SUSTAINABLE UTILISATION

OF SPENT WASH IN

AGRICULTURE – A CASE FOR

OTCLA

by:

Dr. Yashpal SinghEnvironmental Counselor

THE HIDDEN WEALTH

Currently about 45 billion liters of S.W. produced in

the country

Non Toxic, contains plant nutrients.

Bio methanated waste water can produce 85000

tonnes of biomass annually

24500 Tons Potash (1.55 million hectare) Double

Cropping

12500 tons of Nitrogen (0.13 million hectare)

2100 Tons of Phosphorous (0.025 million hectare)

Also Zinc, Iron, Manganese, Organic Compounds,

Vitamins, Proteins, Growth promoters, biocides etc.

Treatment

• Starting from lagooning various technology

options evolve with consensus.

• Biomethanation

• Biomethanation and secondary treatment followed

by irrigation or disposal in inland surface waters

• One Time Controlled Land Application

• Composting with or without biomethanation

• Activated sludge treatment

• Concentration and incineration

• Anaerobic digestion followed by evaporation and

composting.

• Reverse Osmosis

• Recovery of potash

• Most of these technologies recognized as viable

technologies by the Regulatory bodies.

AIDA prays before NGT to allow mix of technology.

NGT agrees. Asks for guidelines on ZLD and Online

Water security a vital issue

Sugar Cane likely to suffer a loss of 30% in India

because of water. Climate change projections.

Effluents irrigation utilise the fertilization and

irrigation potential of waste.

Replaces chemical fertilizers. Provides essential

nutrients like NPK.

Saves recipient systems from pollution.

CPCB document recognizes aerobic composting,

vermi-culture, ferti irrigation and one time controlled

land application as emerging technologies.

Use of Waste Waters in Agriculture

45 billion litres

500 crores in terms of NPK and S

150 crores for micro nutrients and organics

100 crores saving in Environmental costs

100 crores in terms of loss to fisheries

500 crores savings in water treatment costs

100 crores in Public health

100 crores in Landscape costs

Energy savings in secondary and tertiary systems 1400 crores

In Gujarat, waste water supports annual agriculture production

worth Rs. 26.6 crores.

Economics

Increase yield 45 to 100%

Meets long term requirement of nutrients

Beneficial for soil flora/fauna

Conjunctive use preferred

Effect on crops

Impact on Ground Water

Continued use has not impacted ground water.

Need to be constantly monitored

Impact on Soil

Improved physical/chemical properties

Stable aggregates, moisture retention, water

holding, aeration

Improvement in soil carbon and potash

Post harvest soil not known to exhibit

adverse affects.

Chemical Properties

Increases pH, EC, Cations, Anions, SAR, KAR,

exchangeable K, Na, Ca and Mg, nitrogen

availability, soil nitrate, phosphorous.

Damaging impacts at doses 300 m3/ha or lower not

observed

Biological Properties

Improves biological activity

Higher counts of bacteria, Actinonomycetes,

Azetobacter and Fungi.

Colour of effluent degrades

Growth promoting substances GA/IAA reported

Incidence of plant pests decreases

Emergent technology

20 to 60% increase in yield. Upto 200 m3/ha twice a year.

Increases soil fertility

Some states following practice

CPCB feels it is difficult to manage

Regulatory authorities do not permit

Presown Land Application

CPCB and Technology Options

Recommends use in Agriculture through CREP

Recognizes these as emerging technologies

Recognizes use of effluents in agriculture in guidelines

Industry allowed to practice any technology

Standards still allow disposal in water or on land.

Discourages use of these technologies in May 2008.

Professes co-processing

Initiates study on utilisation in Agriculture in 2007-2008.

Report awaited.

Principal Scientific Advisor to Government of India brings out

report in 2015 on Green Chemistry initiatives. Supports

agriculture utilisation.

Incineration not regarded viable by CPCB.

Co-processing is not viable with only, Cement and 11 TPP’s.

Can take care of only 24/50 KLD of spent wash in a Cement

plant of 3000 TPD.

Involves change in Kiln design and special APCS.

Evaporation and ZLD likely to affect minimum flows

Self Cleansing capacities

May trigger drying up of rivers due to reverse recharge

Irrigation Water availability

Availability of water for competing uses

Promote Increased use of Chemical fertilisers

Increased generation of power

May 2008 minutes recommend change to incineration only if

existing standards are not being met

Introduction of ZLD likely to introduce ecological

consequences

May need an environmental Assessment and E.C.

Land application the most efficient means of recycling water

and nutrients.

Needs efficient irrigation management plan and regulated use

in rainy season.

National Water Quality Management

Strategy for Australian Wineries and

Distilleries recognizes-

CSR Distilleries, Victoria

Two main product streams, Ethanol and fertilizers

Bio dunder blended with Nitrogen, Phosphorous, Sulphuric

acid to give Liquid one shot.

Bottled and sold, crop specific constitution

Certified as organic and granted Beneficial use status by EPA.

Beneficial to soils and crops.

Distillery converts from a Pariah to a welcome

industry

Change in process technology to bio-still resulted in

reduced steam (by 30%) and water consumption (by

70%)

Improved plant productivity, product quality

Turned Pollutant into saleable product . 100% of

spent wash is being recycled in this market.

Ended complaints. Instead of closing, Industry

thrives.

CSR employees given the Annual Environment

Award by the Australian Chemical Industry Council

in 1992.

Bureau of Sugar Experimental stations assisted by

conducting field trials and determining optimum

rates.

CSR Distilleries (Contd)

BRAZIL

Land application the most efficient means of recycling water

and nutrients.

Vinasse BOD 75330, COD 97400, TDS 33680, NPK of

885:188:3852 mg/L

Fully recycled to the fields for ferti-irrigation

Mills have applied vinasse to 70% of their crop areas

Tanks, Trucks and Sprinklers

No damaging impacts on soil at doses lower than 300 m3/ha

Doses in excess of 400 m3/ha could be harmful

Considered as an organic fertilizer and released for organic

Sugar production

A technical Standard by the Office of Secretary of

Environment (Sao Paulo) regulates application eg. Risk areas,

permitted doses and technology.

Ferti irrigation program 1996

35% Federal Funds, 15% State Funds and 50%

project beneficiaries

Covers Ferti-irrigation equipments and technology

assistance.

40% Water, 32% energy costs reduction achieved.

18% harvested area, 30% production, 28%

exportable farm produce increments

IRR of 16% including all costs and 25% return in

farmers investment.

Mexico

MEXICO and other Countries

Other Countries

In Romania, Vinasse is applied to permanent grass lands at

4 to 7 tonne/ha in a 1:5 water dilution. Yield increased upto

81% over control.

Improved nutritive value of fodder.

In Ireland slops are concentrated in MEE and processed to

Pot Ale for agricultural use.

Spent wash is rich in nutrients and good for crops

and soils. Efforts should be made to fruitfully utilise

the spent wash for agricultural applications.

Controlled land application of BMSW may be

beneficial for reclamation of sodic soil.

Presowing application of BMSW followed by two

irrigations can leach out soluble salts from surface

soil for better germination and growth

Report recommends long term comprehensive

research projects on aspects of doses, soil types,

permeability etc.

Information should be collected on international

practices.

Green Chemistry Initiatives

On Incinerator

BMSW rich in potash and wasting nutrients not desirable

Country depends on import of Potash

Recovery of Potash from SW by evaporation and incineration

would not be viable.

Even after incineration, the safe disposal of ash generated

with high concentration of inorganic salts is a problem

Before insisting on incineration there is a need to evaluate

system.

Green Chemistry Initiatives

Use BMSW only

BOD not to exceed 7000 mg/L, pH not more than 7

30 days storage during monsoon

Command area within 20 kms

Use either pipeline or tanker

Sampling and monitoring

Detailed utilisation plan

Apply uniformly on land 20 days prior to sowing and

ploughed before raising the crop.

Dosage defined

Soil pH not to exceed 8.5 and ECe 4 millimhos/cm

Increase in BOD, TDS and No3 not more than 3

mg/L and 10 mg/L.

Install piezometers

MOU with University

OTCLA Protocol

Acidic Raw Spent Wash could be utilised

300 Kl/ha recommended for soils beyond 8.5 pH. Equivalent

to 34.40 tonnes/ha of Gypsum

Untreated spent wash should not be used for a pH of less

than 8.5

Distillery SW alone or in combination with gypsum is effective

Time log of one month between raw spent wash application

and sowing next crop

BMSW is not effective in reclaiming calcareous soils

Sodic Soil Reclamation

THANK YOU