CN206751663U - Lime slaking prepares the residual heat using device of calcium hydroxide refining - Google Patents

Abstract

The utility model discloses the residual heat using device that a kind of lime slaking prepares calcium hydroxide refining, including digestion machine, raw slurry aging tank, the lime bin on digestion machine, in addition to hot water cistern, buffer pool, pump for mortar transmission, heat exchanger, cyclone hydraulic separators, vibratory sieve, refining storage tank, normal temperature pond, high-pressure water-flushing device, back water pump.Reaction heat caused by lime slaking can be recycled using the device, effectively Resource Recycling Utilization, reduces energy consumption and production costs, and the impurity in calcium hydroxide refining can also be effectively removed, suitable for the production of nano-calcium carbonate.

Description

Waste heat utilization device for preparing calcium hydroxide fine pulp from lime digestion

technical field

The utility model relates to the technical field of nano-calcium carbonate production, in particular to a waste heat utilization device for preparing calcium hydroxide fine pulp by digesting lime.

Background technique

Nano-calcium carbonate is currently used domestically to obtain lime by calcination of limestone, digested with water, refined and sieved, and then carbonized with kiln gas to obtain nano-calcium carbonate. In the process of preparing nano-calcium carbonate by carbonization, the temperature of the water used for the digestion of lime has a great influence on the subsequent production. Using high-temperature digestion of limestone, the yield of milk of lime is high, and the milk of lime is relatively fine and dispersible. Under the same conditions of the carbonization process, the calcium carbonate product prepared by carbonization of milk of lime obtained by high-temperature digestion has a higher specific surface area, a smaller particle size after secondary agglomeration, and a lower oil absorption value. Generally, the temperature of water for lime digestion is best at 45-65°C. The higher the temperature of lime digestion, the faster the lime can be expanded, and the lime milk with fine particle size and good dispersibility can be obtained, and the yield of lime milk can be increased. The particles of lime milk are relatively fine, and industrial production allows the digestion reaction to be carried out at less than 100°C. At present, the hot water used for lime digestion to prepare calcium hydroxide concentrate is mainly obtained by heating cold water with boilers or steam. The disadvantages are: the investment and energy consumption of boilers and steam heating equipment are large, and the production cost is high. At the same time, lime contains many impurities, one is raw burnt limestone with larger particle size, undigested burnt lime and cinder, etc., and the other is SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ with high density, etc. If these impurities are not removed, it will affect the yield quality.

Utility model content

The technical problem solved by the utility model is to provide a kind of waste heat utilization device for lime digestion to prepare calcium hydroxide fine pulp, which can recycle the reaction heat generated by lime digestion and effectively recycle resources. It reduces energy consumption and production cost, and can effectively remove impurities in calcium hydroxide fine pulp, and is suitable for the production of nanometer calcium carbonate.

The technical scheme adopted by the utility model is: a waste heat utilization device for preparing calcium hydroxide fine pulp by digesting lime, including a digester, a raw pulp aging tank, a lime hopper installed on the digester, and a hot water storage tank, a buffer Pool, slurry pump, heat exchanger, hydrocyclone, vibrating screen, fine pulp storage tank, normal temperature pool, high-pressure flushing device, return pump; the hot water reservoir is connected to the feed end of the digester, The discharge end of the machine is connected with the buffer tank, and the buffer tank is also connected with the raw pulp aging tank, and the raw pulp aging tank is connected with the heat exchanger through the slurry pump and the slurry inlet pipe, and the slurry outlet of the heat exchanger The hydrocyclone is connected with the hydrocyclone through the pipeline, the hydrocyclone is connected with the vibrating screen through the pipeline, and the outlet of the vibrating screen is connected with the fine pulp storage tank through the pipeline; The pipes are connected; the normal temperature water pool is connected with the water inlet of the heat exchanger through the pipe, and the water outlet of the heat exchanger is connected with the hot water storage tank through the return pump and the pipe.

The heat exchanger is a plate heat exchanger.

The vibrating sieve is a secondary rotary vibrating sieve, the mesh number of the first stage is 150-250 mesh, and the mesh number of the second stage is 300-350 mesh.

The beneficial effects of the utility model are: 1. The utility model is provided with mechanisms such as a hot water storage tank, a buffer tank, a heat exchanger, a hydrocyclone, a vibrating screen, and a normal temperature pool, and the slurry obtained by lime digestion passes through the buffer tank. Then enter the raw pulp aging tank, and then use the slurry pump to transfer the aged pulp at about 50-70°C into the heat exchanger to exchange heat with normal temperature water and then reduce it to 18-28°C, and pass through the vibrating sieve. Afterwards, it can be directly used for carbonization to generate nano-calcium carbonate, which does not need to be cooled by a chiller, which saves electric energy; at the same time, the normal-temperature water in the normal-temperature pool is exchanged with the hot slurry with a higher temperature in the heat exchanger to obtain 45 The hot water at ~65°C flows into the hot water storage tank and can be used to digest lime, which can save the heating of the water in the hot water storage tank and reduce energy consumption and production costs; 2. Heat exchange in the utility model The slurry inlet pipe of the machine is connected with a high-pressure flushing device. After each heat exchange of the heat exchanger, the high-pressure flushing device can be used to flush the heat exchanger and the connecting pipes so that it is not easy to scale and prolong the service life of the heat exchanger and the connecting pipes 3. The utility model is provided with a secondary rotary vibrating screen, the mesh number of the first stage screen is 150-250 mesh, and the mesh number of the second stage screen is 300-350 mesh, which can effectively remove calcium hydroxide slurry. Impurities are removed to obtain calcium hydroxide fine pulp with qualified fineness.

Description of drawings

Fig. 1 is a schematic structural diagram of a waste heat utilization device for preparing calcium hydroxide fine slurry by digesting lime.

Explanation of symbols: 1-lime hopper; 2-hot water storage tank; 3-digester; 4-buffer tank; 5-raw pulp aging tank; 6-heat exchanger; 7-hydrocyclone; 8-vibration Sieve; 9-fine pulp storage tank, 10-normal temperature pool; 11-high-pressure flushing device; 12-stirring device; 13-slurry inlet pipe; 14-slurry delivery pump;

detailed description

Below in conjunction with accompanying drawing and concrete implementation the utility model is described further.

The waste heat utilization device for lime digestion to prepare calcium hydroxide fine pulp, as shown in Figure 1, includes a digester 3, a raw pulp aging tank 5, a lime hopper 1 installed on the digester 3, a hot water storage tank 2, a buffer Pool 4, pulp delivery pump 14, heat exchanger 6, hydrocyclone 7, vibrating screen 8, fine pulp storage tank 9, normal temperature pool 10, high pressure flushing device 11, return water pump 15 and other mechanisms. The hot water reservoir 2 is connected to the feed end of the digester 3, the discharge end of the digester 3 is connected to the buffer pool 4, the buffer pool 4 is also connected to the raw pulp aging tank 5, and the raw pulp aging tank 5 Connect the heat exchanger 6 through the slurry pump 14 and the slurry inlet pipe 13, the slurry outlet of the heat exchanger 6 is connected with the hydrocyclone 7 through the pipeline, and the hydrocyclone 7 is connected with the vibrating screen 8 through the pipeline , the discharge port of the vibrating screen 8 is connected with the fine pulp storage tank 9 through a pipeline; the high-pressure flushing device 11 is connected with the slurry inlet pipe 13 of the heat exchanger 6; the normal temperature pool 10 is connected with the heat exchanger through a pipeline The water inlet of 6 is connected, and the water outlet of heat exchanger 6 is connected with hot water storage tank 2 through backwater pump 15, pipeline. The heat exchanger 6 is a plate heat exchanger. The vibrating sieve 8 is a two-stage rotary vibrating sieve, the mesh number of the first stage is 150-250 mesh, and the mesh number of the second stage is 300-350 mesh. The seminal pulp storage tank 9 is provided with a stirring device 12 .

The working principle of the utility model is as follows: the slurry digested by the lime in the digester 3 enters the raw slurry aging tank 5 after passing through the buffer tank 4, and then the raw slurry of about 50-70 °C after aging is processed by the slurry pump 14. Enter the heat exchanger 6 to exchange heat with normal temperature water, the raw slurry can be reduced to 18-28 °C, and then sieved by the vibrating screen 8, it can be directly used for carbonization to generate nano-calcium carbonate; at the same time, the normal temperature water in the normal temperature pool 10 passes through In the heat exchanger 6, heat exchange is carried out with the hot slurry with a higher temperature to obtain hot water at 45-65°C, which is then transported to the hot water storage tank 2 by the return water pump 15 and can be used to digest lime, which can save the need for The heating of water in the hot water reservoir 2 reduces energy consumption and production costs.

The above-mentioned embodiments are only specific implementations of the present utility model, but the design concept of the present utility model is not limited thereto, and any insubstantial changes made to the utility model by using this concept should belong to the protection scope of the present utility model.

Claims (3)

1. The waste heat utilization device for lime digestion and preparation of calcium hydroxide fine pulp is characterized in that it includes a digester, a raw pulp aging tank, a lime hopper arranged on the digester, and also includes a hot water storage tank, a buffer tank, and a pulp delivery tank. Pumps, heat exchangers, hydrocyclones, vibrating screens, fine pulp storage tanks, normal temperature pools, high-pressure flushing devices, return pumps; hot water storage tanks are connected to the feed end of the digester, and the discharge of the digester The end is connected with the buffer pool, and the buffer pool is also connected with the raw pulp aging tank. The raw pulp aging tank is connected with the heat exchanger through the slurry pump and the slurry inlet pipe. The liquid separator is connected, the hydrocyclone is connected with the vibrating screen through a pipeline, and the outlet of the vibrating screen is connected with the fine pulp storage tank through a pipeline; the high-pressure flushing device is connected with the pulp inlet pipe of the heat exchanger; The normal temperature pool is connected to the water inlet of the heat exchanger through a pipeline, and the water outlet of the heat exchanger is connected to a hot water storage tank through a return pump and a pipeline. 2. The waste heat utilization device for preparing calcium hydroxide fine slurry by digesting lime according to claim 1, characterized in that: the heat exchanger is a plate heat exchanger. 3. The waste heat utilization device for preparing calcium hydroxide fine pulp by lime digestion according to claim 1, characterized in that: the vibrating sieve is a secondary rotary vibrating sieve, the mesh number of the first stage is 150-250 mesh, The mesh number of the second stage screen is 300-350 mesh.