Separacija gnojevke in uporaba frakcij po separaciji – idejna tehnološka zasnova za kmetijo

Kralj, Luka (author), Mihelič, Rok (mentor)

Najbolj razširjeno živinsko gnojilo na svetu je gnojevka, ki se skladišči v gnojnih jamah, lagunah ipd. Iztrebki se po navadi iz hleva odstranijo skozi betonske rešetke ali preko blatnega hodnika, živina pa ima na voljo ležalne bokse, kjer je za dobro počutje živine potrebo redno menjavati steljo. Z namenom zmanjšanja skladiščnih kapacitet in potrebe po velikih količinah stelje se mnogi kmetje odločijo za nakup separatorja gnojevke. Separator gnojevke je kmetijski stroj, ki gnojevko ločuje na trdno oz. čvrsto in tekočo frakcijo. Trdno frakcijo lahko kmetje uporabijo kot steljo za živino. V magistrskem delu je opisano delovanje separatorja gnojevke, njegove prednosti in slabosti, tipi separatorjev itd. Osrednji del magistrske naloge pa je poskus, ki smo ga izvedli na intenzivni živinorejski kmetiji, katera se ukvarja z rejo krav molznic. Povod za poskus je bilo vprašanje, kako se razporedijo hranila iz gnojevke v obe frakciji po separaciji. Na kmetiji smo odvzeli 9 vzorcev, 3 vzorce ne-separirane gnojevke, 3 vzorce tekoče frakcije po separaciji in 3 vzorce trdne frakcije po separaciji. V vzorcih se je analizirala vsebnost osnovnih hranil ter nekaj ostalih lastnosti. Rezultati analiz so pokazali, da je trdna frakcija po separaciji vsebovala največ organske snovi med vzorci, zaradi česar je bilo v trdni frakciji izmerjeno tudi največ skupnega dušika ter skupnega fosforja. Največ amonijevega dušika je bilo v tekoči frakciji. Vsebnosti skupnega kalija pa so bile največje v neseparirani gnojevki ter v tekoči frakciji po separaciji. Glede na zajete podatke o bilanci hranil na vratih kmetije, ima kmetija velike presežke dušika na hektar KZU, presežki fosforja in kalija pa se gibljejo v optimalnem področju. Glede na analize tal, bi lahko kmetija prodala le majhen delež trdne frakcije (do 10%), saj bi lahko ob bolj obsežni prodaji izgubili preveč organske snovi, katero potrebujejo njive.

• Language: Slovenian
• Keywords: separacija gnojevke, gnojevka, tekoča frakcija, trdna frakcija, bilanca hranil
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Year: 2024
• PID: 20.500.12556/RUL-158890
• COBISS.SI-ID: 199740675
• Publication date in RUL: 22.06.2024

Secondary language

• Language: English
• Title: Slurry separation and use of fractions after separation - conceptual technological design for a farm

Abstract

The most common livestock manure in the world is slurry, which is stored in manure pits, lagoons, etc. Excrement is usually removed from the barn through concrete grates or through a corridor, and the livestock have lying boxes, where it is necessary to regularly change the litter for the well-being of the livestock. In order to reduce storage capacities and the need for large quantities of litter, many farmers decide to purchase a slurry separator. A slurry separator is an agricultural machine that separates slurry into solid and liquid fraction. The solid fraction can be used by farmers as bedding for livestock. The master thesis describes how the slurry separator, works, its advantages and disadvantages, types of separators, etc. The main part of the master thesis is an experiment that we carried out on an intensive livestock farm, which raises dairy cows. The reason for the experiment was the question of how the nutrients from the slurry are distributed into the two fractions after separation. On the farm, we took 9 samples, 3 samples of non-separated slurry, 3 samples of the liquid fraction after separation and 3 samples of the solid fraction after separation. The samples were analyzed for the content of basic nutrients and some other properties. The results of the analysis showed that the solid fraction after separation contained the most organic substances among the samples, as a result of which the most nitrogen and phosphorus were also measured in the solid fraction. Most of the ammonium nitrogen was in the liquid fraction. The contents of potassium were highest in the unseparated slurry and in the liquid fraction after separation. According to the collected data on the nutrient balance at the farm, the farm has large excesses of nitrogen per hectare of agricultural land in use, while the excesses of phosphorus and potassium are in the optimal range. According to the soil analysis, the farm could sell only a small proportion of the solid fraction (up to 10%), because with a larger large-scale sale, too much organic matter that the fields need would be lost.

• Keywords: slurry separation, slurry, liquid fraction, solid fraction, nutrient balance