CN107573111A - A kind of method that organic domestic waste is handled using zymophyte aerobic compost - Google Patents

Abstract

The invention discloses a method for treating organic household garbage by aerobic composting with fermentation bacteria. The method comprises: preprocessing the household garbage through steps such as sorting, crushing, squeezing, and dehydration; mixing and composting the garbage and fermentation bacteria Finally, after turning over for 3 days, continue to ferment until the garbage is mature; the mature garbage is sieved through the sieve; the garbage that passes the sieve is mixed evenly with the fresh garbage and fermentation bacteria in a certain proportion, and enters the secondary fermentation stage; so cycle until The amount of garbage reaches a constant level. The invention can compost the organic domestic garbage by one or more kinds of fermenting bacteria, realizes the reduction and treatment of the domestic garbage and the resource utilization at the same time, and has strong application value for the reduction and resource recovery of the organic domestic garbage.

Description

A method for treating organic domestic waste by using fermentation bacteria aerobic composting

technical field

The invention relates to a method for treating domestic garbage, in particular to a method for treating organic domestic garbage with aerobic composting by fermenting bacteria.

Background technique

Household garbage, as the name suggests, refers to solid waste generated in daily life or activities that provide services for daily life and solid waste that is regarded as domestic garbage according to laws and administrative regulations. According to different treatment methods, urban waste in my country is divided into organic waste, inorganic waste, hazardous waste and bulky waste. With the development of my country's social economy and the improvement of people's living standards, the content of organic components in municipal solid waste is high. Once domestic waste is not properly disposed of, it is very easy to emit stench, spread germs, occupy land, and affect ecological security. The reduction and harmless treatment of domestic waste has become a difficult problem to solve the problem of domestic waste.

At present, there are generally the following methods for domestic and foreign domestic waste disposal: one is sanitary landfill, which has a wide range of applications, no secondary pollution, relatively mature technology, simple operation and management, large processing capacity, and low investment and operating costs. , but at the same time there are problems such as low level of resource utilization, large amount of space resources occupied by mixed waste, and high cost of leachate treatment. The second is the incineration method. This method has a fast processing speed and good volume reduction. It can also use the recovered heat to produce steam and generate electricity. However, this method has high costs and will produce harmful substances that cause secondary pollution during the incineration process. The third is composting. This method has simple process, less mechanical equipment, less investment, simple operation and low operating cost. However, the quality of traditional composting is not high, and the smell and sewage have a greater impact on the surrounding environment. The content of organic matter in domestic waste is high, and aerobic composting by fermentation bacteria can make organic domestic waste harmless and resourceful. At the same time, this method is also a manifestation of recycling beneficial substances in response to the call of the national conservation-oriented society; It is an effective treatment method for the harmlessness, reduction and resource utilization of domestic waste.

Contents of the invention

In order to overcome the above-mentioned defects of the prior art, the present invention proposes a method for treating organic domestic garbage by aerobic composting with fermentation bacteria. The invention adopts the process of pretreatment, mixing fermentation bacteria and organic waste to carry out aerobic composting, composting maturity, secondary composting, tertiary composting and the like. The invention utilizes fermenting bacteria to ferment and degrade garbage, so as to realize the reduction and resource treatment of household garbage, and turn waste into treasure.

The technical scheme that the present invention takes is as follows:

A method for treating organic domestic waste by fermenting bacteria aerobic composting, comprising the following steps:

(a) pretreatment, including sorting, crushing, pressing, dehydration steps;

(b) Transport the pretreated garbage to the aerobic compost bin, mix the fermentation bacteria and the garbage at a certain mass ratio, perform aerobic composting, monitor the temperature of the compost core, and turn the compost at the 3rd to 6th day; When the aerobic composting reaches the 6th-9th day, the composted mature garbage is obtained;

(c) sieve the mature garbage in step (b) by using a sieve, landfill the garbage that does not pass through the sieve, and use the garbage that passes the sieve for secondary composting;

(d) Entering the secondary composting stage, the fresh domestic waste is pretreated according to step (a) and then transported to the compost bin, and at the same time, the composted mature waste passed through the screen in the above step (c) is mixed with fresh domestic waste and transported to In the compost bin, add fermentation bacteria, mix well, and carry out secondary composting, continue to monitor the temperature online in real time, and regularly monitor the core temperature every day, until the 3rd to 6th day, turn the compost; compost to the 6th to 9th day, the compost is mature (when the number of days of fermentation before turning over is the 6th day, the number of days of fermentation after turning over is the 7th-9th day).

Use the same operation method to enter three composting stages, four composting stages, ... to achieve the purpose of reduction and product availability.

In step (a), a dehydrator is used to sort, crush, squeeze and dehydrate the garbage transported by the domestic garbage transport vehicle, and then transfer the garbage to a compost bin.

In step (a), the sorting refers to sorting non-compostable materials such as plastic, glass and metal blocks in domestic waste to ensure the subsequent composting process.

In step (a), the crushing refers to crushing the sorted compostable garbage, and the particle size after crushing is 1-10 cm, preferably 3-5 cm.

In step (a), the squeezing refers to using a squeezer (such as a kitchen waste squeezer) to squeeze the crushed compostable garbage, so that the leachate contained in the compostable garbage is squeezed and flows out from the sieve, Discharged from the drain.

In step (a), the dehydration refers to controlling the slag discharge resistance and the size of the slag outlet of the squeezer (such as a kitchen waste squeezer), and adjusting the degree of dryness and wetness of the dehydration. After dehydration, the moisture content of the compostable garbage is 70-85% %.

In step (b), the fermenting bacteria are composted by using agricultural waste and adding auxiliary materials, and mainly involve fungi and actinomycetes. Agricultural wastes can be selected from corn stalks, rice straws, wheat straws, and sugar beet pulp. The auxiliary materials added are composed of urea, amino acids, and rice husks. After the agricultural wastes are mixed with the auxiliary materials, the C/N is controlled at 25-30:1. The moisture content is controlled at 55-65%.

The fermenting bacteria in the present invention can also be one or more of additionally added bacteria, yeasts, fungi and actinomycetes. The bacteria include Bacillus and the like. The mass ratio of the fermentation bacteria to the garbage is (0.1-0.4):1; preferably, it is (0.1-0.2):1.

In step (b), a mixer truck is used to mix the fermentation bacteria and garbage evenly.

In step (b), the temperature of the compost is kept at 60-70° C., and the moisture content is kept at 40-50%.

In step (b), the time for composting is preferably 6 days.

In step (b), proper amount of aeration is performed every day, and the aeration time is continuously maintained for at least 2 hours (preferably 4 hours) every day, and the aeration volume is controlled at 0.2-0.5m ³ /min·m ³ to ensure normal aerobic composting.

In step (b), the temperature of the core is monitored to keep the temperature of the core at 60-70° C. If the temperature is too high or too low, it is not conducive to microbial fermentation. When the temperature is too high, it is necessary to turn the compost to lower the temperature below 70°C to avoid adverse effects on the composting microorganisms; Moisture content and temperature are maintained at 40-50% and 60-70°C respectively.

In step (d), the composted mature garbage is used as the starter of garbage composting in the secondary composting stage to realize resource recycling.

In step (d), when entering the secondary composting stage, the mass ratio of fresh garbage, composted mature garbage, and fermentation bacteria is 100-110:100-120:2-3; preferably, it is 100:100:2. That is, preferably according to the amount of fresh garbage after pretreatment+the amount of composted mature garbage equal to the amount of fresh garbage after pretreatment+2% (accounting for the amount of fresh garbage after pretreatment) fermenting bacteria as the proportion of continuing composting in the later stage , Use a mixer truck to mix the fermentation bacteria and garbage. Other conditions are the same as those of the first composting.

Among them, the water content and temperature of the method of the present invention are very critical process parameters, and only when these two parameters are within the above-mentioned appropriate ranges can the expected effect of the present invention be achieved.

The traditional composting method is to use the indigenous microorganisms in the composting raw materials to degrade organic pollutants by increasing nutrients and improving environmental conditions. Therefore, traditional compost often has problems such as long fermentation time and incomplete degradation. However, the present invention uses fermenting bacteria for aerobic composting, which can increase the total amount of high-efficiency microorganisms in the initial domestic garbage pile, accelerate the composting of composting materials, and reduce composting time. In addition, the aerobic compost of the present invention has a high temperature, and has a good effect on eliminating certain pathogens, insect eggs and weed seeds, etc., and can increase beneficial microorganisms in the finished compost, and the degradation is relatively thorough. Aerobic composting of organic domestic waste by fermenting bacteria is a widely concerned composting technology in the field of solid waste treatment, and it is also an effective method.

The present invention uses "fermentation bacteria for the treatment of domestic waste" by directly mixing the fermentation bacteria with the pretreated compostable domestic waste in proportion. The operation is simple and convenient, and no activation or pre-cultivation of the fermentation bacteria is required. Pre-preparation, the fermented bacteria after composting can be recycled, the composting process requires less oxygen, and the aeration time is flexible. The fermenting bacteria include one or more of bacteria, yeast, fungi and actinomycetes. The bacteria include Bacillus and the like. The mass ratio of the fermentation bacteria to the garbage is (0.1-0.4):1.

Since domestic waste contains a large amount of organic matter, organic matter is a food source for biological bacteria. The fermentation bacteria used in the method of the present invention can be to utilize microorganisms such as bacteria, saccharomycetes, fungus and actinomycetes that exist in domestic waste, simultaneously by adding high-efficiency fermentation strains such as bacillus (the quality of described fermentation bacteria and garbage The ratio is (0.1-0.4):1), which accelerates the biochemical reaction of organic matter in garbage to degrade and form relatively stable organic matter such as humic acid, amino acid and low-molecular-weight organic matter. The principle is shown in Figure 1.

The invention has the effects of less investment in composting, less energy consumption for treatment, low treatment cost, short composting time, simple equipment, no pollutants in the treatment process, and environmental friendliness. The invention utilizes fermented bacteria aerobic composting to degrade and transform domestic waste, realizes domestic waste reduction and resource treatment, waste composting takes less time, composts in only 6 days, the amount of waste can be reduced by 60%, and the composting products can be used for greening and soil improvement, to realize the recycling of waste. The present invention needs to further clarify the two important parameters of moisture content and temperature. If these two parameters are changed, the effects described in the present invention will not be realized.

Description of drawings

Fig. 1 is a schematic diagram of aerobic composting treatment of organic domestic waste by fermenting bacteria of the present invention.

Fig. 2 is a process flow diagram of the aerobic composting process of organic domestic waste by fermenting bacteria of the present invention.

Fig. 3 is the on-site composting figure of step b' of Example 1 of the present invention; wherein, the left picture is the picture when the on-site composting reaches the 3rd day, and the right picture is the picture when the on-site composting reaches the 6th day when the composting matures.

Fig. 4 is a graph showing the change in temperature of the on-site compost core with time in step b' of Example 1 of the present invention.

detailed description

The present invention will be further described in detail in conjunction with the following specific embodiments and accompanying drawings. The process, conditions, experimental methods, etc. for implementing the present invention, except for the content specifically mentioned below, are common knowledge and common knowledge in this field, and the present invention has no special limitation content.

The detailed technological process of fermenting bacterium aerobic composting method for processing organic domestic waste of the present invention is:

Example 1

(a') Sorting non-compostable materials such as plastic, glass and metal blocks in the domestic waste collected by the domestic waste transport vehicle, and transporting the sorted compostable waste to the crusher for crushing, and the crushed waste The particle size is 3-5cm. The food waste squeezer is used to squeeze the crushed compostable garbage, so that the leachate contained in the compostable garbage is squeezed and flows out from the sieve hole, and is discharged from the water collection pipe to control the slag discharge resistance of the squeezer and the slag outlet. Size, adjust the dryness and wetness of dehydration, the moisture content of compostable garbage after dehydration is 70-85%. The dehydrated compostable garbage is transported to the compost bin by the excavator.

(b') Transport the pretreated garbage to the compost bin, and use a mixer truck to mix the fermented bacteria and garbage composted from agricultural waste with auxiliary materials at a ratio (mass ratio) of 0.2:1 for aerobic composting , the daily ventilation time is maintained continuously for 4 hours, and the ventilation volume is controlled at 0.2-0.5m ³ /min.m ³ to ensure the normal progress of aerobic composting. Insert a real-time online monitoring thermometer into the core to monitor the core temperature and keep the core temperature at 60-70°C. If the temperature is too high or too low, it is not conducive to microbial fermentation. When the temperature is too high, it is necessary to turn the compost to lower the temperature below 70°C to avoid adverse effects on the composting microorganisms; Moisture content and temperature are maintained at 40-50% and 60-70°C respectively. The aerobic composting is turned on the 3rd day; when the aerobic composting is on the 6th day, composted mature garbage is obtained.

(c') Transport the composted mature garbage to the screen of the vibration separator, transport the garbage that does not pass the screen to the landfill, and transport the garbage that passes the screen to the secondary composting stage.

(d') Entering the secondary composting stage, the fresh garbage from the domestic garbage transport vehicle is pretreated according to step (a') and then transported to the composting bin, and at the same time, the mature composted garbage in step (c') is transported to the fermentation bin According to the amount of fresh garbage after pretreatment+the amount of composted mature garbage equal to the amount of fresh garbage after pretreatment+2% (accounting for the weight percent of fresh garbage after pretreatment) fermenting bacteria as the compound for continuing secondary fermentation Ratio, add fermentation bacteria, use the mixer to mix it, other conditions are the same as the parameters of the first composting conditions. Continue to monitor the temperature online in real time, and regularly monitor the core temperature every day, until the third day to turn the compost; when the compost reaches the sixth day, the compost is mature. In Example 1, composting was specifically performed twice.

Among them, the reduction data of organic domestic waste treated by fermentation bacteria aerobic composting are shown in Table 1.

Table 1 The data before and after the resourceful treatment of organic domestic waste by fermentation bacteria aerobic composting

It can be seen from Table 1 that the monitoring indicators before and after the recycling of organic domestic waste by fermenting bacteria aerobic composting mainly include moisture, organic carbon, organic matter, total nitrogen, available phosphorus, and low-temperature fermentation bacteria. Through the analysis of the monitoring data, it was found that the water content of the waste after adding fermentation bacteria to compost was lower than that of the original waste, but the amount of organic carbon, organic matter, total nitrogen, available phosphorus, and low-temperature fermentation bacteria were significantly increased compared with the original waste. The method for treating organic domestic garbage by aerobic composting with fermenting bacteria can increase the total amount of high-efficiency microorganisms in the initial domestic garbage pile, accelerate the decomposition of compost materials, and increase the beneficial microorganisms in the finished compost.

To sum up, the method of the present invention not only realizes the reduction treatment of domestic garbage, but also recycles the degraded garbage, which has practical value.

The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, changes and advantages conceivable by those skilled in the art are all included in the present invention, and the appended claims are the protection scope.

Claims (11)

1. a method utilizing fermentation bacteria aerobic composting to process organic domestic waste, is characterized in that, described method comprises the following steps: (a) pretreatment, including sorting, crushing, pressing and dehydration steps; (b) In the compost bin, mix the fermented bacteria with the pretreated garbage to perform aerobic composting; monitor the core temperature, and turn the compost when the aerobic composting reaches the 3rd-6th day; aerobic composting reaches the 6th-9th day When the day comes, get the compost-ripe litter. 2. The method according to claim 1, characterized in that, the mature garbage of compost can continue to be processed through the following steps: (c) screen the mature garbage in step (b) of claim 1 by using a screen, landfill the garbage that does not pass through the screen, and use the garbage that passes through the screen for secondary composting; (d) Entering the secondary composting stage, the fresh domestic waste is pretreated according to step (a) and then transported to the compost bin, and at the same time, the composted mature waste passed through the screen in the above step (c) is mixed with fresh domestic waste and transported to In the compost bin, add fermentation bacteria, mix well, and carry out secondary composting, continue to monitor the temperature online in real time, and regularly monitor the temperature of the core every day, until the 3rd day, turn the compost; compost to the 6th-9th day, get composted mature garbage ; Enter the follow-up composting stage with the same operation method. 3. The method according to claim 1, characterized in that in step (a), the crushing refers to crushing the sorted compostable garbage, and the particle size after crushing is 1-10cm. 4. The method according to claim 1, characterized in that, in step (a), the moisture content of the dehydrated garbage is 70-85%. 5. The method according to claim 1, characterized in that, in step (b), the fermenting bacteria include one or more of bacteria, yeast, fungi and actinomycetes. 6. The method according to claim 1, characterized in that, in step (b), the mass ratio of fermentation bacteria and garbage is (0.1-0.4):1. 7. The method according to claim 1, characterized in that, in step (b), the temperature of the compost is kept at 60-70° C., and the moisture content is kept at 40-50%. 8. The method according to claim 1, characterized in that, in step (b), the time of the composting is 6 days. 9. The method according to claim 1, characterized in that, in step (b), the daily ventilation time is continuously maintained for at least 2 hours, and the ventilation volume is controlled at 0.2-0.5m ³ /min·m ³ . 10. The method according to claim 2, characterized in that, in step (d), the mature garbage of composting is used as the starter of the secondary composting stage garbage composting. 11. method according to claim 2, is characterized in that, in step (d), when entering secondary composting stage, the mass ratio of fresh rubbish, the mature rubbish of composting, fermentation bacteria is 100-110:100-120: 2-3.