Design Of Wet Curtain-refrigerator Linkage System Based On Industrialized Cultivation Of Edible Fungi

The temperature and humidity in the environment directly affect the growth cycle,overall yield and quality of edible mushrooms.In summer,the temperature in the southern part of China can reach above 35 °C,exceeding the temperature range required for most edible fungi cultivation.Cooling facilities commonly used in mushroom houses include wet curtains and refrigerators.The refrigerator has a fast cooling efficiency and an accurate temperature control,but it is easy to dry the air.The wet curtain reduces the temperature of the mushroom room and humidifies at the same time,and the energy saving effect is remarkable.The main reason for limiting the widespread use of wet curtains in the cultivation of edible fungi is the limited refrigeration capacity,the vulnerability to external environment,and uneven temperature reduction.In this study,the wet curtain was structurally modified to improve its performance in the mushroom house.The fan and the wet curtain are connected by a ventilator to be installed at the top position in the middle of the mushroom house.The external air is blown into the ventilator by the fan,cooled and humidified by the wet curtain,and circulated in the mushroom room from top to bottom.A refrigerator is installed in front of the fan to realize the switching between the wet curtain cooling mode and the wet curtain-refrigerator combined cooling mode.According to the cooling and ventilation operation mode of the equipment,the Delta DVP30EX2 PLC is selected as the core controller,and the software and hardware design of each function module for detection input,arithmetic control and instruction execution is completed.According to the area of the mushroom house and the cooling range,the UDDD15.2/80 air cooler is selected as the main electrical appliance for the wet curtain-refrigerator system,and the types of appliances such as compressors,pumps and electric shutters are selected.After the automatic modification of the wet curtain-refrigerator system,the cooling mode and the ventilation cycle mode can be intelligently switched according to the temperature and humidity control requirements.The single factor transformation method was used to determine the effects of ventilation mode,circulating water flow and temperature on the cooling effect of the equipment.After testing,it was found that:(1)Wet curtain-refrigerator equipment controls the air circulation of the mushroom house,the temperature fluctuation is less than 1.5 °C,and the relative humidity changes less than 5%.(2)The lower the temperature of the wet curtain circulating water,the greater the temperature drop in the room.When the temperature of the wet curtain circulating water is 21 °C,the temperature of the mushroom room is reduced to 23.1 °C.(3)When the circulating water flow rate is 4.2 t/h,the wet curtain paper is sufficiently wetted to ensure the heat absorption effect of evaporation and heat transfer.The Pleurotus diamor mushroom and the P.citrinipileatus mushroom were cultivated in the wet curtain cooling mode,and the difference in the growth of the refrigerator house was compared.The wet curtain increases the air humidity and fluidity,which increases the yield of P.diamor mushroom and P.citrinipileatus mushroom by about 40%,shortens the production cycle by 1-2 days,and saves about 35% of electricity.P.ostreatus and Hericium erinaceus are cultivated in the wet curtain-refrigerator combined cooling mode.Compared with the growth of the mushroom house in the refrigerator,P.ostreatus increased production by 20.1%,H.erinaceus increased yield by 59.16%,and the probability of cauliflower-like fruiting body decreased in H.erinaceus.The transformation of the wet curtain-refrigerator cooling system initially achieved the purpose of controlling the environmental conditions of the mushroom house,saving energy consumption and improving economic benefits.