阅读说明：本技术 一种移动式干冰缓释预冷荔枝保鲜装置 (Movable type dry ice slow-release precooling litchi fresh-keeping device ) 是由 卓献荣 陈嘉澍 陈学彬 于 2020-05-09 设计创作，主要内容包括：本发明涉及果蔬气调冷藏保鲜装置技术领域,具体涉及一种移动式干冰缓释预冷荔枝保鲜装置,包括用于放置荔枝或者其他果蔬的预冷腔、用于制冷的干冰缓释制冷腔。其中,设置在干冰缓释制冷腔内的干冰升华换热系统包括进风口、贮藏腔、干冰升华换热篮、出风口,所述的干冰升华换热篮为干冰连续地进行升华换热的场所,其可拆卸地放置在贮藏腔中,所述的进风口及出风口分别开设在贮藏腔的腔壁上。本发明有效解决荔枝采摘后的田间预冷问题,有降温、灭菌、避免冻伤与不洁水污染果实多个优势,从而在荔枝保鲜冷链的第一环节上实现最大程度的保鲜。(The invention relates to the technical field of fruit and vegetable air-conditioning refrigeration preservation devices, in particular to a mobile dry ice slow-release precooling litchi preservation device which comprises a precooling cavity for placing litchi or other fruits and vegetables and a dry ice slow-release refrigerating cavity for refrigerating. The dry ice sublimation heat exchange system arranged in the dry ice slow-release refrigeration cavity comprises an air inlet, a storage cavity, a dry ice sublimation heat exchange basket and an air outlet, wherein the dry ice sublimation heat exchange basket is a place where dry ice continuously sublimes for heat exchange, the dry ice sublimation heat exchange basket is detachably arranged in the storage cavity, and the air inlet and the air outlet are respectively arranged on the wall of the storage cavity. The invention effectively solves the problem of field precooling after litchi picking, and has the advantages of cooling, sterilizing, avoiding frostbite and dirty water pollution to fruits, thereby realizing the maximum fresh-keeping on the first link of the litchi fresh-keeping cold chain.)

1. A mobile dry ice slow-release precooling litchi fresh-keeping device comprises a dry ice slow-release pre-freezer, wherein the interior of the dry ice slow-release pre-freezer comprises a pre-cooling cavity and a refrigerating cavity, and the dry ice slow-release refrigerating cavity is provided with a dry ice sublimation heat exchange system; the dry ice sublimation heat exchange system is characterized by comprising an air inlet, a storage cavity, a dry ice sublimation heat exchange basket and an air outlet; the dry ice sublimation heat exchange basket is detachably arranged in the storage cavity, and the air inlet and the air outlet are respectively arranged on the wall of the storage cavity.

2. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 1, wherein a basket bottom of the dry ice sublimation heat exchange basket is a heat exchange sieve plate with sieve holes, the heat exchange sieve plate is an arc-shaped sieve plate or a sawtooth-shaped sieve plate, and a plurality of gas flow channels are formed in the bottom surface.

3. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 2, wherein the air supply system comprises an air supply slow-release cavity, an air supply filler grid, an air outlet buffer cavity and an air supply unit; the air supply slow release cavity is characterized in that an air outlet is formed in the cavity wall of one side of the air supply slow release cavity, an air supply filler grid is arranged on the cavity wall of the other side of the air supply slow release cavity, spongy filler is filled in the cavity, the air outlet buffer cavity is connected with the air supply filler grid, an air supply unit is arranged in the cavity, and the air outlet buffer cavity is communicated with the precooling cavity.

4. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 3, wherein the return air system comprises a return air slow-release cavity, a return air filler grid, a return air static pressure cavity and a return fan set; the air return slow-release device is characterized in that an air inlet is formed in the cavity wall on one side of the air return slow-release cavity, an air return filler grid is arranged on the cavity wall on the other side of the air return slow-release cavity, spongy filler is filled in the cavity, the air return static pressure cavity is connected with the air return filler grid, a fan return unit is arranged in the cavity, and the air return static pressure cavity is communicated with the precooling.

5. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 4, wherein a blowing grid is arranged between the air-out buffer cavity and the precooling cavity, and a return grid is arranged between the return air static pressure cavity and the precooling cavity.

6. The mobile dry ice slow-release precooling litchi fresh-keeping device according to claim 5, wherein the dry ice sublimation heat exchange system further comprises a slow-release cavity heat insulation plate, and the slow-release cavity heat insulation plate is arranged between the dry ice sublimation heat exchange basket and the cabinet body.

7. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 6, wherein the air supply unit and the air return unit are provided with an air return temperature controller.

8. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claims 1 to 7, wherein a small pressure difference exhaust valve is arranged on an opening of a box body of the precooling cavity.

9. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 8, wherein the dry ice slow-release refrigeration cavity is provided with a dry ice injection door, and the precooling cavity is provided with a heat preservation door.

10. The mobile dry ice slow-release precooling litchi fresh-keeping device as claimed in claim 9, wherein the plates of the box body of the dry ice slow-release precooling litchi fresh-keeping device are composed of two layers, the outer plate is a composite steel plate or a stainless steel plate, the inner plate is a stainless steel thin plate or other plates meeting the food sanitation requirement, and the cabinet body can be integrally formed by high-pressure foaming and can also be assembled by a prefabricated heat preservation storage plate.

Technical Field

The invention relates to a fruit and vegetable cold storage and preservation device, in particular to a mobile dry ice slow-release precooling litchi preservation device, and belongs to the technical field of fruit and vegetable air-conditioning cold storage and preservation devices.

Background

In order to improve the quality, safety and market value of food, the food fresh-keeping 'cold chain' is paid attention by domestic public. Litchi is widely popular with people at home and abroad as a famous and precious fruit with Lingnan characteristics. Along with the development of litchi preservation technology, the litchi industry is rapidly developed along with the continuous expansion of the market, and in recent years, many areas (such as famous, subordinate and city-increasing) in the south of Ling also become the litchi dominant industrial park.

At present, the litchi fresh-keeping technology mainly comprises two types of physical fresh-keeping and chemical fresh-keeping. Wherein, the physical preservation mainly adopts cooling refrigeration and flexible packaging technology, and the chemical preservation mainly adopts preservative soaking and covering agent wrapping technology. With the continuous improvement of the requirements on the food safety and quality, the physical preservation technology is more accepted by consumers, and the cold chain technology becomes the main development direction of the litchi preservation technology.

The cold chain is provided based on the principle that fruits and vegetables can effectively inhibit bacterial activity and enzyme speed under low-temperature environment so as to achieve fresh-keeping. Generally, the method comprises the steps of picking fruits and vegetables in the field, gathering and processing the production area, storing the processed production area, transporting, storing in wholesale, retailing and using the fruits and vegetables in the cold environment, wherein the cold of each link is buckled with a ring like a chain, so that the links are visually called as the cold chain. Thus, the composition of the "litchi freshness cold chain" typically comprises: 'chain of 7 links' of field precooling of litchi → gathering precooling processing of litchi producing area → refrigerating of litchi producing area after processing → refrigerating transportation of litchi → wholesale refrigerating of litchi → refrigerating retail of litchi → refrigerating of user refrigerator.

With the rapid development of electronic commerce, the direct sale of fresh litchi fruits from the production place to users has become an obvious trend, and the cold chain is named as a litchi electronic commerce type cold chain and comprises the following components: the method comprises the following steps of ' precooling litchi in a field → collecting and precooling litchi producing areas → refrigerating litchi producing areas after litchi processing → refrigerating litchi in a refrigerating express way → refrigerating litchi in a refrigerator of a user ' for a 5-link ' and reduces two links of ' wholesale refrigerating of litchi → refrigerating and retailing of litchi '. When the electronic commerce orders are many, the litchi electronic commerce type cold chain can skip the litchi post-processing production place refrigeration and is changed into the following steps: 'chain of 4 links' of 'litchi field precooling → litchi production area gathering precooling processing → litchi refrigeration express transportation → user refrigerator refrigeration'.

For the litchi electronic commerce type cold chain, as the refrigerators are distributed in thousands of households, the link of → refrigeration of the refrigerators of the users is no longer a problem. Obviously, the main technical improvement needed is three links of litchi field precooling → litchi producing area collecting precooling processing → litchi refrigeration express delivery. The litchi preserving method is limited by factors such as practical conditions and traditional concepts and current litchi preserving technical measures, although people have clearly recognized the key role of the first litchi preserving link, many people still think that the distance between the field and the production place is not long, so that the current situation that the actual duration time of the field and the production place is actually long (more than 10 hours on average) is ignored, and the litchi picked in the field is directly sent to the production place to be converged for pre-cold processing, so that the current popular simplified version of the litchi electronic commerce type cold chain is actually formed: 'litchi producing area gathering precooling processing → litchi refrigeration express transportation → user refrigerator refrigeration'.

Fresh litchi peel is the globular arch of multilayer level, litchi fruit flesh is thick, because summer, the temperature of gas is higher when the litchi is picked, has a large amount of field heats after picking, and the litchi still breathes exuberantly, can continuously release respiratory heat, and a large amount of practices and research results prove that if not cooling in time, the maturity and ageing of litchi fruit can accelerate, and the moisture transpiration of litchi fruit can be strengthened, leads to the fruit moisture to dissipate the increase, and the peel is easily dried and shrunk. On the other hand, the life of various flora on the litchi peel is active, and the litchi peel is easy to brown, even rot and deteriorate. The first link of the litchi fresh-keeping cold chain, namely field precooling → litchi production place convergence precooling processing →, is based on the problems, and aims to eliminate field heat and respiratory heat after litchi picking as soon as possible, namely, to carry out precooling as fast as possible, so that the litchi aging speed is delayed, peel drying and shrinkage are reduced to the maximum extent, and the litchi fresh-keeping cold chain plays a key role, namely, the shelf life is prolonged to the maximum extent, and the good fruit rate is improved.

The prior litchi precooling technology mainly comprises two main types, one type is cold water or ice water precooling, although the technical measure can quickly eliminate the field heat of litchi, the technical measure has the defects that excessive water adhered to the surface of the precooled peel can cause subsequent browning and the like, and the wet percolation appearance is obviously not favorable for sale. The other type is air-cooled precooling, and the litchi fruits are poor in cooling temperature uniformity and low in fruit yield when being air-cooled precooled.

With the development of the e-commerce and express transportation industries, in recent years, under the promotion of the subsidies of governments at all levels, litchi fresh-keeping 'cold chains' are gradually established by many litchi industry leading enterprises, and although the 'cold chains' are rough, the litchi fresh-keeping 'cold chains' still expand the market of fresh litchi food to a certain extent, and the litchi industry is greatly promoted to develop.

In conclusion, the litchi fresh-keeping cold chain is initially established in Guangdong province of the current litchi producing area, and plays an important role in the market development and the industrial development of fresh litchi. However, with the objective requirements of the litchi superior industry and high-quality development, the cold chain not only needs to perfect various links, but also needs to carry out 'fine-and-fine' type optimization on the 'chain' of each link, and breaks through the industrial development limitation from the technical means.

Disclosure of Invention

In order to overcome the defects of the prior art, the litchi fresh-keeping method is based on the contradiction between the high-quality development requirement of the litchi industry and the limitation of the current litchi fresh-keeping technology, and aims to further improve the litchi fresh-keeping quality and prolong the physical fresh-keeping time of litchi, so that the aim of improving the market value to be macroscopic is fulfilled. Technically, the method focuses on the first link of the litchi fresh-keeping cold chain: according to the field precooling problem of picked litchis, according to the peculiar thermal physical properties of large sublimation latent heat of dry ice and sterilization function, the matched dry ice slow-release cooling technology is adopted, so that not only can the temperature be reduced, but also the litchis can be sterilized, the fruit can be prevented from being frozen and polluted by dirty water, the litchi fresh-keeping cold chain technology is comprehensively optimized and innovated, the field heat and the respiratory heat of the litchis can be timely reduced, the ripening and aging speed of the litchis can be delayed, and the water transpiration effect of the litchis can be weakened, meanwhile, the sterilization can be carried out on various types of flora on the litchis can be carried out, so that the maximum fresh-keeping can be realized in the first link of the litchi fresh-keeping cold chain, the optimal basis is laid for the subsequent function of the cold chain.

The purpose of the invention is realized by the following technical scheme:

a movable type dry ice slow-release precooling litchi fresh-keeping device comprises a dry ice slow-release precooling cabinet, wherein the interior of the dry ice slow-release precooling cabinet is partially provided with two cavities, the front part of the cabinet body is provided with a precooling cavity which has the function of precooling collected litchi or other vegetables and fruits needing to be refrigerated and stored, and the rear part of the cabinet body is provided with a dry ice slow-release refrigerating cavity which has the function of refrigerating.

The dry ice slow-release refrigeration cavity is provided with a dry ice sublimation heat exchange system; the dry ice sublimation heat exchange system is characterized by comprising an air inlet, a storage cavity, a dry ice sublimation heat exchange basket and an air outlet; the dry ice sublimation heat exchange basket is a place where dry ice continuously carries out sublimation heat exchange, the dry ice sublimation heat exchange basket is detachably arranged in the storage cavity, and the air inlet and the air outlet are respectively arranged on the wall of the storage cavity.

The bottom of the basket of the dry ice sublimation heat exchange basket is a heat exchange sieve plate with sieve pores, the heat exchange sieve plate is an arc-shaped sieve plate or a sawtooth sieve plate, the arc-shaped surface or the sawtooth surface increases the heat exchange area, the sublimation heat exchange of the dry ice is facilitated, a plurality of gas flow channels are formed in the bottom surface, one end of each flow channel is opposite to the air inlet, the other end of each flow channel is opposite to the air outlet, the flow of dry ice gas is facilitated to be improved, and the refrigerating efficiency is further improved. See through sieve mesh and dry ice contact when heat transfer gas flows through heat transfer sieve bottom from the air intake, at this moment heat transfer gas carries out convection heating and heat conduction heating to sieve and dry ice simultaneously, the dry ice that makes dry ice sublimation heat transfer basket bottom under the combined action takes place the sublimation earlier, then dry ice is constantly filled on basket end heat transfer sieve under the action of gravity in the basket, sublimed dry ice gas passes through the air outlet and flows out, enter into the precooling intracavity through air supply system and cool down the litchi of intracavity, absorbed the thermal gas in precooling intracavity and flow back to the storage intracavity through the air intake under return air system's effect, so circulation is reciprocal, realize the continuous refrigeration to the precooling chamber.

The dry ice slow-release refrigeration cavity is also provided with an air supply system, and the air supply system comprises an air supply slow-release cavity, an air supply filler grid, an air outlet buffer cavity and an air supply unit; the air supply slow release cavity is characterized in that an air outlet is formed in the cavity wall of one side of the air supply slow release cavity, an air supply filler grid is arranged on the cavity wall of the other side of the air supply slow release cavity, spongy filler is filled in the cavity, the air outlet buffer cavity is connected with the air supply filler grid, an air supply unit is arranged in the cavity, and the air outlet buffer cavity is communicated with the precooling cavity. And under the air supply effect of the air supply unit, the low-temperature high-concentration carbon dioxide gas flowing out of the air outlet is sent to the air supply slow release cavity, then enters the air outlet buffer cavity through the air supply filler grating, and finally is sent to the precooling cavity by the air supply unit to cool, precool and sterilize the litchi or other vegetables and fruits, so that the task of the air supply system is completed. When the airflow circulates, the spongy filler in the air supply slow release cavity plays a role in slow release of low-temperature gas, so that the gas flows more uniformly, and the air supply filler grating effectively prevents the spongy filler from moving into the air outlet buffer cavity to influence the normal operation of the air supply unit. When the fruits and vegetables are not placed in the precooling cavity 18, the air supply unit stops operating, the air flow is static, the spongy filler plays a heat preservation role, and the sublimation process of the dry ice is slowed down.

The dry ice slow-release refrigeration cavity is also provided with an air return system, and the air return system comprises an air return slow-release cavity, an air return filler grid, an air return static pressure cavity and an air return machine group; the air return slow-release device is characterized in that an air inlet is formed in the cavity wall on one side of the air return slow-release cavity, an air return filler grid is arranged on the cavity wall on the other side of the air return slow-release cavity, spongy filler is filled in the cavity, the air return static pressure cavity is connected with the air return filler grid, a fan return unit is arranged in the cavity, and the air return static pressure cavity is communicated with the precooling. The precooling cavity cools, precools and sterilizes litchi or other vegetables and fruits to obtain high-temperature low-concentration carbon dioxide gas, the high-temperature low-concentration carbon dioxide gas enters the return air static pressure cavity under the action of return air of the return air fan set, flows to the return air slow release cavity through the return air filler grid and finally blows to the air inlet of the dry ice sublimation heat exchange system to perform sublimation heat exchange with dry ice in the dry ice sublimation heat exchange basket in the storage cavity, and the task of the return air system is completed. During air current circulation, the spongy filler in the return air slow release cavity plays a role in slow release of high-temperature gas, so that the gas flows more uniformly, and the return air filler grille effectively prevents the spongy filler from moving into the return air static pressure cavity to influence the normal operation of the return air fan unit. When the fruits and vegetables are not placed in the precooling cavity, the air return fan set stops operating, the air flow is static, the spongy filler plays a role in heat preservation, and the sublimation process of the dry ice is slowed down.

Wherein, in order to make the gas flowing out of the precooling cavity through the blower set more uniform, a blowing grid is arranged between the air-out buffer cavity and the precooling cavity.

In order to enable the gas flowing into the precooling cavity through the air return fan set to be more uniform, an air return grid is arranged between the air return static pressure cavity and the precooling cavity.

Wherein, still be equipped with a slowly-releasing chamber heat insulating board between dry ice sublimation heat transfer basket and the cabinet body for reduce the loss of dry ice in the dry ice sublimation heat transfer basket.

The air supply unit and the air return unit are respectively provided with an air return temperature controller for controlling the start and stop of the small-flow direct current, the air supply unit and the air return unit. The return air temperature controller is beneficial to the matching of cold load in the precooling operation process, avoids litchi frostbite and reduces the electric load of the direct current fan.

Wherein, the opening hole on the box body of the precooling cavity is provided with a small pressure difference exhaust valve. Because the air pressure in the box rises due to sublimation of the dry ice in the relatively closed box body, the air in the box can be automatically squeezed and discharged in time by the small-pressure-difference exhaust valve, and the air in the box can be timely squeezed and discharged, so that the air bath of high-concentration low-temperature carbon dioxide is obtained in the litchi precooling process while the small positive pressure in the box is ensured, and the litchi or vegetable and fruit is ensured to be subjected to the fresh-keeping treatment of reducing and sterilizing.

The dry ice slow-release refrigeration cavity is provided with a dry ice injection door for filling dry ice and facilitating installation, maintenance and repair of the slow-release cooling circulating fan and the slow-release filler. The pre-cooling cavity is provided with a heat preservation door for opening and placing the litchi or other vegetables and fruits picked in the field, and the independently arranged heat preservation door enables the litchi or vegetables and fruits to be convenient to load and unload. The two independently arranged doors can avoid unnecessary release and loss of cold energy of the dry ice before precooling and starting.

The dry ice slow-release pre-freezer box body is characterized in that the dry ice slow-release pre-freezer box body is composed of two layers, wherein the outer plate is a composite steel plate or a stainless steel plate, and the inner plate is a stainless steel thin plate; the cabinet body can wholly adopt polyurethane high pressure foaming to form, also can be assembled by the cabinet board and form, assembles the heat preservation cabinet body that the leakproofness is good through eccentric lock between the adjacent cabinet board. The box body adopting polyurethane high-pressure foaming can reduce the loss of cold energy in a dry ice storage stage and a sublimation precooling stage to the maximum extent, is convenient to be matched and installed with conveying tools in different forms, and has low manufacturing cost.

Wherein, the dry ice slow-release pre-refrigerator is fixedly arranged on the transport tool through the fixing feet of the pre-refrigerator.

Compared with the prior art, the invention has the beneficial effects that:

1. the method utilizes the characteristics of huge heat absorption latent heat and large temperature difference heat exchange of sublimation of the dry ice as a cold source on one hand, and utilizes the carbon dioxide gas sterilization function of sublimation of the dry ice on the other hand, so that the litchi fresh-keeping target which cannot be achieved by other precooling measures can be realized.

2. The air returning slow-release cavity and the buffer cavity in the invention realize matching of air returning circulation flow on one hand, and can weaken sublimation of dry ice when the fan is in a stop state on the other hand, so as to realize matching release between sublimation of the dry ice and precooling cold quantity requirements.

3. The invention only needs the configuration of the direct current fan with small capacity load, the electricity consumption of the direct current fan comes from the battery of the transport tool, and the additional burden of the charge capacity of the transport tool is little increased.

4. The invention is arranged on a transport vehicle which is favorable for driving on a small road in the countryside, so that the litchis picked from the field can be gathered in a short distance.

Drawings

Fig. 1 is a schematic sectional structure view of the bottom of the mobile dry ice slow-release precooling litchi fresh-keeping device.

Fig. 2 is a schematic diagram of a front view structure of the mobile dry ice slow-release precooling litchi fresh-keeping device.

Fig. 3 is a structural schematic diagram of the mobile dry ice slow-release precooling litchi fresh-keeping device in the right view.

Fig. 4 is a schematic diagram of a top view structure of the mobile dry ice slow-release precooling litchi fresh-keeping device.

Fig. 5 is a schematic structural diagram of the movable dry ice slow-release precooling litchi fresh-keeping device provided by the invention and assembled on a transport tool.

Fig. 6 is a schematic diagram of a sieve plate of a dry ice sublimation heat exchange basket of the mobile dry ice slow-release precooling litchi fresh-keeping device.

Fig. 7 is a perspective view of a dry ice sublimation heat exchange basket in embodiment 1 of the mobile dry ice slow-release precooling litchi fresh-keeping device of the invention.

Fig. 8 is a front view of a dry ice sublimation heat exchange basket in embodiment 1 of the mobile dry ice slow-release precooling litchi fresh-keeping device of the invention.

Fig. 9 is a front view of a dry ice sublimation heat exchange basket in embodiment 2 of the mobile dry ice slow-release precooling litchi fresh-keeping device of the invention.

Detailed Description

The invention is described in detail below with reference to the figures and the specific embodiments.