeast.

Fermentation 

After saccharification, cooling is done and mash is transferred to fermenter and yeast is added. The whole process requires 48-72 hours and can concentrate up to 10-12% of ethanol. CO2 released during this process can be captured and sold for the use in carbonated soft drinks, dry ice, and some beverages industries.

Distillation and Dehydration

Distillation is the process of separating ethanol from the solids and water in the mash. The fermented mash is pumped into the distillation columns where additional heat is added. The columns utilize the differences in the boiling points of ethanol and water as a milestone to boil off and separate the ethanol. By the time the product stream is ready to leave the distillation columns, it contains about 95% ethanol by volume. To carry out the separation of the remaining 5% water from ethanol, It is passed through a molecular sieve. This step produces 100% pure ethanol.