METHOD AND SYSTEM FOR PREPARATION AND DELIVERY OF NUTRIENT SOLUTION IN HOTHOUSE Russian patent published in 1995 - IPC

FIELD: agriculture. SUBSTANCE: system comprises a container for nutrient solution, a system of solution delivery and drainage pipes connected with said container, containers for ingredients of nutrient solution, transmitters, metering pumps. The system also comprises two additional containers. The inlet of the first additional container is connected with the containers for the ingredients of the nutrient solution while its outlet, with the container for nutrient solution. The second additional container is connected with the outlet of the first container and with the system of pipes for delivery and drainage of nutrient solution parallel with the container for nutrient solution. The containers for the ingredients of nutrient solution have transmitters of upper and lower levels. At least some of said containers are provided with heat exchangers for hot and cold heat carriers, and temperature transmitters. The method for the preparation and delivery of nutrient solution involves delivery of solution components into the solution container, indication of temperature, concentration and acidity of nutrient solution, and correction of its composition. According to the invention, ingredients of the nutrient solution are prepared in corresponding containers, temperature is controlled at least in some of said containers by passing hot or cold heat carrier into heat exchangers. Then warm water is filled to a certain level into the first additional container together with the ingredients of the nutrient solution from the corresponding containers. Concentration and/or acidity of nutrient solution is brought to the required value by delivering the solution ingredients or warm water into the first additional container. Simultaneously, the concentration and/or acidity of the solution are brought to the required value by delivering solution ingredients into the first additional container, or warm water into the solution container. The second additional container is filled with warm water then said water is delivered into a hydroponic installation on completion of the photoperiod and the solution supply is cut off. Said cycle is repeated after recommencing of the photoperiod of plants. EFFECT: higher accuracy of metering the components of nutrient solution, elimination of soil salting in operation of the system, and possibility of replacing the spent solution on the running system. 12 cl, 1 dwg