Dairy cow housing manure

Dairy cows are housed for most of the time in the barn. The fundamental for design the dairy barn is to provide cow comfort, labor efficiency, economic viability, and waste management efficiency [6][7][9]

One of long-standing and costly problems of handling manure has been the absence of simple, reliable, accurate and long-lasting system of manure collection and transportation out of the barn. The Enterprise tendency to lager dairy production, with a concern for quality of food in efficient environment, requires a number of radical changes and development of new methods for proper and efficient manure management.

Barn environment has a major influence on cows and the objective is to provide environment in the barn which will allow achieving optimal utilization of feed and highest production. In order to provide the dairy industry with adequate manure handling systems, which will be both technically and economically competitive, it is necessary to:

Develop the basic principles of design and construction of manure collection and transportation systems inside barns. The system should exclude manure storage in close proximity to cows in the barn and to keep the barn clean by applying plumbing technology principles. It means of using water for flashing manure.(proper sanitation)
Develop manure reception structure with flushing system, which will provide proper and automotive collection and removal of manure with minimum water consumption.
Develop typical floor details and piping system for the purpose of transportation liquid manure to the sump. Structure unification should allow modular design of the barn to accommodate any productivity. .
Develop new methods of calculation and designing manure handling systems to be completely automatic, that can be incorporated into a computerized plant control system.
Rational use of water would allow reducing the volume of wastewater. Most important it will allow selecting a proper manure treatment and utilization technology.
New technology should require minimum farmer attention and could be run with unskilled personnel
The technology requires multi-disciplinary research approach to focus on sustainability.

Extensive research, technological and development work permits consideration of the following approach (e.g. dairy barn designed by The University of Tennessee for 300- cow free stall and feeding facility retrofit illustrated in Fig.#1 and 2, and proposed modular design Fig.#3)[5][6]

The barn floor is divided by sections for manure collection arias with minimum construction volume, and equipped with flushing devise.
Manure -receiver equipped with flushing system for fully automatic removal of manure with moisture content in liquid of about 92% -95%
Unification of floor design will permit building the barn to allow some distance between floor and ground ( warm floor)
The completely new approach in design of the dairy barn has complete flexibility and allows increasing production in existing and new barns with high efficiency.

Manure collection and transportation design in the barn takes advantage of the positive aspects of traditional principals of plumbing design in the buildings it means separate manure collection devise and piping for transportation of wastewater. Developed method of calculation permitted to design efficient and reliable piping drainage system and manure collection fixtures, which will convey liquid manure to the sump.
The sump should have sufficient volume and equipped with pumps and agitation system, which will provide agitation of liquid manure during the pumping period. Manure has to be pumped out from the barn automatically.
The water supply system should be designed to provide portable-water for feeding, drinking, milking parlor and manure flushing. In a case where manure is treated and disinfected, the liquid can be used in a separate flushing system.
It should be noted that there are other engineering systems for barns that are well developed and should be used for design.
Since the barn engineering systems designed to be completely automatic, the controls of manure collection and removal should be incorporated into computerized barn control system.

Method of determining the system parameters

Manure production and characteristics for 1,400- pound lactating cow from [1][2] are Manure maximum- 68 liter/day, or 2,4 ft3/day with moisture - 87%

The volume of water for one time flushing for the project Fig. 1 will be [4][8][10] 56.775 liters or 15.000 gal ( from [3] Table 1} total minimum volume of flushing water 20.000 liters or 5.390 gal the total volume of manure from 300 cows with of 87% moisture.
77.175 liters or 20.000 gal the total volume of wastewater with moisture of 99.9%.

To find the volume of flushing water for the proposed projects using equation:

Vol (100 -M ) = Vol 1 ( 100 - M 1 )

Vol - manure volume from cow 68 liter or 17.97 gal [1],
M - moisture of cow manure of 87% [1],
M 1- moisture of wastewater after flushing at 95% maximum,
V 1 - volume of flushing water added,

Vol 1 = 176.8 liter/day or 46.71 gal/day per cow maximum water added.

The proposed retrofit project Figure 1 for calculation of maximum volume will be:

Modern Dairy Cow Housing Design Manure Management Technology - Image 1

53.040 liters or 14.013 gal The volume of flushing water at 95% of moisture.

20.400 liters or 5.390 gal The volume of manure from 300 cows with 87% of moisture.

73.440 liters or 19.403 gal The total volume of wastewater with moisture of 95%.

For proper working process of gravity transportation of drain piping it is important that moisture of liquid will be higher then 92% flow velocity at minimum of 1.2 m/sec or 4.0 ft/sec. Based on practice of the design of gravity flow of organic sludge at wastewater treatment plants.

The working volume of wastewater at around 92% moisture will be:

33,150 liters or 8,758 gal The volume offlushing water.

20,400 liters or 5.390 gal The total volume of manure.

53,550 liter or 14148 gal The total volume of wastewater with moisture of 92%will be 30% less to compare to conventional project

It is important to point out that new technology allowed to flush manure on demand several times a day with full control of flow rate of water. It means livestock producers will be able to fully control and automatically operate manure collection and removal and provide much better sanitation for cows and environment for working personal.

To design manure collection device with piping for flushing water supply and drainage (retrofit project Fig 1) the feed alleys and free stall alleys were divided by sections of 24 feet long (6 stalls) this will be each manure collection device.

The working area of each device will be W 1 = 24ft x 11ft =264 ft2 free stall alleys

and W 2 = 24 ft x 13.67=328 ft2 feed alleys

Total area of free stall alleys will be W3 =11ft x 300ft = 3300ft2

and feed alleys will be W4 =13.67ft x 300ft = 4101ft2

The total service area of alleys is W = 7401ft2 x2 =14802ft2. With maximum water flushing volume of 53.040liters or 14.013gal with 3-4 discharges a day

The flow rate per square feet will be q= 3.58liter/ft2 or 0.95gal/ft2

The volume of flashing water for each manure collection device:

W 1 = 264ft2 x 3.58liter/ft2 = 945.12 liters or 249.7gal

W 2 = 328ft2 x 3.58liter/ft2 = 1174.24 liters or 310.24 gal.

The flushing devices will work in sequence for about 60 sec automatically.

Water supply piping design should be sized using conventional methods for design water supply piping.(maximum flow rate and velocity around 1.5m/s or 5.0ft/s.)

Drainage piping design should be sized using conventional methods for gravity flow.

( Maximum flow rate and velocity minimum 1.2m/s or 4.0ft/s)

The calculation of water supply and drainage piping for milking parlor and holding area are not included. But about 10-15% of manure is collected at these areas and need to be flushed several times a day [11]. More the milking centre is spending some water and produce wastewater. All data should be included in the design.

Developed method of calculation permitted to design efficient and reliable piping for water supply and drainage systems and manure collection fixtures, which will convey wastewater to the sump.

Free stall Barn Modular Floor Plan Design

The conventional free stall design configurations are two, three, four and six rows of stalls along feed alley. This design assumed, that manure would be moved along allies by mechanical device or flushed with water to a gutter. The development of new manure collection and removal system permits design the dairy barn layout for convenient cow movement, access to feed and water, free stall, and the milking center. Recommended barn modules illustrated on Figure 3.

Modern Dairy Cow Housing Design Manure Management Technology - Image 2

Characteristics of free stall housing module layout

Easy manure collection and removal
One rout between resting and feeding area.
Significantly improves environment inside and outside the barn with much less volume of ventilation.
Convenient feeding with feed space 1.79 ft per stall.
Convenient watering location.
Good cow traffic with minimum cow travel distance.
Cows can be grouped and isolated easily.
Two separate routs between feeding and milking areas.
Module size is 25x120 ft for 28 cows or 107.17ft2/cow. ( 9 m2/cow)
Easy expansion from either end.
Reduced construction and maintenance cost.
The ability to control manure removal permits proper water use and much less volume of wastewater produced with moisture content of 92-95 %.
This is the most important factor in selection of manure treatment and utilization processes.

The proposed modular design has many advantages: in design and construction, it allows to build the barn by stages and easy to expand. It would be highly recommended using for design precast concrete. The Precast/Prestressed concrete floor slab should be build to special specification for cow-friendly floors with distance to ground.

One of important advantage of the design is -excluding moving manure along alley.

This will prevent spreading of diseases through manure.

References:

A.l. Itkin. Manure management, odor and disease control. WEF Animal Residuals 2002 Conference and Workshop, May 6-8 2002 Washington, DC

[1] ASAE D384.2 Mar 2005 Manure Production and Characteristics

[2] MWPS 18-1 Manure Characteristics

[3] C.D. Fulhage, D. Pfost. Basic Requirements for Flushing Dairies. 1993

[4] J.C. Barker, L.B. Driggers, R.E. Sneed. Design Criteria for Swine Waste Flushing Systems. EBAE 080-81 1996

[5] The University of Tennessee. 300-Cow Free Stall and Feeding Facility. Plan No T4158

[6] R.E. Graves. Design Information for Housing Special Dairy Cow ASEBE 064034, 2006

[7] N.B. Cook The Influence of Barn Design on Dairy Cow Hygiene, Lameness and Udder Health.

[8] D.R. Bray, R.A. Buklin. Water Budgets for Florida Dairy Farms