开心色99×xxxx-开心色99xxxx开心色-开心色xxxx-看草逼-日韩啪啪片-日韩日韩

INTRODUCTION簡介

The majority of powders that are used in the processing industries are combustible.  An explosion will occur if the concentration of the combustible dust that is suspended in air is sufficient for flame propagation when ignited by a sufficiently energetic ignition source.  It should be noted that as far as dust clouds are concerned, the terms “combustible”, “flammable”, and “explosible” all have the same meaning and could be used interchangeably.
大多數(shù)加工行業(yè)中的粉塵是“可燃的”。當懸浮在空氣中的可燃性粉塵達到支持火焰?zhèn)鞑サ臐舛葧r，同時點火源有足夠能量，爆炸就會發(fā)生。就粉塵云而言，術(shù)語“可燃”，“易燃”，和“易爆”都具有相同的含義，可以互換使用。

To eliminate/control dust cloud explosion hazards the following activities are required:為了消除/控制粉塵云爆炸危害，應(yīng)采取以下措施：
- Understanding of the explosion characteristics of the dust, 了解粉塵的爆炸特性，
- Identification of locations where combustible dust clouds are or could be present during normal and abnormal conditions, 
- 識別在正常和異常情況下，可燃性粉塵云存在或可能會存在的場所
- Identification of potential ignition sources that could be present under normal and abnormal conditions,
- 識別在正常和異常情況下，可能存在的點火源，
- Proper plant design to eliminate and/or control the occurrence of dust explosions and protect people and facilities.
- 正確的廠房設(shè)計以消除和/或控制粉塵爆炸的發(fā)生，保護人員和設(shè)備。
As is highlighted above, in order to assess the risk of a dust explosion in a facility and to select the most appropriate basis of safety, explosion characteristics of the dust(s) that are being handled / processed in the facility should be determined.  The explosion characteristics of dusts normally fall within two groups, “l(fā)ikelihood of an explosion (Ignition Sensitivity)” and “consequences of an explosion (Explosion Severity)”.  These two groups of tests are discussed below:
如上文所強調(diào)的，為了評價粉塵在設(shè)施中爆炸的風(fēng)險及選擇適當?shù)陌踩疽螅瑧?yīng)先確定設(shè)施中需處理/處置的粉塵的爆炸特性。粉塵的爆炸特性通常分為兩類，“爆炸的可能性（點火感度）”和“爆炸的后果（爆炸烈度）”。關(guān)于這兩類特性的測試在下文中討論：

Laboratory Tests to Determine the “Likelihood of an Explosion (Ignition Sensitivity)”
實驗室測試確定“爆炸的可能性（點火感度）”

Explosion Classification (Screening) Test爆炸分類（篩選）測試
The Explosion Classification test determines whether a dust cloud will explode when exposed to an ignition source.  The test results in a material being classified as either combustible or non-combustible.爆炸分類測試用來確定粉塵云暴露在點火源環(huán)境下發(fā)生爆炸的可能性。測試結(jié)果將可以區(qū)分材料的可燃或不可燃。

Minimum Explosible Concentration (ASTM E151)最小爆炸濃度（ASTM E151）
The Minimum Explosible Concentration (MEC) test determines the lowest concentration of dust cloud in air that can give rise to flame propagation upon ignition.  This test answers the question “how easily can an explosible dust cloud be formed?”
最小爆炸濃度（MEC）測試確定的粉塵云在空氣中產(chǎn)生火焰?zhèn)鞑ニ璧淖钚舛取＿@個測試可以回答“為何這么容易形成爆炸性粉塵云？”

Minimum Ignition Temperature (ASTM E-2021)最小點火溫度（ASTN E-2021）
The Minimum Ignition Temperature (MIT) test determines the lowest temperature capable of igniting a dust dispersed in the form of a cloud.  The MIT is an important factor in evaluating the ignition sensitivity of dusts to such ignition sources as heated environments, hot surfaces, and friction sparks.
最小點火溫度（MIT）測試確定能點燃擴散的粉塵云所需的最低溫度。MIT是一個評價粉塵對加熱的環(huán)境，高溫?zé)岜砻婕澳Σ粱鸹ǖ赛c火源點火感度的重要參數(shù)。

Minimum Ignition Energy (ASTM E2019) 最小點火能量(ASTM E 2019)
The Minimum Ignition Energy (MIE) test determines the lowest electrostatic spark energy that is capable of igniting a dust cloud at its optimum concentration for ignition.  The test is used primarily to assess the susceptibility of dust clouds to ignition by static sparks.
最小點火能量（MIE）測試確定點燃粉塵云最佳濃度時所需的最小靜電火花能量。本試驗主要用于評估粉塵云被靜電火花點燃的感度。

Electrostatic Volume Resistivity (ASTM D257)靜電體電阻率(ASTM D257)
Volume Resistivity classifies powders as low, moderately, or highly insulating.  Insulating powders have a propensity to retain static charge and can produce hazardous electrostatic discharges when exposed to grounded facilities, equipment, or personnel.按體積電阻率將粉末分為低，中等或高絕緣。絕緣粉末具有攜帶靜電電荷的特質(zhì)并能在接觸到的設(shè)施，設(shè)備，人員時產(chǎn)生危害性靜電釋放。

Electrostatic Chargeability (General Accordance with ASTM D257)靜電負荷(與ASTM D257總體一致)
Electrostatic Chargeability is a measure of the propensity of powder particles to become charged when flowing through conveyances or when handled in containers.  The test provides data that can be used to develop appropriate materials handling guidelines from an electrostatic hazards point of view.
靜電負荷是粉塵粒子在傳輸過程中流動或用容器進行處理時釋放靜電的能力。該實驗用來提供物質(zhì)的相應(yīng)數(shù)據(jù)，從而從控制靜電危害的角度制定處理此類物質(zhì)的方針。

Limiting Oxidant Concentration極限氧濃度
The Limiting Oxidant Concentration (LOC) test determines the minimum concentration of oxygen (displaced by an inert gas such as nitrogen) capable of supporting combustion.  An atmosphere having an oxygen concentration below the LOC is not capable of supporting combustion and thus cannot support a dust explosion.  極限氧濃度（LOC）測試確定能夠支持燃燒的最小氧濃度（實驗中通過惰性氣體進行置換，例如氮氣）。低于LOC的大氣環(huán)境無法燃燒，因此也不能產(chǎn)生粉塵爆炸。