UTILIZATION OF BLOTONG AS AN ACTIVATOR ORGANIC FERTILIZER

Utilizing microbial activity to transform organic waste into material with the characteristics of soil, composting is a method of biological treatment of organic waste. Sugar factory filter cake contains minerals like carbon, nitrogen, phosphate, calcium


INTRODUCTION
Nowadays environmental problems are often caused by waste that is not handled properly.In addition, the large volume of waste reduces environmental aesthetics, disrupts people's lives if it is not handled immediately.The Candi Baru Sugar Factory in Sidoarjo produces solid waste in the form of filter cake of ± 60 tons/day or 3% sugar cane, dry ash 28.8 tons/day and wet ash ± 27 tons/day (report of PG Candi Baru Sidoarjo waste 2011).
B lotong is the waste with the highest level of pollution and is a problem for the sugar factory and the community.This waste is usually disposed of into rivers and causes pollution, because in the water the organic matter in the filter cake will naturally decompose, thereby reducing oxygen levels in the water and causing the water to be dark and smell bad (Purwaningsih 2011).However, blotong has properties that support the improvement of soil properties, including high water holding capacity, low unit weight, porous and high CEC.Blotong shows great potential to be used as a source of organic matter without disturbing plant growth (Rajiman 2008).
Meanwhile, the use of filter cake as organic fertilizer is still not maximized and its users are limited, this is because the processing of filter cake waste into organic fertilizer can still be said to be perfunctory, it has not been handled using a good and correct process so that the organic fertilizer it produces is still not perfect, and the lack of knowledge of farmers about the benefits of using organic fertilizer from filter cake (Widodo 2009).Meanwhile, in the North Medayu area there are lots of piles of organic waste, especially garden waste (leftover leaves).This will reduce the aesthetics of the environment.So far, residents have been burning the garden waste.Combustion can cause air pollution and interfere with breathing.From these things, the idea arose to utilize these wastes into something that has benefits and also has economic value, namely to be used as material for making organic fertilizer.
This study utilized the solid waste of PG Candi Baru Sidoarjo in the form of cake and garden waste in the North Medayu area, with the aim of looking at the effect of applying filter cake as an activator on the speed of decomposition of garden waste and its effect on compost quality and to find out which aeration method is most effective in speeding up the process.decomposition .The benefit of this research is to add insight into how composting techniques and their contribution to minimizing the volume of existing waste and the results of organic fertilizer from this research can be utilized in fertilizing the soil.

Blotong
Blotong or filter cake is sediment from dirty sap in the sap purification process which is filtered in a rotary vacuum filter .On average, 3.8% of sugar cane is produced, or around 1.1 million tonnes of blotong per year (sugar cane production in 2011 was around 28 million tonnes).The production of blotong reaches 3.5-7.5% of the weight of milled sugarcane.According to Triwahyuningsih and Muhammad, the properties of blotong that support the improvement of soil properties include high water holding capacity, low unit weight, porous and high CEC.Blotong shows great potential to be used as a source of organic matter without disturbing plant growth (Rajiman 2008).
Based on the results of a study by Mudhoo et al (2011) which mixed the filter cake with vegetable waste and bagasse to be used as fertilizer, it turned out that the filter cake showed potential to be used as an ingredient for making organic fertilizer and the filter cake could be combined with other ingredients such as bagasse, vegetable waste and other waste containing cellulose and lignin.
Based on Bhosale's research (2012) which studied the physico-chemical characteristics of the organic matter in the blotong and its effect on the capacity or power of the soil to hold water, it shows that fresh blotong cannot be directly used as fertilizer because it will make the physical properties of the soil worse.extraction or composting process.
The results of the study show that the extraction of organic matter in blotong can be seen significantly to the physical structure and quality of blotong and helps increase the capacity of the soil to hold water to increasing rice production can also slow down the aging of rice leaves.

Garden Waste (Leaf Remains)
The substance of garden waste comes from natural constituent elements, so this waste is easily decomposed by decomposing bacteria so that it is easily destroyed and becomes a soil-forming element that is very fertile and useful for soil fertility.Examples of this waste are leaves, food scraps, fruit peels, etc. (Sanggilora 2012).
Composting is the decomposition of organic matter into simpler organic matter by microorganisms so that the simpler organic matter can be used as fertilizer to improve soil structure and add nutrients to the soil.

METHOD
The method to be used in this study is to set garden waste as a control weighing 3 kg.The independent variables are the addition of filter cake which is varied into 1, 2, 3 and 4 kg, as well as the aeration method which is divided into manually and using an aerator, aeration using an aerator is divided into 3 doses, namely 1.8 l/min/kgVs or equivalent to 0 .1 bar, 2.7 l/min/kgVs or equivalent to 0.15 bar and 3.6 l/min/kgVs or equivalent to 0.2 bar.As the dependent variable is the C/N ratio.
The stages of this research were preparing research tools and materials, conducting preliminary tests including testing temperature, pH, water content and C/N ratio for each material, then weighing the weight of each material and then mixing it in the reactor tub.After that, a preliminary test was carried out on each mixture.
During the composting process, aeration and overturning of the heap is carried out every 3 days, measuring temperature every day, measuring pH once every 3 days, counting bacterial colonies, measuring water content and C/N ratio once a week.The composting process is limited to approximately 3 weeks, then the C/N ratio data is processed using graphical statistics with a linear formula and Anova statistical tests using Minitab 14 software.Conclusions are drawn from the statistical test results.

RESULTS AND DISCUSSION
The results of the initial characteristic analysis for blotong and garden waste can be seen in table 1 below: Temperature dynamics is an indicator of the dynamics of microbiological activity in composting.Therefore, the temperature change profile also describes the characteristics of the ongoing composting process, and even becomes a parameter of compost maturity (Wahyono 2008).
The temperature rises and microorganisms quickly become present in the compost during the warming stage, also known as the mesophilic stage.Mesophilic microorganisms are responsible for reducing the particle size of organic matter in order to increase the material's surface area and speed up the composting process.They live at temperatures between 10 and 45 degrees Celsius.The second stage, known as the thermophilic stage, is characterized by the presence of thermophilic microorganisms in compost piles.These microorganisms live at temperatures ranging from 45 to 60 degrees Celsius and are tasked with consuming carbohydrates and proteins in order to facilitate the rapid breakdown of compost materials (Cahaya, 2009).

Temperature Conditions During the Composting Process
During the composting process, temperature changes occur.Each reactor reached a peak temperature on the second day until the fourth day, this shows that there is energy released by microorganisms in the form of heat.This energy is a product of the carbonization process.

pH Conditions During the Composting Process
In the composting process, the degree of acidity (pH) plays an important role in the activity of microorganisms, microorganisms can live and develop at a neutral pH in the range of 6.5-8.If the pH in the heap of composted material is high or the atmosphere is alkaline, microorganisms cannot grow and develop so that the composting process composting is slow.And if the pH is low or the atmosphere is acidic, it will trigger the growth of pathogenic bacteria and fungi which will actually interfere with the growth of decomposer microorganisms and cause the compost heap to smell bad.
During the composting process, the pH of each compost reactor was in a neutral condition, which was in the range of 6.5-8.This was due to the periodic turning of heap and aeration.

Moisture Content Conditions During the Composting Process.
In the composting process, the parameter that is measured is the water content, because water content is one of the environmental factors that affect the activity of microorganisms in decomposing organic matter.Water is a nutrient solvent factor and protoplasmic cells.Water is produced during the composting process by microorganisms in the form of leachate and some is lost due to evaporation into the air stream.
At the beginning of mixing the materials to be composted the water content was the same, namely ± 20.2%, but then in the first week it tended to decrease.Then in the following weeks there was an increase, according to Polprasert (1996), an increase in water content occurred due to the production of leachate by microorganisms that decompose organic matter, where when decomposing microorganisms decompose organic matter it is accompanied by an increase in temperature, release of CO2 and water vapor, and changes in-changes according to Indriani ( 2002): 1. Carbohydrates, cellulose, hemicellulose, and lignin into CO2 and H2O 2. Egg white substance (protein) is converted into ammonia, CO2 and H2O (Pradana 2007).
In the third week, the percent water content of each reactor is no more than 50%, which is the maximum limit for the percent water content according to SNI 19-7030-2004.

C/N Ratio Conditions During Composting Process
Compost maturity can be seen from two things, namely qualitatively such as color, smell and texture as well as quantitatively, namely the value of the C/N ratio.The decrease in the C/N ratio occurred due to the carbonization and denitrification processes.Carbonization is the release of C-organic into the air in the form of carbon dioxide, this occurs because C-organic is used by microorganisms as an energy source so that carbon levels are reduced.While denitrification is the release of nitrogen oxides from their bonds to become free nitrogen, thereby increasing the organic N content in the compost heap.N-organic is used by microorganisms for the formation of cell structures.
In the third week of the composting process, each reactor showed a decrease, the C/N ratio was in accordance with SNI 19-7030-2004 standards, namely 19.2 in the reactor with the addition of 4 kg of filter cake and mechanical aeration using an aerator with a dose of 1.8l/min/kgVs is equivalent to 0.1 bar.However, sometimes the value of the C/N ratio at compost maturity can be relatively above 20, this is because there are some forms of C-organic which are difficult to be degraded by microorganisms.The decrease in the C/N ratio of each reactor can be seen through the C/N ratio data graph.N is shown in the pictures below:  From the graphs above, each reactor experienced a decrease in the C/N ratio on the 7th day of the composting process.This is due to reduced C-organic content from the heap and released into the air in the form of carbon dioxide, as well as increased Norganic content due to the release of nitrogen oxide bonds to become free nitrogen, thereby increasing the N-organic content in the compost heap.Data on the decrease in the C/N ratio were tested.statistics to determine the effect of differences from the two treatments applied.The statistical test used is the Two-Way ANOVA method, because there is more than one variable that is expected to affect the decrease in the C/N ratio.Through statistical tests the weight of the addition of bag cake p-value is 0.977 if the p-value is more than 0.05 then the weight of the addition of bag cake does not affect the decrease in the C/N ratio, seen from the aerator dose treatment it shows a large p-value of 0.022, if the p-value is less than 0 .05, the aerator dose has an effect on decreasing the C/N ratio.

Shredder Bacteria
In decomposing organic materials, the role of decomposing bacteria or microorganisms is very important.According to Djuarani (2004) because these microorganisms break down organic compounds into simpler compounds to produce energy.The energy produced is mostly used for the synthesis of micromolecules such as nucleic acids, lipids, and polysaccharides.Nucleic acid synthesis is important for cell growth and development (Fitri 2012).
The data obtained was tested using the Correlation method statistical test to find out whether or not there was a relationship between bacterial growth and a decrease in the C/N ratio.From the results of the Correlation statistical test, the correlation value is negative, meaning that the relationship between the 2 variables if one variable decreases, the other variable will increase.The p-value is 0.024, so there is a correlation or relationship between the two variables.In other words, the development of bacteria has a relationship or affects the speed of decomposition.

CONCLUSION
There is an effect of applying filter cake on compost quality with a C/N ratio of 19.2.The dose of blotong that speeds up the decomposition process the most is 4 kg per 3 kg of garden waste weight.The most effective aeration method in accelerating the composting process is mechanically using an aerator.There is an effect of applying filter cake as an activator on the speed of decomposition marked by the growth of bacteria in the filter cake which affects the decrease in the C/N ratio during the decomposition process.The decrease in the C/N ratio is 84%.

FigureFigureFigure
Figure 1.C/N Ratio During Manual Composting

Table 1 . Initial Characteristics of Blotong and Garden Waste
Source: Laboratory Analysis Results, 2013