Chapter 341 - Acids and Bases (IV)
"Not exactly," Xu Yingjie replied. "We call it electrolyte. The caustic soda content is less than ten percent, and it contains substantial impurities. Further separation treatment is required."
"Careful—chlorine gas!" Ji Situi clapped Xu Yingjie's shoulder.
"What? What is it?" Bai Yu started to lean forward.
"Don't move!" Xu Yingjie's voice carried a note of excitement. His mind wasn't on chlorine's uses for disinfection, environmental purification, or hydrochloric acid production. He was thinking: Poison gas.
Chlorine was common enough, but it had been the first poison gas deployed in modern warfare. During the Great War, its battlefield results had been devastating—countless souls lost to its yellow-green embrace. Better still, chlorine was easy to produce. It could serve as a superweapon in this timeline. Whether Manchu White Banner cavalry, Guanning Iron Horse, Japanese Gokenin, or Cromwell's Ironsides—none of them could withstand it. Encountering chlorine meant only one thing: death.
Currently, the transmigrators' industry couldn't manufacture pressurized vessels, so chlorine storage remained impossible. But Xu Yingjie knew the Weapon Research Group harbored its share of creative minds. Perhaps they could devise something suitably wicked.
The yellow-green gas rose through the glass tube, and every transmigrator present held their breath. Meanwhile, a small fan blade in another glass tube began to spin—indicating that a second, colorless electrolysis product was also emerging. Hydrogen.
"Everyone listen carefully." Ji Situi began safety instruction for the workers. "This yellow gas is chlorine. It's poisonous..."
Watching Ji Situi explain chlorine, hydrogen, poisoning prevention, and explosion risks to a cluster of only-partially-comprehending indigenous workers, Bai Yu silently vowed never to set foot in this chemical plant again. Too dangerous.
The produced hydrogen was routed to the only modern device in the entire system: the Hydrochloric Acid Reactor. Hydrogen was fed into the reactor and ignited, then chlorine was introduced. The reaction generated hydrogen chloride gas, which was cooled, absorbed in water, and collected as hydrochloric acid.
The reaction was extraordinarily dangerous. If the chlorine content in the hydrogen grew too high, the mixture would explode. The solution lay in rigorous control of chlorine intake during the reaction—surrounding the toxic chlorine with excess hydrogen, ensuring complete chlorine reaction while preventing both air contamination and explosive mixtures.
Given the extreme hazard, Ji Situi had never considered indigenous equipment for this step. The reactor was purchased directly from the modern timeline.
Hydrochloric acid production consumed only a portion of the chlorine. The remainder was piped to a small reaction tower nearby. Layered with dried slaked lime, the tower absorbed chlorine to produce calcium hypochlorite—more commonly known as bleaching powder.
As the most widely available effective disinfectant, mass production of bleaching powder marked a new peak in the Transmigration Group's epidemic prevention capabilities. For the densely populated settlements along both banks of the Wenlan River, this was transformative. And when the army launched expeditions, commanders would no longer need to worry about water sanitation along the march route.
Complete absorption of chlorine by slaked lime was difficult to achieve; waste gas inevitably carried some chlorine away. To maximize chlorine utilization and improve air quality, a final waste gas absorption process was implemented.
Waste gas from the absorption tower was piped to an absorption vat containing milk of lime prepared from slaked lime. The chlorine in this waste gas reacted with the milk of lime to produce calcium chlorate and calcium chloride.
Once the milk of lime was saturated with chlorine, it was pumped into a concentration pot, heated, and then cooled to crystallize out calcium chlorate—useful as a herbicide. The remaining liquid was heated and concentrated to yield calcium chloride. This approach achieved essentially zero chlorine emissions.
As for the electrolyte continuously flowing from the electrolytic cells, it now contained approximately ten percent caustic soda. However, sodium chloride content remained higher still; such dilute caustic soda liquid was unusable and required concentration.
The equipment Ji Situi employed for concentration was brutally simple: a large iron pot, heated directly over a coal fire ignited with kindling. The fumes were so powerful that anyone not wearing safety goggles fled the building.
"Isn't this level of pollution excessive?" Bai Yu called from outside.
"It is—but we don't have evaporation pans! And it wastes coal!" Ji Situi's voice was muffled by his chemical mask. "We'll upgrade when the machinery factory can provide proper equipment."
After prolonged boiling, crystals began precipitating at the bottom of the pot beneath the alkali liquid, accumulating steadily.
"Bai Yu! Scoop it out with the ladle! Be careful not to bring up the alkali liquid with it."
Bai Yu hurriedly took the specially-made wooden ladle and positioned himself by the pot, scraping crystals from the bottom.
"Mind your safety." Ji Situi watched anxiously. This pot—originally from Gou Village, once used to cook pig swill—had an enormous diameter. One misstep meant falling in, and that would be the end.
Bai Yu carefully extracted the crystals. Even through his protective mask, the steam rising from the pot stung his nose.
"This is salt, isn't it?"
"Correct—genuine refined salt."
The extracted salt was transferred to drying boards, washed several times with dilute alkali liquid, then rinsed with saturated refined brine. What remained were snow-white crystals with sodium chloride purity exceeding ninety-five percent—pure enough for preparing medical-grade physiological saline.
The electrolyte from which salt had precipitated was returned to the pot and heated further until the alkali concentration reached approximately thirty percent, rendering it suitable for chemical applications. Additional concentration and drying could produce solid caustic soda, but coal consumption made this economically unfeasible for now.
The successful manufacture of sulfuric acid, hydrochloric acid, and caustic soda electrified the Industrial and Energy Committee. Wang Luobin, Zhan Wuya, and others made regular pilgrimages to these crude workshops, studying the improvised equipment.
Though primitive in appearance, the benefits these facilities delivered were immeasurable. According to Ji Situi's calculations, given adequate raw materials and energy, the Contact Process Sulfuric Acid Workshop—operating with fifteen workers in three shifts, 345 days per year—could produce one ton of 98% concentrated sulfuric acid daily, scaling to 1.2 tons when necessary. The Salt Electrolysis Workshop—operating with twenty-four workers in three shifts, 345 days per year—could produce 47.5 tons of caustic soda, 87 tons of bleaching powder, 2 tons of calcium chlorate, and 6 tons of calcium chloride annually, plus 47.5 tons of refined salt (95% purity) and 30 tons of hydrochloric acid.
By modern standards, these figures were negligible. But for the Planning Committee—where, not long ago, chemical allocations had been measured in milliliters and grams—the output of these two workshops represented an extraordinary windfall.
Even Shi Niaoren made the journey. Seeing the 95% high-purity sodium chloride Ji Situi had prepared for him, his face split into a grin he couldn't suppress. This solved an enormous problem: infusion-grade physiological saline was now feasible. Bleaching powder was an obvious boon for the Ministry of Health. And the crude calcium chloride, once refined by the pharmaceutical factory into calcium chloride injection solution, could treat tetany caused by hypocalcemia, intestinal and ureteral colic, urticaria, exudative edema, and pruritic skin diseases. It would also address Vitamin D deficiency rickets, osteomalacia, and calcium supplementation needs for pregnant and lactating women. The physical health of the local population stood to improve dramatically.
With adequate hydrochloric acid, the pharmaceutical factory's planned glucose production could proceed as well. Shi Niaoren immediately contacted Wu Nanhai, requesting starch raw materials so they could begin planning a glucose workshop.
Wu Nanhai, for his part, was overjoyed by the unanticipated arrival of herbicide—the calcium chlorate he hadn't even dared request. He immediately demanded full allocation of all relevant output. He also inquired eagerly about ammonium sulfate production timelines, hoping to achieve record-breaking hybrid rice yields.
Representatives from the Ministry of Light Industry arrived to ask about caustic soda and sulfuric acid quotas. With these chemicals, they could produce pristine white paper; soap production was never in doubt. However, soap manufacturing required coordination between the Chemical Department and Light Industry, since the Chemical Department needed to recover glycerol as a byproduct of the soap-making process.
It was like a snowball effect. Once technical bottlenecks were broken, production lines that had been stalled suddenly began moving. Product variety expanded instantly; productive capacity surged.
The military department responded swiftly as well. That same day, Xi Yazhou called to request that the Chemical Department seriously consider chlorine's military value and potential deployment as a weapon.
Direct chlorine release remained impractical. Xu Yingjie and the weapon research group studied the problem and developed a chlorine landmine: a jar of hydrochloric acid positioned above a packet of calcium hypochlorite powder—bleaching powder—strapped to a thirty-gram guncotton charge. The explosion would atomize both substances into a reactive mist. The consensus was that, if deployed, multiple mines should be detonated simultaneously for effect.
Some suggested developing poison gas artillery shells on the same principle—simply adapting the structure to withstand howitzer firing.
"Not recommended." Xu Yingjie couldn't envision anyone scrambling across a battlefield while lugging jars of hydrochloric acid.
"In my opinion," Lin Shenhe from the Artillery R&D Group offered a concluding remark, "rather than poison gas shells or mines, we'd be better off filling glass bottles with hydrochloric acid and throwing them like grenades."
The response from across the organization was overwhelmingly positive; praise poured in from every department. But as head of the chemical department, Ji Situi took little pleasure in it. Behind the impressive catalog of products and production figures lay high energy consumption and an extremely unstable production state.
The salt electrolysis workshop alone consumed 160 tons of salt, 60 tons of quicklime, 0.5 tons of hydrochloric acid, 35 tons of coal, 140,000 kilowatt-hours of DC electricity, and 1,500 tons of water annually. This represented considerable material and energy demand—especially for electricity and industrial water. Bopu Power Station's installed capacity was only 213 kilowatts; a single electrolysis workshop would consume nearly one-tenth of the station's annual output. Power shortage had become the primary obstacle to the workshop's operation. Originally scheduled to launch the previous year, the project had been postponed repeatedly. Only after the second-phase expansion of Bairen Tan Hydropower Station succeeded—and a locomobile from there was transferred to Bopu, doubling installed capacity—could production finally begin.
Ji Situi planned to gradually replace the current crude equipment once the machinery department's manufacturing capabilities improved. This high-consumption, high-pollution production model was not sustainable.
Another drawback of the "indigenous launch" approach was that things "looked very beautiful" on paper—but actual operation exposed problem after problem that the construction pamphlets never mentioned.
The Contact Sulfuric Acid Workshop was the worst offender. Since startup, it had suffered numerous faults, major and minor. Most serious was the low conversion rate—below seventy percent—which caused some sulfuric acid batches to emerge at only eighty percent concentration, requiring re-blending to meet standards. The blower outlet sprayed acid mist everywhere, corroding the floors. Chimney exhaust carried substantial acid, which condensed into acid rain on contact with moist air, eroding and destroying every temporary structure near the stack. Several workers sustained mild acid burns and were sent to the hospital.
Ji Situi, Xu Yingjie, and technicians from the machinery and construction departments made six consecutive modifications to the entire system. The absorption tower was dismantled and refilled multiple times. A pebble dust collector was added to the converter; coke absorbent was installed at the air outlet; acid-mist-removing tile fragments and coke were added atop the absorption tower... Problems were identified, meetings held, reference books consulted—fortunately, the Grand Library held extensive materials—and solutions found one by one. It took a full month of trial and error before production stabilized.
Just as the sulfuric acid workshop steadied, the electrolysis workshop suffered several small-scale accidents. The most outrageous involved someone who had taken an interest in the hydrogen—identifying it as potential material for a future balloon observation corps—and insisted on filling balloons with hydrogen inside the workshop. This individual was wearing synthetic fiber clothing. Upon contact with the equipment...
One percent of his body surface suffered second-degree burns. He was rushed to the hospital. The entire electrolysis workshop was paralyzed for ten hours. Furious, Ji Situi had the workshop fenced off with bamboo barriers and a skull-and-crossbones sign posted prominently outside. No unauthorized entry or exit.
Shi Niaoren returned from his visit to the Bopu Chemical Plant, having secured supply agreements for several urgently needed materials from both the Planning Committee and Chemical Department. He stopped by the Bairen City dormitory area to collect a sample before heading back to the General Hospital.
"Touch here, touch again..."
Humming Eighteen Touches under his breath, Shi Niaoren strolled into Bairen General Hospital carrying several bags of stool samples. Ye Yuming passed by and muttered in bewilderment, "Has this fellow gone mad from smelling excrement all day?"
The real reason was nothing of the sort. Shi Niaoren settled into his "First Medical Examination Center in This Timeline," crossed his legs, stacked his specimen jars, and smiled with renewed purpose. The Chemical Department's successful launch had rekindled his enthusiasm for the pharmaceutical factory—enthusiasm that had been cooling. His drive surged. What other medicines might now be within reach? This news was worth ten years of effort. There truly were capable people in the Transmigration Group.