A processing system for rice paper black liquor

Abstract

The invention belongs to the technical field of rice paper wastewater treatment, and specifically relates to a treatment system for rice paper black liquor, including a main tower, a secondary tower, a receiving tower and a recovery tower, an atomizing spray gun is arranged on the top of the main tower, a black liquor inlet pipe is connected to the atomizing spray gun, the main tower, the secondary tower and the recovery tower are connected in series with an exhaust pipe in sequence, a spray device and a water vapor exhaust pipe are arranged on the upper part of the recovery tower, a particle discharge port is arranged at the bottom of the main tower and the secondary tower, and the particle feed pipe of the receiving tower is communicated with the particle feed pipe of the receiving tower, and a particle collecting device is arranged at the bottom of the receiving tower. The treatment system for rice paper black liquor of the invention has low investment, simple principle, convenient operation and high treatment efficiency, and components such as lignin that can be recycled in the black liquor are all collected in solid form, and water after solid-liquid separation can also be collected and reused, and the treatment of rice paper black liquor can be completed without the need to add other reagents, thereby greatly reducing environmental pollution.

Description

Technical Field

[0001] The invention belongs to the technical field of rice paper wastewater treatment, and in particular relates to a rice paper black liquor treatment system. Background Art

[0002] Xuan paper black liquor is the pulp washing liquid after washing and boiling in the process of producing Xuan paper. It contains refractory lignin and its degradation derivatives. Lignin is a three-dimensional network polymer with an aromatic structure and has comprehensive utilization value. Papermaking black liquor is also a highly alkaline industrial wastewater, which has serious pollution and destructive effects on water bodies and the ecological environment. Therefore, how to reasonably and effectively treat and utilize Xuan paper black liquor is the most critical issue in solving the discharge of pollutants from Xuan paper wastewater.

[0003] At present, the main methods used for treating Xuan paper black liquor include alkali recovery method, acid precipitation method, flocculation sedimentation method, chemical oxidation method, biological treatment method, etc. These methods often have high investment, complex process, high energy consumption, and low comprehensive utilization efficiency, and cannot completely solve the problem of Xuan paper black liquor. Summary of the invention

[0004] The purpose of the present invention is to provide a system for treating rice paper black liquor, which can realize rapid and efficient treatment of rice paper black liquor.

[0005] The treatment system has low investment, simple treatment process, high treatment efficiency of rice paper black liquor and high recovery rate of recyclable materials.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a treatment system for rice paper black liquor, comprising a main tower, a secondary tower, a collecting tower and a recovery tower, an atomizing spray gun is arranged on the top of the main tower, the atomizing spray gun is connected to a black liquor inlet pipe, the main tower, the secondary tower and the recovery tower are connected in series with an exhaust pipeline in sequence, a spray device and a water vapor exhaust pipe are arranged on the upper part of the recovery tower, particle discharge ports are arranged at the bottom of the main tower and the secondary tower and are connected to the particle feed pipe of the collecting tower, and a particle collecting device is arranged at the bottom of the collecting tower.

[0007] The treatment system of the Xuan paper black liquor of the present invention has low investment, simple principle, convenient operation and high treatment efficiency. Recyclable components such as lignin in the black liquor are all collected in solid form, and water after solid-liquid separation can also be collected and reused. The treatment of the Xuan paper black liquor can be completed without adding other reagents, which greatly reduces environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram of the treatment system of Xuan paper black liquor of the present invention.

[0009] In the figure: 10-main tower, 11-atomizing spray gun, 20-secondary tower, 30-collecting tower, 31-particle feeding pipe, 32-particle collecting device, 40-recovery tower, 41-spraying device, 42-steam exhaust pipe, 43-liquid discharge pipe, 50-particle deceleration fence, 61-recovery fan, 62-main fan; Indicates the direction of hot air, cold air or water vapor in the pipeline. Indicates the direction of liquid or granular material in the pipeline. DETAILED DESCRIPTION

[0010] The rice paper black liquor processing system of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0011] A system for treating black liquor of rice paper comprises a main tower 10, a secondary tower 20, a collecting tower 30 and a recovery tower 40. An atomizing spray gun 11 is arranged on the top of the main tower 10, and a black liquor inlet pipe is connected to the atomizing spray gun 11. The main tower 10, the secondary tower 20 and the recovery tower 40 are connected in series in sequence through an exhaust pipeline. A spray device 41 and a water vapor exhaust pipe 42 are arranged on the upper part of the recovery tower 40. Particle discharge ports are arranged at the bottom of the main tower 10 and the secondary tower 20 and are connected to the particle feed pipe 31 of the collecting tower 30. A particle collecting device 32 is arranged at the bottom of the collecting tower 30.

[0012] After the rice paper black liquor enters the atomizing spray gun, it enters the main tower in the form of tiny droplets. After hot air is introduced into the main tower, most of the water in the tiny droplets evaporates and separates into granular materials and water vapor. The speed of the granular materials decreases until they fall, and finally they are collected in the collecting tower; the hot air, water vapor and the remaining tiny droplets enter the secondary tower to repeat the process in the main tower. The granular materials falling from the main tower and the secondary tower enter the collecting tower, and the airflow with residual black liquor droplets in the secondary tower enters the recovery tower. After being sprayed by the spray device, black liquor is formed and gathered at the bottom of the recovery tower.

[0013] As a preferred solution, the connection point between the main tower 10 and the hot air source is lower than the spray port of the atomizing spray gun 11. This arrangement allows the hot air to quickly contact the atomized black liquor entering the main tower, and after a physical heat exchange process, the water in the black liquor evaporates, the solid matter falls, and the solid and liquid phases in the black liquor are separated, which speeds up the treatment process of the black liquor.

[0014] Preferably, the main tower 10 and the secondary tower 20 are provided with a particle deceleration fence 50. The liquid in the tiny black droplets dried by hot air evaporates and quickly turns into granular material, i.e., pellets. The pellets rotate and flow in the main tower or the secondary tower with the airflow. In order to accelerate the pellet collection process, a particle deceleration fence 50 is provided in the main tower and the secondary tower, such as a fence with a large gap, or a spiral rod consistent with the flow direction of the airflow, which can not only allow the airflow to pass smoothly, but also generate friction and collision with the contacted pellets, so that the pellets fall to the bottom of the tower under the action of gravity.

[0015] Preferably, the feed pipe 31 of the receiving tower 30 is connected to a dehumidified cold air source, and the receiving tower 30 is also provided with a recovery pipeline connected to the main tower 10, and the recovery pipeline is provided with a recovery fan 61. The pellets gathered at the bottom of the main tower and the secondary tower enter the receiving tower under the action of the dehumidified cold air flow, and most of the pellets fall down and are collected. A certain amount of residual pellets still exist in the air flow, and enter the main tower through the recovery pipeline for circulation treatment, which can further increase the recovery rate of recyclable substances in the black liquor.

[0016] Preferably, a main fan 62 is provided on the connecting pipeline between the secondary tower 20 and the recovery tower 40, the air outlet of the main fan 62 extends to the interior of the recovery tower 40 and the air outlet position is lower than the spray device 41, and a drain pipe 43 is provided at the bottom of the recovery tower 40, and the drain pipe 43 is connected to the water inlet of the spray device 41 or the black liquor inlet of the main tower 10. There are still small droplets or particles that are not recovered in the airflow in the secondary tower. After the airflow enters the recovery tower, it is dissolved in water again under the action of the spray device to become black liquor and accumulate at the bottom of the tower. The black liquor at the bottom of the tower with low concentration can be pumped to the spray device. As the treatment system continues to operate, the concentration of the black liquor at the bottom of the recovery tower continues to increase. At this time, the pumping direction can be changed to pump the black liquor at the bottom of the tower to the black liquor inlet of the main tower 10 for circulating treatment of the black liquor.

[0017] By adopting the above scheme, during the treatment of Xuan paper black liquor, both the airflow of residual black liquor droplets and the airflow of residual granules can be returned to the system for recycling treatment, and the recyclable components in the black liquor are fully recovered in the form of granules, thereby achieving efficient treatment and high recovery rate of Xuan paper black liquor. In addition, the process is simple and the investment cost is low, which is suitable for Xuan paper manufacturing enterprises to vigorously promote.

Claims

1. A system for treating rice paper black liquor, characterized in that: The invention comprises a main tower (10), a secondary tower (20), a receiving tower (30) and a recovery tower (40); an atomizing spray gun (11) is arranged on the top of the main tower (10); a black liquor inlet pipe is connected to the atomizing spray gun (11); the main tower (10), the secondary tower (20) and the recovery tower (40) are connected in series in sequence through an exhaust pipe; a spray device (41) and a water vapor exhaust pipe (42) are arranged on the top of the recovery tower (40); particle discharge ports are arranged at the bottom of the main tower (10) and the secondary tower (20) and are connected to the particle feed pipe (31) of the receiving tower (30); a particle collecting device (32) is arranged at the bottom of the receiving tower (30); and particle deceleration barriers (50) are arranged inside the main tower (10) and the secondary tower (20); A main fan (62) is provided on the connecting pipeline between the secondary tower (20) and the recovery tower (40); an air outlet of the main fan (62) extends into the interior of the recovery tower (40) and is located below the spray device (41); a liquid discharge pipe (43) is provided at the bottom of the recovery tower (40); and the liquid discharge pipe (43) is connected to a water inlet of the spray device (41) or a black liquor inlet of the main tower (10).

2. The system for treating rice paper black liquor according to claim 1, characterized in that: The connection point between the main tower (10) and the hot air source is lower than the spray port of the atomizing spray gun (11).

3. The system for treating rice paper black liquor according to claim 1, characterized in that: The particle feed pipe (31) of the receiving tower (30) is connected to a dehumidified cold air source. The receiving tower (30) is also provided with a hot air recovery pipeline connected to the main tower (10). A recovery fan (61) is provided on the hot air recovery pipeline.

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