best available technologies for manure treatment - Baltic Green Belt

Best Available Technologies for manure treatment baltic sea 2020
Best Available Technologies for manure treatment baltic sea 2020
ANNEX E: TABLES WITH SHORT DESPRIPTION OF LIVESTOCK MANURE TREATMENT TECHNOLOGIES
Best Available Techniques for manure treatment - for intensive rearing of pigs in Baltic Sea Region EU Member States Technical Report "Best Practice Manure Handling, Phase 2"
conditions.
3. Additives for changing the physical properties of the manure: The objective of the additive is to make
the manure easier to handle. These additives are probably the most used and their effects are well
known. Their use results in an increase in manure flowing, an elimination of superficial crusts, a
reduction of solved and suspended solids and a reduction in the stratification of the manure. However,
these effects were not demonstrated in every comparable case.
Their application might make the cleaning of the manure pits easier, and thereby might shorten the
cleaning time required and allow a saving in water and energy consumption. Moreover, since the manure
is more homogeneous, it eases the manure’s agricultural use (better dosing).
4. Additives for increasing the fertilising value of the manure: This effect is in fact derived from the
reduction in NH
3
emissions, thereby keeping this N retained in the manure (in many cases through the
increased synthesis of the microbial cells, giving higher levels of organic N).
5. Additives for stabilising pathogens micro-organisms: There are many different microorganisms in
manure, part of these contribute to the gaseous emissions and odours. It is also possible to find faecal
coli forms and Salmonella and other pig pathogens, virus, eggs of flies and nematodes in the manure.
Usually, the longer the storage period the higher the decrease in pathogens, because of the different
requirements of temperature and pH. The pH decreases within the first month of storage (from 7.5 to
6.5 because the microbial synthesis of volatile fatty acids) which has a negative effect on pathogens
survival. Some of the manure additives have been designed to control them, especially the eggs of flies.
Types of manure additives
masking and neutralising agents: These are a mix of aromatic compounds (heliotropin, vanillin)
that work by masking the manure odour. The agent is easily destroyed by manure microorganisms.
Its actual efficacy is questionable.
adsorbers: There are a large number of substances that have demonstrated an ability to adsorb
ammonia. Some types of zeolites called clinoptilolites have shown the best effect, being added
either to the manure or to feed on ammonia emission. They are also able to improve soil structure
and have the added benefit that they are not toxic or hazardous. Peat gives similar results and is
also sometimes used.
urease inhibitors: These compounds stop the reaction described earlier preventing urea from being
transformed into ammonia. There are three main types of urease inhibitor:
1. phosphoramides: applied directly to the soil. Show a good effect. They work better in acid
soils, but could affect soil micro-organisms
2. yucca extracts (Y. schidigera): many trials have been done to assess its potential but the
available information is controversial, showing good results in some cases, but no effect
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