![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
1, Foreword The heat pump as a heat source for drying, drying and dehydration and other operations, is the 1980s developed a new type of drying technology. At present, the technology has been applied in various fields, such as wood, chemical products, food drying, vegetable dehydration and sludge stool drying, etc., have achieved good results. For sludge and excrement drying problems, heat pump drying technology with low operating costs and environmental pollution without any two major advantages. As early as the early eighties of last century Japan has been successfully used. 2, the principle of heat pump heat pump heat pump drying equipment by the heat cycle and hot air drying system composed of circulation. Heat pump circulation system for hot air drying system to provide heat and reduce hot air humidity. Hot air drying system, direct contact with the material through the hot air circulation, to provide heat evaporation moisture, take away the moisture in the material. The so-called "heat pump" is a kind of energy-saving device which consumes a certain amount of mechanical work and absorbs the low-grade heat energy in the environment or wastes to increase it into usable heat energy. Just like a "water pump", it takes a certain amount of mechanical work to raise the water from a low water level to a desired water level. The heat pump system consists of compressor, condenser, throttling device and evaporator. The working medium in the system absorbs the heat from the drying chamber to discharge the hot and humid air in the evaporator and evaporates into low pressure steam from the low pressure liquid refrigerant and becomes the high temperature and high pressure steam after being pressurized by the compressor; in the condenser, the high temperature and pressure The working fluid heat releases heat to enter the air in the drying chamber, while the working fluid itself condenses from the gas to a high pressure liquid. Through the throttling device, the liquid working fluid produces a blocking effect, reducing the pressure and temperature, becoming a low pressure and cryogenic liquid and re-entering the evaporation Absorption of hot and humid heat in the gas, so repeatedly circulating the low temperature heat transfer to the high temperature medium to form a heat pump cycle. Drying chamber exhaust gas is a high moisture content of hot and humid gas, the state shown in Figure hd point a, its relative humidity ψ = 70 ~ 80% or so, through the heat pump evaporator, the evaporator surface The temperature below the dew point of the air not only reduces the temperature of the air but also condenses the water vapor on the evaporator surface and exits the system as liquid water. The gas leaves the evaporator to become cold and wet, as shown in Figure 1. The relative humidity is generally ψ = 95-97%. After desorption of gas in the heat pump condenser to get wet heating, increased gas temperature, but also reduces the relative humidity, as shown in a point C into a hot dry gas into the drying chamber. In the drying chamber, the dry hot gas is in direct contact with the material being dried, providing the heat of the material to dry, while also removing moisture. Air in the drying chamber isenthalpic humidification cooling process, when leaving the drying chamber and returned to a point a. As can be seen from Figure 1 per kilogram of gas through a cycle of water can be removed △ d = da-dc. Figure 1: Schematic diagram of heat pump hot air circulation on hd From the above principles of heat pump drying point of view, the difference with the general drying process is no hot and humid gas emissions, through two closed loop system, the water in the material eventually to liquid water to exclude. The principle of sludge drying has two major advantages: (1) energy conservation: in the heat pump drying. Do not discharge hot and humid gas and its sensible heat and latent heat all recovered, only spent a certain amount of mechanical work. Commonly used to measure the heat pump heat recovery capacity of the commonly used performance coefficient of the heat pump to characterize that the COP = condenser to provide heat / compressor power = QC / W0 in the sludge drying equipment COP = 4.0 ~ 5.0, both the heat pump heat is power consumption 4 to 5 times the heat. Measurement of drying equipment consumption Another important indicator Heat pump than the dehydration rate WPE WPE = dehydration / heat pump energy = kg (water) / kw.H (electricity) in the current equipment heat pump WPE = 5.0 ~ 6.0. That can be dehydrated per kilogram of 5 to 6 kg. (2) do not pollute the environment: As the heat pump dry sludge in a closed environment, all the stink and harmful gases generated in the drying process can be done without leakage, the surrounding environment can be reduced to a minimum of pollution, favorable Drying is done near the settlements. 3, heat pump dry sludge device profile I have scientific and technical personnel since the eighties, heat pump drying technology conducted a systematic research and development. A series of high-temperature heat pump dehumidifiers have been developed using a high-temperature thermal performance refrigerant R142b and a unique hot-air circulation system (patent number: ZL.4). The unit's drying temperature in the 50 ~ 85 ℃ range can work, so far have been 500 to 600 sets (sets) of equipment put into operation, especially in wood drying has achieved excellent results; such as Shanghai's high-quality wood products more than half, I use my equipment for drying. Export brand-name wood products, almost all of my equipment for drying process. In 2000 won the "national key new product" title, since 1997 I was named "high-tech enterprises in Shanghai." The drying chamber matching the heat pump drying unit has two modes: continuous drying and intermittent drying. The general material is relatively coarse, the drying cycle is longer or the material does not form batch batch drying, that is, the material is loaded and unloaded intermittently. Such as wood, agricultural and sideline products, herbs, handicrafts and more in this way. Figure 2: sludge drying device for the sludge drying cycle is relatively short, bulk and larger, small and granular material after forming a more uniform and therefore should adopt continuous feeding and discharging continuous drying. A prototype of a sludge drying continuous heat pump drying device developed by our company is shown in Fig. 2, and its appearance is shown in the photo 1. Heat pump dryer is still using my fruitful, mature unit. Drying room equipped with adjustable speed stainless steel belt conveyor belt group. In order to dry the process all in a closed environment, in the drying chamber equipped with two sets of molding machines. Sludge dry continuous heat pump drying device after fermentation, the water content of 60 to 65% of the powdery sludge through the closed conveyor, into the drying chamber, in order to facilitate drying, to prevent the sludge drying after drying, through the initial molding, Pouring the conveyor belt, the conveyor belt at a set speed with the material transport, transport back and forth through the number of layers of the conveyor belt so that the sludge drying to about 40% moisture content before the second molding into a granular fertilizer, and then transported back and forth by several conveyor belt dry , And finally reach the 20% moisture content of the finished fertilizer (see photo 2) out of the drying chamber, and then sent to the closure of the packaging machine through the packaging plant, Sheng bag out. & nbsp