阅读说明：本技术 敌百虫连续化造粒工艺装备 (Continuous granulating process equipment for trichlorfon ) 是由 孟长春 吉伟 孙春楼 陆沈华 潘风春 张维高 于 2021-07-29 设计创作，主要内容包括：本发明提供了一种敌百虫连续化造粒工艺装备,将合成的敌百虫物料放至保温釜中逐渐降温,保证物料呈液体状态,再通过进料泵将物料输送至预结晶器中稍微降温。通过预结晶器流出的敌百虫浆料,送至造粒机中。通过布料器将物料滴落在环形钢带上,布料器与环形钢带之间可以具有冷却液喷淋装置,使得敌百虫液滴滴落在冷却液中形成坚硬的球状白色颗粒后流出,最后再烘干、冷却处理。本发明基本没有三废排放,降低了职业健康伤害；敌百虫合成产生的热量通过热交换回收利用,环保节能；成品的颗粒大小更加均匀圆润,提高了产品外观和生产效率。(The invention provides continuous granulating process equipment for trichlorfon, which is characterized in that a synthesized trichlorfon material is placed in a heat-insulating kettle to be gradually cooled, the material is ensured to be in a liquid state, and then the material is conveyed to a pre-crystallizer through a feed pump to be slightly cooled. And d, conveying the trichlorfon slurry flowing out of the pre-crystallizer to a granulator. The material is dripped on the annular steel belt through the distributor, and a cooling liquid spraying device can be arranged between the distributor and the annular steel belt, so that the trichlorfon liquid drips in the cooling liquid to form hard spherical white particles and then flows out, and finally, drying and cooling treatment are carried out. The invention basically has no three wastes discharge, reduces occupational health injury; the heat generated by the synthesis of the trichlorfon is recycled through heat exchange, so that the environment is protected and the energy is saved; the particle size of the finished product is more uniform and mellow, and the appearance and the production efficiency of the product are improved.)

1. A continuous granulating process for trichlorfon comprises gradually cooling the synthesized trichlorfon material in a reaction kettle or a heat-insulating kettle to ensure that the material is in a liquid state, and conveying the material to a pre-crystallizer; the method is characterized in that: the shell of the pre-crystallizer is provided with a heat exchange pipeline, so that the liquid trichlorfon material is cooled to 70-75 ℃ as soon as possible to be in a flowable slurry state;

and (3) controlling a certain flow rate to send the trichlorfon slurry into a granulator, dripping the material on an annular steel belt through a distributor, cooling to form hard white particles, shoveling down the hard white particles through a scraper, and directly entering into a package.

2. The continuous granulating process equipment of trichlorfon as claimed in claim 1, wherein: and a stirring scraper is arranged in the pre-crystallizer, so that the materials are prevented from accumulating adherent.

3. The continuous granulating process equipment of trichlorfon as claimed in claim 1, wherein: an aliphatic hydrocarbon cooling liquid spraying device is arranged between the distributing device and the annular steel belt, droplets of the trichlorfon drop in the cooling liquid and are solidified into white particles, the white particles are precipitated on the steel belt or are suspended in the cooling liquid, and the white particles travel with the steel belt or flow out together with the cooling liquid;

the flowing solid-liquid mixed material is heated to a temperature which is higher than the boiling point of the aliphatic hydrocarbon cooling liquid and lower than the melting point of the trichlorfon by a dryer, and the dried trichlorfon particles are subjected to proper temperature reduction treatment.

4. The continuous granulating process equipment of trichlorfon as claimed in claim 3, wherein: the cooling liquid is n-hexane or cyclohexane, and the drying temperature is controlled to be more than 80.7 and less than 83 ℃.

5. The continuous granulating process equipment of trichlorfon as claimed in claim 3 or 4, wherein: hot water generated in the heat exchange pipeline of the pre-crystallizer is used as a drying heat source.

Technical Field

The invention relates to an automatic production technology of granular pesticide.

Background

The trichlorfon is a phosphonate organophosphorus insecticide, mainly takes stomach toxicity and contact poisoning to insects, and has the characteristics of high efficiency, low toxicity, low residue, water solubility and the like. The pure dipterex is white crystal powder, has aromatic smell, and has a melting point of 83-84 ℃, and a solubility (g/L, 25 ℃): water 154, chloroform 750, diethyl ether 170 and benzene 152. But is substantially insoluble in aliphatic hydrocarbons and petroleum, n-pentane 1.0, n-hexane 0.8, and cyclohexane, which has a solubility of the order of μ g/ml, and is hardly soluble.

The existing production process mainly uses chloral and dimethyl phosphite as raw materials to prepare trichlorfon through a one-step method, the content of the synthesized trichlorfon is basically 90-93%, and the trichlorfon contains impurities such as demethylation trichlorfon and dechlorinated trichlorfon. At present, 90% of technical grade trichlorfon is obtained through a melt crystallization process, specifically, liquid trichlorfon in a molten state is manually filled into a high-temperature resistant plastic bag, the bag opening is tied and then is placed into a crystallization field, crystallization and solidification are carried out in a natural cooling mode, and solidified trichlorfon materials are crushed through a machine and then are made into small packages. The traditional trichlorfon crystallization process has the following problems: the production mode has large floor area, intermittent production and low production efficiency; secondly, the packaging material is seriously wasted; the trichlorfon is in the liquid bag and the blocky trichlorfon is crushed; after the trichlorfon is crystallized after liquid packaging, a small amount of generated trichlorfon solids are washed by water on the field to generate a large amount of phosphorus-containing wastewater.

The Chinese patent of the patent publication No. CN1185930C discloses a granulating and tabletting process of trichlorfon raw pesticide, which comprises the following steps: cooling water is introduced into a pre-crystallization kettle of high-temperature melt liquid to reduce the temperature of materials to 55-60 ℃, the cooled materials circulate outside the kettle through a circulating pump and an external circulating pipe, then the materials are beaten into a rotary steel belt condensation granulator, the materials are dripped on an annular steel belt which runs on two rollers through a distributor above the rotary steel belt condensation granulator to form hemispherical grains or flaky grains, atomized water sprayed from a water spraying groove with a water inlet pipe and a water outlet pipe in the middle of the annular steel belt is cooled and solidified, and the atomized water is shoveled by a scraper arranged at the other end to be directly packaged. Although the method can complete the granulation of the trichlorfon, in the actual production process, the continuous supply of the trichlorfon material for generating a certain amount of crystal seeds by a single crystallization kettle is difficult, and the continuous operation is difficult to realize. The crystallization quantity is too small, so that the materials can not meet the granulation requirement, the crystallization time on a steel belt of a granulator is longer, and the production efficiency is reduced; excessive crystallization quantity can cause the material to be thicker, the condensation speed of the material is accelerated when the material enters a distributor above a rotary steel belt condensation granulator, and the possibility of blockage of the distributor is high.

(the utility model discloses a chinese utility model patent of grant publication No. CN 106632473B discloses a continuous crystallization device of crude trichlorfon and a method thereof, the device includes a steel belt, a transfer roller and a cooling device, a distributor is arranged above the steel belt feeding end, the distributor is communicated with the feeding pipe, a heat tracing device is arranged at the periphery of the feeding pipe, a cooling device is arranged below the middle part of the steel belt, a discharging device is arranged at the discharging end of the steel belt, and the discharging end of the steel belt is connected with a crusher.

N-hexane had a boiling point of 69 ℃ (342K) and cyclohexane had a boiling point of 80.7.

Disclosure of Invention

The purpose of the invention is as follows:

aiming at the problems in the traditional trichlorfon crystallization process, the continuous trichlorfon granulation process equipment which is high in production efficiency, free of scaling, round and smooth in particles, energy-saving and environment-friendly is provided.

The technical scheme is as follows:

according to the continuous granulating process equipment for the trichlorfon, the synthesized trichlorfon material is placed into the reaction kettle (or the heat preservation kettle) to be gradually cooled, the material is ensured to be in a liquid state, and then the material is conveyed into the pre-crystallizer through the feeding pump. The shell of the pre-crystallizer is provided with a heat exchange pipeline (condensed water enters the shell and is heated to form hot water and flows out), so that the liquid trichlorfon material is cooled to 70-75 ℃ as soon as possible, partial crystal seeds are conveniently separated out, and the crystal seeds cannot be completely separated out at the same time to form a flowable slurry state.

In addition, a stirring scraper is arranged in the pre-crystallizer, so that the materials are prevented from being adhered to the wall and accumulating. And after the materials meet the granulation requirements, opening a discharge pump, and allowing the trichlorfon slurry to flow out through a pre-crystallizer.

And controlling a certain flow rate to send the trichlorfon slurry into the granulator. The material is dropped on the annular steel belt through the distributing device, hard hemispherical white particles are formed after cooling, and then the hard hemispherical white particles directly enter the package after being shoveled by the scraper.

It is preferable to have a cooling liquid spray device between the distributor and the endless steel belt so that the droplets of trichlorfon are dropped into a cooling liquid (preferably a liquid that does not substantially dissolve trichlorfon, such as liquid aliphatic hydrocarbons; further preferably hexane, cyclohexane having a boiling point lower than the melting point of trichlorfon) to solidify into white particles. The heat exchange effect is good, the cooling is fast, spherical particles can be formed in liquid without being influenced by self gravity and the elasticity of the steel strip, the forming is attractive, the particles are precipitated on the steel strip or suspended in the cooling liquid and flow out along with the walking of the steel strip or the flowing of the cooling liquid.

The flowing solid-liquid mixed material is heated by a dryer (hot water generated in a heat exchange pipeline of the pre-crystallizer can be used as a drying heat source, the heat source is used in a heat energy system, energy is saved, consumption is reduced, the steel strip can be directly dried, and a heat exchange device is arranged below the steel strip) to reach the temperature which is higher than the boiling point of hexane or cyclohexane and lower than the melting point of trichlorfon, so that the hexane or cyclohexane is gasified, discharged and collected, cooled (the steel strip can be air-cooled or a cooling water loop is arranged below the subsequent steel strip for cooling) and then recycled; and (3) carrying out proper cooling treatment on the dried trichlorfon particles, and finally packaging and transporting.

Extruding and granulating the trichlorfon, namely evaporating and recovering hexane at the temperature of more than 69 ℃ and below 83 ℃ by taking hexane as cooling liquid. If the trichlorfon is cooled by adopting a cyclohexane solution, the trichlorfon is almost insoluble and does not run off, the effect is better, the drying temperature is controlled to be more than 80.7 and less than 83 ℃ by manual or automatic induction (a sensor can be configured to sense the temperature, and a PLC controller can be configured to control the drying temperature), and the cyclohexane is recycled.

And finally, collecting and packaging the solid trichlorfon pure material.

Has the advantages that:

the invention adopts liquid recovery, can reduce dust, and can recycle hexane or cyclohexane without discharge, thereby reducing environmental pollution and reducing occupational health injury; the heat generated by the synthesis of the trichlorfon can meet the process requirements of gradual temperature reduction and then heating, and can be recycled, so that the energy is saved and the consumption is reduced. The invention saves the cost of packing materials and labor cost, realizes continuous granulation, and ensures that the particle size of the materials is more uniform and mellow because the insoluble solution is used for receiving the trichlorfon particles, thereby improving the production efficiency and the phase of selling the products.

Description of the drawings:

FIG. 1 is a schematic view of a device connection configuration of the present invention;

in the figure, 1-trichlorfon reaction kettle; 2-a pre-crystallizer; 3-slurry pump; 4-granulating machine; 5-a spraying device; 6-stainless steel band; 7-recycling device; 8-a drying device; 9-a cooling device; 10-trichlorfon granules.

Detailed Description

The first embodiment is as follows:

as shown in fig. 1, 7.2t of trichlorfon material is put into a heat preservation kettle, hot water is used for preserving heat of the material, the internal temperature of the trichlorfon material is controlled to be 70 ℃, a material valve at the bottom is opened, a feeding pump is started, and the flow of the discharging pump is controlled to be 3m³And h, conveying the trichlorfon liquid material into a pre-crystallizer, wherein a hinge scraper plate is arranged in the pre-crystallizer in a stirring manner, so that the material is prevented from being accumulated on the wall, the flowability of the material is ensured, an external circulating pump of the pre-crystallizer is started at the same time, and the flow is controlled to be 10 m³H, strengthening heat exchange through forced circulation to ensure that the material forms slurry with crystals in a short time, and cooling the slurry by a pre-crystallizer to form partial junctionsThe brilliant trichlorfon material passes through the loop pipeline and returns to the heat preservation kettle again, and on the loop pipeline, the viscosity meter is installed, when the viscosity reaches 2000 centipoises, the inlet valve of the discharge pump is opened, the discharge pump is started, and the flow of the material is controlled to be 1m³The method comprises the following steps of conveying a trichlorfon material to a distributor of a granulator, further and uniformly spraying a trichlorfon slurry onto a steel belt through a nozzle on the distributor, wherein the steel belt is provided with a cooling water cooling system, the trichlorfon material is further cooled on a rigid belt and is solidified and molded, hard-block hemispherical trichlorfon particles can be formed within 30-40 s, the hard-block trichlorfon particles are shoveled down by a scraper when the steel belt runs and reaches the running end point of the steel belt, the hard-block trichlorfon particles enter an automatic packaging system, and in order to meet continuous granulation of the trichlorfon material, a fused liquid material coming out of a synthesis kettle needs to be controlled by 1m³The speed of the/h is continuously added into the heat preservation kettle, the materials are fully mixed with the materials returned to the heat preservation kettle again after being cooled from the pre-crystallizer, the viscosity of the materials is reduced, so that no solid materials are separated out from the heat preservation kettle, the continuous production of the whole process is realized, the daily treatment capacity can reach 41.52t, and the requirement of the existing trichlorfon capacity is met.

Example two:

putting 7.2t of trichlorfon material into the heat-preservation kettle, preserving heat of the material by using hot water, controlling the internal temperature of the trichlorfon material to be 75 ℃, opening a material valve at the bottom, starting a feeding pump, and controlling the flow of the feeding pump to be 2m³And h, conveying the trichlorfon liquid material into a pre-crystallizer, wherein a hinge scraper plate is arranged in the pre-crystallizer in a stirring manner, so that the material is prevented from being accumulated on the wall, the flowability of the material is ensured, an external circulating pump of the pre-crystallizer is started at the same time, and the flow is controlled to be 5m³The method comprises the steps of/h, strengthening heat exchange through forced circulation to ensure that the materials form slurry with crystals in a short time, cooling the partially crystallized dipterex materials formed by the pre-crystallizer through a loop pipeline, returning the partially crystallized dipterex materials to a heat preservation kettle again, installing a viscosity meter on the loop pipeline, opening an inlet valve of a discharge pump when the viscosity reaches 2000 centipoises, starting the discharge pump, and controlling the flow of the materials to be 0.5m³H, conveying the trichlorfon material to a distributor of a granulator, and passing the trichlorfon material through the distributorThe trichlorfon slurry is further uniformly sprayed into a cyclohexane solution to be cooled and condensed into spherical particles, and a conveying steel belt is arranged below the liquid level of the cyclohexane.

As shown in fig. 1, the effluent solid-liquid mixture is directly dried on a steel belt (a heat exchange device is arranged below the steel belt) to a temperature higher than the boiling point of hexane or cyclohexane and lower than the melting point of dipterex, so that hexane or cyclohexane is gasified, discharged and collected, finally cooled (a cooling water loop is arranged below the subsequent steel belt for cooling), packaged and transported.