Logo Module 5: Animal Manure and Process-Generated Wastewater Treatment By Saqib Mukhtar

Logo Certified Nutrient Management Planning5-2 Introduction The purpose of this module is: To describe principles of manure and wastewater treatment. To discuss current and emerging technologies that treat and stabilize manure and wastewater.

Logo Certified Nutrient Management Planning5-3 Waste Stabilization The physical and/or chemical process of breaking down and converting waste constituents to homogeneous and reusable end products, with reduced odors and volatilization of organic compounds

Logo Certified Nutrient Management Planning5-4 Principles Used in Manure Treatment Gravity settling Mechanical separation Flocculation Aeration Anaerobic processes Natural systems

Logo Certified Nutrient Management Planning5-5 Gravity Settling One of the first processes used to treat wastewater Removes larger solids (mineral particles and biomass) by reducing flow velocity Consists of shallow settling tanks or basin with sloped access area Handles large amounts of solid and organic matter

Logo Certified Nutrient Management Planning5-6 Settling Tank

Logo Certified Nutrient Management Planning5-7 Settling Basin

Logo Certified Nutrient Management Planning5-8 Gravity Settling Advantages Load reduction for subsequent treatment processes Reduction of clogging in pumps and pipes Disadvantages Large size requirements High construction and operating costs

Logo Certified Nutrient Management Planning5-9 Mechanical Separation Process consists of solids removal by:  Inclined screens, self-cleaning screens, presses, centrifuge processes, and rapid sand filters  Used for animal manure treatment  Reduction in carbon, nitrogen, and phosphorous and heavy metals loads to subsequent treatment units

Logo Certified Nutrient Management Planning5-10 Mechanical Inclined Screen Separator

Logo Certified Nutrient Management Planning5-11 Mechanical Press Separator

Logo Certified Nutrient Management Planning5-12 Mechanical Separation Advantages Odor control Easy removal and disposal of solids Separated solids have many end uses. Disadvantages High initial set-up cost Proper maintenance required

Logo Certified Nutrient Management Planning5-13 Flocculation Removal of solids and suspended particles by adding flocculating agents Treated particles removed by filtering or settling Alum and lime are commonly used flocculating agents.

Logo Certified Nutrient Management Planning5-14 Flocculation Advantages Removal of very fine particles Increase in the agronomic value of the sludge Disadvantages Process is expensive Additional manage- ment of large amounts of removed sludge

Logo Certified Nutrient Management Planning5-15 Aeration Used to reduce the biological oxygen demand (BOD) in water Used in waste storage and treatment structures to reduce odor Aerators are used to provide continuous or partial aeration.

Logo Certified Nutrient Management Planning5-16 Complete Aerating Unit

Logo Certified Nutrient Management Planning5-17 Floating Aerator Unit

Logo Certified Nutrient Management Planning5-18 Aeration Advantages Odor control Satisfies high oxygen demands Disadvantages High energy requirement Frequent cleaning required due to enhanced sludge accumulation

Logo Certified Nutrient Management Planning5-19 Anaerobic Processes Natural processes of degradation in the absence of oxygen Take place in deep lagoons or closed digesters Used in the treatment of livestock and poultry waste

Logo Certified Nutrient Management Planning5-20 Anaerobic Processes Advantages BOD and solids reduction Reduced sludge production Methane byproduct can be used as fuel. Disadvantages Slow process Sensitive to temperature and pH changes Odor problems

Logo Certified Nutrient Management Planning5-21 Natural Systems Use natural mechanisms to reduce BOD and suspended soils Treatment systems include:  Constructed wetland systems  Vegetative filter strips  Overflow plots

Logo Certified Nutrient Management Planning5-22 Advantages and Disadvantages Advantages Reduction in nitrogen levels Odor reduction Disadvantages Large area requirement

Logo Certified Nutrient Management Planning5-23 Vegetative Filter Strip

Logo Certified Nutrient Management Planning5-24 Manure Utilization and Treatment Technologies Land applications Anaerobic lagoons Anaerobic digesters Composting Vermicomposting

Logo Certified Nutrient Management Planning5-25 Manure Utilization and Treatment Technologies (continued) Mortality composting By-product recovery Energy conservation Constructed wetland systems

Logo Certified Nutrient Management Planning5-26 Land Application Terminal receiver of treated and untreated manure and wastewater Effective disposal option for livestock and poultry producers Given proper practices and application guidelines, effective plant nutrient supply

Logo Certified Nutrient Management Planning5-27 Land Application Advantages Reduction in fertilizer costs Better soil quality Low cost Disadvantages Odor problems Large land area required Nutrient regulations

Logo Certified Nutrient Management Planning5-28 Anaerobic Lagoons Waste stabilization through anaerobic biological activity Used to store large amounts of wastewater Efficiency depends on lagoon design and climatic conditions

Logo Certified Nutrient Management Planning5-29 Anaerobic Lagoon

Logo Certified Nutrient Management Planning5-30 Anaerobic Lagoon Advantages Can store large amounts of waste Recycles flush water Removes large amounts of nitrogen Disadvantages Large land area required Odor problems Safety concerns Sludge management

Logo Certified Nutrient Management Planning5-31 Anaerobic Digesters Similar to anaerobic lagoons but smaller in size Normal operating temperatures between 95°F- 165°F Methane and carbon dioxide byproducts

Logo Certified Nutrient Management Planning5-32 Anaerobic Digester

Logo Certified Nutrient Management Planning5-33 Anaerobic Digestion Advantages Methane as an alternative fuel Increases solid decomposition Small land area required Odor control Disadvantages Careful management required Safety concerns– methane is explosive High costs Does not reduce nutrients such as N, P, and K

Logo Certified Nutrient Management Planning5-34 Composting Aerobic process used to stabilize organic matter Volume reduction of between 25%-50% Stabilized end product (humus) is high in organic matter and nutrients

Logo Certified Nutrient Management Planning5-35 Aerated Composting Containers

Logo Certified Nutrient Management Planning5-36 Composting Advantages Odor control Controls pests, pathogens, and weed seeds Increases soil quality Marketable by- product Disadvantages Careful management required Additional costs Space requirements

Logo Certified Nutrient Management Planning5-37 Vermicomposting Process uses earthworms and microorganisms in the conversion of organic wastes to humus End product used as fertilizer for plants Techniques include boxed and outdoor windrows and automatic systems

Logo Certified Nutrient Management Planning5-38 Vermicomposting Advantages Reduces lagoon loading Odor control Nutrient reduction Worms used as animal and aqua- culture feed Disadvantages Careful management required Space requirements Additional costs

Logo Certified Nutrient Management Planning5-39 Mortality Composting Described by the Ohio State University Extension as “above ground burial in a bio-mass filter with pathogen kill by high temperature” Process used to dispose of dead livestock and poultry Additional materials added to increase porosity and as a carbon source

Logo Certified Nutrient Management Planning5-40 Large–Carcass Composting

Logo Certified Nutrient Management Planning5-41 Mortality Composting Advantages Disposal of dead animals Odor control Kills pathogens Marketable byproduct Disadvantages Careful management required Regulatory concerns Initial setup can be expensive

Logo Certified Nutrient Management Planning5-42 By-product Recovery Processing the end products into value-added material End products include spent biomass, sludge, and composted manure Products rich in C, N, P, and minerals

Logo Certified Nutrient Management Planning5-43 Nursery Crops Raised on Treated Animal Manure

Logo Certified Nutrient Management Planning5-44 By-product Recovery Advantages Marketable byproduct Feed supplements Improve soil quality Disadvantages Careful management required Time and space constraints

Logo Certified Nutrient Management Planning5-45 Energy Conservation Use of alternative treatment methods to derive energy as a byproduct Combustion of manure and coal, methane gas produced from anaerobic digestion

Logo Certified Nutrient Management Planning5-46 Advantages and Disadvantages Advantages Marketable byproduct Use as an alternative fuel Used with other manure treatment facilities Disadvantages Careful management required Safety risk

Logo Certified Nutrient Management Planning5-47 Constructed Wetland Systems Similar to natural wetland systems Waste pretreated to reduce organic loads and solids content Typical wetland systems include surface flow systems and subsurface systems.

Logo Certified Nutrient Management Planning5-48 Constructed Wetland System

Logo Certified Nutrient Management Planning5-49 Constructed Wetland Systems Advantages Inexpensive Low maintenance Aesthetically pleasing Disadvantages Large area requirements High monitoring requirements

Logo Certified Nutrient Management Planning5-50 State of the Art Current technologies being developed include: Addition of polymers to improve solids separation from a liquid stream Aerated treatment basins as an alternative to anaerobic lagoons Artificial floating layers for odor control

Logo Certified Nutrient Management Planning5-51 Electrocoagulation Destabilization of suspended, dissolved particles by passage of electrical current between electrodes Causes contaminants to form precipitates Removed by secondary separation techniques

Logo Certified Nutrient Management Planning5-52 Advantages and Disadvantages Advantages Removes complex organics Can process multiple contaminants Can destroy harmful bacteria and viruses Lesser sludge production Disadvantages Disposal challenges due to aggregation of precipitated solids Initial setup expensive and operating costs can be high Careful, specialized management required