Maintenance-free fresh air conditioner
Technical Field
A maintenance-free fresh air conditioner. The air conditioner in the technical term of the present generation is a convention name, and the traditional meaning of the air conditioner refers to a machine which is only used for adjusting indoor temperature and humidity, and strictly speaking, the technical field of the air conditioner belongs to a temperature and humidity adjusting machine. Recently, a fresh air machine and an indoor air cleaner are combined with a conventional "air conditioner" to increase a function of adjusting air quality, so that the conventional "air conditioner" concept is endowed with a new meaning, and a new technical field is formed. The invention belongs to the technical field of a full-function air conditioner with an air quality control function on the basis of a temperature and humidity adjusting function.
Background
The essence of the fresh air conditioner is that the introduction of fresh air is increased on the basis of only having a device for adjusting the indoor temperature and humidity. Many attempts and products have been made before, for example, some air conditioner manufacturers add a small air pump and a thin tube to the outside of the room to send the outdoor air into the room without any filtering device, but the initial working effect of this type is still good, but after one year, the dust in the air is deposited on the fins in large quantity, and is carried to the drain pipe by the condensed water, and the dust is deposited to block the drain pipe, so that the whole machine is damaged. Another professional air conditioner manufacturer adds an electrostatic dust collector in an outdoor unit, and the electrostatic dust collector is connected with an indoor unit through a pipeline to supply fresh air to the indoor unit. More attempts have been made to filter dust from the outside air using high efficiency filters (HAPE) before sending into the room, such as: patents CN201821119990 and CN201810732391, however, because the dust holding capacity of the filter material is very small, and the filter material cannot work under a humid condition, the filter element must be frequently replaced or cleaned, which adds much cost and trouble to users, and the product cannot be well popularized.
The key technical requirements of the fresh air conditioner are as follows 3 points: 1. high-efficiency filtration of the outside air; 2. the filter element can reach the standard and stably operate in the environment with high humidity, high dust and high oil smoke; 3. little or no maintenance of the filter element; no product and related information has been retrieved so far that can achieve these three levels of technology simultaneously.
In order to solve the problems, the patent application CN201520577283 of guoshua proposes a technical scheme of using hollow fiber membranes, particularly polytetrafluoroethylene hollow fiber membranes and components thereof, as a main filter material of a fresh air conditioner, and experiments of several years prove that the scheme can satisfactorily achieve the first 2 of the above 3 technical points, but still does not meet the technical requirement of long-term maintenance-free.
Disclosure of Invention
The invention aims to provide further improvement on the basis of the content of the patent application CN201520577283 so as to meet the technical requirement of long-term maintenance-free.
The essence of the invention lies in: a maintenance-free fresh air conditioner is characterized in that a filter element serving as a main filter material is arranged in an outdoor unit case of the air conditioner, a gas collecting hood is arranged at the end part of the filter element, an air outlet valve is connected to the gas collecting hood, the other end of the air outlet valve is connected with an inlet of a low-pressure air pump, an outlet of the low-pressure air pump is connected with a silencer, an outlet of the silencer is connected with an air outlet terminal, and the air outlet terminal is connected with an indoor unit through a pipeline; the gas collecting hood is connected with a high-pressure valve through a thin tube, the other end of the high-pressure valve is connected with a gas storage tank through a thin tube, and the gas storage tank is connected with a high-pressure air pump; a low-pressure sensor is arranged on the gas-collecting hood; a high-pressure sensor is arranged on the gas storage tank; a conventional refrigerating and heating system is also arranged in an outdoor unit case of the air conditioner; when the device is in a fresh air supply working condition, the negative pressure generated by the low-pressure air pump sucks external air into the case, the external air passes through the filter element wall to filter dust, and clean air passes through the air collecting hood, passes through the air outlet valve in an open state, passes through the silencer, and is sent to the indoor unit through the air outlet terminal and the connected pipeline; meanwhile, the high-pressure air pump is pneumatic, the air storage tank is inflated, and when the pressure sensed by the high-pressure sensor reaches 0.2-0.4 Mpa, the high-pressure air pump stops running and enters a pressure maintaining state; when the device is in an air supply working condition, when the low-pressure sensor senses that the pressure reaches 600-1.5 kpa, the air pump stops working, the air outlet valve is closed, the high-pressure air valve is opened, and high-pressure air is flushed into the air collecting hood and the inner cavity of the filter element to generate back-blowing force and remove dust attached to the outer surface of the filter element; the blown dust falls into a dust storage box, and all actions are managed by a control circuit board.
The filter element as the main filter material is a membrane component formed by bundling hollow fiber membrane filaments or a filter cylinder formed by laminating and folding.
The membrane assembly formed by bundling the hollow fiber membrane filaments is polytetrafluoroethylene hollow fiber membrane filaments.
The polytetrafluoroethylene hollow fiber membrane filaments are preferably hydrophilic polytetrafluoroethylene hollow fiber membrane filaments.
For fresh air volume less than 20-100 m/h, a single hollow fiber membrane wire assembly is adopted, and a heating exchanger is not attached between the outdoor unit and the indoor unit; for fresh air volume of less than 100m year/h, a heat exchanger is additionally arranged between the outdoor unit and the indoor unit by adopting an array or curtain type membrane assembly consisting of a plurality of hollow fiber membrane wire assemblies.
Drawings
FIG. 1 is a schematic diagram of an example of a maintenance-free fresh air conditioner using a hollow fiber membrane filter element.
In the figure: (01) a dust storage box; (1) an air outlet terminal; (2) a muffler; (3) a high pressure air pump; (4) a gas storage tank; (5) a high pressure gas valve; (6) a filter element; (7) a gas-collecting hood; (8) a low pressure sensor; (9) an air outlet valve; (10) a low pressure air pump; (11) a control circuit board; (12) outdoor machine case of air conditioner; (13) a high pressure sensor; (14) a cooling and heating part of the air conditioner.
Detailed Description
Valve optimization: as an implementation and optimization, the functions of the two valves of the air outlet valve (9) and the high-pressure air valve (5) can be integrated into a two-position three-way air valve.
Heat exchange: an experimental prototype of the device is designed for a bedroom with a small area of 20 square meters, and the design air volume is 20-50 m for each h, so that the requirement for two persons to breathe can be met. Considering that the air volume is small, if a heat exchanger is additionally arranged, the energy cannot be obviously saved, but the energy is increased, and then a direct air supply mode is adopted. When the design air volume is more than 100m for cultivation under high pressure, a heat exchanger is additionally arranged.
Fresh air effect: in a 15 square meter bedroom for two persons, actual measurement data are continuously measured for several months, and the indoor carbon dioxide concentration rises to 4500ppm after 9 hours under the condition that only refrigeration is carried out without adding fresh air. Fresh air supply is opened, and the concentration of carbon dioxide in the room is lower than 1000PPm after 9 hours. The filtration effect is always kept at a PM 2.5-1 ug/m flowering level.
The back flushing effect is as follows: a group of polytetrafluoroethylene hollow fiber membrane experimental membrane filaments with specific models are arranged on a test bed. Under the condition of no back flushing, after 2Kg of test powder is sucked, the pressure of the filter element is increased from 380Pa to 2000Pa to-3000 Pa. And back flushing is increased, after 2kg of test powder is sucked, the pressure of the filter element is increased to 520Pa from 380Pa, then 8kg of test powder is sucked, and the wind resistance pressure of the filter element is fluctuated between 400 and 520Pa all the time. The filtration effect is always kept at a PM 2.5-1 ug/m flowering level.
And (3) verifying high humidity resistance: and (3) producing steam by using an electric heating kettle, evaporating 1800ml in 20 minutes, and directly sucking 500 g of test powder into an air inlet of the membrane component when the air volume of the fresh air fan is 50 m/h. The filter element windage pressure always fluctuates between 500 and 620 pa. The filtration effect is always kept at a PM 2.5-1 ug/m flowering level.
A dust storage box: taking 50m for example, in an atmospheric environment with an average of 100ug/m for year-averaged harvest (50 ug/m for 2018 in Beijing), 40 g of dust is collected every year, and if the design capacity of the dust storage box is 1Kg, the dust storage box can be used without cleaning for 25 years.
Advantageous effects
1. The maintenance-free air conditioner has the advantages that the maintenance-free air conditioner is free of materials for a long time, the maintenance cost is greatly saved, and conditions are created for the practicability of the fresh air conditioner.
2. Can stably work for a long time under the conditions of high humidity, dewing and even partial water immersion, which can not be achieved by the traditional HAPE and electrostatic dust collector.
3. High filtering precision, low energy consumption, no ozone hazard, convenient installation, low noise, convenient recycling of filter materials, high value and no secondary pollution.