China Aluminum Company Qinghai Branch is one and only specialization electrolyte factory, and it’s one of the large production and output electrolyte factory.
The aspect of environment protection, they completely administer “ Three At The Same Time”, obey to the environment protection law, build a perfect and completely environment protection manage system, take up with the “Three Depose”. Especially recent years, the company increase technology alteration, the contamination is let in normative way.
First, conquer the limitation of techniques
In the branch there are 6 coal boilers, the smoke contain too much dust because of the design problem. The smoke of coal boilers is still over proof through the two grade clean. By the year of 2005, the company invest 20.68 million Yuan to alteration the coal boiler into gas boiler, solve the exhaust gas of coal boiler. Realize the proof of CO2 put down 80%, sulfur dioxide put down 99%, the dust put down 90%, become into a good environment and economy benefit.
The 4 sets gas clean system is already run over 10 years, former system is lack of wind power, the designation of single trough is 6000m3/h, nor consider the air pressure factor, make the ability of transaction lower, it can’t fill the requirement of collect gas efficiency 98%. To reform more environment of workshop, promote cleanse efficiency and collect gas efficiency, by the year of 2004, the company invest 110 million Yuan to the space of No 4 and No 5 passage in electrolyte workshop, to build a new set of electrolyte gas cleanse system, they share in 100 electrolyte trough; the rest 160 electrolyte trough is shared by the former cleanse system. To keep the hop-pocket clean and reduce maintenance, the hop-pocket dust catcher adopt low pressure impulse dust catcher.
Second, invest to make sure that it can meet the standard.
With the production scale enlarged, the waste water are more and more. With the strict standard to the omit index, in 2003-2004 company invest 5.2million to purify the industrious waste water in the technology of “ impulsive congel – floating- filter with charcoal”. With this way, the floating is less than 20mg/l in the water, density of CODcr is less than 30mg/l, oil less than 2mg/l, which is far better than the <dirty water standard omit>. At the same time, we required to recycled the processed water back to the company. After using this, the recycled water are 1.53 million, with the 370 ton floater, 316ton CODcr and 44.2 ton oil.
In 2002-2004, the company has invest 5.8 million to realize the melt steps to reform the cave smoke by the enlarging the room, improve the wind for fuel, reforming the smoke reflecting wall and the inner formation, in this way, we solve the problem of smoke over the standard issue, and eliminate the black dragon above the company. Through the reformation to the smoke pot to the steamed, the branch smoke omitting lower from 547.56 ton to 20 per year, SO2 from 276.57 ton to 70 ton, receiving the outstanding environmental and economic effect.
Owing to the shabby appliance for the dust, the low effect and over the standard. For this, in 2003, the company invest 1.7 million to implement the reformation to the workshop. In 2004, we invested .67 million to carry out the charcoal mould crash the part. By improving the environment, we lower the cost to the material.
3 submit the inspection to the clear
in 2005, the company become the test clear unit for Chinese aluminimun company, the first one submitting the clear standard enterprise. Implementing the clear, the company has to ask for advise the technicians from material, artwork, management and skill to work out several candidates. And we will analysis the steps, while organizing the the high cost from tech and environment. At the final confirmation, we chose the medium and high cost to reform the steamed pot, charcoal stove to adjust the energy formation, using the clear natural gas to save the investment and regulation of energy. To the industrial waste water reformed comprehensively back to the production system and enhancing the branch company industrial water recycled using to save the water resource. After the reformation to the first and second stage purifying the smoke system, we can enhance the effectiveness and recycle more salt and aluminimum to decrease the waste of the energy. The company also hold the class of clean to raise up the sense of the staff. It has been passed clear inspection in 2006-8-8.