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Issue 1/June 2017

Die casting machines create highly greasy and polluted smoke. Changchun has a median daytime temperature of -4.4 °C degrees during the winter period (October to the end of April). The desired inside temperature is with 17 °C degrees around room temperature. The manufacturing hall of the foundry has a total volume of 78,000 m3 and is equipped with 20 die casting machines in several sizes (from 640 tons up to 2500 tons machines). The management has now several air treatment options to purify the waste air of the die casting machines.

压铸机会产生高度油腻和严重污染的烟雾。长春冬天的白 天平均气温-4.4°C(10月至4月底)。内部所需温度为室温 17°C左右。铸造生产大厅的总体积为78000立方米,配备了 20台多种尺寸的压铸机(机器重量在640吨到2500吨之间)。 管理部门现在有几种净化压铸机废气的空气处理方法可选。

First method: Conventional exhaust air ventilation system A conventional exhaust ventilation system works in a very easy way: the waste air is led outside through complex exhaust ducts and chimneys at the roof of the building and fresh air from outdoors is led inside through the inlets. This method ensures clean air at the workplace but creates high follow-up costs. The main reason: allowing fumes to get dispersed in the hall first a nonessential increase of the exhaust air volume is created, which needs to be purified. And a high air volume always means high energy consumption. Practical examples show that generally the ambient air inside the hall has to be changed by a conventional ventilation system 10 to 12 times per hour by air from outdoors to keep it clean. In our example this means an air volume exchange of at least 781,200 m3 per hour, plus high pressure loss (generated by the exhaust air ducts) and high heating costs of the incoming air. This results in an annual operation cost of 19,056,770 CNY and carbon dioxide emissions of about 3,500 tons per year.

第一种方法:使用传统的排气通风系统 传统的排气通风系统的工作方式非常简单:该系统通过复杂 的排气管道和屋顶烟囱将废气排到室外,再通过进气管道 将新鲜空气从户外吸入室内。这种方法可以确保生产大厅 空气清洁,但会产生较高的后续成本。主要原因:让气体先在 大厅里扩散,增加了不必要且需要净化的废气量。且高风量 意味着较高的能量消耗。实例表明,通常情况下,传统的通 风系统每小时要更换10-12次大厅内的空气才能保持空气清 洁。在我们的示例中,这意味着每小时至少交换了781200立 方米空气,加上高压损失(排气管道中产生的)和进气加热 损耗。这造成了每年19056770元的运营成本和3500吨/年的 二氧化碳排放量。

In the recirculating air mode, the exhaust air is highly purified so that it can be fed back into the work area. Therewith, there is no heat loss during the cold winter months. Accordingly, the recirculating air mode contains the highest potential of energy savings.

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在空气再循环模式下,废 气被高度净化,可以重 新供应给工作区域。于 是,在寒冷的冬天没有热 量损失。因此,空气再循 环模式具备最高的节能 潜力。

Foundry Planet Magazine

Foundry-planet e-Magazine Diecasting-Dialogue ISSUE 1 | JUNE 2017  
Foundry-planet e-Magazine Diecasting-Dialogue ISSUE 1 | JUNE 2017