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No toxic gases released to atmosphere and create alternative fuel which reduces dependence on petroleum and gas.

The main equipment of this unit is circulating fluidized-bed boiler of medium temperature & medium pressure (3.82 MPa, 450 ℃) and steam-condensing-type turbo-generator set.

The fuel of the circulating fluidized-bed boiler is the pyrolytic carbon from rotary bed, pyrolysis oil from oil and gas separator, and the remaining purified pyrolysis gas except that used by rotary bed. The air supply system comprises a primary air system and a secondary air system. The source of the air is the stench of the waste pretreatment unit. The primary air system mainly provides fluidized media for circulating fluidized-bed boiler, so that the fuel can be in a fluidized state in the boiler chamber and serve as the conveying medium of fuel feed system. The secondary air system mainly provides combustion air for circulating fluidized bed.

High temperature flue gas from combustion system flows through the high efficiency cyclone separator. Large fly ash particles in the flue gas are separated and return to the hearth while flue gas flows through the heating surface at boiler tail and goes through desulphurization and dust removal system. Then, the purified flue gas is sent to the chimney by induced draft fan and then discharged into the atmosphere. The NOx emission requirements of the flue gas can be achieved by using the SNCR system.

The superheated steam enters the main steam pipe after coming out of the outlet of the steam header of waste heat boiler, which is connected to the main throttle valve of turbine through shut-off valve. Then, the steam enters the turbine to gain mechanical work for power generation. Then, the steam is discharged into condenser to be cooled by the circulating water to become condensate, which is then sent to the steam sealing heater and the low pressure heater for preheating through condensation pump and is then sent to the deaerator. The main stream pipeline is equipped with a temperature reducer and a pressure reducer, which can be used to provide low pressure steam to other units without interruption.

The condensate is deoxidized in the deaerator and is then sent to the feed pump by low pressure water supply pipe. Then, the condensate is sent to the inlet header of coal economizer of waste heat boiler through high pressure water supply pipeline. Then, the condensate absorbs heat in the boiler and turns into superheated steam. Then, the steam reenters the turbine to gain mechanical work, which forms a work cycle.

The output voltage of the generator is 10.5 KV. According to the approval of the local power access system of the project, the transformer is promoted to the approved voltage and then transferred to the designated transformer station.

Gas and oil and electricity are generated from waste, air emissions are below government laid standards.

The pyrolytic oil and gas mixture (about 500˚C) from rotating bed will be continuously sprayed by 75˚C circulating pyrolytic water to 85˚C, and enter a wet de-dusting column where it will be sprayed by chilling circulation water pumped by a pump to remove the dust in pyrolytic gas. Finally, the mixture will enter two horizontal tube primary coolers operated in parallel (1W + 1S). The primary cooler will use the cooling water of two sections (32˚C circulating water and 16˚C cooling water) to cool pyrolytic gas to about 21-22˚C. The pyrolytic gas discharged at the lower part of primary cooler will enter two electric tar catchers operated simultaneously in parallel manner.

The high temperature pyrolytic oil and gas mixture will enter a separation unit where it will be continuously sprayed by 75˚C circulating pyrolytic water to 85˚C, and enter a wet dust-removing column where it will be sprayed by chilling circulation water to remove its dust, and then enter the horizontal pipe primary cooler. The primary cooler will use 32˚C circulating water and16˚C cooling water to cool the dust-removed pyrolytic gas to around 21-22˚C to further condensate its water, and the residual gas will enter electric tar catcher.

During the operation of electric tar catcher, a high voltage electric field is formed inside the catcher which causes the ionization of pyrolytic oil and gas that pass through the catcher. After charging, the pyrolytic oil particles will gather toward the precipitating electrode, and will be discharged through the bottom outlet. Following the removal of pyrolytic oil in the pyrolytic gas, the gas will be sent by Roots blower to dry DE Sox tower. The pyrolytic gas will enter the four-basket-type dry DE Sox tower installed with desulfurizer from the lower part of tower, and be discharged from the upper part of the tower so that the tower newly replaced with desulfurizer is still at the end to achieve best desulphurization effect.

The separated pyrolytic oil and circulating pyrolysis water will enter a mechanical oil-water separation tank. The light oil separated from the tank will flow into an intermediate tank, while the heavy oil at the bottom of separation tank will be pumped by a pump to the intermediate tank, finally, the pyrolytic oil in intermediate tank will be sent by a transfer pump to boiler.

It can consume any organic waste and convert into energy and removes risks associated with landfills. It can also consume all other wastes such as plastics, rubber, paper, agri waste products, bio medical, feedstock and numerous other waste which have calorific value. Glass and metal waste cannot be part of this process.

The pyrolysis process is a reaction process that breaks the chemical bond of organic polymer in feedstock in an anaerobic and high temperature atmosphere to release various volatile matters to produce carbide, retorting gas (H2, CH4, CO etc.) and coagulable liquid (tar, water, acid).

The core advantages of new MSW pyrolysis process independently developed by Shenwu Group include that the generation of dioxin and heavy-metal-bearing fly ash is eliminated at the source, and the emission index of other pollutants reaches the ultra-clean emission requirements of gas-fired boiler, therefore the cleanliness is very high. Furthermore, this process successfully achieves the large-scale, stable and continuous operation, and solves the world problem that MSW pyrolysis treatment technology cannot be performed in a large-scale and continuous industrial production manner. This process has also passed the scientific and technological achievement appraisal by MIIT, which is appraised as “An International leading process”.

The core equipment of the pyrolysis process is rotating bed. The circular chamber of rotating bed is divided into feeding zone, preheating zone, first reaction zone, second reaction zone, third reaction zone and discharging zone. The regenerative radiant tube is installed at both sides of furnace chamber of every reaction zone. The purified pyrolytic gas will be used to supply heat for the heating and pyrolysis of feedstock. The temperature of every reaction zone inside the furnace can be controlled by adjusting the gas and air supply amount of regenerative radiant tube to achieve optimal pyrolysis effect. The sorted and crushed MSW delivered from pretreatment shop will enter rotating bed, and rotate together with the hearth to pass through the above-mentioned zones in sequence. In this process, the MSW will undergo three stages, i.e. drying, volatile precipitation and polymer cracking. The pyrolysis flow can be described as “feeding – preheating – heating – oil and gas discharging – residual solid discharging”. By adjusting the rotation speed of hearth, the feedstock distributing thickness and heating time can be changed.

The main products of rotating bed include the oil and gas mixture and pyrolytic carbon, which are often called pyrolytic oil, pyrolytic water, pyrolytic gas and pyrolytic carbon. The pyrolytic oil, water and gas will enter the oil and gas separation unit in the form of mixed gas, while the pyrolytic carbon will be sent to boiler power generation unit.