RU2045197C1 - Method for processing waste of poultry farms - Google Patents

Abstract

FIELD: agriculture. SUBSTANCE: method involves reduced losses of marketable products by preventing dung from sticking to the walls of the drying installation, and reducing losses of valuable and useful components in the course of drying. For this purpose the method involves conveying by augers the initial moist poultry dung from accumulating container into the metering device, delivering moist dung into the drying installation in a primarily dispersed form. EFFECT: higher quality of marketable product and increased labor productivity. 2 cl

Description

 The invention relates to agriculture, in particular to methods for processing waste generated in poultry enterprises, and can be implemented in poultry farms for processing poultry manure to produce marketable products of feed additives, fertilizers, etc.

 Fresh bird droppings are a mass of gray-green color of a porous structure with a moisture content of 60-85%. Raw bird droppings, on the one hand, are a dangerous source of pollution of the environment, soil, water sources, air basin; in unprocessed form, raw bird droppings create inconvenience for the population during its transportation, storage and introduction into the soil. On the other hand, raw bird droppings are a valuable source of raw materials for fertilizers and feed additives, as it contains a large number of useful components: nitrogen, phosphorus, potassium and a significant amount of trace elements: magnesium, calcium, boron, sulfur, etc.

 To create normal sanitary and veterinary conditions at poultry enterprises, as well as to preserve the main nutrients in poultry manure, improve its physical and chemical properties, a number of different methods for processing poultry manure to produce marketable products have been developed: biothermal, biological, chemical, composting, hydraulic treatment; methods based on electroosmosis, microwave energy drying, mechanical and thermal dehydration.

A known method of biothermal processing of bird droppings. A known method is as follows. Raw droppings with a moisture content of not more than 60-65% are loaded into special pits constructed from moisture- and heat-resistant material. On top of the pit close tight lids with holes for air flow. After 20-25 days after loading of manure in the pit temperature rises to 60 ^C. The raw material of decomposition process ends for 35-40 days; this forms a homogeneous, odorless compost suitable for fertilizer [1]
The disadvantage of this method is the low productivity and the need for additional drying to ensure transportation, storage and subsequent dosage.

 A known method of processing bird droppings, which consists in the following.

The initial, raw (vl. 60 85%) bird droppings are initially sent to a vibrating screen to remove foreign objects, then they are fed with a screw batcher into a metering mixer to mix the wet droppings with part of the dried droppings (to reduce humidity). Then the resulting mixture is conveyed by a screw conveyor into a direct-flow drying drum. Drying (dehydration) is carried out at temperatures in the early drying unit 900 1,000 ° ^C, at the end of 120 160 ° ^C. From the drying drum through the manure discharge is supplied to Chopper for crushing large lumps of dried manure and then in a cooling tower for cooling the finished product.

 Thus obtained product has a moisture content of 12-14% and is a lumpy crumb with a granule size of 1 to 10 mm. From the cooling column, the dried manure is sent by a conveyor to the accumulator, from which the finished product is packaged and / or shipped to consumers.

 The disadvantages of the known method are as follows: sticking of raw manure to the drum walls and, therefore, burning of manure, reduction in the quality and consumer properties of the finished product: reduction in the content of nutrients, useful components; the need for special grinding of the finished product; heterogeneity (1-10 mm) of the dried and crushed product. The disadvantage of this method is the need to return the dried product to the "head" of the process to reduce the moisture content of the original product entering the drum for drying. This, in turn, leads to a decrease in the productivity of the method as a whole.

 The claimed technical solution is aimed at solving the problem of reducing the loss of commercial products by preventing the buildup of wet manure on the walls of the drying unit, improving the quality of the resulting product and increasing the productivity of the process.

These tasks are solved by the proposed method for processing waste from poultry farms (bird droppings), the essence of which is expressed by the following set of essential features: screw conveyance of the initial wet bird droppings from the storage tank to the dispenser; introducing litter into the drying chamber in a preliminary dispersed form (in the form of a gas suspension, aerosol) with an initial speed of 25-100 m / s; coolant gas supply to the working volume of the chamber at a speed of 5-40 m / s; the implementation of the process with the ratio of the rate of introduction of the litter into the working volume of the drying chamber (V _p ) and the feed rate of the gas-coolant (V _g.t. ) equal to V _p : Vg.t = (2-5): 1; unloading of the finished product and its packaging.

 Salient features of the claimed method is that the initial wet bird droppings are introduced into the drying chamber in a pre-dispersed form with an initial speed of 25-100 m / s, and the heat carrier gas is fed into the drying chamber at a speed of 5-40 m / s.

An essential distinguishing feature is the fact that the process is carried out at a ratio of the rate of introduction of chicken manure (V _p ) and the flow rate of gas-coolant (V _g ), equal to
V _p : V _gt (2-5): 1.

 As shown by experimental and pilot tests, the specified conditions for the implementation of the proposed method provide, ceteris paribus, the achievement of a technical result, which consists in the following: preventing sticking of wet manure on the walls of the drying unit; improving the quality of the finished product by eliminating the burning of litter on the walls and in this regard, reducing the loss of useful components present in the original litter; increasing the productivity of the process by eliminating the special operation of grinding the dried product and returning part of the dried litter to the "head" of the process.

 Analysis of the totality of the features of the invention with the technical result achieved in this case shows that there is a well-defined causal relationship between them, expressed as follows.

 It has been experimentally established that the processing of pre-dispersed (as a gas suspension) bird droppings introduced into the drying chamber at a speed of 25-100 m / s and a flow rate of heat carrier gas of 5-40 m / s prevents sticking and burning of the litter on the walls of the drying chamber unit, improves the quality of the resulting product and increases the productivity of the process.

 Information confirming the possibility of carrying out the invention is given in the examples.

A batch (10 t) of raw chicken manure with an initial moisture content (64 ± 2%) was placed in a storage tank, from which it was fed with a screw into the dispenser, from the dispenser, wet manure entered the disperser, and then into the drying chamber. Litter during the experiments was introduced into the drying chamber in the form of a gas suspension (aerosol). In this case, the litter input rate in various experiments was varied from 20 to 120 m / s. At the same time, the heat carrier gas was supplied to the dryer pipe at an initial temperature of 500-1000 ^о С. At that, the specific heat consumption per 1 kg of dry bird droppings (recalculation to humidity of 10%) was 4320 kJ during the experiments. The flow rate of the coolant gas was varied in the range from 3 to 45 m / s.

 At the outlet of the dryer pipe, through the unloading device, the finished product was unloaded and packaged in plastic bags.

 A sample of the obtained product in each experiment was weighed, the moisture content of the product was determined, its losses were calculated, then the particle size distribution, bulk density and quality of the obtained product were determined, which was evaluated by the content of valuable components, in particular protein. More detailed studies were carried out with individual samples.

_{PRI me} R 1. Drying of the litter was carried out at a feed rate of the litter in the drying volume (V _p ) of 50 m / s, and a feed rate of the coolant gas (V _g ) 25 m / s. The ratio of the feed rates into the drying chamber of the litter and the heat carrier gas 2: 1. With a specific heat consumption per 1 kg of dry bird droppings of 4320 kJ, the product with a moisture content of 10% was obtained. The loss of the target product was caused only by the efficiency of the dust collecting equipment (dust collecting cyclones) and amounted to ≈ 2% on the amount of raw materials loaded.

PRI me R 2. The same as in example 1, but V _p 25 m / s; V _gt 5 m / s; (V _p : V _{g t} = 5: 1). Received a product with a moisture content of 10%. Product loss was ≈ 2%.
PRI me R 3. The same as in examples 1 and 2, but V _p = 100 m / s; V _gt = 40 m / s; the ratio of V _p : V _gt = 2.5: 1. Product Humidity 10% Product Loss ≈ 2%
Examples 1-3 are carried out under optimal conditions for the implementation of the method (with optimal parameters and modes of the drying process). In this case, there is no burning, sticking of raw materials, product to the walls of the drying chamber. Losses of the target product are minimal. EXAMPLES 4-11 were carried out under conditions in which the process of drying chicken droppings was carried out at non-optimal parameters (at different rates of introducing droppings and supplying heat carrier gas to the drying chamber and other than the optimal ratio V _p : V _gt ).

PRI me R 4. The same as in examples 1-3, but V _p = 20 m / s; V _g.t = 5 m / s, i.e. at V _p <V _opt . A product with a moisture content of ≈ 10% was obtained, however, the loss of the target product was 7%. During the experiment, a significant burning of the feedstock was observed at the input section of the drying chamber.

PRI me R 5. The same as in examples 1-3, but V _p = 120 m / s; V _p > V _{g opt} ; V _gt = 5 m / s; the ratio of V _p : V _gt = 24: 1. A product with a moisture content of 15% was obtained (this is obviously due to a decrease in the residence time of the raw materials in the drying unit. Losses of the product with dust amounted to 1%, however, the resulting product is completely substandard (100% fermentation) and further processing is required.

PRI me R 6. The same as in examples 1-3, but V _p = 20 m / s; V _p <V _{p opt} ; V _g.t. 40 m / s, the ratio of V _p : V _gt = 0. Product humidity ≈ 10% Product losses amounted to 8% (apparently due to intense overheating of the product in the drying chamber, grinding of the product and its mixing with the formation of a large number of difficult to catch small (less than 10 microns) particles of the product.

PRI me R 7. The same as in examples 1-3, but V _p = 120 m / s; (V _p > V _{g. Opt} ); V _g.t = 40 m / s. Product humidity ≈ 17% (this is obviously due to the short residence time in the drying zone). The product is substandard and must undergo additional heat treatment.

EXAMPLES 8-11 were carried out at optimal values of the parameter V _p = 25-100 m / s, but when _{exceeding the} optimal values of the parameter V _g .

PRI me R 8. The same as in examples 1-3, but V _p = 25 m / s; V _gt = 3 m / s; V _gt <V _{gt (optim)} and the ratio of V _p : V _gt = 8: 1. In the course of the experiment, both burning of the material on the walls of the drying unit and the formation of large difficultly dehydrated units were observed. Product Humidity ≈ 13% Product Loss ≈ 7%
PRI me R 9. The same as in examples 1-3, but V _p = 25 m / s; V _gt = 45 m / s; (V _gt > V _{gt optim} ) and the ratio of V _p : V _gt = 5.6: 1. Product humidity ≈ 10% Loss increased to ≈ 8%
PRI me R 10. The same as in examples 1-3, but V _p = 100 m / s; V _g.t. = 3 m / s (V _gt <V _gtoptim ) and the ratio of V _p : V _gt = 33: 1. A product with a moisture content of ≈ 11% was obtained; however, the product loss was ≈ 8%. During the experiment, the occurrence of the material and its further burning to the walls of the drying unit were observed.

PRI me R 11. The same as in examples 1-3, but V _p = 100 m / s; V _gt = 45 m / s; (V _g.t. <V _{g.t. opt} ). Product humidity ≈ 17%, which is obviously due to the short residence time of the material in the drying zone.

 In the table. 1 shows the conditions for the described experiments and summarizes the results obtained.

 In the table. 2 shows a comparison of the main indicators of the processes of processing chicken manure according to the known, [2] and the proposed methods.

Claims (2)

 1. METHOD FOR PROCESSING WASTE OF Poultry Poultry Wastes, including loading the initial wet litter into the drying chamber, supplying heat carrier gas to it, drying the litter, followed by unloading and packaging of the finished product, characterized in that the litter is loaded into the drying chamber in a preliminary dispersed form the speed of entry into the working volume of the chamber 25 100 m / s and the flow rate of the gas coolant 5 40 m / s.  2. The method according to claim 1, characterized in that the process is conducted at a ratio of the rate of introduction of the litter into the working volume of the drying chamber and the flow rate of the heat carrier gas (2 5) 1.

Images