High efficiency tidal irrigation system for flower seedlings in greenhouse to understand the relationship between flower planting and meteorological conditions.

I. Overview of tidal irrigation system

Tidal irrigation system is an efficient water-saving irrigation system based on the principle of tidal fluctuation. It is suitable for the planting and management of all kinds of potted plants and can effectively improve the utilization efficiency of water resources and nutrient solution. Tidal irrigation is mainly divided into two types, surface type and bed planting type. The surface tidal irrigation system is to build a seedling tray filling pool that can store water on the surface, in which a number of outlet holes and backwater holes are distributed, while the planting bed tidal irrigation system builds a large area water storage seedling tray on the seedling bed, leaving water outlet and return holes on the seedling plate. In application, irrigation water or well-proportioned nutrient solution overflows from the outlet hole, so that the water level in the whole seedling bed rises slowly and reaches a suitable liquid level height (called high tide), and the cultivation bed is submerged at a depth of about 2-3 cm. After keeping it for a certain period of time (crop roots are fully absorbed), after about 10-15 minutes, the nutrient solution rises to the surface of the medium in the basin due to capillarity. at this time, open the backwater outlet, discharge the nutrient solution, and return to the nutrient solution pool (called ebb tide). When another cultivation bed needs water, the nutrient solution will be sent out. The tidal irrigation system has the equipment to adjust the pH value and various nutrient concentrations of the nutrient solution, and to increase the filtration system and disinfection system to avoid excessive contamination of the nutrient solution. Planting bed tidal irrigation systems all need to use high-rise special cultivation beds, so the corresponding equipment costs are also higher.

II. Excellent characteristics of tidal irrigation system

Tidal irrigation is a mature agricultural irrigation technology, which has been widely used in developed countries, which well solves the contradiction between irrigation and oxygen supply, and irrigation basically does not destroy the "three-phase" composition of the matrix, so it is an efficient and high-energy agricultural technology. it is also in the development stage of extensive use in our country.

1. Water-saving and efficient, completely closed system cycle, which can achieve 90% utilization.

2. the plant growth rate is faster, and the seedling age per week can be one day earlier than the traditional seedling raising method, so as to improve the utilization rate of the facility.

3. Avoid the formation of water film on the leaves of plants, make the leaves accept more light for photosynthesis, and promote transpiration pull to absorb more nutrients from the roots.

4. Stable moisture content in the root medium to prevent the capillary root from dying due to drought near the edge and bottom of the container.

5. the relative humidity is easy to control, keep the leaf surface dry and reduce the use of chemical drugs.

6. there is no weed growth under the planting bed, which reduces the growth of fungi, because it is very dry under the planting bed.

7. The management cost is reduced. Whether it is operated manually or managed by a microcomputer controller, a person can complete 0.2~0.5ha within 20-30min. Irrigation of burrow-tray seedlings

8. It can be used at any time, regardless of variety, specification and time limit.

9. The general sprinkler irrigation method makes each plant absorb fertilizer and water unevenly, resulting in a decrease in the rate of finished products, while the rate of finished products under tidal irrigation is 100%, and the production is standardized, each plant is highly unified, and the quality is guaranteed.

10. Tidal irrigation absorbs fertilizer directly from the root. The water does not touch the leaf surface, and the leaf surface is shiny, which makes the selling price even higher. Based on the production of 25 pots per square meter, if the quality is improved, each pot can be sold for an extra 5 to 10 yuan. The income per square meter is increased by as much as 125 to 250 yuan, and the return on investment is considerable.

III. Description of tidal irrigation system

High tide: there are conveying pipes on both sides of each planting bed, and a water pump is set at the front end of the pipe. The automatic irrigation controller controls the nutrient solution to be sent from the fertilization system to the planting bed. Ensure that the high tide will be completed within a certain period of time.

Low tide: when the high tide pump stops working, after the plant is irrigated, the automatic irrigation controller controls the return pump to start and send the nutrient liquid back to the liquid tank.

IV. Configuration of tidal irrigation system

The configuration of tidal irrigation system is divided into surface planting bed irrigation system configuration and seedbed irrigation system configuration. The surface planting bed irrigation system is suitable for the planting of larger plants, and the seedbed irrigation system is suitable for the planting of smaller plants.

Design of Surface Irrigation planting bed

The planting bed shall be built according to the size of the greenhouse and the requirements of the owner. Water troughs with different depths are built on the planting bed in the north-south and east-west directions. At high tide, the deep trenches in the north-south direction distribute the incoming water to the planting bed. Due to the rising water level, the east-west shallow trough sends water to the bottom of the flowerpot, and the water inlet of the water source is provided with a splash-proof device cover. The water on the planting bed reaches the bottom of the flowerpot at about the same time. At low tide, the water from the flowerpot collects directly into the north-south deep trough through the east-west shallow trough, and then sends the excess liquid back to the return tank.

Design of seedbed irrigation system

There is a nutrient liquid supply box under the end of each planting bed, and a submersible pump is set up in the box to send the nutrient liquid from the box to the planting bed through the liquid delivery pipe, the flow rate of the pump should be guaranteed to complete the high tide within a certain period of time. The top of the liquid delivery pipe is provided with a cushioning device to avoid spraying the leaves of the plant. When the pump stops working, the remaining liquid is returned to the tank through the same pipe and pump, so that the same pipe can be used for irrigation and recovery.

The configuration of the seedbed tidal irrigation system is basically the same as that of the surface tidal irrigation system, except that the tidal inlet drainage tray on the bed is different from the surface tidal irrigation system.

The irrigation plan can be transmitted from the matrix tensiometer on each planting bed to the environment control computer in the greenhouse, and the computer controls the water pump through the controller. When the computer receives less than the set tension value, the program starts the pump to work, and the working time is a fixed value. The matrix humidity tensiometer consists of a high-flow ceramic tip with a sensitive pressure sensor controlled by a computer environment. The tensiometer will respond to the change of humidity tension in the matrix in an instant.

1. Fertiliser system setup

The fertilizing machine contains four nutrient tanks, one acid tank and one mixing tank.

It mainly consists of the following four parts.

① according to the nutritional ratio from the feeding tank to the mixing tank injection pump and three-way flow valve.

② is a mixing tank that combines water, nutrition and acid at atmospheric pressure.

③ transports the liquid from the mixing tank to the main pump in the irrigation area.

The hardware integration board of ④ fertilizing machine consists of EC value, pH value and flow rate input, acid pump, nutrition pump, solenoid valve and main pump output port.

2. Computer control system

The fertilizer machine can continuously provide water and nutrient solution to plants according to the optimal growth conditions of plants. The fertilizer machine has five separate fertilizer injectors, which are controlled by the same environment control computer in the greenhouse. The water flow and the nutrition ratio of each valve are controlled by the software program. The whole system is composed of software, hardware, transmission equipment, sensors, environmental control, irrigation control and nutrition control.

3. System operation

The fertilizing machine can accurately feed liquid from the feeding tank to the mixing tank through the solenoid three-way valve. according to the requirement of nutrition ratio, the solenoid valve can supply liquid to the mixing tank or return to the original tank.

The computer can monitor and alarm the pH value and EC value of the liquid flowing out of the mixing tank and adjust the flow rate. The mixture ratio can be set in advance by the grower, this kind of monitoring is only to ensure the normal operation of the system, not a timely control. Due to the failure of the system or the ratio sensor, when the ratio of the mixture exceeds the set limit, the system will alarm and take necessary measures.

Due to the different number of valves opened for irrigation, when the output flow of the system changes, the computer automatically controls the feeding amount of the nutrient solution through the solenoid valve to ensure the set ratio and flow.

Configuration description of main equipment

1) automatic irrigation and fertilization unit

The automatic irrigation and fertilization unit is controlled by the controller. it is specially developed for the greenhouse horticulture industry. it is a proven stable and reliable controller. If the control panel is installed on the irrigation unit, the control of the irrigation unit can be realized. The opening and closing of the solenoid valve can be controlled by preset start-up conditions so as to control the progress of irrigation and fertilization. Start-up conditions can be set with time, light intensity, cumulative light and external control conditions. The machine can accurately control EC and pH value, so each crop will receive a strict quota of fertilizer. In long-term practice, growers can easily and more grasp the information about the amount of water and fertilizer used for this crop, so as to cultivate more high-quality products.

The components used in the automatic irrigation and fertilization system are tested high-quality originals to ensure that they can run well. It can be used alone to realize the control of irrigation and fertilization in the greenhouse, and it can also be used in combination with other automatic control equipment in the greenhouse to realize the overall automatic control in the greenhouse. As an additional service, we can design the most ideal overall irrigation and fertilization system for users according to their specific needs.

The fully automatic irrigation and fertilization control system brings a variety of benefits to customers:

-efficient fertilization for all crops

-Saving expensive fertilizer and water consumption

-accurate, stable and reliable

-simple stainless steel rack, flexible and diverse choice

-can use "independent" irrigation units or form a complete greenhouse control scheme

-recordable irrigation and fertilization data

-cost-effective

System configuration:

Stainless steel rack: outer package size is 1.68mx1.40mx1.15m (hxlxb)

Mixing tank system: the volume of mixing tank is 0.2m3

Water pump: under the pressure of 3.5bar, the water output per hour can reach 12m3, 10m3 or 40m3.

Float Flowmeter (one on each feed pipe)

2 EC and pH sensors

Electronic interface design conforms to international standards

Electronic Flowmeter

1x130Micron filter

3 readable pressure gauges

2) computer irrigation control:

White cabinet box, 8 buttons

Operate through common symbols

Menu display (no need to remember any code / code)

The monitor can display 2 lines of letters, each with 40 characters

40 output signals control external equipment

20 input signals are connected to various sensors

Can record and report irrigation data, and view historical data

Automatic background light display function

Accurate, stable and reliable EC/pH control

Up to 8 feed pipes can be controlled

Ten starting conditions control the opening and stopping of solenoid valves

Opening control of each solenoid valve, one cycle every 24 hours

Chinese operation interface

3) the disinfection system has two kinds of ultraviolet disinfector and ozone disinfector, either of which is optional.

Ultraviolet disinfector

The ultraviolet disinfector makes use of the strong killing effect of ultraviolet light with wavelength 225nm-275nm on microorganisms to kill the microorganisms in the raw water.

Product characteristics

The sterilization speed is fast, does not change the physical and chemical properties of water, does not increase the smell of water, does not produce halogenated methane compounds that are harmful to human body, and has no side effects.

The water treatment cylinder adopts imported high-quality stainless steel, which can meet the working pressure of 1.2MPa, and has the advantages of anti-rust, high strength, no metal ion pollution, easy cleaning of equipment surface and so on.

The ultraviolet lamp selects the professional new product identified by the national health department and the epidemic prevention department, the power is 30W, the main line spectrum 253.7nm, this wavelength ultraviolet sterilization rate is the highest, can reach 98% above, the energy consumption is low, the continuous service life can reach more than 3000 hours, and is equipped with reliable ballast equipment.

The modular electric control device has complete functions, timing standard, and integrated design with water treatment cylinder, which has the characteristics of convenient installation, simple operation, safety and reliability, and easy maintenance.

Ozone disinfector

1 ozone disinfector

Ozone production: 5g/h Product size: 350*250*580mm (length * width * height)

Ozone concentration: air source 5-20g/m3 oxygen source 20-35g/m3

Cooling method: air-cooled power supply: 220V/50Hz

Power: 160W (power is adjusted according to actual needs)

Air source type: air source and oxygen source dual-purpose type, built-in oil-free air compressor, air compressor independent control switch

Product configuration: dehydroxy quartz structure ozone generator unit, all stainless steel chassis, precision ammeter, fan, with ozone regulator (knob type), etc.