Composting materials guide: What you can and cannot compost!

The core of composting is the microbial decomposition of organic materials. Material selection directly determines composting efficiency, product quality, and whether unpleasant odors are produced. The key selection criteria are “easy decomposition, harmlessness, and suitable carbon-to-nitrogen ratio.” Below is a clear list of materials that can and cannot be composted.

Compostable materials mainly consist of natural organic waste, divided into two categories: carbon-rich materials (straw, sawdust, fallen leaves) to supplement carbon elements and increase aeration; and nitrogen-rich materials (livestock manure, kitchen waste, fruit and vegetable scraps, mushroom residue) to provide nutrients and accelerate decomposition. A small amount of wood ash or composting inoculant can be added. Using an organic fertilizer composting machine for turning and mixing will improve the process. Windrow compost turning machines are suitable for large areas and heavy materials, while large wheel compost turning machines are suitable for small and medium-sized operations, helping to ensure even mixing of materials.

The following materials should absolutely not be composted: high-salt and high-fat foods (leftovers, fried foods, pickled foods), which will attract pests, produce foul odors, and inhibit microbial activity; and toxic and harmful materials (plastics, glass, straw with pesticide residues, chemical waste), which cannot be decomposed and will pollute the soil.

In addition, meat and bones decompose slowly and easily breed bacteria, so they are not recommended; large, hard objects that have not been crushed need to be crushed beforehand. After adding them, they can be turned and mixed using an organic fertilizer composting machine (both windrow and large wheel composting machines are suitable) to reduce ventilation obstruction; hazardous waste such as batteries is strictly prohibited to prevent heavy metal contamination.

In summary: Prioritize natural, easily decomposable organic waste, combine materials according to the carbon-to-nitrogen ratio, avoid prohibited materials, and use appropriate composting equipment to quickly produce high-quality, odor-free compost, contributing to soil improvement and crop growth.

Guidelines for large-scale production of bio-organic fertilizer: Key to high-efficiency mass production

The core of large-scale bio-organic fertilizer production is achieving “resource utilization of raw materials, standardized processes, mechanized equipment, and controllable quality.” This requires relying on complete sets of equipment and scientific processes, balancing mass production efficiency and fertilizer activity. The core processes and key points are as follows:

Step 1: Raw Material Pre-treatment and Proportioning: Collect livestock and poultry manure, crop straw, and other raw materials in batches. After crushing and screening to remove impurities, the materials are precisely mixed using a double axis paddle mixer according to a carbon-nitrogen ratio of 25-30:1 and a moisture content of 55%-60%, laying a solid foundation for microbial fermentation.

Step 2: Microbial Activation and High-Temperature Fermentation: Select high-efficiency microbial strains such as Bacillus subtilis, activate and expand them, and then mix them into the raw materials. Regular turning is performed using a compost turning machine, controlling the temperature at 55-65℃ and the pH value at 6.5-7.5. Fermentation takes 7-15 days to ensure thorough decomposition, kill pathogens, and preserve microbial activity. This is the core of the production process.

Step 3: Post-treatment and Granulation: The fermented material is dried at low temperature (moisture content ≤20%), crushed, and screened. Granulation is then performed using a double roller press granulator, balancing efficiency and microbial activity while avoiding high-temperature damage.

Step 4: Testing and Storage: The finished product is tested for indicators such as organic matter and effective viable bacteria count. After meeting the standards, it is packaged and stored. Storage requires ventilation, dryness, and protection from light and moisture. The entire process relies on a complete set of bio-organic fertilizer equipment to achieve continuous mass production.

In summary, the key to large-scale production is precise raw material proportioning, controllable fermentation, and coordinated equipment, ensuring both mass production and fertilizer quality, contributing to green and circular development in agriculture.

Basic knowledge of large-scale composting on dairy farms: From raw materials to maturity

Large-scale composting on dairy farms is a key path to the resource utilization of manure and alleviating environmental pressures. The core is the transformation of dairy cow manure into high-quality organic fertilizer through microbial fermentation.

Raw material ratio is a prerequisite for successful composting. The core raw material is fresh dairy cow manure with a moisture content of 70%-80%. It needs to be mixed with auxiliary materials such as straw and sawdust to adjust the carbon-to-nitrogen ratio and moisture content. The ideal carbon-to-nitrogen ratio is controlled at 25-35:1, and the moisture content is adjusted to 60%-65% (it should clump together when squeezed in the hand, with water seeping between the fingers without dripping). The auxiliary materials account for 30%-40%, which prevents the compost from smelling bad and provides sufficient energy for microbial activity.

The fermentation process focuses on large-scale, efficient maturation, often using windrow compost turners or trough-type compost turners. The compost pile height is 1.5-2.0 meters and the width is 3-5 meters to ensure air permeability and heat retention. Fermentation is divided into three stages: First, the temperature is raised to 55℃ for 1-3 days, then maintained at 55-65℃ for at least 3 days to kill pathogens and insect eggs. Finally, the temperature is lowered to below 40℃, allowing microorganisms to continue decomposing organic matter. Regular turning and aeration throughout the process promotes uniform composting.

Quality control and final stages determine compost quality. The maturity standard is: temperature reduced to room temperature, dark brown color, no fecal odor, and organic matter content ≥30%. After screening and impurity removal, qualified material can be directly used as core raw material in organic fertilizer production lines to process into commercial fertilizer. Material not connected to the production line must be stored in a well-ventilated and dry place to prevent moisture absorption.

Dry double roller press granulator: The high-efficiency choice for NPK compound fertilizer plants

As a crucial type of fertilizer granulator, the dry double roller press granulator is a core piece of equipment for large-scale production of NPK compound fertilizers. With its advantages of no drying required, low energy consumption, and strong adaptability, it is suitable for various nitrogen, phosphorus, and potassium raw material ratios.

Dry granulation is its core advantage, meeting the diverse needs of NPK fertilizer production lines. Compared to wet granulation equipment, this fertilizer granulator eliminates the need for high-temperature drying, directly pressing the uniformly mixed NPK raw materials into shape through double-roller extrusion. This significantly saves energy and avoids nutrient loss caused by high temperatures, ensuring that the compound fertilizer nutrients meet precise standards.

Its adaptability is perfectly suited to the factory-scale scenarios of NPK fertilizer production lines. It can process various NPK basic raw materials such as urea and monoammonium phosphate, without complex pre-treatment. Parameters can be easily adjusted to meet the production needs of compound fertilizers with different nutrient ratios. The formed granules have high strength and are not prone to caking, making them suitable for subsequent screening and packaging processes.

The core structure is designed for large-scale operations. The double rollers are made of wear-resistant materials, reducing wear and downtime for maintenance. The feeding and roller speeds can be precisely controlled, ensuring uniform particle size and meeting the standardized production requirements of NPK compound fertilizers, while also producing no wastewater or exhaust gas emissions.

This fertilizer granulator provides NPK fertilizer production lines with energy efficiency, high efficiency, and quality, adapting to small, medium, and large-scale production capacities. It can meet diverse production needs while reducing overall costs.

Wet granulation vs. Dry granulation: Core process differences and selection criteria

Wet granulation and dry granulation are core processes in compound fertilizer granulation. The main difference lies in whether water is added and the molding principle, adapting to different production needs. Selection should consider environmental factors, fertilizer type, and scale of production; there is no absolute superiority or inferiority between the two.

The core process and raw material suitability differ. Wet granulation of compound fertilizers requires the addition of binders and water, followed by granulation, drying, and cooling. It is suitable for low-moisture, non-caking raw materials, improving nutrient uniformity, but it can easily damage heat-sensitive components such as microbial agents. Dry granulation does not require water or drying, relying on high-pressure extrusion for molding. It is suitable for high-moisture raw materials or heat-sensitive formulations, reducing nutrient loss, and the process is simpler.

Energy consumption, environmental impact, and particle quality differ. Wet granulation requires drying equipment, resulting in high energy consumption and a small amount of wastewater that needs treatment; the granules are round and have good solubility, suitable for foliar fertilizers and drip irrigation fertilizers. Dry granulation of compound fertilizers has low energy consumption and no wastewater, meeting environmental requirements; the granules have high strength and are less prone to caking, suitable for general field fertilizers, and convenient for storage and transportation, but the regularity is slightly poorer.

The suitability for different scales of production varies significantly. Wet granulation equipment requires high investment and is suitable for large-scale continuous production, adapting to complex formula compound fertilizers. Dry granulation equipment requires moderate investment, suitable for both small-scale trial production and large-scale mass production, adapting to NPK general fertilizers and special compound fertilizers, offering greater flexibility.

In summary, choose wet granulation if you prioritize particle appearance and solubility; choose dry granulation if you prioritize environmental protection, energy saving, and nutrient retention.

Choosing the right bio-organic fertilizer for optimal growth! A guide for different crops

There is no “one-size-fits-all” bio-organic fertilizer. Its core value lies in improving soil and supplementing nutrients, and its suitability directly affects crop growth. High-quality bio-organic fertilizers require processing using bio-organic fertilizer equipment to ensure proper decomposition and microbial activity. The key is to choose the right type based on crop type and growth needs.

For field crops (wheat, corn, etc.), choose bio-organic fertilizers with high organic matter and slow-release properties, preferably those containing Bacillus subtilis. Standardized mass production using bio-organic fertilizer production lines and equipment allows for controlled nutrient ratios, providing a slow release of nitrogen, phosphorus, and potassium, improving soil compaction, and reducing the frequency of top dressing, which is ideal for large-scale field cultivation.

For fruit and vegetable crops (tomatoes, strawberries, etc.), prioritize products rich in probiotics and high in humus. Organic fertilizers containing lactic acid bacteria are suitable, promoting root development, enhancing stress resistance, reducing pests and diseases, supplementing trace elements, improving fruit taste, and preventing fruit deformities.

For flowers and seedlings, choose loose, well-aerated, low-concentration bio-organic fertilizers, preferably those made from decomposed leaves and microbial residues. The nutrients are gentle, improving soil aeration, promoting flower bud differentiation, preventing root burn and soil compaction, and enhancing the ornamental value of the plants.

The key to selection: Prioritize products standardized through bio-organic fertilizer production lines to ensure sufficient decomposition and high microbial activity, preventing root burn; and choose the right type based on the crop’s nutrient requirements to make it a “booster” for crop growth.

A comprehensive analysis of common compound fertilizer production processes

Compound fertilizer production processes are diverse, with core differences focusing on raw material processing, granulation methods, and energy consumption control. Different processes are suited to different fertilizer types and production capacity requirements. The following outlines the core characteristics and application scenarios of four major processes, providing a reference for production selection.

Rotary drum granulation is a traditional mainstream wet process. Raw materials are sprayed, mixed, and granulated in a rotary drum, followed by drying, cooling, and screening to complete production. Its advantages include high production capacity and uniform granules, making it suitable for general-purpose NPK compound fertilizers; its disadvantages include high energy consumption and strict control over raw material moisture content.

Spray granulation emphasizes high efficiency and integration. The raw material slurry is directly sprayed into a granulation tower, where it is rapidly dried and formed by hot air, without the need for additional mixing. It offers uniform nutrient distribution and high efficiency, making it suitable for large-scale production of high-concentration compound fertilizers, but it requires high equipment investment and has stringent requirements for slurry viscosity.

Dry extrusion granulation is an environmentally friendly and energy-saving process. Dry raw materials are directly pressed into shape using a double roller press granulator, eliminating the need for water addition and drying. Energy consumption is more than 30% lower than wet processes, and there is no wastewater or exhaust gas. It is suitable for various raw materials and small-to-medium-scale environmentally friendly production, although the granule strength is slightly lower.

Blending granulation focuses on flexibility. Single fertilizers are mixed according to the formula using a double axis paddle mixer, and then granulated or made into BB fertilizer as needed. It offers flexible formulations and convenient product changes, making it suitable for customized production, but it requires high consistency in raw material particle size.

Advantages and disadvantages of BB fertilizers: Value determined by suitability

BB fertilizers, or blended fertilizers, are made by mixing two or more single-element fertilizers or compound fertilizers in a specific ratio. They require no complex granulation process and their flexibility has secured them a place in agricultural production.

The core advantages of BB fertilizers are their flexibility and economy. Formulas can be customized to precisely suit different soil fertility levels and crop needs, adjusting the proportions of nitrogen, phosphorus, potassium, and trace elements. Their adaptability far exceeds that of fixed-ratio compound fertilizers, making them particularly suitable for specialty crops and regional soil improvement. The production process is simple; the core blending process can be completed using a BB fertilizer mixer, eliminating the need for complex granulation equipment and a complete NPK blending fertilizer production line. This significantly reduces processing costs and ensures high raw material utilization, minimizing nutrient waste.

The disadvantages stem from the inherent limitations of their blending characteristics. They have poor physical stability; different raw materials have varying particle sizes and specific gravities. Even after being uniformly mixed in a BB fertilizer mixer, they are prone to stratification and clumping during transportation and storage, affecting the uniformity of fertilization and leading to uneven crop growth. Uncoordinated nutrient release and lack of synergistic slow-release effect can easily lead to partial nutrient loss and insufficient supply. It also requires high purity of raw materials and precise blending.

In summary, BB fertilizer is suitable for small-scale, personalized planting scenarios, accurately matching differentiated needs. In large-scale, standardized planting, it needs to be paired with professional fertilizer production equipment to control the precision of the ratio and to manage storage effectively in order to avoid shortcomings and maximize advantages.

The use of granular potassium fertilizer in agriculture offers several undeniable benefits

Potassium fertilizer is a vital element for crop growth. Granular potassium fertilizer, an important type of NPK fertilizer, is processed using NPK fertilizer production lines and fertilizer granulators. Compared to traditional powdered potassium fertilizer, its granular form optimizes application, improves fertilizer efficiency, and protects the soil.

Convenient storage and transportation. Granular potassium fertilizer processed by a granulator is compact and less prone to caking. Transportation is dust-free and prevents scattering, avoiding the waste associated with powdered potassium fertilizer that absorbs moisture, cakes, and disperses. Storage does not require complex moisture-proof measures; it remains loose even after long-term storage, making it easy for farmers to use and manage, reducing storage and transportation costs.

Precise application. The fertilizer granulator ensures uniform particle size, making it suitable for mechanized sowing and topdressing, eliminating the need for manual crushing, saving labor and effort. During application, it does not stick together and distributes evenly, preventing localized high concentrations that can burn seedlings, reducing nutrient volatilization, and allowing potassium to act precisely on the crop roots, improving application efficiency.

Long-lasting fertilizer effect. Granular potassium fertilizer dissolves gradually and releases potassium slowly, avoiding the drawbacks of rapid-acting potassium fertilizers and extending the fertilizer effect period. The granular form also reduces contact with the soil, reducing nutrient fixation and promoting gradual absorption by the roots, improving utilization efficiency.

Soil protection and wide applicability. It has minimal irritating effects on the soil, reduces soil compaction, and balances fertilizer efficiency with soil protection. Whether for field crops, cash crops, or fruit trees, it can be flexibly adapted, and supported by professional fertilizer production equipment, it contributes to green and efficient agricultural production.

NPK and specialty compound fertilizer dry granulation: Process differences and practical considerations

Dry granulation is an environmentally friendly and efficient production process for compound fertilizers. It requires no high-temperature drying or additional water, relying on mechanical pressure for shaping. It is suitable for the production of both general-purpose and specialty compound fertilizers on NPK fertilizer production lines. The core aspects are formula adaptation and process parameter control.

Dry granulation of NPK compound fertilizers focuses on nutrient uniformity and granule strength. Nitrogen, phosphorus, and potassium raw materials are crushed and screened, then mixed according to the formula ratio, and fed into a double roller press granulator to be pressed into sheets. These sheets are then crushed and screened to obtain uniform granules. Strict control of raw material fineness and mixing is necessary to avoid nutrient segregation. This process is suitable for general-purpose field fertilizers, resulting in high granule strength and resistance to caking, meeting the needs of large-scale production lines.

Dry granulation of specialty compound fertilizers requires adaptation to customized formulas, often including the addition of trace elements and microbial agents. During granulation, pressure parameters need to be optimized to avoid damaging heat-sensitive components. Extrusion or roller press granulation equipment is used, and granule size is adjusted to suit precision farming, ensuring that special nutrients are not lost and that fertilizer efficacy is precisely released.

For both types of granulation and production line operation, two key points must be controlled: raw material moisture content should be controlled at 5%-8% to avoid adhesion or difficulties in molding; and equipment should be regularly inspected to ensure uniform granules. Dry granulation has low energy consumption and produces no wastewater, meeting the environmental requirements of the production line.

In summary, the core of dry granulation for both types of fertilizers is formula adaptation to the process. NPK compound fertilizers are adapted for large-scale production lines, while specialty fertilizers prioritize the protection of special nutrients.