System and method for preparing sulphoaluminate cement from solar energy stored heat dried sludge

Patent metadata

Field	Value
Publication number	US-12583790-B2
Application number	US-202117915623-A
Country	US
Kind code	B2
Filing date	Sep 9, 2021
Priority date	Sep 7, 2021
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

A system and method for preparing sulphoaluminate cement from solar energy stored heat dried sludge. Solar concentrator connected to high-temperature molten salt storage tank, superheater, preheating-evaporator and low-temperature molten salt storage tank to form mixed molten salt heat transfer-heat storage circulation system; superheated steam in superheater enters ultra-disc dryer, and ultra-disc dryer connected to water storage tank and preheating-evaporator superheater to form water heat transfer circulation system; wet sludge bin connected to ultra-disc dryer and inlet of dried sludge bin, and dried sludge conveyed to dried sludge bin for storage; and cement production system separately connected with waste gas outlet of ultra-disc dryer and outlet of dried sludge bin. System can use valley electricity to supplement heat at any specific time, and coupled with cement kiln; waste gas introduced into cement kiln for waste burning; dried sludge mixed with other solid waste to enter cement kiln to prepare sulphoaluminate cement.

First claim

What is claimed is:

1 . A system for preparing sulphoaluminate cement from solar energy stored heat dried sludge, wherein a solar concentrator is successively connected to a high-temperature molten salt storage tank, a superheater, a preheating-evaporator and a low-temperature molten salt storage tank to form a mixed molten salt heat transfer-heat storage circulation system; superheated steam in the superheater enters an ultra-disc dryer, and the ultra-disc dryer is successively connected to a water storage tank and a preheating-evaporator superheater to form a water heat transfer circulation system; a wet sludge bin is connected to the ultra-disc dryer and an inlet of a dried sludge bin, and dried sludge is conveyed to the dried sludge bin for storage; and a cement production system is separately connected with a waste gas outlet of the ultra-disc dryer and an outlet of the dried sludge bin.

2 . The system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , wherein the solar concentrator is a parabolic trough type solar concentrator; or, a molten salt pump is further disposed on a connection pipeline of the mixed molten salt heat transfer-heat storage circulation system; and further, the molten salt pump is disposed on a connection pipeline of the solar concentrator and the low-temperature molten salt storage tank.

3 . The system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , wherein an electric cabinet and a molten salt heater are further disposed in the mixed molten salt heat transfer-heat storage circulation system, a mixed molten salt is heated through the electric cabinet and the molten salt heater; or, the mixed molten salt comprises potassium nitrate, sodium nitrate and graphite.

4 . The system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , wherein a circulating water pump is further disposed in the water heat transfer circulation system; further, the circulating water pump is disposed on a connection pipeline of the water storage tank and the preheating-evaporator; or a warning water level automatic water supplement device is disposed in the water storage tank.

5 . The system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , wherein screw conveying equipment is disposed on a connection pipeline of the wet sludge bin and the ultra-disc dryer; or, a condenser is disposed on a connection pipeline of the cement production system and a waste gas outlet of the ultra-disc dryer.

6 . A method for preparing sulphoaluminate cement from solar energy stored heat dried sludge, based on the system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , comprising:
heating a mixed molten salt by the solar concentrator, a part of the heated high-temperature mixed molten salt flowing to the high-temperature molten salt storage tank for storage, and the other part of the heated high-temperature mixed molten salt flowing to the superheater and the preheating-evaporator for heat exchange; making the mixed molten salt after heat exchange flow to the low-temperature molten salt storage tank, and re-flow into the solar concentrator under the action of the molten salt pump; making superheated steam formed after performing heat exchange in the superheater enter the ultra-disc dryer to be subjected to heat exchange with wet sludge, the superheated steam condensing in the heat exchange process and entering the water storage tank, and water in the water storage tank re-entering the preheating-evaporator and the superheater for circulation under the action of the circulating water pump; conveying dried sludge to the dried sludge bin for storage, and the dried sludge entering the cement production system for preparing the sulphoaluminate cement after being mixed with solid waste; and making waste gas formed in the sludge drying process enter a decomposing furnace of the cement production system for incineration.

7 . The method for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 6 , wherein a temperature of the heated high-temperature mixed molten salt is 400-500° C.; or, a temperature of the mixed molten salt after heat exchange is 100-200° C.; or, a temperature of the superheated steam is 180-250° C.

8 . The method for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 6 , wherein the wet sludge is flocculated and compressed sludge; further, the flocculation is performed with iron salt and mechanical compression is performed; or, a dry specific gravity of dried sludge to solid waste during mixing is 5-30:15-40; further, the solid waste is one or a combination of more of waste incineration fly ash, desulphurized gypsum, aluminium ash or calcium carbide slag; yet further, a dry specific gravity of the dried sludge to the waste incineration fly ash, the desulfurized gypsum, the aluminum ash or the calcium carbide slag is 13-24:5-30:18-35:17-27:12-20.

9 . The method for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 6 , wherein when the sun illumination intensity is low, the mixed molten salt is heated by using the valley electricity at night through the electric cabinet and the molten salt heater, by this time, valves at both ends of the solar concentrator are in a closed state, and the molten salt heater replaces the solar concentrator to supplement stored heat of the high-temperature molten salt.

10 . An application of the system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 and/or the method for preparing sulphoaluminate cement from solar energy stored heat dried sludge based on the system for preparing sulphoaluminate cement from solar energy stored heat dried sludge according to claim 1 , comprising:
heating the mixed molten salt by the solar concentrator, the part of the heated high-temperature mixed molten salt flowing to the high-temperature molten salt storage tank for storage, and the other part of the heated high-temperature mixed molten salt flowing to the superheater and the preheating-evaporator for heat exchange; making the mixed molten salt after heat exchange flow to the low-temperature molten salt storage tank, and re-flow into the solar concentrator under the action of the molten salt pump;
making superheated steam formed after performing heat exchange in the superheater enter the ultra-disc dryer to be subjected to heat exchange with wet sludge, the superheated steam condensing in the heat exchange process and entering the water storage tank, and water in the water storage tank re-entering the preheating-evaporator and the superheater for circulation under the action of the circulating water pump; conveying dried sludge to the dried sludge bin for storage, and the dried sludge entering the cement production system for preparing the sulphoaluminate cement after being mixed with solid waste; and making waste gas formed in the sludge drying process enter the decomposing furnace of the cement production system for incineration.

Assignees

• Univ Shandong

Inventors

• Wang Wenlong
• Zhang Jiazheng
• Mao Yanpeng
• Huang Yanmin

Classifications

• C04B28/14

  containing calcium sulfate cements {(gypsum-paper plates E04C)} · CPC title

• F24S23/71

  with parabolic reflective surfaces (with cylindro-parabolic reflective surfaces F24S23/74) · CPC title

• F24S10/70

  the working fluids being conveyed through tubular absorbing conduits · CPC title

• C04B2290/20

  Integrated combined plants or devices, e.g. combined foundry and concrete plant · CPC title

• C04B7/46

  electric · CPC title