摘要:
Disclosed is a method for warming an after-treatment system in which a burner 14 is arranged upstream of a particulate filter 12 (exhaust purifying member) incorporated in an exhaust pipe 11 and the particulate filter 12 is adapted to be heated by combustion with the burner 14. On condition that an ambient temperature surrounding the burner 14 is below a predetermined temperature, the energization is conducted to an electromagnetic valve-type injector 15 serving for fuel spray of the burner 14 with the fuel supply being stopped. The energization brings about Joule heat generated in an electromagnetic coil inside the injector 15 to make the warming.
摘要:
A fuel spray nozzle 16 has a cylindrical spray block 18 with an inner air passage 17 for flow of nebulizing air 4′ and a fuel injection valve 20 for injection of fuel intermediately of the inner air passage 17 in the spray block 18 at a flow rate adjusted by duty control. The nebulizing air is introduced into the spray block 18 through a base end of the block at a flow velocity of 9 m/s or more and blown out of an injection port 21 at a tip end of the block.
摘要:
Injection nozzle 7 and electrode rods 8 and 9 (ignitor) are surrounded by double-cylinder flame stabilizer 10. Toroidal blocking plate 13 closes between inner and outer cylinders 11 and 12 of the stabilizer at its distal end whose proximal end is connected with line 15 for introducing combustion air 14 to between the cylinders. Inflow holes 16 are formed throughout the inner cylinder at its proximal end. Peripheral fins 17 are formed peripherally on the inner cylinder radially inwardly through cutting and bending-up at positions shifted from the inflow holes toward the distal end of the inner cylinder such that combustion air is introduced from circumferentially to form swirling flow inside the inner cylinder. End fins 18 are formed on the blocking plate in fuel injection direction through cutting and bending-up such that combustion air is discharged circumferentially to form swirling flow around flame 21.
摘要:
Enabled is reliable detection of abnormality in a NOx emission control system. Disclosed is a method for detecting abnormality in an exhaust emission control device with a reducing agent (urea water 17) being added to selective reduction catalyst 10 incorporated in an exhaust pipe 9 so as to reduce and purify NOx. Temperature of the catalyst during an operation period is monitored to record a cumulative time for each of temperature zones. On the basis of the recorded cumulative time for each of the temperature zones, a deterioration coefficient of NOx reduction performance is determined for each of the temperature zones. A standard NOx reduction ratio predetermined for each of the temperature zones is multiplied by the determined deterioration coefficient for each of the temperature zones to update the standard NOx reduction ratio. The updated standard NOx reduction ratio is used in a next operation to compare an actually measured NOx reduction ratio with the standard NOx reduction ratio on the measured temperature zone. It is determined that there is abnormality when deviation of the actually measured NOx reduction ratio from the standard NOx reduction ratio does not fall within a required range.
摘要翻译:启用是在NO x发射控制系统中的异常的可靠检测。 本发明公开了一种利用还原剂(尿素水17)在废气排放控制装置中检测异常的方法,所述还原剂(尿素水17)被加入到排气管9中的选择还原催化剂10上,以便减少和净化NO x 。 监测操作期间催化剂的温度以记录每个温度区的累积时间。 基于每个温度区域的记录的累积时间,确定每个温度区域的NO x降低性能的劣化系数。 将每个温度区域预先确定的标准NO x x减少率乘以每个温度区域的确定的劣化系数,以更新标准的NO x减少率。 在下一个操作中使用更新的标准NO x x减少比来将实际测量的NO x x减少比与标准NO x x减少比进行比较 在测量的温度区。 确定实际测量的NO x x减少比率与标准NO x减少比的偏差不在所需范围内时存在异常。
摘要:
Excessive generation NO2 by oxidation catalyst arrangement upstream of a selective reduction catalyst is suppressed to prevent falling of NOx reduction rate. A selective reduction catalyst 4 capable of selectively reacting NOx with ammonia even in the presence of oxygen is incorporated in an exhaust pipe 3 from an engine 1. A pair of oxidation catalysts 5A and 5B are arranged in parallel with each other and upstream of the selective reduction catalyst. In an operation condition with low exhaust temperature, amounts of the exhaust gas 2 distributed to the oxidation catalysts 5A and 5B are adjusted so as to make NO/NO2 ratio in the exhaust gas 2 to about 1-1.5. In an operation condition with higher exhaust temperature where the NOx reduction rate is less affected by the NO/NO2 ratio, as a countermeasure against increasing, leaking ammonia, passage changeover is conducted to pass the exhaust gas 2 in backflow through the selective reduction catalyst 4 and the oxidation catalysts 5A and 5B, so that ammonia passing through the selective reduction catalyst 4 without reacted is oxidized in the oxidation catalysts 5A and 5B.
摘要翻译:通过选择性还原催化剂上游的氧化催化剂配置过量产生NO 2 2被抑制,以防止NO x降低率下降。 即使在有氧的情况下也能够使NO x选择性地与氨反应的选择还原催化剂4从发动机1中引入排气管3中。 一对氧化催化剂5A和5B在选择还原催化剂的彼此并排并排配置。 在排气温度低的运转条件下,分配到氧化催化剂5A和5B的废气2的量被调整为使废气2中的NO / NO 2比率达到约 1-1.5。 在NO x NO 2比率较小的NO x NO 2还原率较小的排气温度较高的运行条件下,作为增加氨泄漏的对策,通过转换 通过选择还原催化剂4和氧化催化剂5A和BB使废气2回流通过,使得在氧化催化剂5A和5B中氧气通过选择还原催化剂4而没有反应的氨被氧化。
摘要:
An exhaust emission control device with a plasma generator received in a filter casing incorporated in an exhaust pipe for capturing particulates and capable of conducting electric discharge so as to generate plasma in the exhaust gas at a capturing place and with a power supply for impressing voltage on the plasma generator. The plasma generator is unitized and arranged in plurality. A control switch is provided for sequential changeover of the connection of the power supply to the plural units of the plasma generator. A processing capability comparable to a single, large-sized plasma generator is obtained while increase in size of the power supply is prevented.
摘要:
An injection amount of a reducing agent such as urea water is properly and adequately controlled to keep a NOx reduction ratio as high as possible. Disclosed is a method for controlling an exhaust emission control device wherein urea water 17 (reducing agent) is added to selective reduction catalyst 10 incorporated in an exhaust pipe 9 so as to reduce and purify NOx. A first-order lag response model corresponding to the exhaust temperature upstream of the catalyst 10 is used to estimate catalyst temperature for each of cells into which the catalyst is minutely divided. Cell volumes for each of temperature zones are summed up on the basis of the estimated temperatures for the cells. The cell volume summation for each of the temperature zones is divided by the whole volume of the catalyst to determine temperature distribution volume ratio. The temperature distribution volume ratio for each of the temperature zones is multiplied by a reference injection amount of the urea water 17 which is determined in consideration to an operation status of a current engine 1 on the assumption that the catalyst temperatures are all within the temperature zone. The calculated values for the respective temperature zones are summed up into a directive injection amount of the urea water 17.
摘要:
When urea water U is injected by an addition nozzle 7 upstream of NOx reduction catalyst 6 incorporated in an exhaust passage 5 of a diesel engine 1 so as to reduce and purify NOx in exhaust G, both a value measured by a NOx concentration sensor 9 upstream of the nozzle 7 and a value measured by a NOx concentration sensor 12 downstream of the catalyst 6 are corrected by using a primary response model depending upon a flow rate and a temperature of exhaust G. The NOx reduction ratio is obtained on the basis of these corrected NOx concentration values. Rectified are time lag of measuring of a value by the downstream NOx concentration sensor 12 from measuring of a value by the upstream NOx concentration sensor 9 in a case of the exhaust G having a lower flow rate, and error due to lowering of NOx reduction processing speed in a case of the exhaust having a lower temperature.
摘要翻译:当尿素水U通过并入在柴油发动机1的排气通道5中的NO x x还原催化剂6上游的加料喷嘴7喷射以减少和净化NO x x 在排气G中,由喷嘴7上游的NO x 2 x浓度传感器9测量的值和由催化剂下游的NO x x浓度传感器12测量的值 6通过使用根据流量和排气G的温度的主要响应模型来校正。减压比是基于这些校正的NO < 浓度值。 在排气的情况下,通过上游侧NO x 2浓度传感器9的值的测量,整流是由下游的NO x x浓度传感器12测量值的时间滞后 G具有较低的流速,并且在排气温度较低的情况下由于降低NO X 2还原处理速度而导致的误差。
摘要:
When urea water U is injected by an addition nozzle 7 upstream of a NOx reduction catalyst 6 incorporated in the passage 5 so as to reduce and purify NOx in exhaust gas G, a target adsorption amount curve is set by shifting to lower temperature side a saturated adsorption amount curve of ammonia to the catalyst. A target adsorption amount of the reducing agent corresponding to the catalyst temperature is calculated and an actual adsorption amount of the reducing agent to the catalyst is determined. The amount of the urea water U to be added upstream of the catalyst is reduced when the actual adsorption amount reaches the target adsorption amount, and is increased when the actual adsorption amount is lower than the target adsorption amount. Thus, the adsorption amount of ammonia is secured while preventing ammonia from adsorbing so as to save the urea water U.
摘要翻译:当尿素水U通过加入喷嘴7注入到并入通道5中的NO x x还原催化剂6的上游,从而减少和净化废气G中的NO x 通过将氨的饱和吸附量曲线向催化剂转移到较低温度侧来设定目标吸附量曲线。 计算与催化剂温度对应的还原剂的目标吸附量,并确定还原剂对催化剂的实际吸附量。 当实际吸附量达到目标吸附量时,加入催化剂上游的尿素水U的量减少,并且当实际吸附量低于目标吸附量时增加。 因此,确保氨的吸附量,同时防止氨吸附以节省尿素水U.
摘要:
Excessive generation NO2 by oxidation catalyst arrangement upstream of a selective reduction catalyst is suppressed to prevent falling of NOx reduction rate.A selective reduction catalyst 4 capable of selectively reacting NOx with ammonia even in the presence of oxygen is incorporated in an exhaust pipe 3 from an engine 1. A pair of oxidation catalysts 5A and 5B are arranged in parallel with each other and upstream of the selective reduction catalyst. In an operation condition with low exhaust temperature, amounts of the exhaust gas 2 distributed to the oxidation catalysts 5A and 5B are adjusted so as to make NO/NO2 ratio in the exhaust gas 2 to about 1-1.5. In an operation condition with higher exhaust temperature where the NOx reduction rate is less affected by the NO/NO2 ratio, as a countermeasure against increasing, leaking ammonia, passage changeover is conducted to pass the exhaust gas 2 in backflow through the selective reduction catalyst 4 and the oxidation catalysts 5A and 5B, so that ammonia passing through the selective reduction catalyst 4 without reacted is oxidized in the oxidation catalysts 5A and 5B.
摘要翻译:通过选择还原型催化剂上游的氧化催化剂配置产生的过量的NO 2被抑制,以防止NO x还原率下降。 即使在有氧的情况下也能够选择性地使NOx与氨反应的选择还原催化剂4从发动机1引入到排气管3中。一对氧化催化剂5A和5B彼此平行配置,并且在选择性 还原催化剂。 在排气温度低的运转条件下,分配到氧化催化剂5A,5B的废气2的量被调整为使废气2中的NO / NO2比例为约1-1.5。 在NO x NO 2比率较小的NOx还原率较高的排气温度的作业条件下,作为增加氨泄漏的对策,进行通过转换使废气2回流通过选择还原催化剂4 和氧化催化剂5A和5B,使得通过选择还原催化剂4而没有反应的氨在氧化催化剂5A和5B中被氧化。