RU2468569C1 - Method to recycle emissions of hazardous admixtures in air of stock-raising premises - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to agriculture. The method consists in additional fertilising of plants with carbonic acid gas and nitric fertilisers due to supply of air with a mixture of gases along pipelines from a stock-raising room into a system of aeration drainage of a soil layer of greenhouses. In periods between crop combinations these emissions are supplied to sites for preparation of substrates from organic materials, volume of which is determined using the following formula:

where W - volume of composted organic material, m³; 24 - number of hours per day;

- quantity of ammonium discharged from a stock-raising room, kg/hr/head; T_com - period of composting, days; K₁ - content of nitrogen in ammonium, %; N - number of animal heads in a stock-raising room; G_fert - quantity of nitric fertilisers, which are to be introduced in composting of organic materials, kg/m³; K₂ - nitrogen content in a fertiliser used for composting, %.

EFFECT: invention makes it possible to increase environmental compatibility of a stock-raising complex.

Description

The invention relates to agriculture, in particular to the protection of the environment from harmful emissions from livestock buildings.

A known method of keeping animals (RF patent No. 2076588, A01K 5/00), including feeding animals with green fodder obtained in the plant during their cultivation, removing manure from the livestock building into a storage tank, taking off the exhaust air from the livestock building and feeding it into a plant, the use of oxygen-enriched air from a plant in a livestock building. Manure before feeding into the tank is divided into solid and liquid fractions, moreover, the liquid fraction is diluted with water in a ratio of 1: 5-1: 10 and used in the plant for growing green feed, the solid fraction is stored in the tank, and the heat and gas released in it at the course of the biothermal process, used for technological needs, respectively, for heating water or air in the greenhouse when burning the above gas.

The disadvantages of this method are:

one). Heat and gas, which is obtained only from the storage capacity of the solid fraction of manure.

2). Do not use ammonia, secreted by animals in the process of life.

Also, a method is known for cleaning air emissions and wastewater of livestock complexes using plants (RF patent No. 2179158, C02F 3/32, C05F 7/00), including the removal of contaminated air using an air pump, dissolving it in water and growing it with plant lighting. Plant cultivation is carried out in containers arranged in tiers on the walls of the housing with tilted bottoms having reflective outer surfaces toward the walls of the housing, while lighting is carried out using lamps located in the center of the housing between the rows of tiers of containers.

The disadvantages of the method are as follows.

1. The walls of the case are made of reflective material, so it is necessary to use labor-intensive additional operations, which ultimately complicates the manufacturing technology. When growing plants, there is an increased content of relative air humidity, as a result of which the walls of the body will fog up, which reduces the reliability and efficiency of the structure.

2. The presence in the drains of a large number of microbiological contaminants, fungi, bacteria, helminth eggs, etc. All these bacteriological and microbiological organisms can be transmitted through animal feed, which negatively affects the health of the animal.

3. The water supplied to the tank for growing plants is not heated, and therefore negatively affects the growth and development of plants.

Closest to the proposed method relates to "a method of feeding plants in greenhouses with carbon dioxide and nitrogen fertilizers" (RF patent No. 2192120, A01G 7/02, A01G 9/18), including the supply of air with a mixture of gases from the livestock building to the greenhouse. Air with a mixture of gases is fed into the greenhouse using pipelines and an aeration drainage system, which is the soil layer of the greenhouse, the volume of which is determined by the formula for feeding plants with carbon dioxide

where T _s = 24 hours;

G _1K - emission of CO _{2 in} one animal, kg / h;

N is the number of animals on the farm;

P - the norm of additional fertilizing plants in greenhouses with carbon dioxide, kg / m ² h;

T _p - the time of additional fertilizing plants with carbon dioxide during the daylight hours - 4-6 hours;

G is the emission of carbon dioxide by animals during the day, kg,

and its volume by the absorption of nitrogen fertilizers in ammonium form is determined by the formula

where V is the volume of the soil layer in the greenhouse, m ³ ;

G is the ammonia content in the ventilation emissions of the livestock building formed during the day, kg;

T _in - the growing season of growing plants in the greenhouse, days;

h is the thickness of the soil layer in the greenhouse, m;

P - nitrogen consumption by one plant during the growing season (T _in days), kg / pc .;

n is the number of plants growing per 1 m ^{2 of the} greenhouse, pcs / m ² ;

while the final volume of the soil layer of the greenhouse is determined by the maximum value of the obtained volumes.

The disadvantage of this method of using ventilation emissions from livestock buildings is that plants consume nitrogen unevenly during the growing season. With continuous supply of air from the livestock building to the greenhouse soil during the entire growing season of growing plants, it may form an excess of nitrogen fertilizers, especially in the form of ammonia compounds NH ₄ ⁺ , which can cause damage to plants especially in the first months after transplanting.

The objective of the invention is the implementation of the excess ventilation emissions from the livestock building after feeding plants according to agrotechnical requirements, which will lead to the full implementation of emissions from the livestock building and, as a result, to solve the problem of improving environmental protection.

The problem is solved due to the fact that the method of utilizing emissions of harmful impurities in the air of livestock buildings includes feeding plants with carbon dioxide and nitrogen fertilizers by supplying air with a mixture of gases through pipelines from the livestock building to the aeration system of the soil layer of greenhouses. In the periods between cultural turnover, these emissions are fed to platforms for the preparation of substrates from organic materials, the volume of which is determined by the formula

where W is the volume of compostable organic material, m ³ ;

24 - the number of hours in a day;

G _NH3 ^h - the amount of ammonia emitted from the livestock building, kg / h / goal;

T _com - the period of composting, days;

K ₁ - nitrogen content in ammonia,%;

N is the number of animals in the livestock building;

G _beats - the amount of nitrogen fertilizers that should be applied when composting organic materials, kg / m ³ ;

K ₂ - nitrogen content in the fertilizer used for composting,%.

New significant features:

1. In the periods between cultural turnover, emissions are fed to sites for the preparation of substrates from organic materials.

2. The volume of organic materials is determined by the formula

where W is the volume of compostable organic material, m ³ ;

24 - the number of hours in a day;

G _NH3 ^h - the amount of ammonia emitted from the livestock building, kg / h / goal;

T _com - the period of composting, days;

K ₁ - nitrogen content in ammonia,%;

N is the number of animals in the livestock building;

G _beats - the amount of nitrogen fertilizers that should be applied when composting organic materials, kg / m ³ ;

K ₂ - nitrogen content in the fertilizer used for composting,%.

The listed new essential features in combination with the known ones allow to obtain a technical result in all cases to which the requested amount of legal protection applies.

The technical result is achieved by the fact that the air from the livestock room containing impurities of carbon dioxide and ammonia is taken around the clock from the lower zone of the livestock room, where the concentration of these impurities is maximum. At the same time, a constant influx of fresh air into the room due to the upper air inlets in the livestock building should be ensured.

The air taken from the livestock building is sent through a piping system to the drainage system of sites for the preparation of substrates from tree bark and other organic materials between crop rotations, and during periods of active growth and development of plants, it is sent through the drainage network of greenhouses to an adsorption device, which is a layer of greenhouse soil with a height of 0.25 ... 0.3 m.

According to published data (N.P. Kozlova, N.V. Maksimov. Estimation of carbon dioxide and ammonia emissions from cowsheds. / Reducing the negative environmental impact of reactive nitrogen in agricultural production. Materials of the workshop on December 10, 2009. - SPb .: GNU SZNIIMESKh of the Russian Agricultural Academy, 2010. - P.114-122), during periods when the outdoor temperature is t _H ≤0, the concentration of ammonia in the air of the barn q _NH3 = 8 mg / m ³ , and at a temperature t _H ≥0 the concentration of ammonia in the air is q _NH3 = 4.5 mg / m ³ . The minimum air exchange V _{min of} cowsheds according to the norms of NTP 1-99 is 15 m ³ / h per centner of live weight of the animal.

For cowsheds with animals weighing 500 kg V _min = 75 m ³ / h · goal, the maximum in summer is usually taken equal to V _max = (3 ... 4) × V _min , i.e. about 225 ... 300 m ³ / h · goal. According to the same source, V _min ^cp = 88 m ³ / h · goal, and V _max ^cp = 149 m ³ / h · goal.

The output of ammonia in the winter season was G _s = 88 × 8 = 704 mg / h or 0.0007 kg / h, in the warm season G _p = 149 × 4.5 = 670.5 mg / h or 0.00067 kg / h

Thus, we can assume that the ammonia output from the barn is on average: G _NH3 ^cp = 0.0007 kg / h / goal, then the ammonia output per day will be G _NH3 ^cp = 24 × 0.0007 = 0.0168 kg / hl , and for the year - G _NH3 ^cp = 0.0168 × 365 = 6.13 kg / goal. Ammonia output from the barn during the composting period, for example, of tree bark (on average over 3 months): G _NH3 ^com = 0.0168 × 90 = 1.51 kg / goal.

By international standards, it is generally accepted that the annual output of ammonia from a livestock farm is 11 kg / head / year. We will take in our examples a greater importance, namely: 11 kg / goal / year. Then, in contrast to the data given above, the daily output is G _NH3 ^sut = ^11/365 = 0.03 kg / goal, the hourly output is G _NH3 ^h = 0.03 / 24 = 0.00125 kg / goal, and the ammonia yield for the composting period of tree bark - G _NH3 ^com = 0.03 × 90 = 2.7 kg / goal. Thus, the amount of ammonia that can be used to prepare the substrate for 3 months, for example, from tree bark, can vary from 1.5 to 2.7 kg / goal. Ammonia contains 82.3% nitrogen. Then the yield of pure nitrogen during this time will be from 1.24 to 2.22 kg / goal.

To prepare a substrate from wood bark, 4.3 kg / m ^{3 of} urea, which contains 46% nitrogen, is required. In terms of pure nitrogen, 4.3 × 0.46 = 1.98 kg N should be added for composting. This value of nitrogen required for composting 1 m ^{3 of} tree bark is higher than the values for the nitrogen output from the livestock building obtained experimentally (1 , 51 kg / goal), but lower than the values obtained on the basis of calculations according to accepted international standards (2.7 kg / goal). Therefore, the formula for calculating the volume of composted material takes the form

where W is the volume of compostable organic material, m ³ ;

24 - the number of hours in a day;

G _NH3 ^h - the amount of ammonia emitted from the livestock building, kg / h / goal;

T _com - the period of composting, days;

K ₁ - nitrogen content in ammonia,%;

N is the number of animals in the livestock building;

G _beats - the amount of nitrogen fertilizers that should be applied when composting organic materials, kg / m ³ ;

K ₂ - nitrogen content in the fertilizer used for composting,%.

The saving of nitrogen fertilizers when composting wood bark, sawdust, and other materials is determined by the formula

Example 1

The cattle livestock house contains 100 heads of dairy cows weighing 500 kg each with a milk yield of up to 30 liters. The ammonia content in the air of the barn is an average of 7 mg / m ³ . In the cold season from October to January, the indoor air exchange is about 88 m ³ / h per head, in the warm season -149 m ³ / h · goal.

The amount of ammonia that is released during ventilation of livestock buildings during the day per one animal is from:

G _NH3 ^days = 10 ^-6 × 24 × q _NH3 × V _vent = 10 ^-6 × 24 × 7 × 88≈0.015 kg / goal.

and up to: G _NH3 ^days = 10 ^-6 × 24 × q _NH3 × V _vent = 10 ^-6 × 24 × 7 × 149≈0.025 kg / goal.

On a farm of 100 animals, the amount of ammonia released per year will be

G _NH3 ^year = G _NH3 ^days × 365 = (0.015 + 0.025) / 2 × 365 × 100 = 730 kg.

We use urea as a nitrogen fertilizer for preparing a substrate from wood bark. The composting period of the tree bark is taken equal to T _com = 90 days. Then the volume of the obtained substrate from the tree bark will be equal to

Thus, for a composting period T _com = 90 days, a cattle farm of 100 animals can throw about 148 kg of pure nitrogen, which is part of ammonia. Due to these emissions, it is possible to compensate for the consumption of nitrogen fertilizers in the form of urea in the amount of

G _beats ^com = 4.3 × 75 = 322 kg, which is 148 kg of pure nitrogen.

The substrate obtained after composting can be used in greenhouses for growing vegetables in the area

F = W / 0.25 = 75 / 0.25 = 300 m ² .

In the rest of the year, the air pumped out of the barn can be used for supply to greenhouses through the drainage system for feeding plants.

Example 2

When using sawdust as substrates, a layer of 0.25 m per area of 1000 m ^{2 is} preliminarily made with 250 kg of ammonium nitrate, which contains 34% or 85 kg of nitrogen. Thus, per 1 m ³ of sawdust making 1 kg of ammonium nitrate.

The amount of sawdust that can "absorb" the ammonia released in the livestock building, which contains 100 heads of cows weighing 500 kg, during the preparation of the substrates, which is T _com = 60 days for sawdust, is determined by the formula

where G _beats = 1 kg / m ³ , K ² = 0.34.

F = W / 0.25 = 290 / 0.25 = 1160 m ² .

Saving nitrogen fertilizers during composting sawdust will be:

G _N ^ec = W × G _beats = 290 * 1 = 290 kg.

Example 3

For the Northwest zone, in winter block greenhouses, the most common is culture rotation with the cultivation of cucumber (from 1-20 / 1 to 25/7), tomato (from 1/8 to 10-15 / 12) and forcing crops (3 / 12- 3/1). In the first turn for fertilizing cucumber plants, it is recommended to apply nitrogen fertilizers every 10 days, based on nitrogen 10 g / m ² . Total for the growing season (210-240 days) is about 15 top dressing (excluded months after planting seedlings and at the end of the growing season of plants). The nitrogen consumption in this case can be G _N = 15 × 10 = 150 g / m ² or 0.15 kg / m ² . The nitrogen content of K ₂ for each type of fertilizer is different, in urea K ₂ = 46%. For greenhouses area 300 m ² (see. Example 1) _N G = 300 × 0.15 = 45 kg, and the dose amount of urea entering G ^fe = 45 _beats / 0,46≈98 kg.

In the second turn, when growing tomatoes, it is recommended to fertilize with nitrogen every 15-20 days. Excluding the first and last months, the amount of top dressing in the autumn period will be approximately 4 times 30 g / m ^{2 of} nitrogen. Thus, for the second revolution, the nitrogen consumption will be G _N = 30 × 4 = 120 g / m ² , for an area of 314 m ^{2 the} nitrogen consumption is G _N = 0.12 × 30 = 36 kg, and the fertilizer (urea) consumption will be G ^Connectivity _bpm = 36 / 0.46 = 78 kg. Total for plant nutrition in two turns on an area of 300 m ² requires 45 + 36 = 81 kg of nitrogen or 98 + 78 = 176 kg of urea.

For a greenhouse area of 1160 m ² (example 2), the nitrogen consumption during the growing season for top dressing cucumber plants will be G _N ^sub = 0.15 × 1160 = 174 kg, and for tomato plants G _N ^sub = 0.12 × 1160 = 139 kg , this will require the amount of fertilizer (depending on the type of fertilizer): ammonium nitrate G _beats ^sub = (174 + 139) / 0.34 = 921 kg, or urea: G _beats ^sub = (183 + 146) / 0.46 = 680 kg.

From the air of the livestock building, where 100 cows are located, for the period of feeding cucumbers and tomatoes 150 + 60 = 210 days, you can get G _NH3 ^pod = G _NH3 ^days × T _growing × N = 0.02 × (150 + 60) × 100 = 420 kg of ammonia. The utilization of ammonia by plants from the soil is 50 ... 75%, i.e. about 210 ... 315 kg of ammonia, or 173 ... 259 kg of nitrogen. This amount of nitrogen exceeds several times the amount of nitrogen required for top dressing of cucumber and tomato plants on an area of 300 m ² (45 + 36 = 81 kg).

The area of greenhouses for using this amount of ammonia as top dressings can be determined by the formula

F = (0.5 ... 0.75) × G _NH3 ^sub × K ₁ / G _N ^{specific pressure} = (0.5 ... 0.75) × 420 × 0.823 / (0.15 + 0.12) ≈640 ... 960 m ² , which is almost comparable with an area of 1160 m ² obtained by composting sawdust for 60 days. Fertilizer savings will be 921 kg of ammonium nitrate or 680 kg of urea.

In the periods between culture rotations (from December to January, when they do not feed plants, and in greenhouses grow distillation crops and plant new plants for about 70 days), fresh sawdust up to 0.1 m high is added, which will be W _subs = 1160 × 0.1 = 116 m ³ , which will require G _N ^subs = W ^subs × G _beats = 116 × 1 = 116 kg of nitrogen, or 116 / 0.46 = 252 kg of urea, or 341 kg of ammonium nitrate. The consumption of these fertilizers can be replenished by supplying air with an admixture of ammonia and carbon dioxide from the livestock building (G _N = 0.02 × 70 × 0.823 × 100 = 115 kg).

Since substrates from wood bark have been used for 2-3 years, and from sawdust up to 6 years, it is possible to further prepare substrates from organic materials either to expand the area of protected soil, or to transport them to the fields as fertilizers, or to replace waste substrates.

Claims (1)

A method of utilizing emissions of harmful impurities in the air of livestock buildings, including feeding plants with carbon dioxide and nitrogen fertilizers by supplying air with a mixture of gases through pipelines from the livestock building to the aeration drainage system of the soil layer of greenhouses, characterized in that during the periods between cultivation, these emissions are fed to platforms for the preparation of substrates from organic materials, the volume of which is determined by the formula:

where W is the volume of compostable organic material, m ³ ;
24 - the number of hours in a day;
G _NH3 ^h - the amount of ammonia emitted from the livestock building, kg / h / goal;
T _com - the period of composting, days;
K ₁ - nitrogen content in ammonia,%;
N is the number of animals in the livestock building;
G _beats - the amount of nitrogen fertilizers that should be applied when composting organic materials, kg / m ³ ;
K ₂ - nitrogen content in the fertilizer used for composting,%.