Consideration of Distillery Waste Water as a Bio-stimulant as defined in the Fertilizer (Inorganic, Organic or Mixed) Control Order, 1985 vide S.O. No. 882(E) dated 23-02-2021 and permitting use accordingly.
The Ministry of Agriculture and Farmers Welfare, Government of India has recently issued an amendment to the Fertilizer (Inorganic, Organic or Mixed) Control Order, 1985 vide S.O. No. 882(E) dated 23-02-2021.
The said amendment recognizes a new class of fertilizers designated as ‘Bio-stimulants’ which are defined as a substance or microorganism or a combination of both whose primary function when applied to plants, seeds or rhizo-sphere is to stimulate physiological processes in plants and to enhance its nutrient uptake, growth, yield, nutrition efficiency, crop quality and tolerance to stress, regardless of its nutrient content, but does not include pesticides or plant growth regulators which are regulated under the Insecticide Act, 1968 (46 of 1968)”.
Standards for use have been prescribed along with permissible limits for Heavy metals and Pesticides.
It appears to be a big step taken towards sustainable environmental management as it promotes the use of effluents for agriculture subject to their meeting the criteria established under the Fertilizer Control Order. A detailed process for study and evaluation has been drawn up before grant of permissions for manufacture or sale of bio stimulants.
This amended Fertilizers Control order would throw up immense opportunities for the sustainable management of effluents which may possess the capacity to stimulate physiological processes in plants and to enhance nutrients uptake, growth, yield, nutrition efficiency, crop quality and tolerance of stress.
Of considerable importance here appears to be the utilization of distillery spent wash in Agriculture which is a well established practice.
Many authors have classified spent wash as a dilute organic fertilizer with 7 to 9% solids and 90 to 93% water. More than 75% of the solids are organic in nature and about 25% are inorganic. It is fairly rich in Potassium. The occurrence of nitrogen in a mostly colloidal form allows it to behave as a slow-release fertilizer and better than any inorganic source of nitrogen. The presence of phosphorus in the organic form has also enabled a better availability.
Spent wash also contains large amounts of essential elements such as Copper (Cu), Manganese (Mn) and Zinc (Zn). It also contains 29.1% reducing sugar, 9.0% protein, 1.5% volatile solids, 21.0% gums, 4.5% combined lactic acid, 1.5% combined organic acids and 5.5% glycerol. This spent wash, being loaded with organic and inorganic compounds could bring remarkable changes in the physical, chemical and biological properties of soils and thus, significantly influence the fertility of soil. Organic compounds extracted by alkaline reagents have been found to be humic in nature and similar to those in soil. They also do not contain any toxic elements or compounds.
The Central Pollution Control Board has also been earlier supporting the utilization of Distillery Spent Wash in Agriculture through Ferti-irrigation and One Time Controlled Land application but is currently discouraging it, not due to any technical reasons but due to difficulties faced in its management.
Agricultural utilization of waste water offers a low cost alternative where the manure and irrigation value of spent wash are utilized and savings generated in fertilizers and water use. The secondary and tertiary treatment systems including concentration and incineration for distillery effluents are highly water and carbon intensive and climate unfriendly and may also result in raising the cost of production by Rs. 8-10 Per liter of Alcohol.
The application of spent wash as manure has resulted in increased yield of crops, increased root and shoot length, leaf area index, chlorophyll content and pod formation. Substantial increase was also recorded in case of germination, oil and protein content of crops, nutrient availability of soil, nutrient uptake by crops and mineralization of soil. It has also enhanced the nutrient availability and uptake without any post-harvest detrimental impacts on the soil texture, chemistry and biology.
In view of the recognition of ‘Bio-stimulants’ as fertilizers and the Fertilizer Control order prescribing standards for use of these ‘Bio-stimulants’, ‘Distillery Spent’ Wash could be examined to be considered as a bio-stimulant as defined under the Fertilizer Control order and its use permitted accordingly.