CN112479758B - In-situ efficient deodorization method for livestock and poultry manure and sludge compost - Google Patents

Abstract

The invention belongs to the technical field of waste recycling and environmental pollution control in cyclic agriculture, and relates to an in-situ efficient deodorization method for livestock and poultry manure and sludge compost, which comprises the following steps: s101, preparing an odor absorbing material; s102, in-situ odor absorption; s103, in-situ nitrogen preservation and nutrient stabilization; and S104, storing phosphorus and preserving sulfur. The in-situ efficient deodorization method for the livestock and poultry manure and sludge compost, provided by the invention, can reduce the release of ammonia gas and hydrogen sulfide gas in the composting process of the livestock and poultry manure and the sludge, promote nitrogen and sulfur storage of the compost, improve the quality of the organic fertilizer, and has the characteristics of low cost, good effect, strong operability, no secondary pollution, environment beautification and large-area popularization and application.

Description

In-situ efficient deodorization method for livestock and poultry manure and sludge compost

Technical Field

The invention belongs to the technical field of waste recycling and environmental pollution control in cyclic agriculture, and relates to an in-situ efficient deodorization method for livestock and poultry manure and sludge compost.

Background

With the increasing improvement of the living standard of people and the increase of the demand of high-quality drinking water, meat, eggs and other materials, the rapid development of the large-scale livestock and poultry breeding industry and the sewage treatment industry is accelerated, so that a large amount of organic solid wastes such as livestock and poultry manure, sludge and the like are generated. Since the production of livestock and poultry feces and sludge is enormous and it is difficult to quickly consume or properly dispose of the feces and sludge in a short time, it is common to stack the feces and sludge in a random and natural manner. In the natural stacking process of the organic wastes such as messy stacking and disordered placement, the organic wastes rich in nitrogen, phosphorus and potassium and organic matters are gradually and naturally degraded and release pathogenic bacteria, ascarid eggs and the like contained by the organic wastes, a large number of mosquitoes, flies, harmful bacteria and pathogenic bacteria are bred and diseases are spread, meanwhile, a large number of malodorous gases containing ammonia and hydrogen sulfide are generated, and strong stimulation effects on respiratory systems, nervous systems, circulatory systems and endocrine systems of animals and people and even diseases are caused, for example, symptoms such as aversion, nausea and vomiting are generated in a short time, and serious diseases such as visual blurring, olfactory malfunction, endocrine disturbance, cardiovascular diseases and the like are caused in a long time. The odor pollution generated by the organic solid wastes such as the livestock and poultry manure, the sludge and the like is one of the major environmental problems facing the world, and directly influences the survival and development of livestock and poultry breeding, sewage treatment and organic fertilizer industries.

At present, organic solid wastes such as livestock and poultry manure and sludge can be treated by adopting a landfill method or a burning method so as to reduce the stacking amount of the organic solid wastes in the nature. However, the landfill method occupies a large area, and has the problems that the landfill leachate is difficult to treat, and a large amount of harmful gases such as methane, ammonia gas and hydrogen sulfide can be released for a long time in the landfill of organic wastes; the incineration method is effective for treating the organic solid wastes with lower water content, and the treatment of the organic solid wastes with high water content such as livestock and poultry manure, sludge and the like has the defects of high energy consumption, difficult waste gas treatment and the like. The composting method is considered as an economic and feasible biological treatment measure, is particularly more effective on high-moisture-content organic solid wastes such as livestock and poultry manure and sludge, has the characteristics of economy and feasibility, relatively simple operation and higher harmless degree, and can utilize nutrients such as nitrogen, phosphorus, potassium, organic matters and the like in the livestock and poultry manure and the sludge in a resource manner. The composting method is divided into an anaerobic fermentation composting technology and an aerobic fermentation composting technology, and the anaerobic fermentation composting technology has the defects of low treatment efficiency and long period, so that the conventional engineering composting mainly adopts the aerobic fermentation composting technology.

The aerobic fermentation composting technology is adopted to convert easily degradable organic wastes such as livestock manure, sludge and the like into organic fertilizers through the action of microorganisms, so that the using amount of chemical fertilizers in agricultural production can be reduced, the activity of beneficial microorganisms in soil can be exerted to the maximum extent, the supply of soil nutrient components is provided, and the cost of grain production is reduced while the soil is fertilized. In the process of preparing the organic fertilizer from easily degradable organic wastes such as livestock and poultry manure, sludge and the like by an aerobic fermentation technology, organic matters containing nitrogen and sulfur are quickly decomposed to release odor gas containing ammonia gas and hydrogen sulfide, so that the nitrogen and the sulfur of the compost are lost. During the composting process, the total nitrogen loss caused by ammonia gas volatilization accounts for about 37-75%. The release of serious odor in the composting process can cause the loss of nitrogen and sulfur nutrients, pollute the atmospheric environment, reduce the quality of compost products and increase the production cost of organic fertilizers. In order to protect the environment and control the odor release of the compost, sealed compost fermentation equipment can be adopted for production in engineering, and the odor is pumped to the tail end through a ventilation pipeline for targeted purification treatment. Later, scientists find that odor control in the composting process can be performed from the aspects of adjusting the composition of composting materials, improving the composting process and the like in the composting process, but the measures often cause the relevant process links of composting to become more complex, the requirements on professional knowledge and skills of practitioners are correspondingly increased, the problem of difficult popularization is also existed, the source diversity of the composting materials is limited, and the problems of inconsistent deodorization effect of the measures in the composting process are often caused. In order to obtain a good compost odor control effect in engineering composting practice, scientific researchers find through a large amount of engineering composting practices that the goal of reducing odor emission in the composting process can also be achieved by adopting an in-situ odor stabilization technical measure which is simple and convenient to operate, namely, a large amount of compost odor in-situ stabilization materials, such as azotobacter, biochar, calcium phosphate, alum, magnesium sulfate, ferric chloride, aluminum chloride and the like, are directly added into compost materials, so that the volatilization of ammonia in the composting process can be remarkably reduced, and the loss of nitrogen is reduced by 10-59%. But in engineering practice, the related nitrogen-fixing bacteria are difficult to prepare, high in application cost, limited by the specificity of the nitrogen-fixing bacteria, and not ideal in removing effects of hydrogen sulfide and other odors. In addition, although the related solid materials such as the biochar, the zeolite and the calcium phosphate have good absorption capacity for ammonia gas, the absorption capacity for hydrogen sulfide gas is relatively weak, the absorption performance of the biochar for the gas is usually limited by the raw material source and the pyrolysis preparation temperature, and at present, a unified standard commodity is not formed, so that the biochar is difficult to popularize and apply in engineering; for commercial calcium phosphate, the calcium phosphate often contains a large amount of heavy metals such as cadmium, arsenic and lead, and the use of the calcium phosphate in a large amount can further cause the heavy metals of organic fertilizers exceeding standards and the heavy metal pollution of farmland soil. In addition, commercial chemicals such as alum, magnesium sulfate and aluminum chloride have good absorption capacity for ammonia gas, and ferric chloride can even absorb ammonia gas and hydrogen sulfide at the same time, but the chemicals can be quickly dissolved and release accompanying ions after being mixed with compost materials, so that the conductivity of compost can be remarkably increased (the water-soluble salt content of compost products is increased, and the risk of soil salinization is caused); in order to reduce the risk of post-cutting salting, it is difficult to obtain a good odor removal effect if the amount of an additive such as alum, magnesium sulfate, or aluminum chloride used is reduced in the compost. At present, the malodorous pollution generated in the composting treatment process of organic solid wastes is still one of the major environmental problems facing the world.

Therefore, in combination with the actual requirements of the composting process in the engineering, in order to practically solve the technical problem that the deodorization effect is not ideal in the composting process, the compost deodorization material and the application technology still need to be further developed from the viewpoints of promoting the resource utilization and efficient harmless treatment of easily-degradable organic wastes such as livestock and poultry manure, sludge and the like.

Disclosure of Invention

The invention aims to provide an in-situ efficient deodorization method for livestock and poultry manure and sludge compost, and aims to solve the problems that the existing deodorization method for livestock and poultry manure and sludge compost is poor in effect and even has the risk of causing secondary pollution.

The invention provides an in-situ high-efficiency deodorization method for livestock and poultry manure and sludge compost, which comprises the following steps:

s101, mixing clinoptilolite or mordenite and a soluble iron salt solution according to the dosage ratio of 1g:0.5-1mL of the iron-fortified zeolite is mixed, continuously stirred for 1-2 hours at 70-80 ℃, added with sodium hydroxide solution with the same amount as the soluble ferric salt solution in the stirring process, kept stand, filtered, washed by filter residue, burned for 1-2 hours at 500-600 ℃, cooled to room temperature, leached to be neutral, sequentially dried and crushed to obtain the iron-fortified zeolite;

the concentration of the soluble ferric salt solution is 0.1-0.15 mol/L; the concentration of the sodium hydroxide solution is 3mol/L;

s102, adding 0.2-0.5% of sulfur powder into the compost materials according to the dry mass of the compost materials, carrying out aerobic fermentation, and adding not more than 4% of the iron-reinforced zeolite in the fermentation process;

s103, spraying dipotassium hydrogen phosphate solution with the concentration of 5-10 g/L into the fermented material in the S102, scattering 13X-type zeolite powder on the surface of a material stack, and continuing aerobic fermentation for 10-15 days;

based on the dry mass of the compost material, the total usage of the dipotassium hydrogen phosphate solution is less than or equal to 5 percent, and the total usage of the 13X type zeolite powder is less than or equal to 4 percent;

s104, adding 0.1-0.3% of calcium carbonate into the compost body 3-5 days before the aerobic fermentation is finished, based on the dry mass of the compost material, continuing to ferment until the fermentation period is finished, and collecting the fermented material.

Preferably, in S101, the addition time of the sodium hydroxide solution is less than 10min.

Preferably, the particle sizes of the clinoptilolite, the mordenite, the 13X-type zeolite, the calcium carbonate and the sulfur powder are all less than 0.15mm.

Preferably, the materials are turned over for many times in the aerobic fermentation process, and the adding amount of the iron-reinforced zeolite is 1-2%, the spraying amount of the dipotassium hydrogen phosphate solution is not more than 2%, and the spraying amount of the 13X type zeolite powder is 1-2% by dry mass of compost materials during each turning over.

Preferably, the water content of the compost material is adjusted to 50% -65% before aerobic fermentation in S102, and the carbon-nitrogen ratio is 1-35.

Preferably, the period of the whole aerobic fermentation is 28 to 40 days.

Preferably, the compost material is one or more of livestock and poultry manure, straw or dewatered sludge produced by sewage treatment plants meeting the requirements of agricultural sludge.

The invention also provides an organic fertilizer which comprises a product obtained by fermenting the fermentation material prepared by any one of the methods again.

Compared with the prior art, the invention has the beneficial effects that:

1. the prepared iron-reinforced zeolite material, sulfur powder, dipotassium hydrogen phosphate solution, 13X type zeolite powder and calcium carbonate are matched for use in sequence, and acidic substances generated in the biotransformation process of the iron-reinforced zeolite material in the composting process are utilized to absorb ammonia gas and hydrogen sulfide gas generated by fermentation of the composting material, so that stable ammonium ions and sulfate ions are formed and are retained in the composting material; the sulfur powder can be used for further supplementing and absorbing ammonia gas, hydrogen sulfide and volatile fatty acid substances, and further reducing the release of the odor of the compost to the external atmosphere of the compost body; the dipotassium hydrogen phosphate solution can promote the stabilization of ammonium ions and promote the in-situ stable storage of nitrogen-containing and phosphorus-containing nutrients; 13X type zeolite powder is added into the compost, so that the release of ammonia gas, hydrogen sulfide and volatile fatty acid substances into the external atmosphere of the pile body can be further reduced, the pH value of the pile body material is adjusted, and the in-situ storage of nitrogen and phosphorus is promoted; calcium carbonate is added into the compost, so that the aims of further promoting the fixation of sulfur and phosphorus and storing the sulfur and phosphorus in the compost can be achieved;

2. the raw materials adopted by the invention are sulfur powder, sodium hydroxide, soluble ferric salt, dipotassium hydrogen phosphate and calcium carbonate which are solid substances, are convenient to transport and store and operate, are easy to purchase and obtain in the market and have low price, and thus, the invention provides a convenient material for reducing the release of compost odor;

3. clinoptilolite, mordenite and 13X-type zeolite adopted by the invention are natural minerals of hydrous alkali or alkaline earth metal aluminosilicate, have unique pore structures, high surface activity, acid resistance and good thermal stability, have rich natural reserves, are the most common zeolite types in more than 40 natural zeolites found all over the world, and have low cost;

4. compared with the traditional aerobic composting technology, the invention has better odor removal, nitrogen storage and sulfur retention effects, has the advantages of low cost, good effect, strong operability, no secondary pollution, environment beautification, promotion of resource utilization of the livestock and poultry manure and the like, and can be popularized and applied in a large area.

Drawings

FIG. 1 is a scanning electron micrograph of mordenite and an iron-fortified zeolite;

FIG. 2 is an X-ray diffraction pattern of mordenite and an iron-fortified zeolite;

FIG. 3 is a graph showing the temperature change of each treatment group during composting;

FIG. 4 is a graph showing the pH change during composting for each treatment group;

FIG. 5 is a graph of the conductivity (EC) change during composting for each treatment group;

FIG. 6 is a graph of ammonium nitrogen concentration changes during composting for each treatment group;

FIG. 7 is a graph showing the variation of the ammonia concentration during composting for each treatment group;

FIG. 8 is a graph showing the change in hydrogen sulfide concentration during composting for each treatment group;

Detailed Description

The present invention is described in further detail below with reference to specific examples, which are provided for understanding and are not intended to limit the scope of the present invention.

Example 1

An in-situ high-efficiency deodorization method for livestock and poultry manure and sludge compost comprises the following steps:

s101, preparation of an odor absorbing material:

grinding 2-4 mm clinoptilolite purchased from Beijing Anji House science and technology Limited company into particle powder with the particle size of less than 0.15mm, mixing 100g clinoptilolite powder with 50mL of 0.1mol/L ferric chloride solution, continuously stirring for 1-2 h at 70-80 ℃, dropwise adding 100mL of 3mol/L sodium hydroxide solution under the stirring condition, and finishing adding within 10min so as to quickly form amorphous iron (hydrogen) oxide micro particles and increase the surface area;

standing for 6h after the sodium hydroxide solution is added, filtering and collecting the solid, leaching the solid for 3-4 times by using 60mL of deionized water, loading the solid into a ceramic crucible, transferring the solid into a muffle furnace, burning for 1h at 500 ℃, cooling to room temperature, and leaching by using 60mL of deionized water until the pH value of the solid is close to 7;

finally, drying the solid substance at 110-120 ℃ and grinding the solid substance until the particle size is less than 0.15mm to obtain the iron-reinforced zeolite material;

s102, odor in-situ absorption:

fully mixing the prepared compost material with sulfur powder with the particle size of less than 0.15mm, adjusting the water content of the compost mixed material to be 50% and the carbon-nitrogen ratio to be 1; meanwhile, in the fermentation process, the iron-reinforced zeolite material prepared in the step S101 is uniformly thrown on the surface of the stacked material and is turned over; wherein, the usage of the sulfur powder is 0.2 percent based on the dry mass of the compost material, the scattering amount of the iron-reinforced zeolite material is 1 percent during each pile turning, and the total usage of the iron-reinforced zeolite material in the whole process is not more than 4 percent;

in the stage, the compost is in the heating and high-temperature period of aerobic fermentation, a large amount of ammonia gas and hydrogen sulfide gas can be emitted, and meanwhile, the sulfur powder can be biologically converted to generate acid substances, so that in-situ synchronous absorption of most of the ammonia gas and the hydrogen sulfide gas generated by fermentation of the compost materials is realized, and stable ammonium ions and sulfate ions are formed and retained in the compost materials; the iron-reinforced zeolite material scattered on the surface of the compost can absorb part of ammonia gas and hydrogen sulfide gas released from the compost material and not absorbed by acidic substances; after compost is turned, the iron-reinforced zeolite material mixed into the compost material due to turning can further absorb and fix ammonium ions and sulfate ions contained in the compost material;

s103, in-situ nitrogen preservation and nutrient stabilization:

after the high-temperature period of aerobic fermentation is finished, the release speed of ammonia gas and hydrogen sulfide gas in compost materials is reduced, ammonium ions in the compost materials contain high phosphorus, then aerobic fermentation is continued for 15 days, dipotassium hydrogen phosphate solution with the concentration of 5g/L is respectively sprayed into the compost materials and fully mixed in 13 th and 20 th days of composting, the spraying amount of each time is controlled not to exceed 2% of the dry mass of the compost materials, the total using amount of the dipotassium hydrogen phosphate solution in the whole process is controlled not to exceed 5%, in-situ stabilization of the ammonium ions can be promoted, and the effect of preserving nitrogen of the compost is achieved;

meanwhile, grinding 13X type zeolite particles of 2-5 mm purchased from the Anhui Tianpu' k environmental protection adsorption material Co., ltd into powder, scattering 1-13X type zeolite powder to the surface of the pile body according to the dry mass of the compost material, and controlling the total dosage of the 13X type zeolite powder not to exceed 4% in the whole process, wherein the 13X type zeolite powder can further absorb ammonia gas, hydrogen sulfide and volatile fatty acid substances slowly released in the fermentation process of the compost material, so that the release of the ammonia gas, the hydrogen sulfide and the volatile fatty acid substances to the external atmosphere of the pile body is further reduced; after compost is turned, the 13X-type zeolite powder mixed into the compost materials due to turning can further absorb and fix ammonium ions, nitrate ions, sulfate ions, ammonia gas, hydrogen sulfide and volatile fatty acid substances in the compost materials, and plays a role in-situ nitrogen retention and nutrient stabilization in the composting process;

s104, storing phosphorus and preserving sulfur:

adding 0.1% of calcium carbonate powder into the compost body 5 days before the end of the primary fermentation period of the compost by dry mass of compost materials, wherein the particle size of the calcium carbonate powder is smaller than 0.15mm, and the calcium carbonate can fix sulfate ions through the calcium carbonate powder and realize the in-situ stabilization of the sulfate and phosphate ions; after the materials are fully mixed, continuing aerobic fermentation until the materials are finished, and transferring the obtained fermented materials into a secondary fermentation workshop to be used as a processing raw material for refining an organic fertilizer product at the later stage.

Example 2

An in-situ high-efficiency deodorization method for livestock and poultry manure and sludge compost comprises the following steps:

s101, preparation of an odor absorbing material:

grinding mordenite which is about 2mm and purchased from a Tulipa Hongshan zeolite factory into particle powder with the particle size of less than 0.15mm, mixing 100g of mordenite powder with 100mL of ferric nitrate solution with the concentration of 0.15mol/L, continuously stirring for 1-2 h at 70-80 ℃, dropwise adding 100mL of 3mol/L sodium hydroxide solution under the condition of stirring, and finishing the adding within 10min so as to quickly form amorphous iron (hydrogen) oxide micro-particles;

standing for 6h after the sodium hydroxide solution is added, filtering and collecting the solid, leaching the solid for 3-4 times by using 60mL of deionized water, loading the solid into a ceramic crucible, transferring the solid into a muffle furnace, burning for 2h at 500 ℃, cooling to room temperature, and leaching by using 60mL of deionized water until the pH value of the solid is close to 7;

finally, drying the solid substance at 110-120 ℃ and grinding the solid substance until the particle size is less than 0.15mm to obtain the iron-reinforced zeolite material;

s102, odor in-situ absorption:

fully mixing the prepared compost material with sulfur powder with the particle size of less than 0.15mm, adjusting the water content of the compost material to be 65% and the carbon-nitrogen ratio to be 1; during the period, the iron-reinforced zeolite material prepared in the step S101 is uniformly thrown on the surface of the stacked material, and the stack is turned for 3 times; wherein, the usage of the sulfur powder is 0.3 percent based on the dry mass of the compost material, the scattering amount of the iron-reinforced zeolite material is 1 percent during each pile turning, and the total usage of the iron-reinforced zeolite material in the whole process is not more than 4 percent;

at this stage, the compost is in the temperature rising and high temperature period, a large amount of ammonia gas and hydrogen sulfide gas can be emitted, and meanwhile, sulfur powder can be biologically converted to generate acid substances, so that in-situ synchronous absorption of most of the ammonia gas and the hydrogen sulfide gas generated by fermentation of the compost material is realized, and relatively stable ammonium ions and sulfate ions are formed and are retained in the compost material; the iron-reinforced zeolite material scattered on the surface of the compost can absorb part of ammonia gas and hydrogen sulfide gas released from the compost material and not absorbed by acidic substances; after compost is turned, the iron-reinforced zeolite material mixed into the compost material due to turning can further absorb and fix ammonium ions and sulfate ions contained in the compost material;

s103, in-situ nitrogen preservation and nutrient stabilization:

after the high-temperature period of aerobic fermentation is finished, the compost is gradually and naturally cooled, the release speed of ammonia and hydrogen sulfide gas in the compost material is reduced, the phosphorus content of ammonium ions in the compost material is higher, and then dipotassium hydrogen phosphate solution with the concentration of 10g/L is sprayed into the compost material and fully mixed respectively at 20 th and 30 th days of composting, the spraying amount is controlled not to exceed 2% of the dry mass of the compost material, the total using amount of the dipotassium hydrogen phosphate solution in the whole process is controlled not to exceed 5%, the in-situ stabilization of the ammonium ions can be promoted, the nitrogen retention effect of the compost is achieved, and the aerobic fermentation is continued for about 1 week;

meanwhile, grinding 2-5 mm small 13X type zeolite particles purchased from Angiopoks, anhui, china, inc. of environmental protection adsorbing materials into powder, scattering 2-13X type zeolite powder to the surface of the pile body according to the dry mass of the compost materials, and controlling the total using amount of the 13X type zeolite powder not to exceed 4% in the whole process, wherein the 13X type zeolite powder can further absorb ammonia, hydrogen sulfide and volatile fatty acid substances slowly released in the fermentation process of the compost materials, so that the release of the ammonia, the hydrogen sulfide and the volatile fatty acid substances into the external atmosphere of the pile body is further reduced; after compost is turned, the 13X type zeolite powder mixed into the compost materials due to turning can further absorb and fix ammonium ions, nitrate ions, sulfate ions, ammonia gas, hydrogen sulfide and volatile fatty acid substances in the compost materials, and plays roles of in-situ nitrogen preservation and nutrient stabilization in the composting process;

s104, storing phosphorus and preserving sulfur:

3 days before the end of the primary fermentation period of the compost, adding 0.2 percent of calcium carbonate powder into the compost body by the dry mass of the compost material, and enabling the particle size of the calcium carbonate powder to be less than 0.15mm, wherein the calcium carbonate can realize the in-situ stabilization of sulfate radicals and phosphate radical ions through the fixation effect of the calcium carbonate on the sulfate radical ions; and (3) after the materials are fully and uniformly mixed, continuing aerobic fermentation until the end, and transferring the obtained materials into a secondary fermentation workshop to be used as a processing raw material for refining an organic fertilizer product in the later period.

Example 3

An in-situ high-efficiency deodorization method for livestock and poultry manure and sludge compost comprises the following steps:

s101, preparing an odor absorbing material:

grinding mordenite which is about 2mm and purchased from a Tulipa Hongshan zeolite factory into particle powder with the particle size of less than 0.15mm, mixing 100g of the mordenite powder with 100mL of ferrous sulfate solution with the concentration of 0.15mol/L, continuously stirring for 1-2 h at 70-80 ℃, dropwise adding 100mL of 3mol/L sodium hydroxide solution under the condition of stirring, and finishing the adding within 10min so as to quickly form amorphous iron (hydrogen) oxide micro-particles;

standing for 6 hours after the sodium hydroxide solution is added, filtering and collecting solids, leaching the solids for 3-4 times by using 60mL of deionized water, loading the solids into a ceramic crucible, transferring the ceramic crucible into a muffle furnace, burning for 1 hour at 600 ℃, cooling to room temperature, and leaching by using 60mL of deionized water until the pH of the solid matter is close to 7;

finally, drying the solid substance at 110-120 ℃ and grinding the solid substance until the particle size is less than 0.15mm to obtain the iron-reinforced zeolite material;

s102, odor in-situ absorption:

fully mixing the prepared compost material with sulfur powder with the particle size of less than 0.15mm, adjusting the water content of the compost mixed material to be 55% and the carbon-nitrogen ratio to be 1; during the period, the compost is manually turned over for 1 time on the 3 rd, 6 th and 9 th days, and simultaneously the iron-reinforced zeolite material prepared by the S101 is uniformly thrown on the surface of the compost material in the aerobic fermentation process and turned over for 3 times in the period;

wherein, the usage of the sulfur powder is controlled to be 0.5 percent based on the dry mass of the compost material, the scattering amount of the iron-reinforced zeolite material is 1 percent during each pile turning, and the total usage of the iron-reinforced zeolite material in the whole process is not more than 4 percent;

at this stage, the compost is in the temperature rising and high temperature period, a large amount of ammonia gas and hydrogen sulfide gas can be emitted, and meanwhile, sulfur powder can be biologically converted to generate acid substances, so that in-situ synchronous absorption of most of the ammonia gas and the hydrogen sulfide gas generated by fermentation of the compost material is realized, and relatively stable ammonium ions and sulfate ions are formed and are retained in the compost material; the iron-reinforced zeolite material scattered on the surface of the compost can absorb part of ammonia gas and hydrogen sulfide gas released from the compost material and not absorbed by acidic substances; after compost is turned, the iron-reinforced zeolite materials mixed into the compost materials due to turning can further absorb and fix ammonium ions and sulfate ions contained in the compost materials;

s103, in-situ nitrogen preservation and nutrient stabilization; after the aerobic fermentation high-temperature period is finished, gradually and naturally cooling, the release speed of ammonia gas and hydrogen sulfide gas in compost materials is reduced, the phosphorus content of ammonium ions in the compost materials is higher, at the moment, manual turning is carried out for 1 time in 12 th and 21 th days of the compost respectively, dipotassium hydrogen phosphate solution with the concentration of 8g/L is sprayed into the compost materials and fully mixed, the total using amount of the dipotassium hydrogen phosphate solution in the whole process is controlled not to exceed 5%, the in-situ stabilization of the ammonium ions can be promoted, the nitrogen retention effect of the compost is achieved, and the aerobic fermentation is continued for about 10 days;

meanwhile, grinding 2-5 mm small 13X type zeolite particles purchased from environmental protection adsorbing material Limited of Anguiliki into powder, and scattering 2%13X type zeolite powder to the surface of the pile body according to the dry mass of the compost material, and controlling the total consumption of the 13X type zeolite powder not to exceed 4% in the whole process, wherein the 13X type zeolite powder can further absorb ammonia gas, hydrogen sulfide and volatile fatty acid substances slowly released in the fermentation process of the compost material, and further reduce the release of the ammonia gas, hydrogen sulfide and volatile fatty acid substances to the outside atmosphere of the pile body; after compost is turned, the 13X type zeolite powder mixed into the compost materials due to turning can further absorb and fix ammonium ions, nitrate ions, sulfate ions, ammonia gas, hydrogen sulfide and volatile fatty acid substances in the compost materials, and plays roles of in-situ nitrogen preservation and nutrient stabilization in the composting process;

s104, storing phosphorus and preserving sulfur;

3 days before the end of the primary fermentation period of the compost, adding 0.3 percent of calcium carbonate powder into the compost body by the dry mass of the compost material, and enabling the particle size of the calcium carbonate powder to be less than 0.15mm, wherein the calcium carbonate can realize the in-situ stabilization of sulfate radicals and phosphate radical ions through the fixation effect of the calcium carbonate on the sulfate radical ions; and (3) after the materials are fully and uniformly mixed, continuing aerobic fermentation until the end, and transferring the obtained materials into a secondary fermentation workshop to be used as a processing raw material for refining an organic fertilizer product in the later period.

Since the application effects obtained in the strip pile compost and the open fermentation tank compost in examples 1, 2 and 3 are substantially the same, the in-situ high-efficiency deodorizing effect on the livestock manure and sludge compost will be described below by taking only the semi-open fermentation tank compost of example 3 as an example.

The experimental study is carried out in a certain livestock breeding station of Yangling in Shaanxi province, wherein the livestock breeding station has 2000 livestock stocks of piglets, 100 livestock stocks of boars and sows, 500 livestock stocks of meat goats, 500 milk goats, 200 beef cattle and 100 dairy cows. In the test, 1 ton of excrement of different livestock and poultry is respectively collected, 1 ton of dewatered sludge of a certain sewage treatment plant of Yangling in Shaanxi province, 1 ton of straw mixture of straw feed residues and waste straws of a farm are collected simultaneously, and the aerobic composting test for 35 days is carried out in a semi-open fermentation tank mode. When composting is carried out, mixing the livestock and poultry manure, sludge and straw mixture according to the dry mass ratio of 1; fully and uniformly mixing the materials, and ensuring that the particle size of the mixed material particles is less than 1cm; then the mixed materials are put into a semi-open fermentation tank and covered tightly by plastic paper, the contrast treatment and the treatment of adding medicament are also set, the total number is 6 treatments, 1 of the 6 treatments is used as a contrast treatment group (without adding any medicament), the rest is added with 0.5% of sulfur powder, 0.5% of sulfur powder and 4% of iron reinforced zeolite, 4% of 13X type zeolite, 5% of dipotassium hydrogen phosphate solution and 0.3% of calcium carbonate, and the treatment groups are respectively marked as comparison treatment, 0.5S, 0.5S +4F +4X +5P and 0.5S +4F +4X +4 + 3P +0.3% of calcium carbonate.

The iron-reinforced zeolite is prepared by the following specific steps: firstly, grinding mordenite into particle powder with the particle size of less than 0.15mm, then mixing 100g of mordenite powder with 100mL of ferrous sulfate solution with the concentration of 0.15mol/L, continuously stirring for 1.5h at 70-80 ℃, dropwise adding 100mL of 3mol/L sodium hydroxide solution under the stirring condition, and finishing the adding within 10 min; and standing for 6 hours after the sodium hydroxide solution is added, filtering and collecting the solid, leaching the solid with 60mL of deionized water for 4 times, putting the solid into a ceramic crucible, transferring the ceramic crucible into a muffle furnace, burning for 1 hour at 500 ℃, cooling to room temperature, and leaching with 60mL of deionized water until the pH of the solid is close to 7. Scanning Electron Microscope (SEM) pictures and powder X-ray diffraction patterns (XRD) of the common mordenite and the iron-reinforced zeolite material are respectively shown in figure 1 and figure 2. Compared with the common mordenite, the prepared iron-reinforced zeolite material is rich in a pore structure, the pores and the surfaces of the material are covered with a large amount of amorphous iron oxide particles, and the odor absorption effect of the material is obviously better than that of the common mordenite.

In the test, the temperature of the surface layer 30cm around the stack and the temperature of the center 60cm around the stack were measured by a Beckman thermometer every day and averaged, and the temperature change of the stack was recorded. Meanwhile, the compost is manually turned 1 time on 3 rd, 6 th, 9 th, 12 th, 21 th and 32 th days respectively, and the compost is tightly covered by plastic paper after being turned. Wherein, when turning over the pile on days 1, 6, 12 and 32, immediately monitoring the concentration of ammonia gas and hydrogen sulfide, simultaneously collecting 4 kg of each compost sample, putting the compost sample in a plastic barrel and bringing the compost sample back to a laboratory for measuring the concentration of pH, EC and ammonium nitrogen. When the one-time fermentation composting is finished in 35 days, monitoring indexes such as total nitrogen, total phosphorus, available phosphorus, total sulfur, sulfate radicals, potherb mustard seed germination indexes and the like in a compost product; the pH and conductivity (EC) (solid-to-liquid ratio 1.

The results are shown in FIGS. 3-8.

As can be seen from FIGS. 3-8, compared with the control treatment group, by using the livestock manure and sludge composting in-situ deodorization method (0.5S +4F +4X +5P +0.3C treatment) provided by the invention, the high-temperature harmless treatment of the compost in the aerobic stacking process is not obviously affected, and the high-temperature harmless requirement of the compost and the biomineralization degradation of organic materials can be ensured; meanwhile, the method provided by the invention (0.5S +4F +4X +5P +0.3C treatment) can effectively promote the ammonia gas to be converted into ammonium nitrogen, effectively reduce the concentration of ammonia gas and hydrogen sulfide odor discharged by composting, and compared with a control treatment group, the concentration of ammonia gas and hydrogen sulfide in the composting process is respectively reduced by 95.8% and 77.6%, and the risk of atmospheric pollution caused by the release of odor in the composting process can be greatly reduced.

The results of measuring the relevant indices in the compost products 35 days after the compost treatment in each treatment group are shown in Table 1.

TABLE 1 determination of the relevant indices in the compost products after 35 days of treatment in each treatment group

As can be seen from Table 1, the total nitrogen content in the compost products treated by the control and treated by 0.5S +4F +4X +5P +0.3C is 18.67 and 22.68g/kg respectively, the total sulfur content is 3.83 and 8.71g/kg respectively, the water-soluble sulfate radical content is 0.69 and 0.06g/kg respectively, the total phosphorus content is 17.13 and 19.26g/kg respectively, the effective phosphorus content is 42.7 percent of the total phosphorus and the treatment content is 3.12 percent, and the method provided by the invention can effectively promote the nitrogen retention of the compost and realize the slow release of the phosphorus and the sulfur nutrients.

In order to ensure the farmland safe use of the compost products, the compost products are further subjected to a phytotoxicity test. The results show that indices of germination of potherb mustard seeds treated with control and treated with 0.5S +4F +4X +5P +0.3C are 1.08 and 0.93, respectively, and meet the national Standard for organic fertilizers (NY 525-2012).

The results show that the method provided by the invention can effectively reduce the emission of ammonia gas and hydrogen sulfide odor in composting, has good effects of nitrogen preservation in composting, sulfur storage and phosphorus fixation, can improve the quality of composting products, beautifies the environment, reduces pollution, and promotes the resource utilization of livestock and poultry manure and sludge.

It should be noted that the steps and methods adopted in the claims of the present invention are the same as those of the above-mentioned embodiments, and for the sake of avoiding redundancy, the present invention describes the preferred embodiments, but those skilled in the art can make other changes and modifications to these embodiments once they learn the basic inventive concept. Therefore, it is intended that the appended claims be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (7)

1. An in-situ efficient deodorization method for livestock and poultry manure and sludge compost is characterized by comprising the following steps:

s101, mixing clinoptilolite or mordenite and a soluble iron salt solution according to the dosage ratio of 1g:0.5-1mL of the iron-fortified zeolite is mixed, continuously stirred for 1-2 hours at 70-80 ℃, added with sodium hydroxide solution with the same amount as the soluble ferric salt solution in the stirring process, kept stand, filtered, washed by filter residue, burned for 1-2 hours at 500-600 ℃, cooled to room temperature, leached to be neutral, sequentially dried and crushed to obtain the iron-fortified zeolite;

the concentration of the soluble ferric salt solution is 0.1-0.15 mol/L; the concentration of the sodium hydroxide solution is 3mol/L;

s102, adding 0.2-0.5% of sulfur powder into the compost materials according to the dry mass of the compost materials, carrying out aerobic fermentation, and adding not more than 4% of the iron-reinforced zeolite in the fermentation process;

s103, spraying dipotassium hydrogen phosphate solution with the concentration of 5-10 g/L into the material fermented in the S102, scattering 13X-type zeolite powder on the surface of a material pile, and continuing aerobic fermentation for 10-15 days;

the total dosage of the dipotassium phosphate solution is less than or equal to 5 percent and the total dosage of the 13X type zeolite powder is less than or equal to 4 percent based on the dry mass of the compost material;

s104, adding 0.1-0.3% of calcium carbonate into the compost body 3-5 days before the aerobic fermentation is finished, continuing to ferment until the fermentation period is finished, and collecting the obtained fermented material;

the method comprises the steps of turning materials for multiple times in an aerobic fermentation process, wherein the adding amount of the iron-reinforced zeolite is 1-2%, the spraying amount of a dipotassium hydrogen phosphate solution is not more than 2%, and the spraying amount of 13X-type zeolite powder is 1-2% based on the dry mass of compost materials during each turning.

2. The method for in situ highly effective deodorization of compost of livestock and poultry manure and sludge as claimed in claim 1, wherein in S101, the addition time of said sodium hydroxide solution is less than 10min.

3. The method for in-situ efficient deodorization of compost of livestock and poultry manure and sludge as claimed in claim 1, wherein the particle sizes of clinoptilolite, mordenite, zeolite 13X, calcium carbonate and sulfur powder are all less than 0.15mm.

4. The in-situ efficient deodorization method for compost of livestock and poultry manure and sludge as claimed in claim 1, characterized in that in S102, the water content of the compost material is adjusted to 50% -65% and the carbon-nitrogen ratio is adjusted to 1-35.

5. The method for efficiently deodorizing livestock manure and sludge compost in situ according to claim 1, wherein the period of the whole aerobic fermentation is 28 to 40 days.

6. The method for in-situ efficient deodorization of livestock manure and sludge compost as claimed in claim 1, wherein said compost material is one or more of mixture of livestock manure, straw or dewatered sludge produced by sewage treatment plants satisfying agricultural sludge requirements.

7. An organic fertilizer, characterized in that it comprises a product obtained by re-fermenting the fermented material obtained by the method of any one of claims 1 to 6.

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